EPA-R2-73-23Z
MAY 1973 Environmental Protection Technology Series
Methods for
Pulp and Paper Mill Sludge
Utilization and Disposal
\**+J
Office of Research and Monitoring
U.S. Environmental Protection Agency
Washington, DC. 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were established to facilitate further
development and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards.
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EPA-R2-73-232
May 1973
METHODS FOR PULP AND PAPER MILL
SLUDGE UTILIZATION AND DISPOSAL
By
Dr. Thomas R. Aspitarte
Mr. Alan S. Rosenfield
Dr. Bernard C. Smale
Dr. Herman R. Amberg
Project 12040 ESV
Program Element 1B2037
Project Officer
Mr. Ralph.H. Scott
Pacific Northwest Environmental Research Laboratory
National Environmental Research Center
Corvallis, Oregon 97330
Prepared for
OFFICE OF RESEARCH AND MONITORING
U. S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D. C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402
Price $2,10 domestic postpaid or $1.79 QPO Bookstore
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EPA Review Notice
This report has been reviewed by the
Environmental Protection Agency _, and
approved for publication. Approval does
not signify that the contents necessarily
reflect the views and policies of the
Environmental Protection Agency, nor does
mention of trade names or commercial
products constitute endorsement or recom-
mendation for use.
ii
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ABSTRACT
Many pulp and paper mills are now faced with a serious
problem in disposal of primary treatment plant sludge.
The system selected by mills for sludge disposal or
utilization must be one that has a minimal overall impact
upon the environment.
The original project was designed to evaluate four methods
by which such fibrous sludge may be utilized. These
methods of sludge disposal were: (1) incineration in an
air entrained dryer-incinerator, (2) burning in hog fuel
boilers, (3) incorporation into soil as an amendment, and
(4) hydromulching for soil stabilization.
During the course of this study, other possible uses for
sludge were suggested and investigated. This report
therefore includes data from such experimental observations,
Disposal of sludge in incinerators or hog fuel boilers
will cost between $11 and $13/dry ton. At the mill site
sludge could be made available for other means of disposal
at costs between $7 and $20/dry ton, depending on the
degree of dewatering and form in which it would be handled.
Incorporation of sludge in farm soil was found to be. an
excellent method for disposal of large quantities of sludge,
In combination with crop production, however, certain
problems could arise. At high levels, such as 600 tons
per acre, a year fallow appears necessary in order to
obtain significant increases in crop yield. Crop yields
in fresh mixtures of low sludge levels and soil were
satisfactory provided adequate nitrogen was added.
Sludge alone or in combination with bark was competitive
as a hydromulch material in establishing grass stands on
steep embankments.
This report was submitted in fulfillment of Project 12040
ESV under the partial sponsorship of the Environmental
Protection Agency, in cooperation with Crown Zellerbach
Corporation, Camas, Washington.
iii
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CONTENTS
Section
I Conclusions
II Recommendations
III Introduction
IV Sludge Characteristics
V Incineration--Air Entrainment
VI Incineration--Hog Fuel Boilers
VII Sludge Processing and Costs
VIII Laboratory Studies
IX Greenhouse Studies
X Field Plot Studies
XI Mulching
XII Miscellaneous Uses
XIII Acknowledgments
XIV References
XV Appendices
Page
1
5
7
9
15
33
47
57
61
89
103
117
119
121
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FIGURES
PAGE
1 PRIMARY TREATMENT PLANT SHOWING SLUDGE
DISPOSAL AREA 16
2 AIR ENTRAINED INCINERATOR—SIDE VIEW 17
3 AIR ENTRAINED INCINERATOR 18
4 PRESSED SLUDGE—BURN WITH HOG FUEL 20
5 DRY SLUDGE—BURN WITH HOG FUEL 21
6 CARBON DIOXIDE RESPIROMETERS FOR DETERMINING
SLUDGE DECOMPOSITION RATE 48
7 TONS SLUDGE UTILIZED AT VARIOUS LOADINGS AT
DIFFERENT C:N RATIOS 50
8 TONS SLUDGE UTILIZED AT VARIOUS LOADINGS AT
DIFFERENT C:N RATIOS 51
9 SLUDGE DECOMPOSITION—NO NITROGEN ADDED 52
10 SLUDGE DECOMPOSITION—OPTIMUM NITROGEN ADDED 53
11 SLUDGE DECOMPOSITION IN 120 DAYS FOR SANDY AND
CLAY SOIL 54
12 EFFECT OF NITROGEN ADDITION AND SLUDGE ON
SUNFLOWER YIELD 60
13 EXPERIMENTAL PLOT LAYOUT FOR SLUDGE UTILI-
ZATION PROJECT 62
14 AERIAL PHOTOGRAPH OF SLUDGE AMENDED PLOTS 63
15 COMPARISON OF TWO PLOTS RECEIVING TOTAL OF
600 T/A SLUDGE 87
16 EFFECT OF SLUDGE ADDITION ON WILTING OF CORN 88
17 HYDROMULCH APPLICATION ON SIMULATED HIGHWAY
ROAD CUT 90
18 GRASS GROWTH—HYDROMULCH PLOTS, 4/13/71 93
vi
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PAGE
19 DESIGN SHOWING HYDROMULCH PLOTS 95
20 EFFECT OF HYDROMULCH LAYER ON TEST CROPS 97
21 RANDOMIZED PLOT DESIGN FOR BULK MULCHING
EXPERIMENT 99
22 STRAWBERRY AND RASPBERRY PLOTS SHOWING
ENCLOSURES AND SLUDGE DEPTHS 101
23 STRAWBERRY AND RASPBERRY PLOTS SHOWING
ENCLOSURES AND SLUDGE DEPTHS 102
24 MOREL MUSHROOMS FOUND GROWING ON SLUDGE
PLOTS 104
vii
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TABLES
No. Page
1 Average Sludge Properties—Various Samplings 10
2 Ash Content of Sludge Samples 11
3 Elemental Analysis of Ash Samples 12
4 Primary Treatment Plant Operating Data 22
5 Operating Costs for Incinerating Primary
Treatment Plant Sludge 23
6 Maintenance Downtime—Equipment Evaluation 24
7 Particulate Efficiency Tests on Incinerator
Scrubber 27
8 Particulate Emissions on Incinerator Scrubber 28
9 Material Balance Data--Measured Quantities 30
10 Material Balance Data—Calculated Quantities 31
11 Hog Fuel and Sludge Properties—Port Townsend
Trial 34
12 Furnace Operating Data—Camas Sludge and Port
Townsend Hog Fuel Burning Trial at Port
Townsend 35
13 Hog Fuel and Sludge Properties--Camas Trial 37
14 Furnace Operating Data—Camas Sludge and Hog
Fuel Burning Trial at Camas 38
15 Cost of Pressing^ Burning Sludge in Camas
Hog Fuel Boiler 4o
16 Reduction of Sludge Volume by Dewatering
Steps 41
17 Estimated Cost of Pressing and Semi-Drying
Sludge 44
18 Operating Costs for Baling Semi-Dried Sludge 45
viii
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Mo. Page
19 Cost to Transport Sludge—Dry Ton Basis 46
20 Microbial Activity in Clay and Sandy Soil
After 120 Days Incubation 56
21 Treatment Ranking Using Duncan's New
Multiple Range Test 58
22 Experimental Design for Sludge Disposal
Field Trials 64
23 Statistical Ranking According to Duncan's
New Multiple Range Test for Corn Yield,
Tolerance Design for 1970, 1971, 1972 69
24 Statistical Ranking According to Duncan's
New Multiple Range Test for Bean Yields,
Tolerance Design for 197P, 1971, 1972 69
25 Summary—Tolerance Design 70
26 Effect of Sludge on Bean Maturity Rate When
Grown on Tolerance Plots 74
27 Statistical Ranking According to Duncan's
New Multiple Range Test for Corn Yield,
Yearly Amendment Design for 1970, 1971, 1972 76
28 Statistical Ranking According to Duncan's
New Multiple Range Test for Bean Yields,
Yearly Amendment Design for 1970, 1971, 1972 76
29 Summary—Yearly Amendment Design 77
30 Total Quality Scores of 1972 Corn and Bean
Crops on Disposal Design Plots 80
31 Effect of Clarifier Sludge on Corn and Bean
Yield in Field Plot Disposal Studies 8l
32 Statistical Ranking According to Duncan's
New Multiple Range Test for Corn and Bean
Yield--Disposal Design for 1970, 1971, 1972 82
33 Effect of 8 and 30 Months Residence of
Sludge Amendments1 on Occurrence-of Surface
Fungal Growths 84
ix
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No.
34 Ash and Volatile Solids Content of Sludge
Amended Soils 85
35 Application on Hydromulch Plots 89
36 Hydromulch Application and Efficacy Rating 92
37 Effect of Hydromulch on Tomato Yield 9&
38 Raspberry and Strawberry Yield on Hydromulch
Plots 98
39 Summary of Strawberry and Raspberry Yield
Data Under Bulk Mulch Conditions 100
40 Comparison of Materials for Oil Spill Clean-up 107
4l Ensilage Mixtures for Cattle Peed Studies 108
42 Silage Study 110
43 Grain Consumption and Weight Gains or Losses
for Dairy Steers 111
44 Comparison of Plant Growth in Standard
Synthetic and Sludge-Based Potting Media 115
45 Influence of Sludge on Control of Tomato
Root Knot Nematode 116
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SECTION I
CONCLUSIONS
1. Sludge properties vary considerably, but can be
characterized for disposal by frequent samplings and tests
such as Canadian standard freeness, ash content and fiber
size distribution (fiber fractionation). Generally, all
relate to the types of pulps and paper products being
manufactured. Elemental analyses of the ash reveal that
the inorganic portion of the sludge originates from clay,
silt, and sand, carried by wood mill effluent, and from
various additives required for paper making.
2. Disposal of primary treatment plant sludge from an
integrated pulp and paper mill can be accomplished by an
air-entrained incinerator. Over a 3 year period, operating
costs for incinerating sludge were $9.78-11.68 per ton for
a 20,000 ton/year plant. Plant capital cost (1968-1969
basis) was $350,000. Total disposal costs, including
primary treatment (clarifier and filter operation) were
$12.84-14.6o/ton. Maintenance cost was almost 1/3 the
operating cost. Tests show that the system can meet air
pollution standards for a waste material incinerator with
a wet fan-type dynamic scrubber made of stainless steel.
Material balance data around a sludge dewatering device
requires frequent measurements of consistencies and the
measurement of one flow to or from the device.
3. Pressed and fluffed primary treatment plant sludge can
be burned in a steam generating boiler with hog fuel.
There should be minimum effects on the operation if sludge
content of the fuel mix is no more than 5$. Reduction in
thermal efficiency of the boiler is related to the higher
ash content and lower calorific fuel value (of the organic
portion) of sludge, both compared to hog fuel. There would
be an approximate $1.50/ton savings by burning sludge in a
hog fuel boiler over burning it in a separate incinerator
with no heat recovery. Part of this savings could be
offset because the boiler would have to be cleaned more often,
due to ash accumulation.
4. Prom a primary treatment plant, sludge can be prepared
for disposal as a dewatered material at about 20$ solids
content, or as a pressed material at about 38$ solids
content. Semi-drying sludge to 77$ solids, followed by
baling, densifies the sludge to about 34 Ib dry material/
cu ft. This is triple the solids density of either dewatered
or pressed sludge.
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The cumulative costs per dry ton of sludge for dewatering,
pressing, semi-drying and baling are respectively $3.06,
$7.383 $13.86 and $19.89.
Hauling costs are dependent upon hauling distance, sludge
consistency and method of transport. Such costs were
found to vary from $l4-17/dry ton for hauling bulk,
pressed and fluffed sludge a short distance to $49/dry ton
to haul the same type of sludge about 250 miles by truck.
These costs do not include selling costs, profit or
special handling charges.
5. Soil respirometer experiments showed that extensive
sludge breakdown was obtained when levels of sludge were
added to nitrogen containing clay soil. In nitrogen
deficient sandy soils supplemental nitrogen was necessary
to obtain significant sludge decomposition. Additional
nitrogen was needed in both soils to optimize sludge
utilization when high levels of sludge were added.
6. Sunflower plant growth responses in sandy and clay
soils amended with sludge and nitrogen were studied in
greenhouse experiments. Amendments of sludge and nitrogen
improved sandy soil more than clay soil as shown by
increased sunflower yield. For example addition of 100
tons/acre (T/A) sludge to clay soil with supplemental
nitrogen caused a 1.7 fold increase in sunflower yield.
With sandy soil the same treatment resulted in a 2.7 fold
increase in yield.
7. Large amounts of sludge were readily degraded by mixing
into soil. After three years decomposition, plot levels
decreased from the initial two foot level to a level almost
equal to control plots not receiving sludge. Volatile
solids and improvement in yields of corn and beans were
obtained with high sludge incorporations which were
evaluated under the tolerance design. Amendments of 100
and 200 T/A did not adversely affect corn and bean yields
the following crop season provided supplemental nitrogen
was added to satisfy both plant and microbial requirements.
When 400 and 600 T/A sludge additions were allowed to
decompose without supplemental nitrogen for at least a year,
test crops showed increased yield, earlier maturation and
reduced irrigation requirements.
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8. Grass plantings by the hydromulch process indicate
that pulp and paper mill sludge or a mixture of sludge and
bark is equivalent to the wood fiber product currently used
as a mulching agent. The lower freeness or drainage rate
of sludge over wood fiber allows application to be made at
a higher solids content. The cost of a delivered semi-
dried bale of sludge in a local area should make sludge
or sludge-bark mixtures competitive products.
9. Hydromulching and bulk mulching of raspberries,
strawberries and tomatoes caused a reduction in weed
activity. However, with increases in sludge depth,
decreases in crop yield were observed.
10. Morel mushrooms well in excess of natural occurrence
were observed growing on various sludge amended plots in
the spring of 1971 and 1972. All attempts to grow these
mushrooms by design were unsuccessful.
11. Dried, oil-treated sludge can be used as an oil
absorbing material for oil spill clean up. However, on
basis of cost and storage problems, it does not appear
competitive with other marketed materials.
12. Sludge was not toxic to ruminants when used as a
feed supplement at levels up to 15$ of the grain ration.
It has a very low feeding value since the test steers
were observed to lose more weight as the percentage of
sludge was increased in place of corn.
13. Dried sludge has application as a bedding material
for dairy cattle. It readily absorbs liquids and is
competitive to shavings which are becoming increasingly
more costly and difficult to obtain.
14. Sludge-perlite (1:3) and sludge-vermiculite (1:1)
mixtures were satisfactory potting media for containerized
production of several plant species. Douglas fir responded
well in a mixture of equal portions of sludge and bark.
All two-component sludge mixtures were noticeably improved
as potting media with addition of river sand.
Root knot nematode galls on tomato transplants were
markedly reduced by incorporation of sludge in nematode
infested soil at rates equivalent to 100 and 200 T/A.
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SECTION II
RECOMMENDATIONS
High maintenance costs in the incinerator were caused by
the abrasive action of high ash content sludge on various
pieces of equipment and ducting. To reduce these costs,
affected areas in equipment should be modified or made
more resistant to this abrasive action. Reduction of
abrasive material may be accomplished by treatment of
effluents containing high levels of inorganics. Considera-
tion may also be given to the development of high volume
centrifugal cleaners for de-ashing effluents or high
consistency cleaners for processing low consistency sludge.
Disposal of large quantities of sludge was found to be
feasible under field conditions in a clay soil. Similar
evaluation is needed in sandy soils to not only determine
increase in soil productivity and tilth, but to also study
sludge effect on water retention and sand stabilization.
Preliminary experiments on use of sludge as a cattle
bedding material showed promise. There is a potential use
of sludge as bedding in place of more expensive and less
available wood shavings. The possibility of using sludge
as a poultry litter absorbent has been suggested and
requires evaluation.
The proliferation of edible "morels" in sludge amended
plots was found to be extremely interesting. Answers to
cause could easily found an industry for growing morels
which to date have not successfully been artificially
produced.
Major utilization of sludge would result from development
of sludge containing "synthetic soils" for use in contain-
erized crop production. Favorable results obtained in
greenhouse studies show potentiality for sludge use in
soil mixes. Future work should include evaluation of
various synthetic mixes and test species representing the
spectrum currently grown in containers.
Observed control of root-knot nematode by sludge incorpora-
tion indicates need for further and more extensive study.
Sludge additions to soil containing other soil borne
parasites or pathogens may be worthy of investigation.
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SECTION III
INTRODUCTION
Most pulp and paper mills in the United States today
provide primary treatment for the removal of settleable
solids from their effluents. Disposal of the resultant
solids presents a problem facing the industry.
Initially, land storage and land fill within a short
distance of the mill were used for sludge disposal.
However, since the material dried and decomposed slowly,
this approach at best was only a temporary expedient.
Although by-product utilization presents some possibilities,
contamination and extreme variability of product mitigates
against extensive development of markets.
Burning of sludge in hog fuel power boilers is being
practiced at a number of mills, but there is little
reported data and information on this method. Information
on the effect of sludge upon steam generation and atmospheric
emissions has not been available. Burning of sludges in
specially designed incinerators is widely used for domestic
wastes and is used at several paper mills (1).
Sludge utilization as an agricultural amendment presents
a potential for large scale sludge disposal either by
incorporation into the soil or as a mulching material.
Since many pulp and paper mills are located in areas
accessible to rather large tracts of suitable agricultural
land, development of this disposal method appears to have
considerable merit.
Early in 1968 Crown Zellerbach Corporation received a
research and development grant from the Environmental
Protection Agency for a project to be conducted at the
company's Camas Mill. The study was designed to study
four different methods of sludge disposal with the
objective of obtaining sufficient information and data
for the design of full scale disposal systems. The
methods of sludge disposal investigated and reported in
this paper were: (1) incineration in an air entrained
dryer-incinerator, (2) burning in hog fuel boilers,
(3) incorporation into soil as an amendment, and (4)
hydromulching for soil stabilization.
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SECTION IV
SLUDGE CHARACTERISTICS
In considering the various possibilities for disposing of
pulp and paper mill primary treatment plant sludge, the
properties related to disposal should be characterized.
Basically, the sludge is a fibrous material, and so
Canadian standard freeness, ash content, and fiber size
distribution (fiber fractionation) are logical properties
to evaluate. The various strength tests, associated with
pulp and paper making fibers, would only have meaning if
the sludge were screened and cleaned. In this case, the
sources contributing to the sludge and the type of mill
generating the material would affect the feasibility of
fiber recovery. Source of sludge for this project is an
integrated pulp and paper mill, producing bleached kraft
and sulfite grades. Table 1 gives average sludge properties,
taken during five different sampling periods.
During 1968, samples were taken of the primary treatment
plant coil filter cake, going to land fill. This was
prior to the building of the air-entrained incinerator.
These sludges could be characterized by high ash, low
freeness, and high amounts of -150 mesh size solids.
Improvements in the wood mill effluent grit collector and
diversion of a mill parking lot storm sewer into a city
storm sewer lowered the ash content, raised sludge freeness,
and lowered the amount of -150 mesh solids. The range of
property values has also tended to decrease over the period
of treatment plant operation. This is somewhat evident
in the range of ash content values shown in Table 2.
Again referring to the previous table, the data do show
that removing wood mill effluent from the primary treat-
ment plant causes a decrease in ash content. A special
project done by the mill indicated that almost 1/2 of
the ash in the sludge comes from the wood mill. Also,
about 70$ of the grit, or abrasive material in sludge ash,
is from wood mill effluent. The elemental analyses of
sludge ashes were determined spectrographically by the
State of Oregon, Department of Geology and Mineral Resources
and are shown in Table 3.
9
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TABLE 1
AVERAGE
Canadian
Sample Standard
Date Freeness, cc
Feb.-
Mar. 3
1968* 209
June-
July,
1968** 370
o Au§- ^»
1970 380 '
Sept.
13-15,
1971 621
Nov. 25-
Dec. 26,
1972 556
SLUDGE PROPERTIES— -VARIOUS SAMPLINGS
% Ash,
O.D. Fiber Fractionation^ % on Mesh
Basis 14 20 35 e>5 150 -150
26.5 9.6 7.8 10.4 9.3 8.0 54.9
29.7 10.4 8.9 9.4 7.9 8.1 55-3
17.4 , 12.6 11.9 12.1 9.6 7.6 46.2
20.7 13.7 11.1 10.4 7.4 9.8 47.6
19.0 19.6 10.7 10.9 10.6 9.4 38.8
*Average of 54 samples of filter cake.
**Average of 28 samples of filter cake.
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TABLE 2
ASH CONTENT OF SLUDGE SAMPLES
Sample Source,
Number , Period
Filter Cake,, 54,
2/1/68-3/17/68
Filter Cake, 28,
6/5/68-7/2/68
Press Cake, 25,
Vl/7 0-6/2 3/70
Press Cake, 5,
8/17/70-8/21/70*
% Ash,
Average
26.5
29.7
26.5
18.5
O.D. Solids
Minimum
10.3
15-5
19.6
16.5
Basis
Maximum
55.1
41.3
35.4
22.4
Press Cake, -,
9/13/71-9A5/71
Press Cake, 12,
11/25/72-12/6/72
20.7
19.00***
*Wood mill effluent diverted to alternate settling
pond.
**Composite of samples taken over the period.
***Samples composited for ash determination.
11
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TABLE 3
ELEMENTAL ANALYSIS OF ASH SAMPLES
Sample Source
and Date Over 10$ 1$-10$ 0.19&-15&
Coil Filter -
2/1/68-3/17/68
Coil Filter -
6/5/68-7/2/68
Press Cake -
4/1/70-6/23/70
Si
Si
Si,
Al
Al,
Na,
Ti
Al,
Ca,
K,
Fe,
Ca,
Ti
Fe, Mg, Mn
K
Fe, Mg, Mn
Na,
Ti
Mg, K
Na,
0.0156-0.1^
Pb,
Sr
Ba,
Sr
Mn,
Cu,
Sr
Ba,
Pb,
Pb,
Ba,
0.001^-0.01^
Zr,
Cr,
Ni,
Zr,
Mo,
T\T '
Ni,
Zr,
Sn,
Cu,
B
Cr,
Cu,
Cr
Below
0.001$
--
—
Ni
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The high amounts of silicon, aluminum, potassium, and iron
would confirm the presence of mud, clay, and silt brought
in with logs to the wood mill. They enter the effluent
from the log washing and hydraulic barking systems. Much
of the inorganics originate from materials, such as alum,
clay, silicate, and other additives, used in various
specialty grades in the paper mill. Summarily, the type
of operations carried on by the mill will affect sludge
properties.
