United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
EPA-600/8-79-031a
November 1979
Research and Development
Participate Control
Highlights:
Recent Developments
in Japan
IhCHNICAL DOCUMENT COLLECTION
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories 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 nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the SPECIAL REPORTS series. This series is
reserved for reports which are intended to meet the technical information needs
of specifically targeted user groups. Reports in this series include Problem Orient-
ed Reports, Research Application Reports, and Executive Summary Documents.
Typical of these reports include state-of-the-art analyses, technology assess-
ments, reports on the results of major research and development efforts, design
manuals, and user manuals.
EPA REVIEW NOTICE
This report has been reviewed by the U.S. Environmental Protection Agency, and
approved for publication. Approval does not signify that the contents necessarily
reflect the views and policy of the Agency, nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/8-79-031a
November 1979
Particulate Control Highlights:
Recent Developments in Japan
by
Dennis C. Drehmel, Charles H. Gooding (RTI),
and Grady B. Nichols (SoRI)
U.S. Environmental Protection Agency
Office of Environmental Engineering and Technology
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711 .
Program Element No. EHE624A
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
-------
ABSTRACT
This report describes the results of visits in Japan to assess
research and development of new particulate control technology, and to
evaluate the applicability of the Aut-Ainer particulate control device
to diesel engines.
New technology observed includes hooding systems for coke oven
charging and pushing, fugitive emissions control in a Q-BOP furnace
building, novel electrostatic precipitators (ESPs), magnetic separators,
and hybrid control devices. Fugitive emissions in two iron and steel
plants visited are well controlled. Fugitive emissions are prevented by
road watering and process hooding. Fugitives within a large building
are collected by a special lightweight ESP. Novel ESPs utilize approaches
such as wide plate spacing, advanced charging systems, and water cooled
collection electrodes. Magnetic separators are currently used for water
pollution and are under consideration for air pollution control.
The Aut-Ainer has evolved from an experimental approach to the
uevice development stage over several years. The device currently has
limited applicability to particulate control from diesel engines. However,
its basic collection characteristics seem to be based on sound principles;
with a limited amount of additional development in the general area of
removing the previously collected material, the device seems promising.
11
-------
CONTENTS
Abstract ii
Figures iv
Tables iv
Introduction 1
Conclusions 2
Recommendations 3
Summaries of Japanese Technology 4
Mitsubishi Heavy Industries Company 4
Nippon Steel Corporation 6
Onoda Cement Company 7
Idemitsu Kosan Company 12
Kawasaki Steel Corporation 15
18
Dai do Steel Company 20
Hitachi, Ltd. 26
University of Tokyo 28
Eikosha Company 29
Mitsubishi Motors Corporation 39
Japan Automobile Research Institute 43
iii
-------
FIGURES
No,.
1 Wide plate spaced precipitator at Onoda Cement Company 8
2 ' Stack and back side of Onoda electrostatic precipitator 9
3 Hybrid precipitator at Onoda Cement Company 11
4 Cold electrode electrostatic precipitator at Idemitsu Kosan Company 13
5 Cold water piping and hoppers for Idemitsu precipitator 14
6 Roof-mounted precipitator at Kawasaki's Chiba Works 16
7 Magnetic filter at Kawasaki's Chiba Works 19
8 Magnetic filtration system at Dai do Steel Company 21
9 Close-up of Daido Steel magnetic filter 22
10 Power supply for Daido Steel magnetic filter 23
11 Opening Aut-Ainer after road test 36
12 Removing internals from Aut-Ainer collector 37
13 Throttle plates and mesh packing 38
14 Experimental setup at Mitsubishi Motors 40
15 Close-up of Aut-Ainer 41
16 View of primary and secondary collectors 42
TABLES
No. Page
1 Parameters of Onoda Precipitators 10
2 Comparison Between HGMF and Other Methods of Filtration 24
3 Summary of Application of HGMF for Steel Mill Waste Waters 27
IV
-------
INTRODUCTION
Many problem areas in particulate control can be found in both the
United States and Japan. For example, both countries are oil importers
and look forward to partially solving future energy needs by burning low
sulfur coal. In the United States, low sulfur coal is abundant in the
western states. Use of low sulfur western coal in power plants with
electrostatic precipitators designed for high sulfur coal has led to
increased particulate emissions because of increased resistivity associated
with fly ash from low sulfur coal. The low sulfur coal used in Japan
comes from Australia. The Japanese have been anticipating problems with
collection of low sulfur coal fly ash and are developing new electrostatic
precipitator designs to overcome the problems. In another energy related
area, both the United States and Japan increase fuel economy for transportation
by using diesel engines. However, particulate emissions from diesel
engines may be two orders of magnitude higher than those from gasoline
engines. The increased particulate emissions would be at the worst
location—in cities, near large numbers of people who would be directly
exposed.
Both the United States and Japan are leading producers of iron and
steel. Consequently, both face the problems of the magnitude and complexity
of emissions from the iron and steel industry. While control of ducted
sources has tended to improve, control of emissions from coke ovens, hot
metal transfer, sinter plant fugitives, storage piles, and roads has
been difficult. In Japan, new ideas in hooding and control devices are
leading to the solution of some of these fugitive emission problems.
Because of the similarity of particulate control problems and the
need to share technology which could provide solutions, a team of particulate
control specialists, who are the authors of this report, visited Japanese
companies and research organizations during May 1979. This report
summarizes the information received and is intended to stimulate technology
transfer. To that end, the authors will provide more detailed information
upon request and have noted personnel contacted so that others may
establish direct information exchange.
-------
CONCLUSIONS
Japanese firms concerned with controlling high resistivity particulate
matter include Mitsubishi Heavy Industries Company, Hitachi, Ltd.,
Idemitsu Kosan Company, and Nippon Steel Corporation. A number of different
approaches have been taken by these firms, including the use of prechargers,
cooled collection electrodes, and increased sectionalization. Use of
prechargers may not only solve high resistivity problems but also reduce
costs over conventional design. The latter two options may reduce costs
compared to a precipitator of equal performance but are expensive on an
absolute scale.
Japanese firms concerned with controlling diesel emissions include
Eikosha Company, Mitsubishi Motors Corporation, and the Japan Automobile
Research Institute. The Eikosha Company has evolved a control device
which consists of a primary and a secondary collector. The first agglomerates
the particles and diverts them to the secondary collector. The secondary
collector is a glass bag filter which may be dumped. The Japan Automobile
Research Institute is experimenting with a diesel engine which uses both
alcohol and diesel fuel. This reduces emissions and conserves diesel
fuel. Both approaches have been tested and will reduce emissions by at
least 50 percent.
Japanese firms developing or using new concepts for particulate
control include Kawasaki Steel Corporation, Daido-Steel Company, Hitachi, Ltd.,
Onoda Cement Company, and Mitsubishi Heavy Industries Company. New
concepts include magnetic filtration, electric coagulation, and roof-
mounted, hybrid, or wide plate spaced precipitators. Use of magnetic
filtration for cleaning iron and steel waste waters lowers operating and
installation costs compared to other systems. Use of wide plate spaced
precipitators involves lower capital costs because of the fewer number
of plates and accessories. Roof-mounted precipitators can control
emissions from large shops in the iron and steel industry. This is
especially important where some fugitive emissions can be contained only
by the shop building itself.
-------
RECOMMENDATIONS
1. The applicability of Japanese techniques for fugitive participate
control in the U.S. should be surveyed.
2. Japanese approaches for diesel particulate control should be
tested under EPA supervision.
3. Development of the diesel fuel/alcohol engine should be encouraged.
4. Parallel efforts in magnetic filtration should be coordinated
between the two countries.
5. Improved performance of new designs for electrostatic precipitators
should be verified.
6. Australian and U.S. low sulfur coal should be compared to
allow interpretation of Japanese results with collection of low-sulfur-
coal fly ash in the U.S.
-------
SUMMARIES OF JAPANESE TECHNOLOGY
Mitsubishi Heavy Industries Co., Ltd.
Takasago Technical Institute
2-1-1 Shinhama, Arai-Cho
Takasago, Hyogo Pref. 676 Japan
Personnel Contacted: N. Tachibana, Manage»
Y. Saito, Manager
K. Yata, Group Leader
K. Tashiro, Senior Engineer
Dr. M. Matsumoto
K. Tomimatsu
Mitsubishi Heavy Industries has research centers at Takasago,
Nagasaki, and Hiroshima. Air pollution control research at the latter
two deals with gaseous pollutants especially sulfur and nitrogen oxides.
Research at Takasago involves noise reduction as well as particulate
control for air and water. Particulate control research currently
stresses electrostatic collection but may give increased attention to
fabric filtration in the future. Mitsubishi personnel are concerned
with the projected large imports of Australian low sulfur coal for power
plant combustion. Consequently, filtration with acrylic bags at 120°C
is under consideration for fly ash collection. Recently completed or
active projects include:
1. Electric Coagulation - Pictures were taken at the inlet
and outlet of an electrostatic precipitator to determine
coagulation of hydrocarbon particles. At present most
electrostatic precipitators are used on heavy oil fired
power plants where resultant fly ash may form stable
agglomerates.
2. Acoustic Coagulation - The general phenomenon and the
Braxton device in particular were studied. Either as
a sole collector or as a conditioner for another device,
this approach was concluded to be less cost effective
than other approaches.
-------
3. Precipitator Electrode Spacing - For both cold- and
hot-side applications of electrostatic precipitators,
the optimum electrode spacing was determined. It was
generally concluded that a spacing from 400 to 500 mm
between collector electrodes was optimum in contrast to
U. S. precipitator designs where 200 to 300 mm is typical.
4. Electro Filter - For this concept, the particulate is
charged and collected in a high-void-fraction, deep-bed
filter. The method is very effective for collection
of high resistivity dusts but no satisfactory cleaning
method was found.
5. High Pressure Gas/Particulate Control - At 110 to 150°C and
2-3 kg/cm, the applicability of an electrostatic precipitator
was verified for blast furnace gas.
6. Vanishing Temperature - Experiments in hot-side precipitator
application were conducted to eliminate back corona by
increasing temperature for a variety of coal fly ash. As
temperature increases, resistivity decreases and eventually
back corona vanishes. (The U.S. delegation noted that
this method may not predict the vanishing temperature in
actual operation if residual fly ash on the collection
plates is deleted of charge carriers and becomes more resistant.)
7. New Types of Electrodes and Precipitators - Where space
charge is a problem, use of a newly developed electrode
with long spikes and a steep V-I curve was planned. Details
of the new precipitator type were not provided.
8. Development of Control for Coal Fired Boilers - Special
problems are expected in collecting fly ash from low sulfur
coal. Both hot-side precipitators and adapted cold-side
precipitators will be tested in a plant being constructed
to burn various types of coals.