13
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SECTION V
INCINERATION—AIR ENTRAINMENT
The EPA grant to Crown Zellerbach Corporation shared in
the expense of building an air-entrained incineration
plant for the disposal of sludge from the Caraas pulp and
paper mill primary treatment plant. The existing facility
consisted of a 330 ft diameter clarifier which delivers an
underflow sludge at 2-6$ solids content to two 11 ft
diameter by 10 ft wide coil filters. These further dewater
the sludge to 18-22$ solids. Prior to building the disposal
plant, the filter solids were conveyed to land fill. Figure
1 shows the original primary treatment plant and Figure 2
shows the air-entrained incinerator.
The air-entrained system flow sheet, shown in Figure 3,
starts with a V-type press which expels liquid from the
sludge to increase the solids content to 37-40$. The
pressate liquid is returned to the clarifier. From the
top of the press, the press cake is discharged to a screw
conveyor which transports it to a fluffer. This is a high
speed hammer mill which breaks up the cake for better
drying and incineration. Material then drops into the hot
gas stream from the incinerator to be carried up through
the dryer. This is a vertical conical shaped vessel with
two necked-in sections in the upper part. In each of the
sections there is a velocity control cone on a central shaft
which can be raised or lowered to alter velocity and reten-
tion time in the dryer. Dried material and conveying gas
are separated in a cyclone. The gas is drawn through all
this process by a large induced draft fan. Water is sprayed
into the fan to scrub particulate, and then the water
containing particulate, is separated from the gas in a
cyclone. Gas is discharged to the atmosphere.
Dried material at 70-85$ solids content drops out of the
cyclone through a rotary air lock valve into a stream of
conveying air. This stream carries the sludge into the
upper part of the cylindrical shaped incinerator where
it enters centrifically and burns. Natural gas is burned
with its own combustion air in the lower part to heat up
the incinerator on start-up. When sufficient heat is
generated from sludge combustion to support burning
(autogenous reaction), then gas use is limited to maintain-
ing burner control only. At times, gas is burned to
furnish supplementary heat if the fuel value of the sludge
15
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FIGURE 1. PR I MARY TREATMENT PLANT SHOWING SLUDGE DISPOSAL AREA.
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w^
FIGURE 2. AIR ENTRAINED INCINERATOR-SIDE VIEW.
17
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CLARIFIER
OVER-
FLOW
TO
LANDFII
S BURNER
PRESSED-FLUFFED SOLIDS
INCINERATOR DRY SOLIDS SCRUBBER
TO CLARIFIER *
AIR
LOCK
VALVE
ASH TO LAND FILL
FIGURES. AIR-ENTRAINED INCINERATOR
^
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is low. Secondary air enters the incinerator tangentially
above the gas burner. Ash drops out of the bottom onto a
water cooled metal chain drag conveyor. Water is also
sprayed onto the ash to cool it prior to its transfer to
a rubber conveyor belt, going to land fill. By a transfer
chute, sludge from the coil filter can go to land fill on
this belt when the incinerator is down.
For many of the disposal methods investigated, large
amounts of pressed and fluffed sludge were taken from the
system. This could be done by not running the fans, dryer,
and incinerator. A flange is removed from under the
fluffer, and sludge falls onto a portable conveyor which
can be elevated to take the sludge up into a dump truck
for transport to the site of use. Most of the sludge for
the experimental farm and for the burning trial in the
Camas hog fuel furnace was obtained this way.
A short conveyor and silage blower were used to fill chip
truck trailers for the hog fuel trial at our Port Townsend
kraft mill located in the State of Washington. Figure 4
shows a flow sheet which would be used by mills for
disposing of sludge by burning in hog fuel furnaces.
Smaller amounts of coil filter sludge at 18-22$ solids
were obtained for some uses. The first farm application
was collected by using a front end loader and dump truck
to remove material from the land fill area. This method
was not used after start-up of the incinerator in 1969.
Only small amounts of dried sludge at 70-85$ solids can
be obtained during operation of the incinerator by drawing
them off with a vacuum source from a port in the material
conveying duct to the incinerator. It is possible to
operate the system as a dryer by burning only gas, and
removing dried sludge from below the rotary air lock valve.
This system is shown in Figure 5.
In disposing of paper mill primary treatment plant sludge
by incineration, the objectives were to obtain the operating
costs, note any operational problems, and to determine
whether the process would meet emission standards set for
air, solid waste, and water effluent. All operating data
on the plant were logged, and the air-entrained incineration
system was given a separate account number so that all
costs could be tabulated. The basic data given in this
report were accumulated from monthly summary sheets prepared
19
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CLARIFIER
OVER-
FLOW
Mill
ro
o
TO
LANDFILL
HAUL OR CONVEY
HOG FUEL
FURNACE
FIGURE 4. PRESSED SLUDGE-BURN WITH HOG FUEL
-------
CLAR I FIER UNDERFLOW
THICKENER
TOCLARIFIER^
ID
ro
H
FLUFFER
AIR
HEATER ~7
BURNER
CYCLONE
AIR
LOCK
VALVE
EXHAUST
INDUCED
DRAFT
FAN
IQHQG FUEL
="* FURNACE
OR BALER
CONVEYOR AIR FAN
COMBUSTION
AIR
FIGURE 5. DRY SLUDGE-BURN WITH HOG FUEL
-------
by both the operating and accounting departments of the
Camas Mill. All special testing and projects were under-
taken by personnel assigned from the Central Research and
Environmental Services Divisions of Crown Zellerbach
Corporation.
A summary of 3 years operation is given in Table 4.
TABLE 4
PRIMARY TREATMENT PLANT OPERATING DATA
Year
Total Tons Sludge to Plant
Total Tons Sludge Incinerated
Total Tons Sludge to Land Fill
-------
TABLE 5
OPERATING COSTS FOR INCINERATING PRIMARY
TREATMENT PLANT SLUDGE
Year
Tons Sludge Incinerated
Direct Costs, $
1. Operating Labor--
Ind. Fringe Benefit
2. Repair Labor--
1970 1971 1972
16,041 14,249 17,067
23,146 22,246 27,272
Ind. Fringe Benefit
3. Repair Materials
4. Misc. Supplies, Expense
5. Electrical Power
6. Natural Gas
Totals, $
Indirect Cost (20$ Labor), $
Fixed Costs., $
1. Depreciation,
10$ Cap. Cost
2. Taxes and Insurance,
1.85$ Cap. Cost
Totals, $
Return on Investment, 8$, $
Total Cost, $
Incineration Cost/Ton, $
Filtration Cost/Ton, $
Total Disposal Cost/Ton, $
7,610
46,901
—
6,120
10,005
93,782
6,151
35,000
6,470
41,470
28,000
169,413
10.56
2.76
13.32
20,488
30,536
89
4,915
10, 140
88,415
8,547
35,000
6,470
41,470
28,000
166,431
11.68
2.92
14.60
20,490
23,852
389
6,412
93489
87, 904
9,552
35,000
6,470
41,470
28,000
166,926
9.78
3.06
12.84
23
-------
The entire primary treatment plant and sludge disposal by
incineration system can be operated by one man per shift.
Labor cost is split 50-50 between each, and only the
incineration half is shown in Table 5. All controls are
centrally located, and the major pieces of equipment are
adequately instrumented. The operator is responsible for
sampling.various flows for consistencies. The whole
operation is supervised at the Camas Mill by the sulfite
pulp mill.
The major operating cost is maintenance, attributable to
wear caused by grit and ash in the sludge. Table 6 shows
a breakdown in hours of maintenance time on specific
pieces of equipment for the years 1971 and 1972.
TABLE 6
MAINTENANCE DOWNTIME—EQUIPMENT EVALUATION
Year 1971 1972
% of % of
Hours Time Hours Time
Conveyor and V-Press 187 11.26 218.5 12.44
Fluffer 74.5 4.48 87.5 5.04
Cyclone, Dryer, Rotary
Air-Lock Valve 136 8.18 257 14.64
Incinerator 4l8.5 25.19 275 15.67
Ash Conveyor 56.5 3.40 36 2.05
Scrubber and Its Fan 131.5 7.92 89 5.07
Other Fans 26.0 1.56 20 1.14
Instruments—Controls 173-5- 10.43 77.5 4.42
Misc. Downtime,
General Maintenance 458.5 27.58 694 39.53
Totals 1662.0 100.00 1754.5 100.00
The V-press required 11-12$ of the total down-time. The
conveyor chute to the press caused some early problems,
mainly due to plug-ups. These have been minimized by
redesign of the chute and better control on the V-press
inlet mechanism. Filter sludge now is automatically
transferred to the conveyor belt to land fill when the
24
-------
chute plugs, and this relieves the operator of a nasty
clean-up problem when plugging occurs. Press screens
show wear and must be changed several times a year*
There has been some maintenance on the eddy current press
speed control.
An important factor in drying and burning sludge is to
have the material from the press well fluffed or opened
up. This is done by dropping pressed sludge through a
fluffer, or hammer mill. In 1970, fluffer hammers were
replaced 44 times, and fluffer screens 12 times. This
was a major maintenance item. Use of hardened alloy
hammer tips and a reduction in ash content of the sludge
decreased hammer replacements to about once a month during
1971 and 1972. Screen replacements were down to one or
two a year.
High ash content of the sludge has contributed to erosion
of high velocity areas of the dryer, cyclone, and ducts
to and from them. Flatbacks have been installed at elbows
and places of wear. Wiper blades on the rotary air-lock
valve require frequent replacement.
Downtime on the incinerator has been for slag removal,
modifications to the ash discharge, and replacement of
refractory. The latter wears out by erosion in areas of
high velocity.
The other major item of maintenance has been the wet fan
dynamic scrubber and the cyclone separator, following the
fan. The original equipment was made of mild steel, and
the fan housing and separator body were coated with
asphaltum. Thickness gage tests showed wear in high
velocity areas. Corrosion tests also showed that mild
steel would corrode in this environment, but that 304
stainless steel would be satisfactory. All these items
have now been replaced with stainless steel, and maintenance
costs have been reduced.
Generally, an air-entrained incineration system can be
expected to have high maintenance costs due to high
temperature-high velocity gas and solids flows, and due
to the abrasive property of high ash sludge.
The current regulation on particulate emissions for
incinerators is 0.1 grain/standard dry cu ft gas at 70° F.,
corrected to 12$ C02. Due to velocity problems in the
-------
scrubber outlet stack, early tests had to be made by
measuring particulate to the scrubber and particulate in
the scrubber water. The difference was assumed to be
emitted to atmosphere. Results, shown in Table 7,
indicated that the system could meet the regulation.
More recent tests were conducted after the scrubber stack
was modified to give a better velocity profile. The
results in Table 8 are measurements being emitted to the
atmosphere. Both tests gave values below 0.1 grain/standard
dry cu ft, at 70° F., corrected to 12$ C02.
To satisfy both the operating division and the pollution
control authorities, one has to know both the flows and
amounts of solids in the streams going to and coming from
the various units in the system. Many of the streams
carry solids, and flows can be large. Selection of
methods for measurements should be both practical and
reliable. Consistency, or solids content, is normally
taken on all flows. Large liquid flows are usually measured
with weirs. Smaller streams, such as the filter filtrate
and press pressate could be measured with weirs, or
possibly orifices, if the flow is pumped. Attempts have
been made to measure slurry flows by counting the strokes
and knowing the displacement of positive displacement
pumps. This is not always reliable because solids can
lodge under check valve seats.
Dewatered solids are usually transferred from one piece
of equipment to another by belt conveyors. This offers
the possibility of measuring flows by the use of belt
weighing devices. Solids flow can be measured on a filter
drum by taking a measured area of the filter cake, and
relating the dry solids in it to the total filter mat.
This is determined by knowing the filter drum speed,
diameter, and width. Uniform cake thickness is assumed.
The primary treatment plant operator takes consistencies
on the following streams:
Clarifier Influent
Clarifier Effluent
Sludge to Filter
Filter Cake
Filtrate
Press Cake
Pressate
26
-------
TABLE 7
ro
PARTICULATE EFFICIENCY TESTS ON INCINERATOR SCRUBBER
Test
No.
1
2
3
Scrubber
Flow, ACFM
22,530
22,530
22,230
Temp . ,
Wet
Bulb
237
237
275
°F.
Dry
Bulb
142
142
140
Particulate,
Ib/hr
In Out*
13.4 0
16.0 0.6
19.63 3.26
Emission,
Grains/Std.
Dry Cu Ft
0
0.0176
0.107
Scrubber
Effic.,
%
100
96
83.4
^Measured in scrubber water discharge and subtracted from inlet particulate.
**Corrected to 14.7 psia, 12$
-------
ro
oo
TABLE 8
PARTICULATE EMISSIONS ON INCINERATOR SCRUBBER
Test
No.
1
2
Scrubber
Plow. ACFM,
70° F.
32,650
33,300
Gas
Temp. ,
117
'117
Duct
Veloc. ,
fps
4-7.0
48.3
Carbon
Dioxide
2.5
2.0
Wate r
Vapor
7-3
6.3
Particulate,
Gr/Std Dry
Cu Ft, 70° P.*
0.051
0.066
•^Corrected to 14.7 psia, 12^
-------
Clarifier effluent is measured by a Parshall flume, and
this is assumed to be practically the same as the influent.
A flow pipe and V-notch weir were built to measure pressate
flow, and this can be measured. The operator also measures
sludge flow by taking V by V filter cake samples off
the filter drum. Prom all these data, all flows can be
determined by using the MATERIAL BALANCE FORMULA, given in
Figure 1A in the Appendix.
For a period of 5 days, extensive samplings and data were
taken to check the reliability of testing procedures.
The regular test data taken by the primary treatment plant
operator were supplemented by numerous tests and readings
taken around the clock by project personnel. Measured
quantities are given in Table 9.
From these data, the calculated quantities of Table 10
were obtained.
Using the two manually measured or observed flows of
pressate and filter cake pads, the O.D. tons of solids
going to the incinerator (as press cake) were calculated.
The filter cake daily tonnages were consistently higher.
Differences between influent, effluent, and press cake
solids are assumed to be either positive or negative
accumulations in the clarifier. There are no definite
conclusions to be drawn about the accuracy of either
measurement for material balance data. The results point
out, however, that some flow within the system should be
continually measured and accumulated by an integrating
recorder to obtain meaningful data on the amount of solids
going through the disposal plant.
29
-------
TABLE 9
MATERIAL BALANCE DATA—MEASURED QUANTITIES
u>
o
Day Ending
Consistencies, %
Clarifier Influent
Clarifier Effluent
Sludge to Filter
Filter Cake
Filtrate
Press Cake
Pressate
Ash Content, O.D. Solids
Basis, %
Filter Cake
Press Cake
Incinerator Ash
Gal/Day to Clarifier x 1000
Pressate Flow, gpm*
Hours Incin. Operation
Gas Usage, cu ft/day
8/17/70 8/18/70 8/19/70 8/20/70 8/21/70
0.033
0.004
2.67
16.58
0.037
40.90
0.342
0.031
o.oo4
2.525
16.94
0.045
41.68
0.364
0.018
2.425
17.00
0.046
39-80
0.435
0.021
2.356
15.86
0.039
37.71
0.410
0.0295
0.0002
2.548
17.28
0.031
38.00
0.479
16.01
16.52
92.8
55,899
35
24
16,700
21.87
22.43
61.81
55,416
29.1
24
13,000
18.18
19.65
91.09
57,758
33.8
18
8,600
17.68
17.19
92.92
56,773
31.5
24
13,400
16.26
16.49
91.14
57,800
31.45
22.5
18,600
•^Calculated from weir readings on pressate flow.
-------
TABLE 10
MATERIAL BALANCE DATA—CALCULATED QUANTITIES
Day Ending
Solids in Influent, tons
O.D. Tons Press Cake*
O.D. Tons Press Cake**
Solids in Effluent, Tons
Accum. in Clarifier, Tons*
Accum. in Clarifier, Tons**
% Losses in Effluent
Lb Loss/1000 Gal.
Therms Gas Used/Ton Sludge
8/17/70 8/18/70 8/19/70 8/20/70 8/21/70
77.0
57.5
64.7
7.1
12.4
5.2
9.24
0.33
3.07
71.6
48.9
66.7
6.9
15.8
-2.0
9.68
0.35
2.81
43.7
44.0
49.9
10.8
-ll.l
-17.0
24.8
1.55
2.06
49.7
50.5
63.5
7.1
-7.9
-20.9
14.3
0.50
2.81
71.2
5^.5
60.7
4.8
11.9
5.7
6.77
0.23
3.60
*Calculated from weir flow readings, pressate cons.
**Calculated from 4" x 4" pad taken from coil filter, filter speed, filter
area, filter cake cons, (mill data).
-------
SECTION VI
INCINERATION— HOG FUEL BOILERS
Pressed and fluffed sludge was taken from the Camas Mill
primary treatment plant to the Port Townsend Mill for a
trial of burning with hog fuel in a steam generating dutch
oven furnace. Sludge was transferred with a silage blower
into chip truck trailers, transported to the mill and dumped
onto the purchased chips conveying system. A transfer
conveyor moved sludge from the chip area to an empty hopper
in the steam plant. Fuel mixes for burning were made by
taking relative amounts out of the sludge and hog fuel
hoppers with a scoop, operated from an overhead monorail
track. The actual ratios of fuel components were determined
by manual separation of sludge and hog fuel from composite
samples taken from the furnace feed chutes. Fuel usage,
steam production, C02 in the flue gas, and ash pit pressure
were monitored during the run.
For the hog fuel burning trial at Camas, pressed and
fluffed sludge was taken from the incineration plant by
the method of portable conveyor and dump truck. An area
adjacent to the hog fuel pile was used for stock piling.
Hog fuel is pushed into a trough, which is kept. filled
with fuel. Drag chains in the bottom of the trough move
the material against a dam, and this gives a continuous
uniform volume flow of fuel. At the point where the
material is transferred to conveyor belts, sludge was
manually shoveled onto the belt at a rate estimated to
give the desired proportion of sludge. This flow was then
taken to the furnace directly. The furnace was loaded for
10 minutes out of each hour, and a composite sample of
each load was taken for moisture, ash, and heating value
tests. The amount of sludge in each mix was calculated
by knowing the ash content of the sludge, the hog fuel,
and the fuel mix. An example of the method is given as
follows :
Sludge = A
Hog Fuel = 2.74$ Ash
Fuel Mix =3.64$ Ash
a = Fraction Hog Fuel
K = Fraction Sludge
a + b = ..
0.0274 a + 0.1968 b = 0.0364 (2
Substituting; (1-a) for b, and solving the second equation
gives a = 07947, and then b = 0.053, or the fuel is 94.7$
hog fuel and 5.3$ sludge.
33
-------
The objectives of the sludge-hog fuel burning trials were
the following:
a. Determine the ratio of sludge to hog fuel which
can be burned in a steam generating boiler.
b. Note the effects on operation and steam production.
c. Determine the cost of this method of disposal.
d. Note effects on smoke emissions to the atmosphere.
The trial at the Port Townsend Mill was primarily to test
this method of disposal in order to allow for future
planning. Hog fuel and sludge properties for this trial
are given in Table 11.
TABLE 11
HOG FUEL AND SLUDGE PROPERTIES—
PORT TOWNSEND TRIAL
Sludge Hog Fuel
O.D. Solids, % 37.25 56.75
Ash, O.D. Basis, % 19.68 2.14
Aver. Wet Density, Ib/cu ft 26.7 24.3
Heating Value, O.D. Basis, Btu/lb 6130 9250
These fuel properties are the normally expected values
except that sludge solids content is slightly lower than
average. It is interesting to note that the two materials
have similar bulk densities. This enabled the operator to
make fuel mixes fairly accurately by volumetric measurement.
Furnace operating data are shown in Table 12. The average
conditions in the boiler were set during the first 4 hours
of the run. Thermal efficiency of the boiler with hog fuel
has been assumed to be 58.2$. When sludge and hog fuel
were added, the early effects were an increase in ash pit
pressure on the forced air fan and a lowering of the
-------
TABLE 12
FURNACE OPERATING DATA--CAMAS SLUDGE AND PORT TOWNSEND
HOG FUEL BURNING TRIAL AT PORT TOWNSEND
oo
Ul
Period of Run, hr.
Tons Dry Fuel Mix/Hr
Sludge in Dry Fuel, %
Ash in Dry Fuel, %
Tons Dry Sludge Used/Hr
Dry Fuel Therms Input /Hr
Steam Prod., M Ib/hr*
Thermal Effic. of Boiler, %**
Tons Ash/Hr
COP in Flue Gas, %
Ash Pit Pres., " HpO
Reduction in Thermal Effic., %
Reduction in Dry Fuel Heat
Value, %
4
5.25
0
2.14
0
972
49.6
58.2
0.1124
8-12
0.2
_-
—
17
3.12
12.5
5.32
0.390
553
26.6
58.0
0.1660
6-8
1.15
0.3
4.3
12
2.50
22.3
6.04
0.557
42g
18.2
53.7
0.1511
6-8
1.20
7.7
7.6
4
2.75
0
2.14
0
508
19.8
47.2
0.0588
6-8
1.20
18.8
*Lb Steam (1000 Btu/lb), corrected for feed water temp., etc.
**Assumes evaporation of moisture in fuel and 1000 Btu/lb steam produced,
-------
content of the flue gas. This indicates that more air is
needed to burn the fuel. Upon continuation of the run at
the high sludge fuel content of 22.3$, the reduction in
thermal efficiency becomes proportional to the lower heat
value of sludge. The final portion of the run without
sludge shows that the accumulation of ash from the sludge
has given the furnace a residual of lowered thermal
efficiency and reduction in steam production.