-------
Nippon Steel Corporation
Nagoya Works
#3-5 Chome Tokai-City
Aichi Pref.
Japan
Personnel Contacted: A. Sakaguchi, Asst. Manager
Y. Kojima, Section Chief
Nippon Steel has a problem with high resistivity sinter participate
when using Chilean ore (a = 10 ohm-cm). Other ores from Australia and
South Africa do not present a serious problem (ft = 10 ohm-cm). To
deal with the worst case (when Chilean ore must be used), Nippon Steel
has installed a novel electrostatic precipitator with horizontal compartments
or "houses." Corona wires are horizontal, thin, stainless steel piano
wire (0.5 mm diameter). The wires as well as the plates are wrapped.
The spacing between grounded electrodes is extremely wide (1.2 m) and
the operating voltage is correspondingly high (140-150 kV), with a
maximum of 200 kV. The gas velocity is typical, 1.6 m/sec. The inlet
3
sinter particulate is at a concentration of 0.5 - 0.7 g/Nm and is
3
reduced at the outlet to 0.02 - 0.05 g/Nm . Cost of the precipitator in
1974 was 60,000 ¥/m3/min ($300/m3/nrin). Nippon Steel had calculated
that the cost of a standard precipitator would be lower but did not feel
that a conventional precipitator could handle their problem, especially
when they used Chilean ore. In addition to seven installations of the
novel house-type precipitator, Nippon Steel also has a precipitator with
a bias-controlled pulse charging system in combination with zig-zag
shaped electrodes. Experience with this system is limited: the anticipated
high resistivity problem for its application did not develop and the
charger is not operated in a pulse mode.
-------
Onoda Cement Company, Ltd.
Takara Plant
Toyohashi Pref. Japan
Personnel Contacted: t. Sugo, Maneger
M. Munakata
Onoda Cement Company has two installations which are of special
interest: A wide-space electrostatic precipitator in successful continuous
operation since 1972, and a hybrid (wet and dry) electrostatic precipitator.
Onoda Cement has three rotary kilns; however, only No. 2 was in production
at 1200-1250 tons/day. The wide-space precipitator is used on the
clinker cooler for No. 2 (see Figures 1 and 2). The precipitator has
two fields: the first with a plate-to-plate spacing of 320 mm and an
average voltage of 44 kV (65 kV maximum); and the second, a spacing of
570 mm and an average voltage of 80 kV (110 kV maximum). The inlet
loading to the precipitator is 4.3 g/Nm , and the outlet loading is
3
0.014 g/Nm with no visible plume. Other data are shown in Table 1.
The hybrid precipitator is used on the rotary kiln gas (see Figure 3).
The first field is dry and second is wet. Both fields provide approximately
96 percent collection efficiency. The collection plates in the second
field are washed continuously to a clarifying system which recycles
water to the precipitator. Onoda Cement uses water sprays to control
emissions from storage piles and conveyor belts.
-------
0:
IIMLETFROM
CLINKER COOLER
Figure 1. Wide plate spaced precipitator at Onoda Cement Company.
-------
NO VISIBLE
PLUME f
\
Figure 2. Stack and back side of Onoda electrostatic precipitator.
-------
Table 1. PARAMETERS OF ONODA PRECIPITATORS
Type
Number of fields
Discharge wire
Collecting electrode
Rapping (wires & plates)
Plate current, mA
Design voltage, kV
Gas flow rate, m /min
Temperature, °C
Gas velocity, m/sec
Inlet to field 1, g/Nm3
Outlet, g/Nm3
Efficiency, %
Year purchased
Cost, ¥
Wide Space
2
4 mm/SUS 27/star shaped
200 mm pitch
mounted on a frame
both fields, SS541
field 1, 7.3 x 3.0 m
field 2, 7.3 x 5.0 m
horizontal
400
field 1, 65
field 2, 110
2500
150
0.56
field 1, 4.3
field 2, - -
0.014
99.7
1972
68,500,000
Hybrid
2
4 mm/SUS 27/star shap<
200 mm pitch
mounted on a frame
SS41/9.0 x 5.5 m
STEN 3/9.0 x 2.5 m
horizontal
field 1, 600
field 2, 400
65
65
2090
150
0.66
20.5
0.8
0.03
99.84
1973
78,000,000
10
-------
HOLDING TANK FOR
PRECIPITATOR WASH WATER
Figure 3. Hybrid precipitator at Onoda Cement Company.
-------
Idemitsu Kosan Company, Ltd.
Chiba Refinery
Kaigan 2-1 Anesaki, Ichihara
Chiba, Japan
Personnel Contacted: K. Shiraishi, Manager
A. Iwasaki, Manager
K. Kimura
Y. Kikuchi
Chiba Refinery is using a novel electrostatic precipitator to
control emissions from a fluid catalytic cracker (FCC). When low sulfur
oil is treated in the FCC, resistivity at flue temperatures is greater
than 10 ohm-cm. To avoid this high resistivity, a precipitator with
cooled collection electrodes was installed. The collection electrode is
actually a series of 20 vertical rectangular water ducts. To clean the
collecting electrode, a scraper is lowered on a chain from a roller. The
scraping action reportedly works well, but some chain erosion has been
3
noted. Total gas flow rate is 214,000 Mm /hr. Inlet particulate loading
33
is 0.88 g/Nm , outlet 0.043 g/Nm . This precipitator also uses a wide
plate spacing (700 mm) and high voltages. There are three electrical
fields; voltages are 80-96, 70-84, and 63-75 kV, respectively. The
plate currents are 110, 65, and 60 mA, respectively. The system was
purchased in 1974 at a cost of ¥300,000,000. It was claimed that a
conventional electrostatic precipitator for this application would have
had to be twice as large: consequently this novel precipitator was 20-30
percent lower in cost. Further, the water heated in the precipitator is
used elsewhere in the plant for an energy savings which could pay out
the cost of the precipitator in a few years. The precipitator is pictured
in Figures 4 and 5.
12
-------
Figure 4. Cold electrode electrostatic precipitator at Idemitsu Kosan Company.
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PARTICULATE
COLLECTION
HOPPERS
COLD WATER
PIPING
Figure 5. Cold water piping and hoppers for Idemitsu precipitator.
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Kawasaki Steel Corporation
Chiba Works
1, Kawasaki-Cho Chiba City
Japan
Personnel Contacted: K. Tsutsumi, General Manager
H. Takao, Manager
T. Tanaka, Manager
K. Sakai, Sumitomo Heavy Industries
Kawasaki Steel Corporation is using several important new concepts
to prevent and control fugitive emissions associated with its Q-BOP
shop and the coke oven battery. Q-BOP direct emissions are controlled
by a venturi scrubber with a pressure drop of 30 in. H~0. Q-BOP fugitive
emissions are collected by a hooding system which is evacuated to a
3
reverse-air-cleaned baghouse rated at 18,000 m /min. The Q-BOP is
completely enclosed by the hooding system except for access, at which
time two doors slide away from each other to reveal the furnace. Emissions
produced while the doors are open are conveyed by natural draft to the
top of the Q-BOP shop (a distance of about 50 m) and through an electrostatic
precipitator on the roof (see Figure 6). This precipitator is constructed
of special light-weight, widely spaced plates to allow low overall
weight for roof installation. Collecting electrodes are made of electric-
conductive synthetic resin. The plate-to-plate spacing is 420 mm. The
3 3
inlet dust loading is 0.4 g/Nm ; outlet, 0.03 g/Nm ; and overall efficiency,
92.5 percent. Costs for this precipitator are comparable to those for a
conventional precipitator. Some expenses (such as those for structural
support and ducting) are less. However, the use of water washing to
clean the collecting electrodes adds an expense which balances out the
savings in support and ducting.
At the coke oven.battery, both charging and pushing operations are
hooded and evacuated through a control device. For charging, two circular
flue gas ducts are on either side of the charge car. These ducts have a
series of ports which may be accessed by the charge car hooding system
for any position of the charge car on the coke oven battery. When the
charge car moves to a new position, the connectors from the charge car
enter appropriate ports in the flue gas ducts. Charging emissions are
drawn from the charge car through the ducts to a wet scrubber.
15
-------
Q-BOP SHOP
BUILDING
Figure 6. Roof-mounted precipitator at Kawasaki's Chiba Works,
-------
For pushing, a movable hood (positioned above the car) catches the
push. The hood connects with a large rectangular duct that extends the
length of the coke oven battery. This duct also has a series of ports
which allow the hood to be connected at any position. The ports are on
top of the duct and are covered by metal disks which are raised magnetically
for access. When the pushing hood moves to a new position, the connector
from the hood covers three ports on the duct and the proper ports are
opened. Pushing emissions are drawn from the hood through the duct to a
wet electrostatic precipitator.
Other practices at Kawasaki Steel Corporation are worth noting.
Paved roads at the plant are washed down periodically during the day.
Trenches, dredged occasionally, on either side of the roads remove the
washed-off participate. This washing not only prevents fugitive dust
emissions from the roads but also provides an active method for reuse or
disposal of collected material. In large open areas where dust can
deposit, water sprays are used to control emissions. In other open
areas where it does not interfere with plant operation, trees and shrubs
are planted. Besides adding to the visual quality, such plantings
promote prevention and control of fugitive emissions.
17
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Kawasaki Steel Corporation
Chiba Works
1, Kawasaki-Cho Chiba City
Japan
Personnel Contacted: K. Tsutsumi, General Manager
T. Tanaka, Manager
H. Takao, Manager
K. Tahara, Engineer
Kawasaki began studying the application of high-gradient magnetic
filtration (HGMF) to steel mill waste waters in 1976. In coordination
with Sala Far Last (a division of Sala Magnetics of Cambridge, MA) and
Hitachi, Ltd., Kawasaki tested a pilot unit for 6 months on several
processes at their Chiba plant. Results were quite encouraging, and
Kawasaki decided to install a full-scale device to treat 900 m /hr of
scrubber waste water from a vacuum degasser (see Figure 7).
The production unit has been in operation for about a year (as of
May 1979). It was built by Hitachi under a Sala license. It has a 2.1
in diameter canister with a field capability of 0.52 tesla at 50 kW
input, but is normally operated at 0.3 tesla. Kawasaki estimates that
the system cost about 50 percent more than a competitive flocculation/filtration
treatment system. (See comments on cost in Hitachi visit description.)
The HGMF system also requires only 20 percent of the land area of a
conventional system.
Kawasaki is quite pleased with the HGMF installation. Its particulate
removal is good. The filter is backflushed about once an hour with high
velocity water. The only problem they have incurred is a gradual buildup
of residual material on the filter which necessitates external cleaning
every 6 months. They think this can be eliminated by replacing the
steel wool filter with wire cloth.