In order to extend the information gained from the trial
at Port Townsend, a 4 day run of burning sludge-hog fuel
mixes was planned for a hog fuel boiler at Camas. This
provided a better opportunity to note effects on furnace
operation, steam production, and emissions of smoke to
the atmosphere. Sludge and hog fuel properties for this
trial are given in Table 13.
The furnace operating data for the Camas Mill sludge-hog
fuel burning trial is given in Table 14.
The amounts of sludge in the fuel were calculated by the
ash content method, described earlier in this section.
Gas is burned in the furnace as auxiliary fuel, and its
heat contribution in therms (100,000 Btu's) is included.
During daylight hours of the trial a trained observer
noted Ringlemann No. on the boiler stack emission. The
only value over 1.0 resulted from an overloading of the
furnace. As previously mentioned, the boiler was operated
by filling with fuel every 10 minutes out of each hour.
Results show that the reduction in boiler thermal efficiency
is related to the higher ash content and lower calorific
fuel value of sludge, compared to hog fuel. The latter
on an ash-free basis would be about 8100 Btu/lb for sludge
and about 9550 Btu/lb for hog fuel.
As the tons of ash accumulate in the furnace, the thermal
efficiency of the furnace also drops, and this is illustrated
to be true whether sludge has been burned or not (the data
taken on 11/3)• The conclusion from both the Camas and
Port Townsend trials is that if a high-ash sludge (approx.
20$) is to be burned in a hog fuel boiler, it should be
no more than 5$ of the fuel mix. Even at this low level,
based on ash accumulation and a 7 day furnace cleaning
cycle without sludge, the furnace would have to be cleaned
every 5 days.
36
-------
TABLE 13
HOG FUEL AND SLUDGE PROPERTIBS--CAMAS TRIAL
I. Sludge Sample, Collected 10/12/70.
O.D. Solids, % =38.3
Ash, O.D. Basis, % = 19.68
II. Heating Values on Sludge and Fuel Mixes, Btu/lb, O.D. basis.
Sludge collected on 10/12/70 6,500
Hog Fuel Mix 5-3$ sludge), day ending 10/15/70 9,118
Hog Fuel Mix 13.3$ sludge), day ending 10/16/70 8,835
Hog Fuel Mix 17.1$ sludge), day ending 10/17/70 8,831
Hog Fuel Mix 8.0$ sludge), day ending 10/18/70 9,030
III. Hog Fuel Properties
Day Ending 10/15 10/16 10/17 10/18
O.D. Solids, % 48.5 47.0 47-5 48.9
Ash, O.D. Basis, % 2.74 3.04 2.02 2.39
Heating Value, Btu/lb,
O.D. Basis* 9,270 9,200 9,320 9,250
*Calculated from hog fuel mix data.
-------
TABLE 14
FURNACE OPERATING DATA—CAMAS SLUDGE AND HOG FUEL
BURNING TRIAL AT CAMAS
CD
Day Ending
Tons Dry Fuel Mix/Day
Sludge in Dry Fuel, %
Ash in Dry Fuel, %
Tons Dry Sludge Used/Day
Therms Gas Used/Day
Therm Equiv.-Dry Fuel/Day
Steam Prod., M Ib/day
Thermal Effic. of Boiler, $**
Tons Ash/Day
Maximum Ringlemann No.
Reduction in Dry Fuel Heat
Value, %
Reduction in Boiler Thermal
Effic., $****
10/15
35.4
5.3
3.64
1.88
6,270
6,450
855
67.0
1.29
1.2***
1.6
1.6
10/16
39.4
13.3
5.25
5.24
6,410
6,970
866
65.3
2.07
0.7
4.1
3.9
10/17
41.7
17.1
5.04
7.12
5,560
7,370
833
65.4
2.10
0.7
4.9
3.8
10/18
36.4
8.0
3.77
2.91
5,575
6,575
782
64.8
1.37
0
2.2
4.7
11/3*
18.5
0
?
0
10,950
3,425
931
62.6
7
9
*Day before furnace cleaning.
**Assumes evaporation of moisture in fuel and 940 Btu/lb steam produced (feed
water temp. 258° F.).
***High Ringlemann No. due to overloading the furnace.
****Assumes thermal effic. with no sludge is 68.1$.
-------
A cost estimate has been made for disposal of sludge in a
hog fuel boiler. The bases for the estimate are given as
follows :
1972 Operating Costs — Assume 17,076 tons to boiler.
Plant cost for pressing sludge = $120,000.
Sludge contains 60$ water.
Dry fuel heating value = 6315 Btu/lb.
Steam cost $0.55/1000 Ib.
Hog fuel contains 52$ water.
Dry hog fuel heating value = 9250 Btu/lb.
Maintenance cost 30$ of total incineration cost,
same for miscellaneous supplies, expenses.
Power cost 40$ of total incineration cost.
Calculation
Difference in cost between burning one dry ton sludge
versus one dry ton hog fuel:
Loss in Btu value = (2000) (9250 - 6315) = 5870 M Btu
Added Water Evap. = (2000) (1050) (0.42) = 880 M Btu
Total Difference = 6750 M Btu
Loss/ton sludge, assuming steam @ 940 Btu/lb:
(0.55) (250) = $3.95Aon sludge
~~
The cost estimate for burning pressed sludge in a hog fuel
boiler assumes that the material can be furnished to the
boiler at no handling charge. This means that dewatering
and pressing facilities are located adjacent to the hog
fuel storage area, and that the two fuels can be blended.
Table 15 shows that there would be a savings of about
$1.50 by disposing of sludge in a hog fuel boiler over
incineration.
39
-------
TABLE 15
COST OP PRESSING, BURNING SLUDGE IN
CAMAS HOG FUEL BOILER
(Based on 1972 Operating Costs)
Direct Cost—Pressing Sludge $/yr. $/Ton
1. Operating Labor - Ind. Fringe Ben. 27,272 1.596
2. Repair Labor - Ind. Fringe Ben. 6,150 0.360
3. Repair Materials 7,lbO 0.419
4. Misc. Supplies, Expenses 117 0.007
5. Electrical Power 2,560 0.150
Totals, $ 43,259 2.532
Indirect Cost—Pressing Sludge
1. Mill Burden (20$ of labor) 6,684 0.392
Fixed Costs—Pressing Sludge
1. Depreciation, 10$ Cap. Cost 12,000 0.702
2. Taxes & Ins., 1.85$ Cap. Cost 23220 0.130
Totals, $ 14,220 0.832
Return on Investment, 8$ 9,600 0.562
Total Costs, Pressed Sludge, $ 73,763 4.318
Primary Treatment Plant Sludge Cost, $ 52,225 3.060
Loss in Fuel Value, Burning Sludge, $ 67,270 3.950
Cost to Burn in Hog Fuel Boiler, $ 193,258 11.328*
Cost to Incinerate Sludge, $ 219,151 12.84
*The contingency of more frequent furnace cleanings is not
allowed for in the estimate. Also, no cost is shown for
blending sludge into the hog fuel.
40
-------
SECTION VII
SLUDGE PROCESSING AND COSTS
Devices used for dewatering sludge from the underflow of a
primary treatment plant are filters and centrifuges. At
Camas a coil filter is used, which is a type of belt
filter. Its main advantage is that it does not blind due
to the continuous flexing of the layers of coils which
form the belt. Sludge generally comes off the filter at
18-22$ solids and is transferred by belt to land fill or to
a V-press. Filtrate is returned to the clarifier. The
press further dewaters the sludge to 37-40$ solids, and
pressate is also returned to the clarifier. The press
cake is conveyed to a fluffer which breaks it up and fluffs
it. This material can be flash-dried by dropping it into
a stream of hot gas and carrying it through a retention
vessel. It can then be separated from the gas and collected
at from 50-80$ solids. In dried form, the product can be
densified by baling.
At each stage of dewatering sludge, in addition to a rise
in solids content, there is a change in its density and a
change in the solids contained in a cubic foot of the
material. These figures are given in Table 16.
TABLE 16
REDUCTION OF SLUDGE VOLUME BY DEWATERING STEPS
Density, % Solids, % Dry Solids/
Dewatering Device Ib/cu ft Average cu ft Sludge
Filter Cake 67.5 20 10.8
Press Cake 30 38 11.4
Dryer and Baler 43.7 77 33.7
There is not much difference between the Ib dry solids/cu
ft of sludge in filter cake and press cake because press
cake is rather bulky. Attempts to bale and densify press
-------
cake were not successful as contained water creates a
continuous water phase which causes the bale to fall apart
when the baling pressure is released. Pressed sludge can
be bulk handled by air blower conveying, front end loaders,
clamshell scoops, etc. Filter cake sludge is a fairly
sloppy product which is hard to handle. For purposes of
disposal, semi-drying and baling should be considered.
Bales have been made successfully from sludge dried to
77-80$ solids content.
For all the stages of sludge dewatering, a figure of $3.06/
dry ton has been added as the cost of operating the
clarifier and coil filter. This requires one operator
on a half-time basis.
The degree to which sludge is dewatered and the form in
which it is transported will depend on its end use.
Whether it can be stockpiled or whether it can be used as
received will also affect its form and determine how it
is to be shipped. Pressed sludge is the most convenient
form because it is the easiest to handle.
The cost of pressing sludge, developed in the previous
section on disposing of sludge in a hog fuel boiler (see
Table 15), assumes an installed equipment cost of $120,000.
This includes a transfer conveyor, feed chute, press,
press cake conveyor, and fluffer. Power usage is estimated
to be 40$ of the power needed for the total disposal by
air-entrained incineration, and maintenance would be 30$
of that for the total plant. This brings the cost of
pressing sludge to $4.32/dry ton, or with the prior
dewatering cost, a total of $7.3b/dry ton.
The cost for semi-drying sludge has been estimated, based
on the following:
Dry one ton sludge from 40$ O.D. to 77$ O.D.
Drying efficiency of 70$.
Fuel cost @ $0.08/therm (100,000 Btu).
Assume maintenance 75$ of incineration cost.
Production of 17,067 tons/year.
Use 1972 incineration cost data.
Capital cost of plant is $300,000.
The capital cost of the semi-drying plant is less than the
incinerator because there would be no ash handling equipment,
-------
The following calculation is made to show the cost for
fuel used for drying:
Calculations
Natural Gas Cost/Ton Sludge:
Water removed/ton dry sludge -1.2 tons
(1.2)(2000)(1050) = 2520 M Btu Required
2520 4 0.70 = 3600 M Btu supplied
Cost = (3600)(0.08)(0.01) = $2.880/ton
The estimated cost of pressing and semi-drying sludge is
shown in Table 17. Semi-drying would be practical only if
sludge were to be made a product of commerce.
Attached to a plant for semi-drying sludge would be a
baling machine. This would operate continually with the
dryer, and so a full-time operator is provided. The cost
of baling sludge along with the drying cost is given in
Table 18.
Pressed and fluffed sludge can be conveyed or blown into
trucks or barges for hauling or transport. The unloading
facility would require special equipment, except for dump
trucks. A ground area with cover could be provided for
some storage.
Bales of semi-dried sludge could be transported by long-
haul trucks or barges. Bale weights might be 1000-1400 Ib
gross weight, requiring fork lift trucks or hoists and
slings for loading and unloading.
The costs to transport sludge on a dry ton basis are given
in Table 19. These estimates are based on costs incurred
in moving sludge for some of the large-scale disposal
projects conducted under this EPA grant. The cost for
barging was given by the Crown Zellerbach Traffic Department,
It should be emphasized that all the amounts cited herein
do not include selling costs, profit, or special handling
charges.
-------
TABLE I?
ESTIMATED COST OF PRESSING AND SEMI-DRYING SLUDGE
(Based on 1972 Operating
Direct Cost
1. Operating Labor — Ind. Fringe Ben.
2. Repair Labor — Ind. Fringe Ben.
3. Repair Materials
4. Misc. Supplies, Expenses
5. Electrical Power
6. Natural Gas
Totals, $
Indirect Cost
1. Mill Burden (20$ of Labor)
Fixed Costs
1. Depreciation, 10$ Cap. Cost
2. Taxes and Ins., 1.85$ Cap. Cost
Totals, $
Return on Investment, 8$
Totals, $
Primary Treatment Plant Sludge Cost, $
Costs)
$/Yr
27,272
15,380
17,880
292
6, 412
49,153
116,189
8,530
30,000
5,550
35,550
24,000
184,269
52,225
$/Ton
1.596
0.901
1.047
0.017
0.375
2.880
6.816
0.500
1.757
0.325
2.082
1.404
10.802
3.06
Total Cost of Semi-dried Sludge, $ 236,494 13.862
44
-------
TABLE 18
OPERATING COSTS FOR BALING SEMI-DRIED SLUDGE
Basis: 1972 production of 17,067 tons, one man/shift,
capital cost for baler of $68,000, installed.
Direct Costs $/Yr $/Ton
1. Operating Labor—Ind. Fringe Ben. 54,544 3.192
2. Repair Labor—
Ind. Fringe Ben. (4$ Cap.) 2,720 0.159
3. Repair Materials (4$ Cap.) 2,720 0.159
4. Electrical Power, 50 H.P. 1,000 0.059
5. Baling Materials, $1.00/ton 17,067 1.000
Totals, $ 78,051 4.569
Indirect Cost
1. Mill Burden (20$ of Labor) 11,453 0.671
Fixed Costs
1. Depreciation, 10$ Cap. Cost 6,800 0.398
2. Taxes & Ins., 1.85$ Cap. Cost 1,260 0.074
Totals, $ 8,060 0.472
Return on Investment, 8$ 5,440 0.312
Total Baling Costs, $ 103,004 6.024
Cost of Semi-dried Sludge, $ 236,494 13.862
Total Cost Semi-dried, Baled Sludge, $ 339,498 19.886
45
-------
TABLE 19
COST TO TRANSPORT SLUDGE—DRY TON BASIS
A. Long Distance Haul (500 miles round trip).
Long-Haul Truck
Capacity
Dewatered State of Sludge
Sludge Capacity., Dry Tons
Cost Transport/Dry Ton, &
Cost of Sludge/Dry Ton, $
4Q,000 IP Payload
Semi-Dried,
Baled
Pressed*
,
41.20
7.38
jt Total Delivered Cost Aon, $ 48.58
18.5
20.25
19.89
40.14
B. Short Distance Haul (20 miles round trip)
Dump Truck
Capacity
Dewatered State of Sludge
Sludge Capacity, Dry Tons
Cost Transport/Dry Ton, $
Cost of Sludge/Dry Ton, $
10-11 cu yd
Pressed
1.75
10.00
7.38
Semi-Dried,
Baled
Total Delivered Cost/Ton, $ 17.38
Barge
46^,000 cu ft
Pressed*
262
13.18
7.38
20.56
Semi-Dried,
Baled
850
6.48
19.89
26.37
Long-Haul Truck
4b",OOP Ib Payload"
Pressed*
9.1
6.82
7.38
14.20
Semi-Dried,
Baled
18.5
3.41
19.89
23.30
*Does not include cost of facility for unloading.
-------
SECTION VIII
LABORATORY STUDIES
Two soils were used for the respirometer studies to
determine decomposition rate of sludge material. One
soil was obtained about 8 miles north of Pasco, Washington.
This soil was characterized as a Rupert sand which is the
predominate soil of the Pasco area and is similar to a
Quincy sand. The other soil was obtained from a farm
located about 3 miles northwest of Camas, Washington. A
portion of this farm was leased for later field plot trials.
Soil from this area is characterized as being a Hesson
clay loam.
Soil moisture was determined by weighing samples before
and after 24 hours at 105° C. Water holding capacity or
saturation capacity of soil and sludge was calculated from
the quantity of water retained by samples in Gooch crucibles
after immersion in water and then allowed to drain to
constant weight in a moisture-saturated atmosphere. Ash
was determined by firing a weighed oven dry sample at
4-00° C. for 12 hours and calculating loss of volatile
material. Carbon and nitrogen analysis of sludge using
conventional methods was determined and calculated to have .
a C:N of 234:1.
An adaptation of conventional respirometer technique (2)
Was used to determine rate and extent of Camas sludge
decomposition. Respirometers^ as shown in Figure 69
consisted of pint milk bottles containing 200 grams (AD)
soil mixed with varying sludge concentrations with or
without supplemental nitrogen. Nitrogen additions were
in the form of ammonium nitrate. Water was added to the
mixture and maintained at 65$ of the moisture holding
capacity of soil and waste. Temperature was maintained
at 30° C. in the incubated cabinet.
All treatments were triplicated and bottle location was
randomized in the respirometer incubator. Sufficient air
pressure was maintained to establish a minimal positive
flow of air which passed through traps designed to scrub
the air clean of ambient C02. This flow flushed C02
formed by microbial decomposition of sludge into test
tubes containing approximately IN caustic. C02 concentra-
tion was then determined by standard titration procedures
47
-------
FIGURE 6. CARBON DIOXIDE RESPIROMETERS FOR
DETERMINING SLUDGE DECOMPOSITION RATE.
48
-------
using standardized IN HC1. Tubes were replaced before
caustic absorption capacity was exceeded with fresh caustic
tubes. COQ evolved was recorded on a cumulative basis.
The experiments were terminated after 120 days.
Because of space limitations two experiments were designed
so that sludge additions ranging from 50 T/A to 600 T/A
could be evaluated. In the first experiment sludge was
added to the two test soils at rates of 50, 100, 150 and
200 T/A. Nitrogen was supplemented to give carbon-nitrogen
ratios of 25:1 and 100:1. Controls covered sludge additions
without supplemental nitrogen and nitrogen additions
without sludge. Nitrogen amounts added were equivalent to
those involved with sludge levels at C:N ratio of 25:1.
In the second experiment sludge was added at rates of 100,
200, 400 and 600 T/A.
Data from the two experiments, which are detailed in
Tables I, II, III and IV in the Appendix, were combined
and are presented in Figures 7, 8, 9> 10* and 11.
Figures 7 and 8 depict decomposition rate as tons utilized
when sludge was incorporated into sandy and clay soil
with supplemental nitrogen. Figure 7 shows the sludge
additions as 50, 100 and 150 T/A and Figure 8 shows the
higher additions of 200, 400 and 600 T/A. Ordinates
differ between Figures 7 and 8. In Figure 7 the ordinates
show a possible maximum of 60 tons sludge utilized. In
Figure 8, which also depicts higher sludge additions, the
ordinates show a possible maximum of 280 tons sludge
utilization.
The graphs displayed in Figures 9 and 10 present some
interesting relationships in respect to sludge levels,
nitrogen requirement and soil type. For example, there
was sufficiently available nitrogen present in clay soil
to allow considerable breakdown of sludge when added at
50, 100, 150 and 200 T/A rates. At 400 and 600 T/A
additions supplemental nitrogen was required to enhance
decomposition. Conversely, with sandy soil, additional
nitrogen was needed at all sludge incorporations to obtain
significant sludge breakdown. It was interesting to note
with the sandy soil treatments that higher nitrogen additions
enhance sludge decomposition when sludge was applied at
the 50, 100 and 150 T/A rates. When applied at 200, 400
and 600 T/A rates, no significant differences were noted
in decomposition of sludge with the various nitrogen additions
-------
o
LU
M
CO
CO
60 -,
50 -
40 -
30-
20-
10-
0
M
O
ID
—l
CO
CO
o
60-
50-
40-
30-
20-
10-
0
SLUDGE: 50T/A
Clay
Soil
Sandy
Soil
C:N
C:N
30 60 90 120 Days
SLUDGE:
Sandy
Soil
100 T/A
C:N
30 60 90 120 Days
SLUDGE: 150 T/A
Clay
Soil
Sandy
Soil
25
0
100
30 60 90 120 Days
FIGURE 7. TONS SLUDGE UTILIZED AT VARIOUS LOADINGS AT DIFFERENT C:N RATIOS.
-------
Q
LU
M
CO
00
o
LU
M
O
ZD
—I
00
oo
O
280-i
240-
200
160-
120
80
40.
0
280
240,
200.
160
120.
80
40.
0
SLUDGE: 200T/A
Clay Soil
Sandy Soil
C:N
C:N
0
90 120 Days
SLUDGE: 400 T/A
Clay Soil
C:N
0
I i r
Sandy Soil
20
10
40
0
30 60 90 120 Days
C:N
,SLUDGE: 600T/AX*10
40
0
Sandy Soil
0
30 60 90 120 Days
FIGURE 8. TONS SLUDGE UTILIZED AT VARIOUS LOADINGS AT DIFFERENT C:N RATIOS.
-------
300-
270-
o 24°"
UJ
M
i
^^•J
h—
ID
UJ
0
O
CO
00
0
210-
180-
150-
120-
90-
60-
30-
0
o
t:
00
O
Q_
O
o
III
LLJ
o
s
UJ
O
UJ
Q_
60 -,
50-
40-
30-
20-
10-
0
Clay Soil
Sludge
T/A
50
Clay Soil
600
30 60 90 120
Days incubation
Sandy Soil
Sludge
T/A
600
400
200
100
150
50
Sandy Soil
30 60 90 120
Days Incubation
FIGURE 9. SLUDGE DECOMPOSITION-NO NITROGEN ADDED.
52
-------
rsi
CO
CO
o
CO
o
0.
o
o
uu
Q
LU
S
0.
300-t
270-
240-
210-
180-
150-
120-
90-
60-
30-
0
60-f
50-
40-
30-
20-
10-
0
Sludge
T/A
Clay Soil
Sandy Soil
Sludge
T/A
Clay Soil
Sandy
Soil
30 60 90 120
Days Incubation
FIGURE 10. SLUDGE DECOMPOSITION
NITROGEN ADDED.
30 60 90 120
Days Incubation
-OPTIMUM
53
-------
CO
O
Q_
^
O
O
UJ
O
50-
40-
30-
20-
10-
Clay Soil
200 400 600
Tons Per Acre
C:N
Sandy Soil
Sandy Soil
C:N
0
200 400 600
Tons Per Acre
FIGURE 1L SLUDGE DECOMPOSITION IN 120 DAYS
FOR SANDY AND CLAY SOIL
-------
Figures 9, 10 and 11 present information shown in previous
figures in a different fashion. They compare decomposition
rates on the ordinates as percent sludge decomposition and
as tons of sludge utilized in the test soils. Curves in
Figure 9 depict no nitrogen additions or controls, whereas
curves in Figure 10 were derived from treatments involving
optimum nitrogen additions.