Kawasaki is considering installing HGMF systems to solve other
waste water problems, but have not yet studied any direct air applications.
18
-------
Figure 7. Magnetic filter at Kawasaki's Chiba Works
-------
Daido Steel Company, Ltd.
Machinery Division
1, Mutsuno-Cho, Atsuta-ku
Nagoya, Japan
Personnel contacted: I. Eguchi, Director
T. Adachi, Manager
J. Yano, Engineer
Daido produces specialty steels and forged and cast products for a
variety of industries. Among the activities of their Machinery Division
is the manufacture of high gradient magnetic filters (HGMFs). They have
tested the application of HGMF to:
1. Waste water from hot rolling mills.
I. Various other waste waters from steel mills, including
scrubber effluents from oxygen converters and vacuum
degassing systems.
3. Coolant in nuclear power plants.
4. Waste water from nuclear power plant.
5. Liquid sodium in fast breeder reactors.
6. Separation of iron from raw materials.
7. Other mineral processing.
8. Various other industrial waste waters.
Daido now has 10 pilot- and full-scale units operating in Japan. An
example is shown in Figures 8, 9, and 10. Most of these are in use in
the steel industry, processing BOF scrubber effluents, vacuum degassing
waters, and rolling mill waste waters. The largest is a 1.5 m diameter
3
unit that filters 1000 m /hr of rolling mill effluent. This unit operates
at 0.3 tesla and reduces the suspended solids of the effluent from 150
to 25 ppm. They backflush with a combination of water and compressed
air. The oil content of the waste water is less than 30 ppm and presents
no problems to filter backflushing. Table 2 gives results of Daido's
analysis of the potential for applying HGMF to various steel mill waste
waters.
20
-------
TANKS FOR REVERSE
FLOW CLEANING
MAGNET
Figure 8. Magnetic filtration system at Daido Steel Company
-------
OUTLET
TANKS FOR
CLEANING
ro
MAGNET
Figure 9. Close-up of Dai do Steel magnetic filter.
-------
ro
CO
Figure 10. Power supply for Daido Steel magnetic filter.
-------
Table 2. COMPARISON BETWEEN HGMF AND OTHER METHODS OF FILTRATION
Classification
Kind of waste water
Influent suspended solids, ppm
Desired effluent suspended
solids, ppm 2
Influent volume, m /h
Method of filtration
Flow rate, m/h
Filter run, h
Time of back wash, min
Voluwe of back wash water,
m /day
Power consumption of magnet
at 0.3T, kW 2
Space requirement, m
Running cost relative to
other methods
Installation cost relative to
other methods
Class 1
(ferromagnetic fraction of
suspended solids,>60%)
From the scrubber for an
oxygen converter
150
below 15
HGMF
200
1/2
1
16
5
4.5
0.7
1.1
20
Sand Filter
30
8
15
30
—
8
1
1
Class 2
(ferromagnetic fraction of
suspended sol ids ,^30%)
From a hot rolling mill
150
below 15
HGMF
600
1/3
2
340
'30
40
0.4
0.4
1100
Clarifier-
sand filter
system
40
24
15
300
—
500
1
1
Class 3
(ferromagnetic fraction of
suspended solids, 5-10%)
Cooling water of the
steam ejector in vacuum
degassing installation
80
below 25
720
HGMF
200
1
4
270
40
200
0.3
1.5
Clarifier
2
continuous
none
none
—
700
1
1
-------
Dai do has conducted feasibility studies on the application of H6MF
to gas cleanup. Their preliminary conclusions are that HGMF, although
not economically competitive under most conditions, might be competitive
when the waste gas is hotter than 300°C or when space is limited. They
alluded to some experimental work with sinter dust but revealed no test
data to support these preliminary conclusions.
Dai do designs its own magnets and has them made by a Japanese
transformer manufacturer. They claim that their price for magnets is
about half that of U.S. competitors exporting to Japan. One significant
design difference is that they don't use hollow conductors in the coils,
like U.S. manufacturers do. Instead Daido mounts copper fins between
the insulated magnet coils and conducts the heat out to water-cooled
tubes that are wrapped around the outside of the magnet coils. They
claim that this design is much less expensive. They also use different
grades of wire cloth (instead of steel wool) for a filter matrix. All
of their systems operate cyclically.
25
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Hitachi Research Laboratory
Hitachi, Ltd.
1-1 Saiwai-Cho, 3-Chome,
Hitachi-shi, Ibaraki-ken, 317
Japan
Personnel Contacted: Y. Oguri, Deputy General Manager
H. Yamada, Senior Engineer
K. Ootsuka, Senior Researcher
A. Hino, Engineer
T. Misaka, Researcher
Hitachie built and installed Kawasaki Steel's high-gradient magnetic
filter (HGMF) unit at a cost of approximately $1 million using components
imported from the U. S. Since then they have produced a similar unit
for Nippon Steel at about half the cost, using Japanese components and
the experience they gained from their first installation. They see a
very bright outlook for the application of HGMF to waste water cleanup
in Japan, but have not yet studied gas applications. Table 3 gives
Hitachi's analysis of optimum operating conditions for steel mill waste
water application.
26
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Table 3. SUMMARY OF APPLICATION OF HGMF FOR STEEL MILL WASTE
ro
Hot Rolling Mill
(scale pit overflow)
Continuous Casting
(scale pit overflow)
Vacuum Degassing
Influent suspended solids
a)
b)
c)
Optimum
a)
b)
c)
d).