Evaluation of data depicted in Figures 9 and 10 lead to
the following conclusions:
1. When data are observed with respect to amount of
sludge added to that decomposed, then with
increasing sludge amounts, up to and including
the 400 T/A addition rate, more was decomposed.
As shown in Figure 9 when sludge was added at a
rate of 400 T/A, about 120 T/A were utilized
after 120 days incubation. With the 50 T/A
addition less than 30 T/A were used. Effect of
nitrogen used to enhance sludge breakdown is
shown in Figure 10.
2. When data are reviewed in relation to completeness
of breakdown, which is shown in curves having
percent decomposition ordinates, the lower sludge
levels were more completely utilized in 120 days.
For example 50 T/A addition was about 55$ utilized
in 120 days in clay soil without nitrogen and about
62$ utilized in sandy soil with optimum nitrogen.
On the other hand, when sludge was added at a
400 T/A rate in clay soil without nitrogen about
26$ was utilized in 120 days and about 37$ utilized
in sandy soil with nitrogen.
Data in Figure 11 again demonstrates the necessity of
nitrogen supplement to enhance sludge disposal in the
nitrogen deficient sandy soil or when exceptional high
levels of nitrogen poor material, such as sludge, are
being disposed.
As shown in Table 20, microbial activity after 120 days
incubation of mixtures of test soils and various levels
of sludge and nitrogen in clay soil results in a more than
ten-fold increase in mold and bacterial numbers. This
was noted in the 400 and 600 T/A treatments with or without
nitrogen supplement. However, a far greater increase in
microbial activity was noted in sandy soil. Here, mold
was found to increase approximately 20 fold whereas
bacterial numbers increased from approximately 1,000,000/
gram soil to 563,000,000/gram.
55
-------
TABLE 20
MICROBIAL ACTIVITY IN CLAY AND SANDY SOIL AFTER 120 DAYS INCUBATION
VJl
o\
Sludge
Addition
Tons/Acre
0
100
200
400
600
100
100
100
100
200
200
200
200
400
400
4oo
400
600
600
600
600
Nitrogen
Addition
C:N
0
0
0
0
0
Clay Soil^
Microorganisms/gr
0
40:
20:
10:
0
40:
20:
0
40:
20:
10:
0
40;
20:
1
1
1
1
1
10:1
1
1
1
1
1
10:1
Molds
pH (1 x 10-3)
5.7 183
6.8 170
6.8 173
6.6 853
7.0 1876
6.8 170
6.5 430
6.5 320
6.9 276
6.8 173
7.4 220
6.8 135
6.8 233
6.6 853
6.8 540
7.1 733
6.9 873
7.0 1876
6.7 577
6.7 3417
7.2 870
Bacteria
(1 x 10-fe)
14
29
230
230
455
29
45
50
45
230
174
125
76
230
243
220
169
455
655
667
235
Sandy Soil
^lic roorganisms/gr
pH
6.8
6.9
7.3
7.3
6.9
6.9
6.9
6.9
7.6
7.3
6.4
7.0
7.5
7.3
6.8
6.7
7.0
6.9
7.2
7.4
7.8
Molds
(1 x 10"3)
7
93
58
66
25
93
93
115
73
58
40
440
16
66
185
78
42
25
148
103
110
Bacteria
(1 x ID'6)
1
26
23
69
239
26
240
242
200
23
394
106
162
69
393
217
342
239
317
563
400
-------
SECTION IX
GREENHOUSE STUDIES
Two air dry kilograms of Pasco sandy and Hesson clay soils
were mixed with sludge to give field additions equivalent
to 50, 100, 150, and 200 tons sludge per acre. Nitrogen
as ammonium nitrate was supplemented and evenly distributed
throughout sludge-soil mixtures in amounts to give sludge-
nitrogen C:N ratios, of 25:1 and 100:1.
Each of the mixtures were adjusted to 65 percent of their
moisture holding capacity. According to pot culture
technique of Stephenson and Schuster (3), aliquots of a
nutrient solution, without nitrogen,, but containing
essential elements for plant growth were added to each pot.
All treatments were triplicated and pot placement randomized
in the greenhouse. Ten sunflower seeds (Mammouth) were
pressed into the soil contained in two quart milk cartons
and covered to a depth of J inch. Milk carton height was
adjusted to one inch above soil level by trimming off
excess. Within a week of seedling emergence, plants were
selected for uniformity within each pot and culls removed
by cutting stems at soil surface.
Plants were watered on an individual pot basis whenever
soil surface appeared dry and leaves showed signs of
incipient wilt. Maintaining the sunflower test plants
under this water regime did not adversely affect plant
growth, but did minimize unwanted leaching losses of
water soluble components from the sludge-soil mixtures.
Above ground portions of test plants were harvested when
developing flower buds first became visible. Yield was
measured as fresh and dry weights. Test soils were removed
from their containers, freed of residual roots, pulverized
&nd replanted with sunflowers. A total of four crops were
grown in each container of soil. Nutrient solution was
applied to test soils at each planting. No additional
nitrogen was added after the first crop. Length of
growing period varied with season and ranged from 57 days
to 76 days.
Experimental design and ranking (4) of yield data are
shown in Table 21. Individual crop yields are shown in
Table V in the Appendix. Sludge amendments of 100, 150,
57
-------
TABLE 21
TREATMENT RANKING USING DUNCAN'S NEW MULTIPLE RANGE TEST
Sunflower Dry Weight—Grams
Ui
Treatment
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Sludge
Tons/A
0
50
100
150
200
50
50
100
100
150
150
200
200
0
0
0
0
Duncan's Ranking
Sandy Clay Sandy Soil
Clay Soil
Additional Soil Soil Treatment
Nitrogen Yield Yield No. Yield
0
0
0
0
0
25:
100:
25:
100:
25:
1.88 4.63 17 0.93
1.78 2.35 16 1,48
1.98 1.85 2 1.78
1.93 2.15 1 1-88
1.90 2.18 5 1-90
l 2.70 6.35 4 1.93
1 1.93 3.65 7 1.93
1 5.08 7.75 3 1.98
1 2.13 3.65 13 1.98
1 4.98 6.68 9 2.13
100:1 2.28 3.45 11 2.28
25'
100-
p
f-)
4
1 5.13 6.15 15 2.35
1 1.98 3.60 6 2.70
3.03 4.45 14 3.03
2.35 1.95 10 4.98
1.48 0.50 8 5.08
0.93 0.35 12 5.13
Treatment
No. Yield
17 0.35
16 0.50
3 1.85
15 1.95
4 2.15
5 2.18
2 2.35
11 3.45
13 3.60
7 3.65
9 3.65
14 4.45
1 4.63
12 6.15
6 6.35
10 6.68
8 7.75
(1), (2), (3) and (4) enuivalent nitrogen as added in treatments 6, 8, 10 and 12 respectively.
Non-bracketed means are significantly different at 5$ level.
-------
and 200 T/A in both soils in combination with supplemental
nitrogen at a C:N of 25:1 significantly improved sunflower
growth over that of controls. Growth of sunflower,
however, was markedly lower where sludge amendments were
made without nitrogen. Yields were not improved with
sludge addition and nitrogen at a C:N of 100:1.
Statistical comparison of growth curves in Figure 12 shows
the magnitude of difference between 25:1 and 100:1 C:N
ratios for the two soils.
The overall responses to treatments in sandy soil were
quite similar to those in clay soil. However the yield
levels were considerably different, i.e., mean yield in
control clay soil (no sludge — no nitrogen) was 4.63 grams 3
whereas in control sandy soil (no sludge — no nitrogen) it
was 1.88 grams. Incorporation of sludge at 100 T/A and
a C:N of 25:1 in clay soil increased mean crop yield to.
7.75 grams , a 1.7 fold increase. Conversely with sandy
soil receiving equivalent sludge and nitrogen, the increase
in yield was 5.08 grams or a 2.7 fold increase.
various levels of sludge were added to clay soil and
supplemental nitrogen provided, no significant differences
in crop yield were obtained even though these yields ranged
from 1.85 grams to 2.35 grams and were approximately one
naif the 4.63 gram yield obtained with control soil. A
similar crop yield reduction resulted when nitrogen was
added without sludge.
Sandy soil without sludge responded more favorably to
nitrogen additions than did the clay soil. In sandy soil,
as shown in Table 21, nitrogen additions to control soil
(treatments 14 and 15) significantly increased sunflower
yields. More nitrogen (treatments 16 and 17) decreased
yield.
Figures 2A, 3A, 4A and 5A in Appendix present photographs
°f each harvest before sunflowers were cut down, dried
and weighed. Numbers under each container correspond to
treatment outlined in the tables.
59
-------
1 7-1
C A
oo-
iES-
^^ VI
"*= 7
_2 3 -
Q.
2-
1 -
0
Means not followed by the same letter are significantly
different at 5% level.
SANDY SOIL
Control
C:N = 25:1
C:N = 100:1
No N Added
No Sludge
N • Same as (1)
0
50
100
150
200
to
E
Q.
^r
o
8 -
7
6
5
4
3
2 -
1 -
0
Control
CLAY SOIL
C:N = 25:1
C:N = 100:1
r Sludge
No N Added
d No Sludge
N = Same as (1)
50 100 150 200
Sludge Addition Tons/Acre
FIGURE 12. EFFECT OF NITROGEN ADDITION AND SLUDGE
ON SUNFLOWER YIELD.
60
-------
SECTION X
FIELD PLOT STUDIES
A five acre field about three miles from the clarifier was
leased for the study. Historically it was in permanent
pasture of grass and clover for ten years and of only fair
productivity. The Hesson clay topsoil and brown-yellow
silty clay subsoil of this area has a marked tendency
toward clod formation when depleted of organic constituents.
The field was plowed in July of 1969 to a depth of 6 inches.
During the summer and fall months the plots were periodically
disced to control weeds. Ninety-six plots, measuring 10
by 38 feet, were layed out with the long sides at right
angles to the slight slope of the field. Each treatment
was replicated four times and each plot was divided into
4 subplots to permit evaluation of nitrogen additions on
crop growth and sludge decomposition. Three rates of
nitrogen fertilization were used based on carbon:nitrogen
(C:N) ratios of 10:1, 50:1 and 100:1. The experimental
design,, location of randomized plots, position of subplots
with respect to nitrogen additions and crop locations as
well as row placement are shown in Figure 13. An aerial
photograph in Figure 14 shows plot location and alignment.
The rates and frequency of sludge application and the number
of seasons crops were cultivated are shown in Table 22.
The main disposal designs studied were: (A) Tolerance,
(B) Yearly Amendment and (C) Disposal.
The Tolerance approach to sludge utilization was planned
to determine the effect of a single incorporation of high
levels of undecomposed sludge on the 1970 crops of sweet
corn and snap beans. Recropping these plots in 1971 and
1972 was planned so that there would be a time interval
for disappearance of potential sludge induced phytotoxicity.
Sludge addition in the Yearly Amendment objective was made
in a manner simulating farmer use of crop residues or
cover crops. Beans and corn were grown on these plots
each of the three years.
The most efficient land use and maximum rate of sludge
disposal would probably be achieved under the Disposal
objective. Yearly sludge incorporation into these plots
was carried out over the three year period of the study
with test crops of beans and corn cultivated in the 1972
season only.
61
-------
A
B
C
D
22'
fai
CjN
A = 1:10
B = 1:50
C:N
C = 1:100
D = 0
ro
FIGURE 13. EXPERIMENTAL PLOT LAYOUT FOR SLUDGE UTILIZATION PROJECT.
-------
LO
-
FIGURE 14. AERIAL PHOTOGRAPH OF SLUDGE AMENDED PLOTS.
-------
TABLE 22
EXPERIMENTAL DESIGN FOR SLUDGE DISPOSAL
FIELD TRIALS
A. Tolerance - Add sludge once only, in fall; plant
crop each spring.
Split Plot C:N
Plot Addition,
No
1
2
3
4
5
6
7
8
B.
9
10
11
12
13
14
15
16
C.
17
18
19
20
21
22
23
24
Tons/Acre
0
200
400
600
0
200
400
600
Crop
Corn
Corn
Corn
Corn
Beans
Beans
Beans
Beans
Yearly Amendment - Add
each spring.
0
100
200
400
0
100
200
400
Disposal - Add
summer; plant
0
100
200
400
0
100
200
400
Corn
Corn
Corn
Corn
Beans
Beans
Beans
Beans
sludge
A B
Lbs N Lbs N
10:1
91.6
91.6
183.3
274.9
91.6
91.6
183.3
274.9
50:1
18.3
18.3
36.7
55.0
18.3
18.3
36.7
55.0
C D
Lbs N Lbs N
100:1
9.2
9.2 .
18.3
27.5
9.2
9.2
18.3
27.5
sludge each fall; plant
45.8
45.8
91.6
183.3
45.8
45.8
91.6
183.3
each fall;
9.2
9.2
18.3
36.7
9.2
9.2
18.3
36.7
work
4,6
4.6
Q P
^y * C—
18.3
4.6
4.6
9.2
18.3
in during
.0
0
0
0
0
0
0
0
0
crop
0
0
0
0
0
0
0
0
crop after 3 years.
Corn
Corn
Corn
Corn
Beans
Beans
Beans
Beans
45.8
45.8
91.6
183.3
45.8
45.8
91.6
183.3
9.2
9.2
18.3
36.7
9.2
I8i3
36.7
4.6
4.6
9 2
18.3
4.6
4.6
9.2
18.3
0
0
0
0
0
0
0
0
-------
Sludge for the initial amendments was collected after
dewatering by vacuum filter and stored adjacent to the
experimental plots in late spring of 1969. Application
and soil incorporation of this 20$ consistency sludge was
difficult. The capability of dewatering sludge to 38$
consistency was realized with installation of the inciner-
ator and Reitz press. The drier sludge was used for the
1970 and 1971 amendments and was far superior to the 20$
consistency material with respect to ease of handling,
application and incorporation.
Sludge incorporated in 1969 and 1970 equivalent to a total
of 800 T/A to the Yearly Amendment and the Disposal plots
altered their surface composition to essentially that of
sludge. The final sludge application scheduled for
September 1971 could not be made with power equipment as
the spongy or marsh-like consistency of the 400 T/A plots
would not support weight of the farm equipment. Therefore
the third 400 T/A amendment to Yearly Amendment and
Tolerance plots was canceled.
Except for the difficulties encountered in 1969 with
application and rotovation of the 20 percent consistency
sludge and those involving successive yearly additions of
400 T/A, standard farm equipment worked well in mixing
sludge with soil. Two tractors were used, one to pull an
International Harvester Corporation manure spreader and
the other, a 45 H.P. Ford diesel, with a Wagner loader
attachment, was used to load sludge on the spreader. The
Pord tractor was also equipped with a heavy duty E-60
Howard Rotovator.
Weight/volume relationships of the 20 and 38$ solids sludge
were used to determine the plot requirements. The 20$
solids required two and the 38$ solids required three
spreader loads to give a 100 T/A rate.
Uniform distribution of sludge was accomplished by repeated
passes over the length of the plot with no more than 2
spreader loads. The resulting 4 to 5 inch sludge layer
was then rototilled into the soil.
Plot perimeters were aligned and surfaces leveled by hand
tools and the initial 1/3 of the specified nitrogen was
applied in the form of 34$ ammonium nitrate. Subsequent
applications of nitrogen were made in February and late
65
-------
March. During the first year of study in which 10:1 C:N
ratios were part of the experimental design, the ammonium
nitrate was applied in four portions with the final portion
spread May 1. A 0-20-20 fertilizer application (N-P-K) at
a 500 pound per acre rate was made to all plots in line
with the general agricultural practices for farm land in
this area.
Weed growth during fall-winter fallow was controlled with
sprays of Paraquat CL at 2 quarts per acre.
Plots were rototilled as early in May of each year as soil
conditions would permit using a 4 H.P. hand operated
tiller. Use of the small rototiller was necessary for
cultivation of individual subplots to avoid intermixing
of subplots of different nitrogen levels. In 1969 only,
preplanting herbicide treatments were made on all plots
for weed grasses with Eptam 60 at 2 quarts per acre. An
additional preplant treatment of corn plots was made for
broadleaf weed control with Atrazine at 2.5 Iks per acre.
Uniform non-skip delivery of Tendercrop variety bean seeds
into furrows was accomplished with a planter made of a
plastic wide neck funnel inserted into a 3^ ft length of
3/4 in. electrical conduit. Golden Jubilee variety corn
was planted in hills about 1 foot apart using a commercial
hand planter set to deliver 3 to 4 seeds.
Plant stands were thinned when they were 3-4 inches high
to a spacing of 3-4 inches in the case of beans and 1 foot
spacing or 1 plant per hill in the case of corn.
Plots were irrigated at 10 to 12 day intervals using 7
overhead sprinklers each of which delivered about 5 gallons
per minute. Irrigation for 3-4 hours applied about 0.8 in.
water at which time the sprinklers were moved to the next
area. The need for water was determined by the condition
of soil in the control plots as the soil in these plots
was consistently depleted of moisture more rapidly than
sludge amended plots.
Weed growth during the 1970 growing season was minimal as
a result of preplanting herbicide treatments and discing
procedures. No special attention was given plots other
than irrigation as needed. Slight herbicidal damage to
corn in the form of leaf burn and stunting did occur and
66
-------
preplant chemical weed control measures were eliminated in
subsequent years. With no herbicide used prior to seeding
or as a pre-emergence treatment, weed growth in non-sludge
and low rate sludge plots was extensive even before
emergence of corn and bean plants. Hand cultivation and
between row low pressure spray applications of Paraquat CL
using a hand sprayer were effective control measures.
Herbicide was also applied to the perimeter of plots to
reduce mid and late season encroachment of weeds from turf
areas separating the plots.
Only mature pods and mature full ears were picked on the
first harvest date of each crop. The randomly occurring
unfilled ears of corn with less than 50$ kernel development
were not included in yield data of final harvest.
The influence of sludge amendments on corn and bean growth
was determined 1 month before harvest for each of the 3
crop years as Total Quality Scores (TQS). As shown on the
following page, the TQS is the sum of numerical ratings
assigned to five of the following growth criteria with a
maximum score of 20 indicative of near perfect growth and
development:
67
-------
Growth
Criteria
Numerical Rating
2
Seedling
Emergence3
95-
100
75-
94
50-
74
49
0-
24
General
Appearance
Very
Good
Good
Fair
Poor
Very
Poor
Color
Dark Light Yellow
Green Green Green
Yellow Chlorotic
Leaf
Abnormalities None
Few Moderate
Many
Very
Many
Average Crop
Height, cm
Corn
More
Than 200-
300 300
100-
200
50-
100
0-
50
Beans
More
Than
40
20-
30
10-
20
0-
10
Yields from subplots on the harvest dates were made in pounds
and tenths of pounds. A portable Horns beam scale was used
to weigh harvested crops contained in plastic bags.
TOLERANCE DESIGN
Plot Quality Evaluation, 1970
Detailed data concerning total quality scores and yields
are shown in Tables VI, VII, VIII in the Appendix for the
Tolerance Design portion of the field plot studies. For
convenience summaries of these data are given in Tables
23, 24 and 25.
68
-------
TABLE
23
STATISTICAL RANKING ACCORDING TO DUNCAN'S NEW MULTIPLE RANGE TEST FOR CORN YIELD,
TOLERANCE DESIGN FOR 1970, 1971. 1972
1970
Plot Sludge Nitrogen Yield
No. Tons/A Addition Lbs
2A 200 10:1 0
3A 400 10:1 0
4A 600 10:1 0
1A 0 91. 6# 1.9
4D 600 0 21.5
IB 0 18. 3# 22.8
3D 400 0 24. 7
4B 600 50:1 26.4
2B 200 50:1 32.7
1C 0 9.2# 33.5
4C 600 100:1 3^.5
3B 400 50:1 41.4
2D 200 0 46.9
3C 400 100:1 4?. 3
ID 0 0 55-5
2C 200 100:1 69.9
STATISTIC
1970
1971 1972
Plot Sludge Nitroge, Yield Plot Sludge Nitrogen Yield
No. Tons /A Addition Lbs No. Tons/A Addition Lbs
1A 0 91. 6# 1.5
IB 0 18. 3# 20.2
ID 0 0 26.3
1C ' 0 9-2# 27.3
2A 200 10:1 34.0
2D 200 0 34.8
2C 200 100:1 35.0
4A 600 10:1 35.7
2B 200 50:1 44.1
4D 600 0 46.4
4B 600 50:1 46.5
3D 400 0 47.3
3A 400 10:1 47.6
4C 600 100:1 49.3
3C 400 100:1 51.5
3B 400 50:1 52.9
TABLE 24
1A 0 . 91. 6# 12.6
IB 0 l8.3,f 25.7
ID 0 0 28.4
3D 400 0 28.9
2A 200 10:1 30.6
2D 200 0 32.7
1C 0 9-2# 33-3
2B 200 50:1 35.0
2C 200 100:1 39-0
3A 400 10:1 41.7
3B 400 50:1 42.8
3C 400 100:1 43.4
4c 600 100:1 45.6
4D 600 0 46.8
4B 600 50:1 48.6
4A 600 10:1 50.9
AL RANKING ACCORDING TO DUNCAN'S NEW MULTIPLE RANGE TEST FOR BEAN YIELDS.
TOLERANCE DESIGN FOR 1970, 1971, 1972
1971 1972
Plot Sludge Nitrogen Yield Plot Sludge Nitrogen Yield Plot Sludge Nitrogen Yield
So. Tons/A Addition Lbs Ho. Tons/A Addition Lbs No. Tons/A Addition Lbs
5A 0 91. 6#
7A 400 10:1
8A 600 10:1
6A 200 10:1 0
7B 400 50:1 1
8B 600 50:1 2
8D 600 0 2
5B 0 18.3# 3
7C 4OO 100:1 5
Sc 600 100:1 5
6B 200 50:1 5
7D 400 0 7
5C 0 9.2# 17
6D 200 0 21
6C 200 100:1 26
5D 0 0 32
0 5A 0 91. 6# 0.3
0 6A 200 10:1 0.3
0 7A 400 10:1 1.8
.1 8A 600 10:1 2.6
.4 5B 0 18. 3# 4.6
.7 5C 0 9.2# 13.1
.8 5D 0 0 17.4
.1 6B 200 50:1 18.4
.0 7B 400 50:1 19.3
.U 7D 400 0 20.1
.8 8D 600 0 20.1
.3 6D 200 0 21.2
.1 6C 200 100:1 23.4
.8 8B 600 50:1 24.4
.1 7C 400 100:1 26.8
.2 8c 600 100:1 27.4
5A 0 91. 6# 0.4
6A 200 10:1 0.9
5B 0 18. 3# 8.8
5D 0 0 17.9
5C 0 9.2# 22.2
7D 400 0 27.9
6B 200 50:1 28.5
7A 400 10:1 30.1
8A 600 10:1 30.5
7C 400 100:1 30.7
6C 200 100:1 31.2
6D 200 0 31.5
7B 400 50:1 33.7
8D 600 0 38.5
8B 600 50:1 39.1
8C 600 100:1 42.7
Any two values not bracketed by same line are significantly different; any two values bracketed are not significantly
different at 5# level.
-------
TABLE 25
Sludge
T/A
0
0
0
0
200
200
200
200
400
400
400
400
600
600
600
600
Nitrogen
Addition
Ibs N
91.6
18.3
9.2
0
CiN
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
SUMMARY — TOLERANCE DESIGN
Total Quality Scores
igfrg
0
14
15
18
2
16
18
12
0
12
16
9
0
12
16
7
Corn
Ig7_l
8
16
16
16
18
18
19
17
19
19
19
19
19
19
19
19
1972
7
14
17
16
18
17
17
16
18
18
17
16
20
20
20
20
igVo
1
9
11
17
6
12
14
10
0
10
12
9
0
11
11
8
Beans
1971 1972
3
10
14
15
6
17
17
17
16
17
18
17
16
19
19
18
Yield, Ibs/sub-plot
Corn
1970
1.9
27.8
33.5
55.5
0
32.7
69.9
46.9
0
41.4
47.3
24.7
0
26.4
34.5
21.5
1971
1.5
20.2
27.3
26.3
34.0
44.1
35.0
34.8
47.6
52.9
51.5
47.3
35.7
46.5
8:1
1972
12.6
25.7
33.3
28.4
30.6
35.0
39.0
32.7
41.7
42.8
43.4
28.9
50.9
48.6
45.6
46.8
Total
16.0
73.7
llo!2
64.6
111.8
1^3.9
114.4
89.3
137.1
142.2
100.9
86.6
121.5
129.4
114.7
M°.
0
3.1
17.1
32.2
0.1
5.8
26.1
21.8
0
1.4
5.0
7.3
0
2.7
5.4
2.8
Beans
Ml
0.3
4.6
13.1
17.4
0.3
18.4
23.4
21.2
1.8
19.3
26.8
20.1
2.6
24.4
27.4
20.1
Mi
0.4
8.8
22.2
17.9
0.8
28.5
31.2
31.5
30.1
33.7
30.7
27-9
30.5
39.1
42.7
38.5
Total
0.7
16.5
52.4
67.5
1.2
52.7
80.7
74.5
31.9
54.4
62.5
55.3
33.1
56 1 2
75.5
61.4
*Total quality scores not observed in 1971.
-------
Sludge amendments to field plots in the fall of 19&9 at
200, 400 and 600 T/A resulted in soil conditions that
were unfavorable to late-season growth of the 1970 corn
crop. The moderately stunted and yellow plants that
developed on plots receiving even the minimum amendment of
200 T/A were rated with a Total Quality Score (TQS) of 12
compared with the TQS of 18 given seedlings on comparable
control plots. However, plots fertilized with nitrogen
at a 100:1 carbon-nitrogen ratio as shown in Table 25
produced corn stands with TQS of 18 that were comparable
to controls.
Corn yields in 1970 from plots amended with sludge but not
fertilized with nitrogen were from 14 to 60 percent lower
than yields from the untreated (no nitrogen fertilization)
control plots. Nitrogen additions at C:N of 100:1 increased
the corn production of all sludge amended plots with the
highest yield in 1970 harvested from the 200 T/A plots
supplemented with nitrogen at the C:N of 100:1. Yield of
55.5 Ibs from corn grown on untreated control plots was
approximately 20 percent less than the nearly 70 Ibs
obtained from the 200 T/A sludge-nitrogen plots. Yields
from control plots were reduced by all of the tested
levels of nitrogen fertilization.
Soil conditions in plots at all levels of sludge without
nitrogen supplement were highly unsatisfactory for growth
of the bean test crop in 1970. Low TQS of 10, 9> and 8
were obtained at rates of 200, 400 and 600 T/A. Nitrogen
fertilization equivalent to the C:N of 100:1 offset some
of the adverse growth conditions, but even at the optimum
sludge-nitrogen C:N of 100:1, bean growth on the 200 T/A
plots was rated li compared with the 17 for non-nitrogen
fertilized control plots.
Bean yields in 1970 of practical significance were obtained
only from crops grown on the 200 T/A sludge amended plots.
The phytotoxic properties of sludge even at the low 200
T/A rate resulted in an approximate 1/3 lower yield than
that obtained from comparable controls. Nitrogen additions
to amended plots at apparent optimum C:N of 100:1 did not
return yield to the level obtained from the unarnended, and
non-nitrogen fertilized plots.
71
-------
Plot Quality Evaluation--1971
Growth and development of corn test plants on all plots
amended with sludge only and sludge-nitrogen combinations
was superior to that on control plots as shown by TQS.
The unfavorable soil conditions associated with the 400
and 600 T/A amendments observed in the 1970 corn crop were
totally absent in the 1971 corn crop and TQS of 19 resulted
even at the excessive nitrogen level based on the C:N of
10:1. In addition the TQS of corn at the 200 T/A amendment
was lower than those at the 400 and 600 T/A in the 1971
crop, just the reverse of the TQS of corn observed in
1970. These latter data suggest that peak productivity
of the 200 T/A amended plots was in 1970 and the 400 and
600 T/A plots respectively have reached or are approaching
their stage of maximum production.
The corn yields in 1971 paralleled the TQS with production
from all sludge amended plots greater than those of
controls. Maximum harvests were obtained from the 400 T/A
sludge addition fertilized at the C:N of 50:1 and 100:1.
Yields lend support to the concept that peak production is
related to both the rate of sludge amendment as well as
the elapsed time between incorporation and plot use for
crop culture.
TQS observations were not made for the 1971 bean test
crop. Bean yields in 1971 from the three sludge amendment
rates alone and in combination with nitrogen at C:N of
50:1 and 100:1 were all greater than those from control
plots. The shift in peak yield production from low to
high sludge amendment with successive (years) corn crops
is not nearly so discernible with the bean test crop.
The relationship does occur however with peak yields at
200 T/A in 1970 and at 600 T/A in 1972.
Plot Quality Evaluation--1972
In the third year following the single sludge application
to field plots, growth of the corn test crop was most
favored by the 600 T/A amendment. Near optimum and
essentially identical growth responses 1 month before
harvest resulted in TQS of 20 for all conditions relative
to nitrogen supplements. In contrast, control or unamended
plots produced corn rated 7 and 16 in the case of the
high and no nitrogen supplemented plots, respectively.
72
-------
Corn yields from the 1972 crops were greatest with the
600 T/A sludge amendment and were not influenced by
nitrogen fertilization. As shown in Table 23 no statistical
differences were noted in yields from corn grown on
nitrogen supplemented subplots and comparable controls.
Statistical data in Table 24 also show that growth of
beans in 1972, as with corn, was favored by the 600 T/A
amendment. The highest TQS were obtained with nitrogen
additions at the C:N of 50:1 and 100:1 and with no
nitrogen supplement.
The 1972 bean yields from sludge amended plots exceeded
those from controls. High, but non-significantly,
different yields were produced both with nitrogen supple-
ments at C:N of 50:1 and 100:1 and without the nitrogen
additive. Those data shown in Table 25 indicate nitrogen-
added at the time of sludge incorporation, which was
necessary for the first and second crop years, was not
required for high yields in the third year.
The quality of land used in the present study is shown by
the corn and bean yields obtained from the unamended
control plots. The summary Table 25 shows bean yields
from non-nitrogen control plots in 1970 of 32.2 Ibs
decreased to a level of only 17 Ibs or so in the two
following years and corn production of 55-5 Iks in 1970
decreased to 26.3 Iks in 1971 and 28.3 Ibs in 1972.
Supplemental nitrogen alone was not sufficient to offset
this yield reduction for either crop.
During the initial or 1970 bean crop harvest, observations
indicated a more rapid development of pods to the fresh
or processing market stage on the sludge amended plots.
Harvests in the following two years were made at one week
intervals as pods reached the stage suitable for table
use. Peak yields were obtained in the second picking from
plots amended with 600 T/A, compared with the even distri-
bution of control yields over the 2 and 3 harvest dates.
As shown in Table 26 with the 1972 crop, all 400 T/A plots,
except the sludge-nitrogen combination at the 10:1 C:N,
and all 600 T/A plots produced peak yields of fresh market
quality beans one week earlier than did the untreated or
nitrogen amended control plots.
73
-------
TABLE 26
EFFECT OF SLUDGE ON BEAN MATURITY RATE WHEN GROWN ON TOLERANCE PLOTS
6A
6B
6c
6D
7A
7B
7C
7D
8A
8C
8D
Sludge
Tons/A
0
0
0
0
200
200
200
200
400
400
400
400
600
600
600
600
Nitrogen
Addition
Lbs-N
91.6
18.3
9.2
0
C:N
10:1
50:1
100:1
0
Picking Dates—1971
Picking Dates—1972
10:
50:
100:
0
10:
50:
100
0
9/2
Lbs
0
0.2
1.2
1.5
0
1.5
2.8
2.8
0.1
2.1
3 0
2.8
0.3
2.7
2.4
1.7
9/9
Lbs
0.1
lf-5
4.7
18.2
0
6.2
8.4
IB. 5
0.2
9.5
11.3
8.2
0.4
15.0
l4.6
11.1
9/19
Lbs
0.2
2.8
17-2
7.8
0
10.7
12.3
9.9
1.6
7.8
12.4
9.1
i-2
6.6
10.3
7.3
Yield
Lbs
0.3
4.6
13.1
17.4
0
18.4
23.4
21.2
1.8
^•S
26.8
20.7
2.6
24.4
27.4
20.1
Lbs
0
1.1
6.2
6.3
0
9.8
9.7
10.6
9-2
12.6
ll.b
9.9
10.5
14.7
15.5
12.8
9/14 .
Lbs
0.
3.
9.
5.
0.
9.
9.
9.
HoT
9.
8.
8.
8.
8.
11.
10.
l
5
1
3
1
?l
4
°l
1
l
4
8
4
1
1
9/24
Lbs
0
1.6
4.3
3.9
0.1
0.9
8.1
8.1
6.7
7.6
7.6
5.1
8.4
12.4
12.5
11.1
9/2b
Lbs
0.1
2.6
2.7
2.4
0.7
2.7
1 4.1
3.9
3.5
4.2
3.5
2.9
3^6
4.5
Yield
Lbs
0.4
8.8
22.2
17.9
0.8
28.5
31.2
31.5
30.2
33.7
30.7
27.9
30.5
39.1
42.7
38.5
Data included in each blocked area across the page are not significantly different from
each other but are significantly different from values outside blocked area.
-------
YEARLY AMENDMENT DESIGN
Plot Quality Evaluation—1970
Detailed data concerning total quality scores and yields
are shown in Tables VI, IX and X in the Appendix for the
Yearly Amendment Design portion of this study. For
convenience summaries of these data are given in Tables
27, 28 and 29 in the text.
Results and discussion concerning the Yearly Amendments of
200 and 400 T/A are contained in the Tolerance portion of
the report since during the first crop year at these common
rates of amendment, no difference existed in the two
disposal approaches.
The 1970 corn stands on plots amended with sludge at 100
T/A were equivalent to or slightly better than those of
controls with TQS of 19 and lb respectively. These low
levels of amendment were not phytotoxic and did not cause
a nitrogen deficiency in test plants. Yield was not
altered by the 100 T/A sludge addition, and tilth and
color of soil were noticeably improved over those of
controls.
As shown in Table 29 Total Quality Scores of 20 for bean
crop on the 100 T/A amended plots compared with the 17 for
controls reflects the near ideal soil conditions resulting
from the organic amendment. Data in Table 28, however
show that only a slight yield increase in the 100 T/A
amendment occurred and is not statistically different from
yield obtained from the control (no sludge-no nitrogen).
Plot Quality Evaluation--1971
Soil conditions of Yearly Amendment plots were markedly
altered by the second sludge amendment and at the 200 and
400 T/A rates resulted in delayed or pre-emergence seedling
death, light green leaves indicating nitrogen deficiency,
and marked stunting of the corn test crop. Successive
annual additions of the 100 T/A amendment in combination
with nitrogen at C:N of 50:1 in contrast produced favorable
soil conditions and corn stands superior to those of control
plots as shown by the TQS of 19 compared with 18 for
controls.
75
-------
TABLE 27
STATISTICAL RANKING ACCORDING TO DUNCAN'S NEW MULTIPLE RANGE TEST FOR CORN YIELD,
YEARLY AMENDMENT DESIGN FOR 1970, 1971, 1972
1970 1971 1972
Plot Sludge Nitrogen Yield Plot Sludge Nitrogen Yield Plot Sludge Nitrogen Yield
No. Tons/A Addition Lbs No. Tons/A Addition Lbs No. Tons/A Addition Lbs
12A 400 10:1 (
9A 0 45. 8# 3,<
11A 200 10:1 4.C
10A 100 10:1 10.'
12D 400 0 27.6
12B 400 50:1 28. <
9B 0 9-2# 29.?
11B 200 50:1 39.-
12C 400 100:1 42. (
9C 0 4.6# 42. £
11C 200 100:1 47. £
10B 100 50:1 49.:
9D 0 0 51.!
IOC 100 100:1 52 J
11D 200 0 54..
10D 100 0 55.!
STATISTICAL
) 9A 0 18. 3# 0
) 10D 100 0 0.2
) 11C 200 200:1 0.5
j 11D 200 0 0.5
j 12D 400 0 1.2
) 12C 400 200:1 3.6
) 12B 400 100:1 3-7
} 12A 400 50:1 5.8
) 11B 200 100:1 6.0
3 11A 200 50:1 6.4
> IOC 100 100:1 13.4
L IDA 100 50:1 31.6
3 9D 0 0 32.8
4- 9C 0 4.5# 40.3
L 10B 100 100:1 40.5
3 9B 0 9.2# 47.2
TABLE 28
9A 0 18. 3# 0
11D 200 0 2.6
11C 200 200:1 3.1
11B 200 100:1 4.3
11A 200 50:1 6.1
9B 0 9.2# 6.9
10D 100 0 21.4
IOC 100 200:1 27.5
12D* — — 27.8
12B* — — 28.3
9D 0 0 30.8
9C 0 4.5# 32.0
12A* — — 32.9
12C* ~ « 35.3
10A 100 50:1 37.8
10B 100 100:1 39.8
RANKING ACCORDING TO DUNCAN'S NEW MULTIPLE RANGE TEST FOR BEAN YIELDS,
YEARLY AMENDMENT DESIGN FOR 1970, 1971, 1972
1970 1971 1972
Plot Sludge Nitrogen Yield Plot Sludge Nitrogen Yield Plot Sludge Nitrogen Yield
No. Tons/A Addition Lbs No. Tons/A Addition Lbs No. Tons/A Addition Lbs
15A 200 10:1 0
16A 400 10:1 0
13A 0 45. 8# 0.1
14A 100 10:1 0.2
16B 400 50:1 1.6
16C 400 100:1 4.8
16D 400 0 6.0
15B 200 50:1 10.4
13B 0 9.2# 17.9
14B 100 50:1 27.3
13C 0 4.6# 33.2
15D 200 0 34.3
15C 200 100:1 36.0
13D 0 O 37.2
14D 100 0 40.3
14C 100 100:1 41.4
13A 0 18. 3# 0
16D 400 0 0
15A 200 50:1 0.3
14A 100 50:1 0.9
16C 400 200:1 0.9
16B 400 100:1 1.5
15D 200 0 2.1
16A 400 50:1 3.8
14D 100 0 6.7
15B 200 100:1 7.5
13B 0 9.2# 7.9
15C 200 200:1 8.1
14C 100 200:1 15.9
14B 10O 100:1 19.0
13D 0 0 22.6
13C 0 4.6# 24.5
13A 0 18. 3#
15A 200 50:1 0.
15C 200 200:1 1.
15 B 200 100:1 1.
15D 200 0 1.
14A 100 50:1 2.
13B 0 9.2# 4.
16D* — — 4.
14D 100 0 5,
16B* — — 6
l6c* — ~ 6
13C 0 4.6# 9
16 A* — — 16
14C 100 200:1 18
14B 100 100:1 19
13D 0 0 27
0
6
2
I
1
5
7
3
1
7
2
0
7
J
*400 T/A addition third year was not possible — yield values not comparable.
Any two values not bracketed by same line are significantly different; any two values bracketed are not significantly
different at 5# level.
-------
TABLE 29
Sludge
T/A
0
0
0
0
100
1OO
1OO
100
200
20O
200
200
400
400
400
400
Nitrogen
Addition
Ibs
45.8
9.2
4.6
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
SUMMARY— YEARLY AMENDMENT
DESIGN
Total Quality Score
1970
0
14
15
18
7
16
19
19
2
16
18
12
0
12
16
9
Corn
1971
14
18
15
16
17
19
17
12
13
14
14
4
10
13
13
3
1972
0
9
13
15
14
10
7
8
6
4
3
2
12
14
13
10
Beans
1970 1971
0 — *
9
11
17
6
13
16
20
6
12
14
10
0
10
12
9
1972
0
6
10
10
7
14
12
/ 6
5
6
6
6
11
8
8
8
1970
3-0
29.9
42.8
51.8
10.3
49.1
52.4
55.8
0
39-3
47.5
54.1
0
28.0
42.0
27.6
Yield, Ibs /subplot
Corn
1971
0
47.2
40.3
32.8
31.6
40.5
13.4
0
0
6.0
0.5
0.5
0
3.7
3.6
1.2
1972
0
6.9
32.0
30.8
37.8
39.8
27.5
21.4
0
4.3
3.1
2.6
0
28.3
35.3
27.8
1970
0.1
17.9
33.2
37.2
0.2
27.3
41.4
40.3
0
10.4
36.0
34.3
0
1.6
4.8
6.0
Beans
1971
0
7.9
24.5
22.6
O.Q
19.0
15.9
6.7
0
7.5
8.1
2.1
0
1.5
0.9
0
1972
0
4.5
9.2
27.4
2.1
19-3
18.7
5.3
0
1.7
1.2
1.8
0
6.1
6.7
4.7
*Total quality scores not observed in 1971.
-------
The level of optimum sludge amendment relative to corn
yield was as earlier indicated by the TQS 100 T/A in
combination with nitrogen at C:N of 50:1. On the basis of
two crop seasons, yearly amendments of no more than 100
T/A in combination with nitrogen would permit more or less
continuous and concurrent use of farm land for sludge
disposal and crop production.
Quality Test Scores of beans were not determined for the
1971 Yearly Amendment Design because of the marked sensi-
tivity of beans to the first of the three amendments.
Bean yields in 1971 following the second addition of sludge
at 100 T/A were from 60 to 80 percent less than yields
from these plots in 1970. Bean yields from incorporation
of sludge under the Tolerance design at 200 T/A as a single
amendment without nitrogen in the fall of 1969 were essen-
tially identical in 1970 and 1971. Split application of
sludge at the 200 T/A rate, with half portions applied in
1969 and 1970, however, resulted in a many-fold reduction
in the 1971 yield.
The toxic factors of sludge are more apparent and yield
reductions of corn and beans are greater when sludge
incorporation into soil is by Yearly Amendment than by
Tolerance design.
Plot Quality Evaluation—1972
Total quality scores of corn in 1972 plot evaluation were
lower than those of controls at both the 100 and 200 T/A
amendment levels with the exception of the sludge-nitrogen
combination of 100 T/A—10:1 C:N. No consideration
relative to original experimental design should be given
the 400 T/A amendment of the Yearly Amendment approach
as the third aliquot of sludge could not physically be
worked into test plots.
Corn yields resulting from yearly amendments of 100 T/A
at C:N of 10:1 increased over 3 years from 10.3 to 37.8
Ibs per subplot. At the same sludge level but with lower
nitrogen fertilization level of 50:1 C:N, yield was evenly
distributed over a 3 year period. Extreme reductions in
yield resulted from yearly amendments of 200 T/A however.
The third successive amendment at the 400 T/A rate could
-------
not be physically incorporated into plots and as a conse-
quence was eliminated from study. In view of the reduced
yield in the 1972 crop on the 400 T/A plots, it appears
reasonable to assume adverse effects equal to or greater
than those obtained with the third incorporation of 200 T/A,
The 100 T/A sludge amendment applied to soil with nitrogen
at C:N of 50:1 and 100:1 for 3 successive years produced
bean plants of better quality than those of controls.
The TQS obtained for plants on sludge amended plots of 14
and 12 for the low and high C:N respectively and those of
6 and 10 for comparable controls show the moderately
superior condition of beans on the sludge amended plots.
No major differences in yields were observed between the
1971 and 1972 bean crops grown at all nitrogen levels on
the 100 T/A Yearly Amendment plots. The maximum yield in
1972 from the 100 T/A plots however was 40 percent less
than that from the control plots. Reductions in yield
of up to 90 percent or so resulted from successive yearly
incorporation of 200 T/A rates.
DISPOSAL DESIGN
Plot Quality Evaluation—1972
Growth of corn and beans on the Disposal plots paralleled
that of the test crops on the Yearly Amendment plots.