Concentration, mg/n
Elemental components
Fe, %
Mn, %
Size distribution, m
operations conditions
Flow velocity, m/hr
Magnetic flux density, tesla
Feed time, min/cycle
Duty cycle, %
100 - 150
60
—
20 - 100
500
0.3 - 0.5
60
95
150 - 200
50
0.2
40 - 150
700
0.1
60
95
80 - 100
5-10
20 - 30
5-20
150 - 250
0.5
60
95
Effluent suspended solids
a) Concentration, mg/£
20
20 - 25
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University of Tokyo
Masuda Laboratory
Department of Electrical Engineering
7-3-1, Hongo, Bunkyo-ku
Tokyo 113, Japan
Personnel Contacted: Dr. Senichi Masuda, Professor
Y. Nonogaki, Graduate Student
H. Nakatani, Graduate Student
M. Washizu, Graduate Student
Prior to visiting Japan, EPA had developed a- list of questions for
the developer of the Aut-Ainer, Eikosha Company, Ltd. These were submitted
to Masuda to allow ample time for Eikosha to respond. There was also a
general discussion of the Aut-Ainer with Masuda.
The initial discussion of the Aut-Ainer was followed by an information
exchange: reviews of current research projects in Masuda's department
and several EPA projects.
Masuda is continuing work with a three-electrode system involving
pulsed power supplies (Boxer, Charger). He uses a biased DC supply with
a superimposed 1.5 kHz oscillation to provide corona. This maintains a
reasonably high electric field with a controlled current density to
prevent the development of reverse ionization (back corona).
Masuda is also continuing work to identify the various modes of
reverse ionization and conditions required for the initiation of back
corona.
The research activities are a continuation of those listed in the
EPA report, "Electrostatic Precipitator Technology Assessment: Visits
in Japan, November 1977," EPA-600/7-78-110 (NTIS No. PB 298389), June 1978.
28
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Eikosha Company, Ltd.
No. 2-8, 1-Chome
Shiba Daimon
Minato-Ku, Tokyo
Japan
Personnel Contacted: K. Aoi, Chairman
T. Aoi, Managing Director
Dr. 0. Hirao, Consultant
M. Ando
K. Kita
K. Aoi and other Eikosha personnel reviewed the development of the
Aut-Ainer automotive particulate control device. They reviewed its
development. They then responded to questions that EPA had presented to
them earlier.
The Aut-Ainer is approximately the size of an automotive muffler.
It consists of expansion chambers followed by collection regions filled
with metal wool. It is cooled by outside air flowing through a central
pipe to contribute to condensation.
Twenty-six questions were answered: the first 9 from EPA's Andrew W. Kaupert
(Ann Arbor, MI); the next 17 from Southern Research Institute and EPA's
Particulate Technology Branch (IERL-RTP).
Question 1: What data does the developer have, displaying particulate
data under transient conditions?
Response: The Aut-Ainer has been tested under transient conditions
but only on gasoline engines. These tests were conducted by Nisson Motors
in road and chassis dynamometer tests. The car used was a Nisson Model
P-510 with a regular leaded gasoline engine (Model 8D-252) at idling
speed: 10 degrees B.T.D.C./600 rpm and CO = 3.5 percent. Collection
efficiency was determined by weighing the Aut-Ainer and a five-stage
absolute filter. The driving cycle consisted of an acceleration to lap
speed (chosen between 50 and 105 km/hr) and two decelerations—accelerations
between lap speed and 30 km/hr and the final deceleration to stop.
Several designs of the Aut-Ainer were tested: in general all provided
70 percent collection efficiency for the tests which lasted as long as
nearly 7,000 km.
29
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Question 2. Does any particulate data exist using the proposed
particulate test procedure for LDV?
Response: All data available is as described in the response to
Question 1.
Question 3. What transient procedure was used to develop
transient particulate data, if any?
Response: As already noted, no transient procedure has been used
to test the performance on a diesel engine. The driving cycle (called
"A" DURATION MODE) was used in the leaded gasoline engine tests.
Question 4. Is the concept amenable to heavy-duty engine
applications?
Response: There are no apparent limitations which would restrict
application of this concept to light duty vehicles. The developer feels
strongly that it can be applied to heavy duty engines and is designing a
unit for an 11-ton truck.
Question 5; What have the developers done to improve the
short period of time between cleanings?
Response: The developer feels that the most recent design can go
6,000 km between cleanings and expects that this can be increased to
10,000 km. Most early designs allowed for collection only within a
single muffler sized unit which would fill up in 1,000 - 2,000 km. The
latest design does not utilize ultimate collection within this single
unit but instead diverts some of the exhaust gas and most of the particles
to a secondary collection chamber. The system then consists of the
primary collection chamber, a diversion device at the end of the primary
collector, and a secondary collector. The primary collector is a three-
stage throttle plate and packing design which has been tested in many
different configurations.