The TQS shown in Table 30 indicates that optimum growth
under both objectives occurred at the 100 T/A level with
the nitrogen addition most favorable in the Disposal
approach at C:N ranging from 50:1 to 100:1 and in Yearly
Amendment, from 10:1 to 50:1.
Corn yields as depicted in Tables 31 and 32 were signifi-
cantly greater with 100 T/A amendments from the Yearly
Amendment than from the Disposal plots. In contrast, no
differences occurred in bean production from 100 T/A plots
amended under the two objectives, but yields were well
under those from control plots.
79
-------
TABLE 30
TOTAL QUALITY SCORES OF 1972 CORN AND BEAN
CROPS ON DISPOSAL DESIGN PLOTS
Sludge
T/A
0
0
0
0
100
100
100
100
200
200
200
200
400
400
400
400
Nitrogen
Addition
Ibs
45.8
9.2
4.6
0
C:N Ratio
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Total
Plot
No.
1?A
17B
17 C
17D
18A
18B
18 C
18D
19A
19B
19C
19D
20A
2 OB
20C
20D
Quality Scores
Corn
0
8
12
17
8
11
6
5
4
6
6
6
12
11
12
7
Plot
No.
21A
21B
21C
2 ID
22A
22B
22 C
22D
23A
23B
23C
23D
24A
24B
24C
24D
Beans
1
4
10
15
4
7
10
6
5
6
6
7
9
7
8
6
80
-------
TABLE 31
EFFECT OF CLARIFIER SLUDGE ON CORN AND BEAN YIELD
IN FIELD PLOT DISPOSAL STUDIES
Sludge
Tons/A
0
0
0
0
100
100
100
100
200
200
200
200
400
400
400
400
Nitrogen
Addition
Lbs-N
45.8
?'£
4.6
0
C;N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Plot
No.
17A
1?B
17 C
17D
18A
18B
18C
18D
19A
19B
190
19D
20A
2 OB
20C
20D
Lbs
Corn
1.0
5.0
21.0
40.7
20.7
26.7
21.6
10.8
22.8
6.2
6.2
7.3
26.5
20.9
12.5
14.3
Plot
No.
21A
21B
21C
2 ID
22A
22B
22C
22D
23A
23B
23C
23D
24A
24B
24C
24D
Lbs
Beans
0
1.5
5.3
23.2
1.6
10.4
19.2
5.8
0.8
1.7
5.7
0.9
7.3
3.3
3.5
4.6
81
-------
CO
CO
TABLE 32
STATISTICAL RANKING ACCORDING TO DUNCAN'S NEW MULTIPLE RANGE TEST FOR
CORN AND BEAN YIELD--DISPOSAL DESIGN FOR 1970, 1971, 1972
Plot
No.
17A
17B
19B
19C
19D
18D
20C
20D
18A
20B
17 C
18C
19A
20A
18B
17D
Sludge
Tons /A
0
0
200
200
200
100
400
400
100
400
0
100
200
4 00
100
0
Nitrogen
Addition
45.8$
9.2#
50:1
100:1
0
0
100:1
0
10:1
50:1
4.6#
100:1
10:1
10:1
50:1
0
Corn Yield Plot
Lbs No.
1.0 21A
5.0 23A
6.2 23D
6.2 21B
7.3 22A
10.8 23B
12 . 5 24B
14. 3 24c
20.7 24D
20.9 21C
21.0 23C
21.6 22D
22 . 8 24A
26.5 22B
26.7 22C
40.7 21D
Sludge
Tons /A
0
200
200
0
100
200
400
400
4oo
0
200
100
400
100
100
0
Nitrogen
Addition
45.8
10:1
0
9.2
10:1
50:1
50:1
100:1
0
4.6
100:1
0
10:1
50:1
100:1
0
Bean Yield
Lbs
0.0
0.8
0.9
1.5
1.6
1.7
3-3
3.5
4.6
5.3
5.7
5.8
7.3
10.4
19.2
23.2
Any two values not bracketed by same line are significantly different; any two
values bracketed are not significantly different at 5$ level.
-------
CHARACTERISTICS OF SLUDGE AMENDED SOILS
The initial incorporation of sludge into field plots at
the 100, 200 and 400 T/A rates produced an immediate
improvement in soil tilth. The 600 T/A amendment however
was so voluminous that even with batch wise rotovation of
the total amount in 3 or 4 separate portions the top 6
inches or so of the plot was not satisfactorily mixed with
the deeper portions. Improved tilth at all amendment
rates, including the 600 T/A was noted during the 1970
spring plot rotovation and preparation for seeding.
Large pancake-like fungal growths occurred on the surface
of sludge amended plots from early spring in 1970 and 1971
through both crop seasons. Observations in April and
August of 1972 as shown in Table-33 established a positive
correlation between the presence of fungi and the yearly
addition of sludge.
Sludge incorporation in the fall of 1970 and 1971 to
Yearly Amendment and Disposal plots became increasingly
more difficult with each amendment. Formation of sludge-
clay aggregates of fist size and larger throughout plots
produced isolated islands of sludge in various stages of
decomposition. Incomplete mixing of the third sludge
addition with soil and partially composted amendment of
previous years was wide-spread during the third and final
year of sludge addition.
Following crop harvest in 1972, soil samples were obtained
from all plots for ash and volatile solids analysis.
Sample cores collected from five random areas within each
sub-plot were combined, mixed and a 500 g portion air
dried and stored for later analysis.
Volatile solids levels as shown in Table 34 in the fall
of 1972 of all soils amended with sludge between 1969 and
1972 were greater than those of unamended control soils.
The increase in volatile or organic components of soil
was proportional to the quantity and frequency of sludge
addition. A total of 600 T/A applied in yearly amendments
of 200 T/A increased residual organic content in 1972 by
190 to 220 percent, while application in 1969 of the entire
600 T/A in the Tolerance design increased the organic
fraction in 1972 by only 80 to 90 percent. Undegraded and
83
-------
TABLE 33
EFFECT OF 8 AND 30 MONTHS RESIDENCE OF SLUDGE
AMENDMENTS ON OCCURRENCE OF SURFACE FUNGAL GROWTHS
Disposal
Design
Yearly
Amendment
8 Mo. Residence
Disposal
8 Mo. Residence
Tolerance
30 Mo. Residence
Controls
Sludge
T/A
100
200
400
100
200
400
200
400
600
None
Nitrogen
C:N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
All Levels
All Levels
All Levels
All Levels
84
Fungal Growths
(Avg. No./
Replicate )
12
11
12
12
12
11
9
3
6
13
9
9
9
8
16
12
11
13
15
5
7
12
8
10
None
None
None
None
-------
TABLE 34
ASH AND VOLATILE SOLIDS CONTENT OF SLUDGE AMENDED SOILS
CO
VJ1
Sludge
T/A
0
0
0
0
100
100
100
100
200
200
200
200
200
200
200
200
400
400
400
400
600
600
600
600
Percent
Disposal
Design
Control
Control
Control
Control
Y.A.*
Y.A.
Y.A.
Y.A.
Y.A.
Y.A.
Y.A.
Y.A.
T*
T
T
T
T
T
T
T
T
T
T
T
Nitrogen
Ibs
91.6
18.3
9.2
0
C:N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Plot
No.
1A
IB
1C
ID
10A
10B
IOC
10D
11A
11B
11C
11D
2A
2B
2C
2D
3A
3B
3C
3D
4A
4B
4c
4D
Ash
90
90
90
90
84
81
82
85
68
68
69
71
87
87
87
87
85
84
35
85
81
81
81
82
Volatile
Solids
10
10
10
10
16
1Q
JLo
15
32
32
31
29
13
13
13
13
15
16
15
15
19
19
19
18
Increase In
Volatile Solids,
Percent
60
90
80
50
220
220
210
190
30
30
30
30
50
60
50
50
90
90
90
80
*Y.A. - Yearly Amendment; T - Tolerance Design.
-------
partially degraded components of the 3 yearly amendments
of 200 T/A are the dominant factors in the accounting for
the 6-8 inch greater elevation of the Yearly Amendment over
the 600 T/A Tolerance plots. The photograph in Figure 15
shows the difference in plot volume when sludge was added
at a rate of 200 T/A each of 3 years or 600 T/A in the
first year.
Corn crops within 2-3 weeks of harvest on the 400 and 600
T/A Tolerance plots were free from symptoms of water
stress during a 2 week hot spell in late August 1972,
while the corn on all other amended and unamended plots
showed marked wilting from water deficiency. As shown in
Figure 16 the temporary wilting was most evident immediately
prior to irrigation. Frequency of irrigation minimized
adverse effects of water stress on yield, but under general
field conditions amendments such as sludge that prevent
such stress could be of agricultural importance.
86
-------
*A
Plot on left received 600 T/A in Fall of 1969.
Plot on right received 200 T/A/yr for 3 years.
FIGURE 15. COMPARISON OF TWO PLOTS RECEIVING TOTAL OF
600T/A SLUDGE.
87
-------
A.
i inn
0" Tons/Acre Sludge
'
No Nitrogen
9.2# Nitrogen
Closeup of Left Subplot in "A"
B.
400 Tons/Ac re Sludge
No Nitrogen
9.2# Nitrogen
Closeup of Left Subplot in "B"
FIGURE 16. EFFECT OF SLUDGE ADDITION ON WILTING OF CORN.
-------
SECTION XI
MULCHING
ROAD CUT HYDROMULCH
Disposal of paper mill sludge as a hydromulch material
offers a substantial volume outlet. The major use is in
formulation of a grass planting slurry which is sprayed on
highway cuts. The mulch provides the medium for holding
seeds until they germinate. It also holds moisture and
fertilizer so that after the application, no further
attention is necessary. The mulch will slowly decompose
adding humus to the soil. *
To simulate a highway-cut embankment^ a 30° angle hillside
slope was levelled and covered with 3-4 inches of top
soil. As shown in Figure 17 the slope was divided into
5 plots each 5 ft wide by 14 ft long. Type of equipment
used and method of application are also shown. Amounts of
grass seed and fertilizer used for each of the 3 plantings
are shown in Table 35.
TABLE 35
APPLICATIONS ON HYDROMULCH PLOTS
Application Date 4/13/71 9/24/71 4/26/72
Lb Grass Seed/Acre* 260 390 390
Type Fertilizer, %
(N-P-K) 5-10-50 23-19-17 23-19-17
Lb Fertilizer/Acre 1270 415 415
^Highway grass seed mix of 50$ English rye and 50$ creeping
fesque.
89
-------
5' x 14' Hydromulch Plots
Application of Hydromulch
Hydromulch Mix
Tank, Mixer, Pump
FIGURE 17, HYDROMULCH APPLICATION ON SIMULATED
HIGHWAY ROAD CUT.
90
-------
Each grass seed-fertilizer combination which was slurried
for hydromulching was mixed in a 100 gallon feed tank.
Slurrying was accomplished with an air motor-driven portable
mixer. Slurries were pumped from the tank by a gasoline-
driven portable pump and sprayed on each plot.
Giving each application a weighted rating, i.e., its
average, it appears that almost any formulation except
3000 and 6000 Ib/acre of sludge would equal or excel the
wood fiber product. From Table 36, this would include
mixtures rated 3 or lower. The choice of hydromulch
product then depends on comparative prices of the material.
The cost without profit of a delivered bale of semi-dried
sludge in a local area is about $20/dry ton. Pressed
sludge, delivered in bulk, would be $14-17/dry ton. With
a reasonable addition of profit and selling cost to the
above, the product should be competitive to materials now
being used.
Because the basic operation of hydromulching is spraying
on material as a slurry, an important objective is to
apply at high solids content, or consistency. Generally,
paper mill sludges have a low enough freeness, or drainage
rate, to stay well mixed in water. The data of Table 36
show that in all cases, sludge and sludge-bark mixtures
can be applied at higher consistencies than the wood fiber
hydromulch.
Variable amounts of sludge and sludge-bark mixtures were
compared to a control wood fiber hydromulch. Plots were
not watered during the growing period of 60 to 90 days.
At the end of the growth period each plot was visually
rated for growth and coverage.
Differences can be noted in the photographs shown in
Figure 18 taken of one planting series; however the
final evaluations were based on overall plot growth.
These ratings for each series are'shown in Table 36.
-------
TABLE 36
HYDRQMULCH APPLICATION AND EFFICACY RATING
Plot Lb Wood Lb Sludge Lb Bark Application
Rating Fiber/Acre /Acre Dust/Acre Consistency, ?
4/13/71
1 — 1000 + 1000 1.96
2 2000 — — l-4l
3 -- 2000 — 1.96
4 — 1500 + 1500 2.27
5 — 3000 — 2.27
9/24/71
1 — 4000 — 2.90
2 — 2000 + 2000 2.90
3 — 1500 + 1500 2.15
4 — 3000 — 2.50
5 2000 — — 1.10
4/26/72
1 -- 3000 + 3000 3.04
2 — 4000 — 2.44
3 2000 — ~ 0.98
4 — 6000 — 2.41
* — 2000 + 2000 2.44
92
-------
xS
50% SLUDGE-50%
<
2000#lAcRE
.
1
WOOD-FIBER HYDROMULCH^ 2000#lAcRE
100% SLUDGE, 2000#1A:RE
50? SiUDGE-50% BARK, 3000#1A:RE
100% SLUDGE, 3000#JA:RE
FIGURE IS, GRASS GRO^fTH-HYDROMULCH PLOTS V13/7L
93
-------
CROP MULCHING
Hydromulching
Evaluation of mulching potential of sludge was made with
raspberry, strawberry, and tomato test crops grown in
10 x 38 ft plots. Plot design is shown in Figure 19.
Four plots of a single row of Willamette variety of red
raspberry transplants were established with 4 foot spacing
between plants. Four plots of Northwest variety strawberry
plants were set in 3 rows per plot with spacing of 3^ feet
between rows and l£ feet between plants. The Earlianne
tomato test crop was not planted until after sludge
application. Three plots of tomatoes on 3^ foot centers
were set into soil by removing an approximate 4 inch
diameter disc of the sludge blanket for each transplant.
Sludge was applied as a slurry or hydromulch for the
hydromulch study. In order to facilitate application, an
approximate 1.3^ slurry of sludge was maintained in
suspension by constant stirring and sprayed on surface of
plots through a specially designed nozzle. Plants
established in plots prior to hydromulching were covered
to keep foliage free of sludge.
One of the four prepared plots of raspberry was used in a
special treatment not related to mulching study. This
single plot was amended with sludge at a 200 T/A rate and
nitrogen to give a C:N ratio of 100:1 prior to planting
of test plants.
Effectiveness of the sludge hydromulch in weed control
was measured by weight of weeds harvested and time interval
required to remove weeds. Both weed yield and removal
intervals decreased with increased thickness of mulch.
The hydromulch layer was ineffective in control of such
weed species as Canadian thistle and Quack grass.
Tomato Yield
Tomatoes were picked through the growing season as they
ripened. Final harvest was made the day following the
first killing frost. Total number and weight of harvested
fruit along with percentage by weight and number exhibiting
soft spots are given in Table 37-
-------
10'
Mulch Layer
- Tom™ 0 — — 1 Lbs/sq ft Tons/Acre
: i i i i i i I i i i\ o o
Tomato
nnnnni 0.55 11.9?
Tomato
Ull III llll 0.76 16.55
Mushroom
Nitrogen I Nitrogen I Sludge Incorporation 200 T/A
Raspberry
* * • ..... • • • Sludge Incorporation 200 T/A
Raspberry
........... 0. 37 8. 09
Kaspperrv
........... 0.51 11.11
Raspberry
0 0
Strawberry
• •••••••••••••••••••
••*•••••••••••••••••
Strawberry
• •••••••••••••••••••
• •»•••••••••••••••••
Strawberry
• •••••••••••••••••••
• •••••••••••••••••••
n
U.
n
U.
n
U.
o /ic
0.4!?
n
11.
strawberry
••••••••••••••••••••
••••••••••••••••••••
n
U
38
FIGURE 19. DESIGN SHOWING HYDROMULCH PLOTS.
95
-------
TABLE 37
EFFECT OF HYDROMULCH ON TOMATO YIELD
Hydromulch Percentage
Addition Total Total Soft Tomatoes,
Tons/ALbs/sq fT Lbs/Plot Number/Plot By WtBy NoT
Control—No Mulch 343 1226 8.4 7.8
12 0.55 250 773 3.9 4.1
17 0.76 247 786 2.7 3.6
Tomatoes transplanted through a mulch layer equivalent to
12 and 17 tons/acre resulted in poor growth and reduced
yields. Light green color of foliage developed early in
season with plants grown on mulched plots, indicating an
adverse effect. Sludge layer did however provide a barrier
between fruit and soil. Fruit resting on soil had a higher
incidence of "soft spot" than tomatoes resting on the
hydromulch sheet.
Raspberry and Strawberry Yields
In 1970 excessive weeds plagued control plots. Their
removal disturbed strawberry plant growth which subsequently
resulted in 1971 yield decrease. There were considerably
less weeds on treated plots and their removal had less
impact on plant growth.
Results shown in Table 38 show a very low strawberry yield
in control plot compared with yields normally obtained in
that area. Data do indicate, however, that hydromulching,
even though effective in weed control, decreased strawberry
yield. When hydromulch layer was increased in thickness
from 5.3 to 11.8 T/A, yields decreased from 171.3 to 87.9
Ibs. These data are similar to those in the raspberry
plots. Photographs in Figure 20 depict hydromulch appearance
and its effect on strawberry, raspberry and tomato plants.
-------
,.,. .,
, -
«*•
Strawberry •• Control
Raspberry - Control
Tomato - Control
0.54lbs/sqft
^^^^^^^H^|^^M|UB^^^g^ ,
I
0.51 Ibs/saft
0.76lbs/sqft
FIGURE 2Q EFFECT OF HYDROMULCH LAYER ON TEST CROPS.
97
-------
TABLE 38
RASPBERRY AND STRAWBERRY YIELDS ON
HYDROMULCHED PLOTS
Crop
Strawberry
Strawberry
Strawberry
Strawberry
Raspberry
Raspberry
Raspberry
Sludge
Tons/Acre
0
5.3
8.5
11.8
0
8.1
11.1
Addition
Lbs/sq ft
0
0.24
0.39
0.50
0
0.37
0.51
Pounds — Total Yield
45.8
171.3
99.1
87.9
38.6
12.5
25.6
Bulk Mulching
After 1970 and 1971 harvest data were collected, the
strawberry and raspberry plants were thinned to uniformity.
The revised experimental scheme, shown in Figure 21 was
designed to obtain greater replication, evaluate mulching
rather than hydromulching and to determine effect of varying
sludge depth.
After 1971 harvest each plot was divided into 10' x 10'
subplots leaving 4 feet of guard plants on each end.
Subplots were divided with 2" x 10" planks. Raspberry
plants grown on sludge incorporated plots were also used
in the design.
Sludge having a wet density of 42.3 Ibs/cu ft or 10.6 Ibs/
cu ft (dry basis) was placed in the enclosures to measured
depths varying from 1.5 to 6 inches.
98
-------
•
-
D A C
•
•
B D C
•
•
C B A
•
•
BAD
*
iniii
llllll
imii
i
D A, C
9
imii
mm
mm
i
B D C
*
******
••••••
••••••
mm
•
C B A
•
••• •••
••••••
•• ••• •
• • ••• •
•• ••• •
•••• • •
i
BAD
Raspberry Plots
Mulch Layer
Thickness Tons
Subplot (Inches) Per Acre
A 0 0
B 2 38. 4
C 4 76. 8
D 6 115.2
Strawberry Plots
Mulch Layer
Thickness Tons
Subplot (Inches) Per Acre
AGO
B 1. 5 28. 7
C 3. 0 57. 4
D 5. 0 95. 9
FIGURE 21. RANDOMIZED PLOT DESIGN FOR
BULK MULCH ING EXPERIMENT.
99
-------
Analysis of data summarized in Table 39 and shown in more
detail in Tables XI and XII, in Appendix, indicate a
significant difference in yields obtained with treatments
on strawberry plots. However no significance could be
obtained with sludge addition on raspberry plots.
TABLE 39
SUMMARY OF STRAWBERRY AND RASPBERRY YIELD DATA
UNDER BULK MULCH CONDITIONS
Crop
Sludge
Tons/Acre
rry 0
rry 28.7
rry 57.4
rry 95.9
ry 0
ry 38.4
ry 76.8
ry 115.2
Addition
Tnches Thick
0
1.5
3.0
5.0
0
2.0
4.0
6.0
Total Ounces Per 3
Plots (10' x 10' )
1761
1689
1434
1203
555
564
728
839
*
Raspberry
Raspberry
Raspberry
Raspberry
*Any two values bracketed by same line are not significantly
different at 5$ level.
Pictures in Figures 22 and 23 show sludge application in
enclosures and randomization of subplots.
100
-------
FIGURE 22.
STRAWBERRY AND RASPBERRY PLOTS SHOWING ENCLOSURES
AND SLUDGE DEPTHS.
-------
FIGURE 23. STRAWBERRY AND RASPBERRY PLOTS
SHOWING ENCLOSURES AND SLUDGE DEPTHS.
102
-------
SECTION XII
MISCELLANEOUS USES
MUSHROOM CULTURE
Dense mats of mycelia composed of separate brown and white
strands were observed during the spring of 1970 in plots
where sludge was incorporated into soil the previous fall.
Two species of fungi are associated with these colored
mycelia. The brown color characterizes the dominant growth
of the Morchella species or the "morel", and the white
mycelium that of the pedodendron species. These two fungi
are invariably found in mixed mycelial association. Growth
of Morchella sp. appears to be dependent upon association
with Oedodendron (5).
The observed mycelium was very productive of morel sporophores
Sludge amendments favored growth of morels of excellent
quality and large size (Figure 24).
The unexpected and large numbers of morels collected from
sludge amended plots were indicative of a possible key
role for clarifier sludge as a component of a morel culture
medium. Commercial mushroom interests have long sought a
successful morel culture medium. However the physical or
chemical factors required to shift the mycelium to fructi-
fication or morel development have not been found.