The simplest configuration (disk throttle plates inside a cylindrical
collector body) seems to work as well as any and is the configuration of
30
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choice. The diversion devices tested are a cyclone and a screen with
reverse air blowback. The concept is that particles collected in the
primary collector will be agglomerated. As the agglomerates grow, they
will break off from the collection packing and approach the diversion
device. Since these are large agglomerates, they are easily diverted by
a cyclone or caught on a screen. If they are on the screen, they are
cleaned off and blown to the secondary collector by a rotating reverse
air jet. In either case/agglomerates leaving the primary collector are
diverted to the secondary collector. The secondary collector used by
the developer was a fiber glass bag inside a drum. This provided a
large storage volume and could be made larger on a large truck. However,
for a light duty vehicle where space is very limited, the secondary
collector should be redesigned. The secondary collector may be made
small if it is to be designed for extremely easy emptying. Possibilities
are a. hopper (which dumps) or a bin (which may be removed or replaced in
one motion). Hence, this concept is not to increase the distance between
cleaning but rather to increase the ease of cleaning.
Question 6: Can a device be made available for testing at EPA,
Ann Arbor, on any of the vehicles mentioned in the
January 4th memo?
Response: A device'can be made available and the price is from
$1,250 to $2,500 depending on the type. Prices quoted are for hand
manufactured items and do not reflect mass production costs. In order
to supply a device, the developer must know the gas flow rate, muffler
size, and exhaust pipe diameter.
Question 7: What are the developer's future plans for this concept?
Response: The developer claims to have already spent $7 million on
independent experimentation and testing. Consequently, the developer is
hoping to work in the future more closely with a potential user of the
technology. The form of the work would be determined by the user's
needs.
31
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Question 8: What is the approximate cost of the device and are
any critical or scarce materials necessary for
fabrication?
Response: The developer estimates actual production costs at
¥5,000 ($25) for a production rate of 10,000 per month. The sale price
might be as high as ¥20,000 ($100). Primary construction material is
18-8 stainless steel. No critical or scarce materials are necessary for
fabrication.
Question 9: Of all the different constructions and cleaning
arrangements proposed in your paper, what is the
preferred or most effective method of collection?
Response: The preferred arrangement is as described in the Question
5 response: a muffler-sized device, which is the primary collector,
followed by a cyclone and a secondary collection device. The secondary
collector can be optimized either to provide large extra storage of
collected particulate or to provide ease of particulate removal from the
vehicle as stored.
(NOTE: The above questions were submitted by
EPA's Andrew W. Kaupert (Ann Arbor, MI). The
following questions were developed by EPA's
Particulate Technology Branch (IERL-RTP) and
Southern Research Institute.)
Question 10: What is the practicality of methods to divert the
previously collected material to a collection
device?
Response: The fabric filter or cyclone collection method can be
used more effectively if either an auxiliary pump or pressure restriction
is added in the outlet circuit.
Question 11: What is the frequency of expansion hole plugging in
the device?
Response: There is no evidence of plugging.
32
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Question 12. What is the approximate back pressure of the device?
Response: About 12 inches W.C. under heavy load.
Question 13. What data are available about the degradation in
performance with miles of operation?
Response: Mitsubishi is expected to develop this data. In general,
degradation in performance appears with a back pressure of about 0.25
atmospheres.
Question 14. What is the expected lifetime of the device?
Response: Similar to that of an automotive muffler.
Question 15. What is the approximate size of the device?
Response: Comparable to a muffler.
Question 16. What data are available on the collection efficiency
for hydrocarbons?
Response: No quantitative data are available.
Question 17. Are sample analyses available for particulates,
liquids, and gases for both new and high mileage
conditions?
Response: Samples can be made available. Gas analyses will be
made in Japan. Liquid and particulate samples can be shipped to U.S.
Question 18. What is the surface area to volume of the collection
media?
Response: The material exhibits a porosity of about 97 percent.
33
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Question 19. Does the manufacturer think that all the condensation
occurs in the expansion chamber?
Response: No data are available other than temperature. Measurements
indicate that significant cooling occurs across the perforated plates.
Question 20. How does fuel economy compare with and without the
Aut-Ainer operating at a collection efficiency of
about 70 percent?
Response: The manufacturer thinks there is no difference in fuel
consumption.
Question 21. Has the Aut-Ainer efficiency been checked as a function
of temperature?
Response: Efficiency was stated to be higher at low temperatures;
that is, of course, consistent with condensation.
Question 22. Has the filter material packing density been varied?
Response: It has changed over a small range but no definitive
study has been performed.
Question 23. What information is available on collection efficiency
as a function of particle size?
Response: None, Mitsubishi will attempt to obtain some data.
Question 24. What data are available on the chemical composition
of materials for both the inlet and outlet?
Response: No data for diesel applications.
Question 25. What collection temperature was used for the samples
from the gasoline application?
Response: The samples were collected at near ambient temperatures.
34
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Question 26. What additional information is available on the
system that recirculates the collected material
through the engine?
Response: This system was used only on the gasoline engine. A
truck and automobile, both equipped with diesel engines, were road-
tested on a drive from Tokyo to Harone. The major test, on a 2-1/2 ton
truck, started with a clean Aut-Ainer using three stages of packing and
a reverse air cleaned backup screen. It was stopped for inspection
after about 60 km. The device had collected quite a bit of material on
the filter but only a small amount in the fabric filter in a bypass line
(see Figures 11-13). However, the fundamental collection seemed to be
functioning. After the inspection, the Aut-Ainer was bypassed and
visual observation of the exhaust emissions could be compared with and
without operation. Although there was no remarkable change in the
exhaust appearance, a change was visually detectable.
35
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SECONDARY COLLECTOR STORAGE
u
BACK COVER
Figure 11. Opening Aut-Ainer after road test.
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Figure 12. Removing internals from Aut-Ainer collector.
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CO
CO
THROTTLE PLATES
Figure 13. Throttle plates and mesh packing.