To test the effect of sludge amendments on morel production
a special test plot was established. Sludge at 200 T/A
was rototilled into a 10 by 38 foot plot. The sludge
amended plot was inoculated with a heavy suspension of
mycelial fragments and spores prepared from morels collected
earlier. Ammonium nitrate was added to £ of the plot to
give a C:N of 100:1. Reduced light intensity and increased
humidity of plot was produced by constructing a box-like
cover which fitted 20 inches above the bed with sides
extending downward to within 6 inches of the soil surface.
Morels continued to appear during the springs of 1971 and
1972. Production of morel was almost without exception
associated with sludge amended plots. The mushrooms
developing in the grassy walkways between beds were
consistently located on the downhill drainage or runoff
side of sludge supplemented plots. However> no morels
occurred on the special plot with the box cover during
either spring of 1971 or 1972.
103
-------
A. Morels Growing on Sludge
Amended Plot
B. Morel Harvest Showing Size.
FIGURE 24. MOREL MUSHROOMS FOUND GROWING
ON SLUDGE PLOTS.
104
-------
Some limited studies were conducted by Dr. C. Fordyce (5)
of the U. S. Department of Agriculture at Beltsville,
Maryland, who became interested in morel growth on the
experimental plots. His work showed Morchella grew well
with abundant sclerotia formation when ammonium nitrate
and yeast extract were added to sludge. His studies also
indicated differences in utilization of sludge by different
strains of Morchella. Use of sludge as casing medium for
Agaricus campestrls, the mushroom of commerce, was not
satisfactory as A. campestris could not penetrate the
sludge layer. Contamination of sludge under mushroom
house conditions by Trie he-derma and Aspergillus species
was observed by both the USDA and a commercial grower.
OIL ABSORBENCY
Clarifier fibers from two mills were evaluated by automobile
garage operators for possible use as a garage floor absorbent
sweeping compound. These materials absorbed oil well, but
overall performance was rated below the products normally
used such as rice hulls and sawdust. The major objection
to rice hulls as a sweeping compound is the severe dust
problem which exists with this material. Dried sludge,
on the other hand, was judged good from a dust standpoint.
Garages pay 5 to 6 cents per pound for rice hulls and other
sweeping compounds such as vermiculite. Dried, particulated
clarifier fiber would probably cost less than 2 cents per
pound in bags. Added to this would be selling expense and
distribution cost.
This study shows that clarifier sludge would probably have
to be sold at a lower price or be physically improved in
order to compete with established sweeping compounds.
A possible suggested use for paper mill sludge has been as
an oil absorbent for accidental oil spills on water.
Laboratory work in evaluating oil absorbency indicates
that on a dry basis, sludge can absorb about 1.2-1.7.times
its weight. This is equivalent to a usage of one cu ft of
sludge for 6 gallons oil spill. To convert sludge into a
product having oil absorbing capabilities, it must be
oil-treated and dried to facilitate handling and storage.
The oil-treated product should also be baled. The estimated
delivered cost of 1000-1400 Ib bales to a destination of
105
-------
250 raiOfi s is about $40/dry ton solids, allowing for a 3
year cash flow pay-out time. As an example, a 46,000 cu ft
"barge load would absorb 276,000 gallons of oil. This would
be a reasonable amount for dockside leakage at a port
location. Tanker spills at sea are usually much larger,
and it would be impractical to use sludge for clean-up.
Information in Table 40 compares sludge to other products
for oil spills.
From data in Table 40, it can be concluded that on the
basis of cost and storage volume, sludge is not a competi-
tive material for oil spill clean-up.
CATTLE FEED
The following evaluations of sludge for silage and as a
source of feed for ruminants were conducted at Louisiana
State .University (LSU) under the direction of Dr. Louis L.
Rusoff, nutritionist, Department of Dairy Science. Source
of sludge was from a southern mill which produces unbleached
kraft pulp that is converted to various grades of coarse
paper and linerboard. Sludge from primary treatment was
centrifuged to a consistency of about 20$. This material
was used for the studies described. Approximate analysis
of the dry product showed that it contained the following:
Crude Protein 2.0
Crude Fat 1.8
Crude Fiber 66.4
Lignin 12.7
Ash 17.1
Silage Feeding Studies
For the initial silage study additives such as Johnson
grass, cottonseed meal, urea and ground corn were used in
different combinations with the sludge in experimental silos,
The silos were 55-gallon drums filled with compressed
material. The ensiled material was stored in the silos for
a period of 4 months. The combinations of additives and
sludge are shown in Table 4l.
106
-------
TABLE
COMPARISON OF MATERIALS FOR OIL SPILL CLEAN-UP
M
O
-1
Material
Ground Pine Bark (Undried)
Ground Bark (Air Dry)
Sawdust (Air Dry)
Chemical Dispersant
Catalyst Powder
Sludge (Dried, Oiled)
Volume Required,
cu ft/million gal. oil
450, ooo
310, 000
330, 000
2,670
800
167,000
Dock- Side Cost,
^/million gal. oil
33,800
58,100
61,900
95,000
106,000
113,000
-------
TABLE 41
ENSILAGE MIXTURES FOR CATTLE FEED STUDIES
Silo
No.
1
2
3
4
5
6
7
8
Dry
Sludge
50
50
50
50
50
50
50
100
Johnson
Grass
50
^5
45
44
—
—
--
M «
Cottonseed Ground Whole
Meal Urea Molasses Corn Corn
-
5 .
5
15— —
50
1 - 49
1 - — 49
_ _ _ _~ __
-------
The results obtained with the various combinations of
additives and sludge which were ensiled are shown in Table
42. These results indicate that the pulp mill sludge is
very difficult to break down compared to regular feed
ensiling materials. Silage can be made from grass and
corn after a 30-day storage period. The additives, Johnson
grass and corn, formed silage, but the sludge remained
unchanged during the four-month period. The best looking
silage was No. 3 which contained 5$ molasses and 45$
Johnson grass and 50$ sludge.
In checking the palatability of these ensiled mixtures,
dairy steers consumed some of the first three mixtures
(silos No. 1, 2 and 3)^ but did not relish it very much.
The results indicate that sludge is not suitable for silage
making. Modification or partial degredation of the cellulose
material by acid or enzymes would probably result in
improved fermentation, but this would be a costly process.
Because of the low cost of cellulose-type feeds, it is
economically unattractive to modify the sludge. For
example, hay is presently selling for $14 to $20/ton in
the Camas-Washougal area.
Sludge Feeding Studies
In addition to the silage studies, rations containing
various amounts of sludge were fed to four groups of dairy
steers (approximately 300 Ib in weight) consisting of two
animals per group. The sludge used in these trials was
dried in a forced-air oven at 80° F. The dried material
was then ground in a hammermill so that it could be mixed
with the other ingredients in the grain ration. The
composition and chemical analyses of the rations were as
follows:
Quantity in Founds
Ingredient U II TTT TV
Corn 72 67 62 57
Cottonseed Meal 20 20 20 20
Sludge 0 5 10 15
Molasses 55 55
Steamed Bonemeal 22 22
Salt 1111
109
-------
TABLE Zj.2
SILAGE STUDY
After Ensiling (4 mos.)
H
O
Silo
No.
1
2
3*
4
5
6
7
8
Contents
50$ freshly cut Johnson grass
50^ paper by-product
5$» cottonseed meal
45$ Johnson grass
50$ paper by-product
5^ molasses
45$ Johnson grass
50$ paper by-product
\% urea
5$ molasses
44$ Johnson grass
50^ paper by-product
50^ ground corn
50$ paper by-product
1?& urea
49$ ground corn
50$ paper by-product
1% urea
49$ whole corn
50^ paper by-product
100^ paper by-product
Condition
Good Odor
Brown
Color &
Poor Odor
Good Odor
&
Color
Ammonia
Odor and
Dark Color
Poor Color
Pair Odor
Poor Color
and Odor
(NHo) Wet
Poor Color
and Odor
(NHU)
WetJ
Breakdown
of Sludge
None
None
Slight
Slight
None
None
Hone
Corn
Broken Down
None
pH
5.2
5.0
4.75
b.b1
4.4
8.7
8.6
7.45
*Best product.
-------
The four groups of dairy steers were fed the rations for .a
14-day period. No forage (hay, silage or pasture) was fed
so that the palatability and the value of the rations
could be checked.
The results of the cattle feeding studies are presented in
Table 43. The results indicate that the dried sludge is
not toxic to ruminants at levels up to 15$ of the grain
ration. However, it appears that the dried sludge has
very low feeding value since the steers lost more weight
as the percentage of sludge was increased in place of the
corn.
TABLE 43
GRAIN CONSUMPTION AND WEIGHT GAINS OR LOSSES
FOR DAIRY STEERS
Daily Feed Daily Weight
Sludge, Consumption Gain or Loss,
Ration # of Ration Ibs Ibs
I Control 0 15 +0.5
II 5 14 - 1.0
III 10 13 - 1.3
IV 15 11 1.5
The addition of 15$ sludge in the ration resulted in a
weight loss of about 21 Ibs in the two-week trial period.
The animals receiving Ration IV were actually about 28 Ibs
lighter than the controls. Again, it appears that hydrolysis
or modification of the cellulose is needed to make it
nutritionally available to ruminants. The pulp mill cellu-
lose sludge evidently is quite resistant to breakdown by
the microbial population in the rumen.
Ill
-------
CATTLE BEDDING
A small scale experiment was conducted to determine the
practicability of using clarifier sludge as a bedding
material for dairy cattle. Because of relatively heavy
winter rains in the Camas area dairy cattle become extremely
muddy if allowed to run in the fields. They are usually
confined in corrals with concrete slabs and generally have
access to a "loafing shed".
The dairy farm chosen for this evaluation had a "loafing
shed" comprised of a row of box stalls on each side and a
concrete runway through the center, extending the length
of the shed. The box stalls are 7 feet long and 4 feet
wide—sufficient room for a cow to lie down comfortably.
A gravel base was used in the stalls to allow moisture to
filter down.
At present dairy men preferably use wood shavings as
bedding material in the box stalls. The shavings are
thrown into the "head" end of the stall and gradually work
their way out the back onto a concrete slab where, along
with the manure, they are scraped up and hauled out to
the fields. Shavings are an excellent bedding material.
However, they are becoming increasingly scarce and
expensive—having jumped in price from $4.00 to more than
$5.00 per unit in the past year.
Three stalls were used in the experiment. About 11 Ibs of
sludge were used in each stall. This was good for four
days, after which time an equal amount was again thrown
into the head end of the stalls. After 4 days the third
and final application was made.
Performance of the material as a bedding was judged as
being satisfactory. It behaved in a similar fashion as
shavings in respect to movement to the clean-out area.
Sludge absorbed manure readily and as it became wet had a
tendency to stick less to the cow. In order to determine
sludge efficacy in keeping cows clean, a trial of consid-
erable duration would be required.
It costs about 2*r cents per day per stall for shavings.
Sludge would have to sell for less than $16.00 per ton
delivered in order to compete with shavings.
112
-------
GREENHOUSE APPLICATION
Sludge was evaluated as a potential component of synthetic
potting media widely used in containerized agriculture.
The containerized approach to production of ornamental
species has essentially eliminated the practice of adding
new soil to root area of the enlarging plant at each of
the several "repottings". The current nursery method
involves initial transplanting or seeding in a container
sufficiently large to accommodate plant size at market
stage. Potting medium requirements under these conditions
of continuous and long time use are different from those
of conventional or short time use. Synthetic soils should
then be equivalent to or better than typical soil mixtures
used for such purposes. These synthetic soils should
exhibit characteristics such as: be light in texture;
have low silt-clay content; have high water holding
capacity; be resistent to compaction; have an attractive
appearance; and present an environment unfavorable to plant
pathogens.
A fertilizer mixture containing urea 4 Ibs, superphosphate
4 Ibs, sulfate of potash 2 Ibs and limestone 2 Ibs was
incorporated into a cubic yard of soil. Standard green-
house potting soil employed in studies was a volume based
mixture of river loam-sand-peat moss at a ratio'of 7:2:5.
Potting media were wetted in excess and held overnight in
the greenhouse.
Standard vegetable and ornamental crop varieties were
planted into test media as seeds or transplants. Test
plants originating as rooted cuttings were transplanted
and maintained in greenhouse potting mixture for about one
month prior to use. The root ball of the cuttings were
freed of easily removed soil prior to transfer.
Standard potting soil, sand, peat moss, perlite, vermiculite,
clarifier sludge and bark dust were evaluated alone or in
various combinations as potting media.
Tests involving root knot nematode employed a standardized
method in which tomato transplants served as the host plant.
Heavily infested root knot soil maintained by continuous
cropping with tomato was used to prepare nematode infested
test soils. One volume soil inoculum was thoroughly mixed
with 3 volumes of standard potting soil. Sludge was mixed
with inoculated soil at 50, 100, and 200 T/A rates. Two
113
-------
Bonney Best tomato seedlings 4 to 5 cm tall were transplanted
in 2 inch plastic pots with sludge amended soils and control
soils, and were grown in the greenhouse for 4 to 6 weeks.
Rating of root knot, following removal of soil from around
plant roots, was made by evaluating relative gall size and
number of galls on roots.
As shown in Table 44 two synthetic potting mixtures,
using either vermiculite or perlite with sludge, were
satisfactory growth media for containerized production of
azalea, rose and zinnia. Greater size increases and
superior appearance of Douglas fir seedlings, however,
were obtained with all three component mixtures of sludge-
bark-sand. The sludge-vermiculite mixture in all combina-
tions tested were effective for tomato growth. Addition
of sand as a component produced tomato plants that were
superior to all other mixes.
Synthetic soil mixes with sludge as a component did not
add noticeably to the gross weight of synthetic media,
plant and container. The light weight characteristic of
synthetic soils is of considerable importance in growth
medium selection. Some nurserymen have abandoned standard
potting mixtures because of weight.
Limited studies were made on the availability of water for
plant growth in synthetic soils containing sludge and
standard potting soil. Measurement of water holding
capacity was made by observing the time interval between
water application and incipient wilt. With zinnia test
plants grown in sludge mixtures, wilting was delayed more
than 8 hours beyond that of standard soil.
The 200 T/A sludge amendment of root knot nematode inoculated
soil yielded tomato plants nearly free of root galls. Data
shown in Table 45 indicate reducing sludge application
from 200 T/A to 100 T/A and 50 T/A reduced disease control
from 98$ to 77$ and 71$ respectively. Varied organic
amendments have been reported effective in nematode disease
control and include chitin, straw, activated sludge and
waste paper (6).
114
-------
TABLE W
COMPARISON OP PLANT GROWTH IN STANDARD SYNTHETIC: AND
SLUDGE-BASED POTTING MEDIA
Test Plant and
Potting Media
Av.alae Plant
"HStandard Media
2. Sludge-Vermiculite
1:1
1:2
2:1
?:1
3. Sludge Only
•I-. Vormiculitc Only
Pour.las Fir Seedlings (^)
TIStandard Media
2. Sludge-Bark
1:1
1:2
1:3
2:1
3. .Sludge-Bark-Sand
1:1:1
1:2:1
1:3:1
1:2:2
1:2:3
4. Sludge Only
5. Bark Only
6. Sand Only
Plant
Growth
Rating
3
2
1
1'.
3
•3
2
3
3
Test Plant and
Potting Media
Tomato Plant (3)
1'."" Standard Media
2. Sludge-Sand
1:1
1:2
1:3
2:1
3:1
3. Sludge-Vermiculite
1:1
1:2
v- ?
-1- • j
2:1
3:1
Ji. Sludge-Perlite
1:1
1:2
1:3
2:1
3:1
5. Sludge-Sand-Vermiculite
1:1:1
6. Sludge-Sand-Perlite
1:1:1
7. Sludge-Sand
1:1
1:2
1:3
8. Sludge Only
9. Verraiculite Only
10. Perlite Only
11. Sand Only
Plant
Growth
Hating
3
2
3
3
2
1
3
3
2
2
2
2
2
2
3
3
1
2
2
2
(l) Azalae test duration - 8 weeks.
(2) Douglas fir test duration - 6 months.
(3) Tomato test duration - 7 weeks.
(4) Number 4 equals highest rating.
115
-------
TABLE 45
INFLUENCE OP SLUDGE ON CONTROL OF TOMATO
ROOT KNOT NEMATODE
Sludge Addition Average Number Percent Gall Standard
(Tons/A) of Galls Reduction Deviation
0 91 — 26
50 26 71 17
100 21 77 7
200 5 98 5
Nematode control resulting from decomposition of organic
soil amendments has been widely observed. Amendments in
biological control have not provided sufficient control to
satisfy farm requirements. Comparative control of sludge
to other amendments is not known.
116
-------
SECTION XIII
A CKNOWLEDGMENTS
The authors wish to acknowledge the help and cooperation
given by Crown Zellerbach management and personnel.
Those involved at the mills were:
Mr. J. B. Palmer, Camas Mill Manager
Mr. T. I. Meehan, Sr., Camas Mill Manager
Mr. J. J. Goss, Port Townsend Mill Manager
Engineering, maintenance and operational problems were
handled by Messrs A. 0. Muench, P. Vajda, W. Worvell,
B. C. Smith, M. Dulley, B. Jessett, P. Williams and
H. Hamby of the Camas Mill.
Installation of incinerator and sludge drying facilities
were by Reitz Manufacturing personnel Mr. T. Yamada ana
associates.
The technical aspects of the evaluation program were
undertaken at the Crown Zellerbach Central Research
Division and Environmental Services Division by the
following personnel:
Dr. H. R. Amberg, Director, Environmental Services
Division (Project Officer)
Dr. T. R. Aspitarte, Manager, Environmental Services
Division
Mr. A. S. Rosenfeld, Research Engineer, Environmental
Services Division
Dr. B. C. Smale, Senior Research Biologist,
Environmental Services Division
Dr. J. F. Cormack, Supervisor, Environmental Services
Division
Mr. J. G. Coma, Supervisor, Central Research Division,
Process Engineering
Mr. 0. L. Hamblen, Technician
Mr. R. Bafus, Technician
Mr. H. Husby, Technician
Mr. C. Esser, Technician
117
-------
The support of the project by the Environmental Protection
Agency and the help provided by Dr. L. W. Weinberger and
Mr. G. R. Webster is gratefully acknowledged. We were
particularly pleased with the help and guidance provided
by Mr. R. H. Scott, the project officer and Dr. H. K.
Willard of the Pacific Northwest Research Laboratory
located at Corvallis, Oregon.
The helpful suggestions of Dr. C. Fordyce, Jr., Plant
Pathologist USDA at Beltsville, Maryland, concerning morel
culture were appreciated.
118
-------
SECTION XIV
REFERENCES
1. Coogan, F. J. and Stoval, J. H., "Incineration of
Sludge from Kraft Pulp Mill Effluents,11 Tappi3 40
No. 6, pp 9^A-96A (19b5).
2. Bollen, W. B. and Lu, K. C., "Effect of Douglas Fir
Sawdust Mulches and Incorporations on Soil Microbial
Activities and Plant Growth," Soil Science Society
American Proceedings, 21, pp. 35-41 (1957).
3. Stephenson, R. E. and Schuster, C. E., "Laboratory,
Greenhouse and Field Methods of Studying Fertilizer
Needs," Soil Science, 52, pp. 137-153 ' ' '
4. Li, J. C. R., "Introduction to Statistical Inference,"
Printed by Edwards Brothers Inc., Ann Arbor, Michigan
(1957).
5. Fordyce, C. Personal Communication. U. S. Department
of Agriculture, Beltsville, Maryland, (1970).
6. Good, J. M., "Bionomics and Integrated Control of Plant
Parasitic Nematodes." Journal of Environmental Quality,
1, No. 4, pp. 382-386, (1972).
119
-------
SECTION XV
APPENDICES
Page No,
Tables
I Sludge Decomposition as Measured by
Carbon Evolution with Soil Respi-
rometers. Experiment 1. 123
II Sludge Decomposition Measured as
Percent Evolved with Soil Respi-
rometers. Experiment 1. 124
III Sludge Decomposition as Measured by
Carbon Evolution with Soil Respi-
rometers. Experiment 2. 125
IV Sludge Decomposition Measured as
Percent Evolved with Soil Respi-
rometers. Experiment 2. 126
V Greenhouse Studies to Determine Effect
of Sludge and Supplemental Nitrogen on
Sunflower Growth. 127
VI Total Quality Scores of 1970-1972 Corn
and Bean Crops on Tolerance and Yearly
Amendment Design Plots 128
VII Effect of Clarifier Sludge on Corn
Yield in Field Plot Tolerance Studies 129
VIII Effect of Clarifier Sludge on Bean
Yield in Field Plot Tolerance Studies 130
IX Effect of Clarifier Sludge on Corn
Yield in Field Plot Yearly Amendment
Studies 131
X Effect of Clarifier Sludge on Bean
Yield in Field Plot Yearly Amendment
Studies 132
XI Strawberry Yields Under Mulch
Conditions—1972 Crop 133
121
-------
Page No,
XII Raspberry Yields Under Mulch
Conditions--1972 Crop 134
Figures
1A Material Balance Formula 135
2A First Sunflower Crop 136
3A Second Sunflower Crop 137
4A Third Sunflower Crop 138
5A Fourth Sunflower Crop 139
122
-------
TABLE I
SLUDGE DECOMPOSITION AS MEASURED BY CARBON EVOLUTION
WITH SOIL RESPIROMETERS. EXPERIMENT 1.
LO
Sludge
Addition
(Tons/Acre )
0
50
100
150
200
50
50
100
100
150
150
200
200
0
0
0-
0
Nitrogen
Addition
(C:N)
0
0
0
0
0
25:1
100:1
25:1
100:1
25:1
100:1
25:1
100:1
1*
2*
3*
4*
30 Days
Sandy
14
128
155
286
250
1115
726
1496
1142
1578
1179
1938
1364
9
13
17
21
Clay
75
579
781
842
910
1031
846
1439
1115
1319
967
1408
932
86
71
65
75
Milligrams Carbon Evolved
50 Days
Sandy
24
258
361
647
553
1721
1044
2228
1467
2879
1527
3865
1810
23
28
22
28
Clay
141
1111
1864
1966
2459
1447
1310
2335
1968
2076
1630
2039
1627
151
124
129
100
90 Days
Sandy
33
369
566
996
854
2017
1238
2752
1785
3740
1959
4857
2320
47
36
29
41
Clay
181
1663
2550
2566
3526
1671
1736
2952
2627
2810
2305
2625
2339
200
166
189
138
120 Days
Sandy
39
490
653
1414
1115
2176
1414
3210
2040
4352
2448
5440
2856
204
57
150
131
Clay
272
1958
3264
3060
4216
1850
1958
3482
3128
3427
2815
3074
2992
245
296
277
199
*Same nitrogen amount used for
3* 150 T/A - 25:1, 4* 200 T/A
50 T/A - 25:1. 2* 100 T/A - 25:1.
25:1.
-------
TABLE II
SLUDGE DECOMPOSITION MEASURED AS PERCENT EVOLVED
WITH SOIL RESPIROMETERS. EXPERIMENT 1.
ro
Sludge
Addition
(Tons/Acre)
50
100
150
200
50
50
100
100
150
150
200
200
Nitrogen
Addition
(C:N)
0
0
0
0
25:1
100:1
25:1
100:1
25:1
100:1
25:1
100:1
30 Days
Sandy
3.6
2.1
2.7
1.8
31.8
20.7
21.3
16.5
15.0
11.2
13.8
9.7
Clay
16.5
11.1
8.0
6.5
29.4
24.1
20.4
15.9
12.5
9.2
10.0
6.7
Percent Sludge Decom]
bO Days
Sandy
7.4
5.1
6.1
3.9
49.0
29.7
31.7
20.9
27.3
14.5
27.5
12.9
Clay
31.7
26.6
18.7
17.5
41.2
37.3
33.3
28.0
19.7
15.5
14. 5
11.6
90 I
Sandy
10.5
8.1
9.5
6.1
57.5
35.3
39.2
25.4
35.5
18.6
34.6
16.5
Dosed
!>ays
Clay
-_j **
47.4
36.3
24.4
25.1
47.6
49.5
42.0
37.4
26.7
21.9
18.7
16.7
120 Days
Sandy
14.0
9.3
13.4
7.9
62.0
40.3
45.7
29.1
4l.3
23.2
38.7
20.3
Clay
i "
55.8
46.5
29.1
30.0
52.7
55.8
49.6
44.6
32.5
26.7
21.9
21.3
-------
TABLE III
SLUDGE DECOMPOSITION AS MEASURED BY CARBON EVOLUTION
WITH SOIL RESPIROMETERS. EXPERIMENT 2.
VJi
Sludge
Addition
(Tons/Acre)
0
100
200
400
600
100
100
100
200
200
200
400
400
400
600
600
600
Nitrogen
Addition
(C:N)
0
0
0
0
0
10:1
20:1
40:1
10:1
20:1
40:1
10:1
20:1
40:1
10:1
20:1
40:1
Milligrams Carbon Evolved
30
Sandy
21.1
78
306
195
187
1162
1036
1090
1402
1716
1234
1143
1276
1040
1150
997
941
Days
Clay
29
663
662
442
187
1201
1527
1269
1453
1808
1789
2434
2864
2211
2129
2024
728
60
Sandy
22.9
209
643
412
305
2159
2095
1755
3134
3498
2121
2312
2888
2889
2120
2443
2162
Days
Clay
81
1731
2410
1280
3^4
2121
2311
2092
3191
3396
2932
4988
4754
3711
3598
3092
1481
90
Sandy
23.5
308
886
530
409
2782
2535
2035
4374
4635
3084
3324
4416
3622
2997
3658
3418
Days
Clay
175
2413
3980
2197
694
2787
2785
2717
4309
4162
4159
5817
5528
4678
4273
3673
20
120
Sandy
25.3
519
1328
787
671
3213
2988
2399
5404
5778
3678
4331
5732
4099
3678
4213
4448
Days
Clay
219
3087
5324
3770
1208
3345
3206
3234
5045
4791
4793
6205
6062
5469
4961
4190
2391
-------
TABLE IV
SLUDGE DECOMPOSITION MEASURED AS PERCENT EVOLVED
WITH SOIL RESPIROMETERS. EXPERIMENT 2.
Sludge
Addition
(Tons/Acre)
100
200
400
600
100
100
100
200
200
200
400
400
400
600
600
600
Nitrogen
Addition
(C:N)
0
0
0
0
10:1
20:1
40:1
10:1
20:1
40:1
10:1
20:1
40:1
10:1
20:1
40:1
Percent Sludge Decomposed
30
Sandy
1.1
2.2
1.4
1.8
16.6
14.8
15.5
10.0
12.2
8.8
8.1
9.1
7.4
10.9
9.5
9.5
Days
Clay
9.5
4.7
3.1
1.8
17.1
21.8
18.1
10.3
12.9
12.7
17.3
20.4
15.8
20.2
19.2
6.9
bO
Sandy
2.9
4.6
2.9
2.9
30.8
29.9
25.0
22.3
24.9
15.1
16.5
20.6
20.6
20.1
23.2
20.5
Days
Clay
24.7
17.2
9.1
3.3
30.2
32.9
29.8
22.8
24.2
20.9
35.5
33.9
26.4
34.2
29.4
14.1
90
Sandy
4.4
6.3
3.8
3.9
39.6
36.1
29.0
31.2
33.0
22.0
23.7
31.5
25.8
28 5
34! 8
32.5
Days
Clay
3^.4
28.4
15.7
6.6
39.7
39.7
38.7
30.7
29.7
29.6
41.4
39.^
33.3
40.6
3^.9
19.5
120
Sandy
7.5
9.5
5.6
6.4
45.8
42.6
34.2
38.5
41.2
26.2
30.9
40.8
29.2
34.9
40.0
42.3
Days
Clay
44.0
37.9
26.9
11.5
47.7
45.7
46.1
35.9
35.0
34.1
44.2
43.2
40.0
47.0
39.8
22.7
-------
H
ro
TABLE V
GREENHOUSE STUDIES TO DETERMINE EFFECT OF SLUDGE AND SUPPLEMENTAL
NITROGEN ON SUNFLOWER GROWTH
Treatment
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Sludge
Tons/A
0
50
100
150
200
50
50
100
100
150
150
200
200
0
0
0
0
Additional
Nitrogen
0
0
0
0
0
25:1
100:1
25:1
100:1
25:1
100:1
25:1
100:1
1
2
3
4
Yield — Grams Sandy Soil
1st
Crop
2.0
1.7
1.8
1.6
1.5
1.4
1.7
3.1
2.0
2.0
2.0
1.9
2.2
2.5
0.4
0
0
2nd
Crop
1.5
1.7
2.2
1.9
2.2
2.4
1 Q
7.8
2.4
7.5
2.3
6.5
2.1
2.5
1.7
1.9
0.7
3rdT
Crop
2.2
2.2
2.3
2.5
2.3
4.6
2.3
5.4
2.8
7.7
2.9
10.2
2.5
5.9
4.7
4.0
3.0
4th
Crop
1.8
1.5
1.6
1.7
1.6
2.4
1.8
4.0
1.3
2.7
1.9
1.9
l.l
1.2
2.6
0
0
Mean
1.88
1)78
1.98
1*93
1.90
2.70
1.93
5.08
2.13
4.98
2.28
5.13
1.98
3.03
2.35
1.48
0.93
1st
Crop
7.7
1.5
1.3
1.6
1.6
2.6
1.6
5.8
1.4
5.7
1.5
5.1
1.4
5.4
4.3
1.0
0
Yield — Grams
2nd
Crop
1 n mm
2.2
1.7
2.2
2.8
2.5
5.6
1.8
5.9
1.6
5.5
2.0
6.6
2.3
1.0
0.8
0.5
0
3rd
Crop
4.2
2.7
2.7
2.9
3.4
11.9
6.6
13.2
5.0
10.7
3.0
8.1
4.0
6.2
0.9
0.5
1.4
Clay Soil
4th
Crop
4.4
3.6
1.3
1.3
1.2
5.3
4.6
6.1
6.6
4.8
7.3
4.8
6.7
5.2
1.8
0
0
Mean
4.6^
2.35
2!l5
2.18
6.35
•3.65
7.75
3.65
6.68
3.45
6.15
•3.60
4.45
1.95
0.50
0.35
(I), (2), (3) and (4) equivalent nitrogen added in Treatments 6, 8, 10 and 12 respectively.
-------
TABLE VI
TOTAL QUALITY SCORES OF 1970-1972 CORN AND BEAN CROPS ON
TOLERANCE AND YEARLY AMENDMENT DESIGN PLOTS
H
ro
CD
Tolerance Design
Sludge
T/A
0
0
0
0
200
200
200
200
400
400
400
400
600
600
600
600
Nitrogen
Addition
Ibs
91.6
18.3
9.2
0
C:N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Corn
Plot
No.
1A
IB
1C
ID
2A
2B
2C
2D
3A
3B
3C
3D
4A
4B
4C
•to
70
0
14
15
18
2
16
18
12
0
12
16
9
0
12
12
7
11
8
16
16
16
18
18
19
17
19
19
19
19
19
19
19
19
72
-
14
17
16
18
17
17
16
18
18
17
16
20
20
20
20
Plot
No.
5A
5B
5C
5D
6A
6B
6C
6D
7A
7B
7C
7D
8A
8B
8c
8D
Beans
70 71
1 (1)
9
11
17
6
12
14
10
0
10
12
9 ,
0
11
11
8
72
3
10
14
15
6
17
17
17
16
17
18
17
16
19
19
18
Sludge
T/A
0
0
0
0
100
100
100
100
200
200
200
200
400
400
400
400
Yearly Amendment
Nitrogen
Addition
Ibs
45.8
9.2
4.6
0
C;N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Design
Corn
Plot
No.
9A
9B
9C
9D
10A
10B
IOC
10D
11A
11B
11C
11D
12A
12 B
12 C
12D
70
0
14
15
18
7
16
19
19
2
16
18
12
0
12
16
9
71
14
18
15
16
17
19
17
12
3-3
l4
14
4
10
13
13
3
72
0
19
13
15
14
10
7
8
6
4
3
2
12
14
13
10
Plot
No.
13A
13B
13 C
13D
14A
14B
14 C
14D
15A
15B
15 c
15D
16A
16B
16 c
16D
Beans
70 71
0 (1)
9
11
17
6
13
16
20
6
12
14
10
0
10
12
9
72
0
6
10
10
7
14
12
6
5
6
6
6
11
8
8
8
(1) TQS not determined for 1971 crop.
-------
TABLE VII
EFFECT OF CLARIFIER SLUDGE ON CORN YIELD
IN FIELD PLOT TOLERANCE STUDIES
2A
2B
2C
2D
3A
3B
3C
3D
4A
4B
4C
4D
Sludge
Tons /A
0
0
0
0
200
200
200
200
400
400
400
400
600
600
600
600
Nitrogen
Addition
Lbs-N
91.6
18.3
9.2
0
C;N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Pounds Corn
1970
1.9
27.8
33.5
55.5
0
32.7
69.9
46.9
0
41.4
^7.3
24.7
0
26.4
3^.5
21.5
1971
1.5
20.2
27.3
26.3
3^.0
44.1
35.0
34.8
47.6
52.9
51.5
^7.3
35.7
46.5
^9.3
46.4
1972
12.6
25.7
33.3
28.4
30.6
35.0
39.0
32.7
41.7
42.8
43.4
28.9
50.9
48.6
45.6
46.8
3 Years
Total
16.0
73.7
9^.1
110.2
64.6
ill. 8
22:2
89.3
137.1
142.2
100.9
86.6
121.5
129.4
114.7
129
-------
TABLE VIII
EFFECT OF CLARIFIER SLUDGE ON BEAN YIELD
IN FIELD PLOT TOLERANCE STUDIES
6A
6B
6C
6D
7A
7B
7C
7D
8A
8B
8C
8D
Sludge
Tons/A
0
0
0
0
200
200
200
200
400
400
400
400
600
600
600
600
Nitrogen
Addition
Lbs-N
91.6
18.3
9.2
0
C;N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Pounds Beans
1970
0
3.1
17.1
32.2
0.1
5.8
26.1
21.8
0
1.4
5.0
7.3
0
2.7
5.4
2.8
1971
0.3
4.6
13.1
17.4
0.3
18.4
23.4
21.2
1.8
19.3
26.8
20.1
2.6
24.4
27.4
20.1
1972
0.4
8.8
22.2
17.9
0.8
28.5
31.2
31.5
30.1
33.7
30.7
27.9
30.5
39.1
42.7
38.5
3 Years
Total
0.7
16.5
52.4
67.5
1.2
52.7
80.7
74.5
31.9
54.4
62.5
55.3
33.1
66.2
75.5
61.4
130
-------
TABLE IX
EFFECT OF CLARIFIER SLUDGE ON CORN YIELD IN FIELD PLOT
YEARLY AMENDMENT STUDIES
H
(jJ
H
Sludge
Tons/A
0
0
0
0
100
100
100
100
200
200
200
200
400
400
400
400
1970
N-Addition
Lbs-N
45.8
9.2
4.6
0
C:N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Lbs-
Yield
3.0
29.9
42.8
51.8
10.3
49.1
52.4
55.8
4.0
39.3
47.5
54.1
0
28.0
42.0
27.6
1971
N-Addition
Lbs-N
18.3
9.2
4.6
0
C;N
50:1
100:1
200:1
0
50:1
100:1
200:1
0
50:1
100:1
200:1
0
Lbs-
Yield
0
47.2
40.3
32.8
31.6
40.5
13.4
0
6.4
6.0
0.5
0.5
5.8
3-7
3.6
1.2
1972
N-Addition
Lbs-N
18.3
9.2
4.6
0
C:N
50:1
100:1
200:1
0
50:1
100:1
200:1
0
50:1
100:1
200:1
0
Lbs-
Yield
0
6.9
32.0
30.8
37.8
39.8
27.5
21.4
6.1
4.3
3.1
2.6
32.9*
28.3*
35.3*
27.8*
10A
10B
IOC
10D
11A
11B
11C
11D
12A
12B
12 C
12D
*Was not possible to add 400 T/A rate for third year.
for experimental design.
Values not consistent
-------
TABLE X
EFFECT OF CLARIFIER SLUDGE ON BEAN YIELD IN FIELD PLOT
YEARLY AMENDMENT STUDIES
ro
ft ^ ^
Sludge
Tons/A
0
0
0
0
100
100
100
100
200
200
200
200
400
400
400
i
400
1970
N- Addition
Lbs-N
45.8
1:1
0
C:N
10:1
50:1
100:1
0
10:1
50:1
100:1
0
10:1
50:1
100:1
0
Lbs-
Yield
0.1
17.9
33.2
37.2
0.2
27.3
41.4
40.3
0
10.4
36.0
34.3
0
1.6
4.8
6.0
1971
N-Addition
Lbs-N
18.3
9.2
4.6
0
C:N
50:1
100:1
200:1
0
50:1
100:1
200:1
0
50:1
100:1
200:1
0
Lbs-
Yield
0
7-9
24.5
22.6
0.9
19.0
15.9
6.7
0.3
7.5
8.1
2.1
3.8
1.5
0.9
0
1972
N-Addition
Lbs-N
18.3
9.2
4.6
0
G:N
50:1
100:1
200:1
0
50:1
100:1
200:1
0
50:1
100:1
200:1
0
Lbs-
Yield
0
4.5
9.2
27.4
2.1
19.3
X — '
18.7
5.3
0.6
1.7
w i
1.2
1.8
16.0*
6.1*
6.7*
4.7*
14A
14B
14C
14D
15A
15B
15 C
15D
16A
16B
16C
16D
*Was not possible to add 400 T/A rate for third year.
experimental design.
Values not consistent for
-------
TABLE XI
STRAWBERRY YIELDS UMDER MULCH CONDITIONS—1972 CROP
CO
u>
Treatment
Control
Plot IB
Plot 2C
Plot 4B
Total
1.5" Layer
Plot 1A
Plot 2B
Plot 3A
Total
3.0" Layer
Plot 2A
Plot 3C
Plot 4C
Total
5.0" Layer
Plot 1C
Plot 3B
Plot 4A
Total
16
-S
7
8
8
5
2
35
26
-85
7
21
9
10
85
56
67
33
52
134
33
33
26
-52-
15
19
27
-51
8
28
24
9
23
18
"35
123
147
59
95
78
64
84
86
105
275
45
102
52
64
99
5BH
42
48
88
67
30
95
ri
44
92
81
517
46
78
0
34 37
18
33
37
HSB
40
-s
26
50
51
157
155
17
17
35
467
614
608
T5B9~
289
5
283
465
455
-------
TABLE XII
Treatment
Control
Plot IB
Plot 2C
Plot 4B
Total
2" Layer
Plot 1A
M Plot 2B
u> Plot 3A
•^ Total
•er
4"
Plot
Plot 3C
Plot 4C
Total
6" Layer
Plot 1C
Plot 3B
Plot 4A
Total
RASPBERRY YIELDS UNDER MULCH CONDITIONS— 1972 CROP
O/22
7
3
8
IH
8
3
7
TB
10
7
4
2T
5
5
5
15
b/25
12
5
14
10
4
10
2T
13
9
11
33
8
8
11
57
t>/2b
31
14
22
57
17
10
28
55
20
34
21
75
17
30
13
55
b/30
17
28
24
55
25
7
7T
17
36
17
75
29
43
21
53
Days
7/3
35
28
31
32
8
46
35
38
56
27
12T
27
67
37
13T
Picked — Yield in Ounces
7/5
20
12
6
3S
21
2
19
32-
8
24
17
17
34
17
5B~
7/8^
33
17
14
44
__
22
55
22
55
34
ITT
32
71
34
137
7/10
11
12
8
3T
18
__
23
13
28
15
55
8
30
12
50-
7/13
15
17
17
15
3
22
3(J
10
31
14
55
10
31
18
55
7/15
11
15
11
37
15
17
32-
9
28
10
9
29
11
35
7/17
11
19
9
26
•> ••
25
5T
7
26
15
13
50
17
HO"
7/21
5
8
il
19
19
3H
4
33
5
3?
9
46
15
70-
Total
208
178
169
555
250
37
277
553
171
367
190
184
444
211
-------
MATERIAL BALANCE FORMULA
Basic Requirement: Measure all consistencies and one wt/unit
time. Example below is for a sludge filter, but could be for a
clarifier, press, or dryer.
Clarifier Underflow
X
Cons. =
Filter Cake
Filtrate—measure wt/unit time
A Cons. = C2
LetX
Y
A
Wt. Clarifier flow/unit time
Wt. filter cake/unit time
Wt. filtrate/unit time—measured
Total Weight Balance
Solids Balance
Substituting for X
Solve for Y
and
Cj(Y + A)
Y
X
Y + A
C3Y + C2A
C3Y + C2A
AJCZ_1C1| All
Knowns
Y + A
FIGURE 1A
135
-------
U)
r>^
R-
***%
4***
ii
1
—rau
• ttq^pcrwirre
MILK MILK
8
14 15 16 17
10 11
12
13
14 15
16 17
FIGURE 2A FIRST SUNFLOWER CROP.
-------
10 11 12 13 14 15
f
:J3n >
16 17
UJ
i
MILK
*»<-- *A~
J
I &&. I ^_^» i
8
'11 *f-.ij J
•
10 11 12 13 14
15
16 17
FIGURE 3A SECOND SUNFLOWER CROP.
-------
H
U>
00
15 16 17
8
10
11 12 13 14 15
16 17
FIGURE4A, THIRD SUNFLOWER CROP,
-------
-f A'^>
V* . i
UO
16 17
FIGURE 5A FOURTH SUNFLOWER CROP.
-------
SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
/. Report No.
3. Accession No.
W
4. Title
METHODS FOR PULP AND PAPER MILL SLUDGE
UTILIZATION AND DISPOSAL
7. Author(s) Thomas R. Aspitarte, Alan S. Rosenfeld,
Bernard C. Smale, Herman R. Amberg
5. Report Date
6.
8. Performing Organization
Report No.
10. Project No.
9. Organization
Crown Zellerbach Corporation
i Environmental Services Division
I Camas, Washington
i
1 './.. Sponsoring Organization
'i. Supplementary Notes
Environmental Protection Agency Report No. EPA-R2-73-232, May 1973
11. Contract!Grant No.
12040 ESV
13, Type of Report and
Petiotl Covered
Final Report for period
May 1968 - May 1973 \
16. Abstract
The disposal of pulp and paper mill sludge in a manner which has minimal
effect on the environment has become a serious problem. This project
was carried out to evaluate four methods of disposal, namely:
(1) incineration in an air entrained dryer-incinerator, (2) burning in
hog fuel boilers, (3) incorporation into soil as an amendment, and
(4; hydromulching for soil stabilization. Other possible uses are
discussed. Burning sludge in incinerators costs between $11 and $13/dry
ton, including all prior dewatering steps. Sludge can be made available
at various degrees of dewatering at costs of from $7 to $20/dry ton.
Incorporation into farm soil offers the possibility for disposal of
large quantities of sludge. At low levels (100-200 tons/acre) crop
yields are satisfactory, provided adequate nitrogen is added. A high
level incorporation (600 tons/acre) requires a year of fallow preceding
crop planting. Sludge alone or in combination with bark can be used
as a hydromulch in establishing grass stands on steep embankments.
17a. Descriptors
Sludge Disposal*, Soil Treatment*, Agriculture, Industrial Wastes,
Pulp Wastes*, Sludge*, Wood Wastes*, Capital Costs, Operating Costs
Crop Production*, Decomposing Organic Matter, Effluents, Odor, Phyto-
toxicity, Solid Wastes, Camas Washington, Crown Zellerbach Corp.,
Cattle Feed, Cattle Bedding, Nematode Control, Morel Growth, Synthetic
Potting Media
17c. CO WRR Field & Group 05E
18. Availability
19. Security Class.
(Report)
20. Security Class.
(Page)
21. No. of
Pages
22. Price
Send To:
WATER RESOURCES SCIENTIFIC INFORMATION CENTC*-
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON, D, C. 20240
Abstractor Thomas R. Aspitarte \Institution
102 (REV JUNE 1971)
SPO 913.?» f
------- |