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Mitsubishi Motors Corporation
No. 2 Technical Center
2-1-1 Shinhama, Arai-Cho
Takasago, Hyogo Pref. 676
Japan
Personnel Contacted: K. Yamada, General Manager
Y. Ishii, General Manager
M. Kametani, Manager
T. Hirano, Manager
Y. Aizawa, Chief Engineer
At Mitsubishi Motor Company's test laboratories in Tokyo, tests of
an Aut-Ainer had just started operating on a heavy-duty diesel engine
mounted on an engine dynamometer (see Figures 14-16). This particulate
device was similar to that installed on a diesel truck except that it
was equipped with a cyclone collector instead of a screen collector to
divert a side stream. The Aut-Ainer being tested was a three-stage,
throttle plate and packing design with a cyclone at the end to divert
agglomerated particles and a side stream of exhaust gas to a filter.
The source of particles was half the output from a Mitsubishi V-8, Model
8DC8A (direct irijection) with a displacement of 14,806 cc. The engine
was run on an engine dynamometer at engine speeds of 1000 and 2200 rpm
and loads of 91.3 - 101.6 kg-m. Collection efficiency was measured with
a Bosch smoke density meter. Greatest emissions were at low speed, high
load for a reading of 5.5 which was reduced to 2.9 by the Aut-Ainer.
Using a correlation between smoke number and concentration supplied by
Mitsubishi, collection efficiencies were generally around 50 percent.
Volume of gas treated was 112 to 249 cfm and the pressure drop ranged
from 9 to 35 mm Hg.
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+.
c
INLET SMOKE METER
AUT-AINER
OUTLET SMOKE METER
Figure 14. Experimental setup at Mitsubishi Motors.
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SMOKE METER
COOLING AIR JACKET
Figure 15. Close-up of Aut-Ainer.
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SECONDARY COLLECTOR
OUTLET
PRIMARY COLLECTOR
PO
INLET
Figure 16. View of primary and secondary collectors.
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Japan Automobile Research Institute, Inc.
Yatabe-Cho, Tsukuba-Gim
Ibaraki-Ken, 300-21
Japan
Personnel Contacted: T. Kohno, Director
K. Goto, Director
Z. Konishi, Manager
H. Hari, Manager
Dr. Y. Kim, Research Supervisor
M. Nakamura, Psychologist
Japan Automotive Research Institute (JARI), an independent non-
profit automotive research center, provided information on a number of
research programs. Of particular interest was a study of burning alcohol
in a diesel engine. In the engine, equipped with dual injectors, diesel
fuel was injected first. Alcohol was injected after ignition. JARI
claims that up to 75 percent of the energy can be supplied from alcohol
in an engine with a compression ratio of 20:1.
JARI is initiating studies in which rats are exposed to a variety
of automotive emissions. Both behavioral and biological effects are
being investigated. JARI hopes to expand the studies to include bacteria.
43
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TECHNICAL REPORT DATA
(Please read Inunctions on the reverse before completing)
1. REPORT NO.
EPA-600/8-79-031a
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Particulate Control Highlights: Recent Developments
in Japan
5. REPORT DATE
November 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
D.C.Drehmel, C.H.Gooding (RTI), and
G.B.Nichols (SoRI)
8. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAME AND ADDRESS
This is an IERL-RTP (see Block 12) inhouse report.
Efforts of coauthors Gooding and Nichols were funded
under EPA contracts 68-02-3142 (Research Triangle
Institute) and 68-02-2610 (Southern Research Institute).
10. PROGRAM ELEMENT NO.
EHE624A
11. CONTRACT/GRANT NO.
N.A.
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Inhouse; 5-7/79
14. SPONSORING AGENCY CODE
EPA/600/13
is. SUPPLEMENTARY NOTES IERL-RTP Author Drehmel's Mail Drop is 61- his phone is 919/
541-2925.Related reports include EPA-600/8-77-020a through -020c, and EPA-600/
8-78-005a through -005d.
16. ABSTRACT
repOrt; describes results of visits to Japan to assess research and
development of new particulate control technology, and to evaluate the applicability
of the Aut-Ainer particulate control device to diesel engines. New technology obser-
ved includes hooding systems for coke oven charging and pushing, fugitive emissions
control in aQ-BOP furnace building, novel electrostatic precipitators (ESPs), mag-
netic separators, and hybrid control devices. Fugitive emissions are well controlled
in two iron and steel plants visited. Fugitive emissions are prevented by road wa-
tering and process hooding. Fugitives in a large building are collected by a special
lightweight ESP. Novel ESPs utilize approaches such as wide plate spacing, advanced
charging systems, and water cooled collection electrodes. Magnetic separators are
currently used for water pollution control and are under consideration for air pol-
lution control. The Aut-Ainer device has evolved from an experimental approach to
the device development stage over several years. The device currently has limited
applicability to particulate control from diesel engines; however, its basic collection
characteristics seem to be based on sound principles. With limited additional devel-
opment in the general area of removing the previously collected material, the
device appears promising.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
C.
COSATI Field/Gioup
I3B
Pollution
Dust
Diesel Engines
Iron and Steel
Industry
Coking
Leakage
Electrostatic Pre-
cipitators
Electromagnetism
Wetting
Pollution Control
Stationary Sources
Japan
Particulate
Aut-Ainer Device
Fugitive Emissions
Q-BOP
11G
21G
11F
13H
14B
131
20C
3. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
48
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
44
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