VDI-RICHTLDSHEN
August I960
VEREIN
DEUTSCHER
INGENIEURE
Gasauswurfbegrenzung
Schwefeldioxyd
Kokereien und Gaswerke
Koksofen (Abgase)
VDI 2110
RESTRICTING EMISSION OF SULPHUR DIOXIDE
FROM COKE OVENS AND GAS PLANTS
This publication, translated from the German, was prepared by i
the Anthracite-Mining Association, Essen. All rights reserved.
Reproduced with permission by the
U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
Washington, D. C.
VDI-Kommission Reinhaltung der Luft
VDI-Handbuch Reinhaltung der Luft
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Foreword
This is one of several dozen VDI Clean Air Committee specifications
on air purification which the Division of Air Pollution of the U.S. Public
Health Service has obtained permission to translate, publish, and distri-
bute in limited quantity. A complete list of the VDI publications being
published by the Division of Air Pollution appears on the inside back
cover. Because the VDI Committee from time to time revises these
specifications, this and other publications in the series may be super-
seded by later publications.
The VDI Clean Air Committee specifications are compiled by trade
or professional associations and published by the Committee. The Com-
mittee has neither official status nor regulatory authority, although West
German governmental agencies participate in its activities. Air quality
specifications published by the Committee are therefore advisory, rather
than regulatory. They may however later be adopted by West German
governmental authorities.
The English translations were done by the Joint Publications Research
Service of the Office of Technical Services, U.S. Department of Commerce.
It should be borne in mind that various terms literally taken from the Ger-
man do not have the same connotation in English? for example, the Word
"standard" frequently appears where the word "criteria" might better
reflect the comparable American meaning, since in this country "standard"
is generally meant to imply a legally enforceable value, while "criteria"
usually means a recommended value upon which standards may be based.
The publication and distribution of these translations by the Public
Health Service constitutes neither endorsement of the specifications nor
of the air quality or emission limitations recommended in them* We
believe that they contain much useful information that would otherwise
not be available to non-readers of German and for this reason have made
them available to workers in the air pollution field in the United States.
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RESTRICTING EMISSION OF SULPHUR DIOXIDE
FROM COKE OVENS AND GAS PLANTS
Prepared tys
The Anthracite-Mining Association, Essen.
VDI No. 2110, August I960
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TABLE OF CONTENTS
Page
VDI Committee for Air Purification iv
Introduction 1
1. Technology 2
1.1 Firing of Coke Ovens 2
1.2 Type, Composition and Calorific Value of Underfeed
Gases 3
1.21 Coke-Oven Gas 3
1.22 Producer Gas 1*
1.23 Blast-Furnace Gas ..... 6
1.2lj Methane Gas 6
1.25 Recirculated Coke-Oven Gas 7
1.26 Other Underfeed Gases 7
1.3 Guide Values for Sulphur-Dioxide Emission 8
2. Reduction of Emission and Low-Layer Concentration
of Sulphur Dioxide 10
2.1 Reduction of Sulphur-Dioxide Emission . 10
2.11 Reduction of Sulphur-Dioxide Content of Coke-Oven Gas . 11
2.12 Utilization of Sulphur-Free Underfeed Gases 11
2.2 Reduction of Low-Layer Sulphur-Dioxide Concentration
by Stack Design 13
3. Guide Lines for the Restriction of Sulphur-
Dioxide Emission .. ......... 13
- ii -
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Table of Contents (continued)
Page
3»1 Restriction of Emission on the Basis of Immission ... 13
3o2 Restriction of Emission by Technical Measures . , , , , 13
- iii -
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VDI COMMITTEE FOR AIR PURIFICATION
The VDI Committee for Air Purification is composed of experts in
all fields of importance for air purification. These experts collaborate
with the Committee on their own responsibility and without compensation
and are proposed for the Committee by the following societies and insti-
tutions :
German Society for Hygiene and Microbiology
German Society for Oil and Coal Chemistry
German Society of Gas and Water Experts
German Meteorological Services
Society of German Chemists
Society of German Iron Mine and Steel Mill Experts
Association of Anthracite Mines
Technical Inspection Associations
Society of German Steel Mill Experts
Society of German Foundry Experts
VDI Trade Section on Dust Technology
Association of Steam Boiler Owners
Scientists from Universities and Institutes in Biology, Chemistry,
Pores-try and Agriculture, Human and Veterinary Medicine, Metal-
lurgy, Physics and Technology
Research Institute of the Cement Industry
Federation of German Industry (Chemical Industry, Oil Industry,
Automobile Industry, etc.)
German Federal Railroads
Federation of German Farmers
Federation of Community Associations
Settlement Federation of the Ruhr-Coal District
Competent Federal and State Ministries
Institute for Water, Soil and Air Hygiene of the Federal Public
Health Service
Public Inspection Services
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INTRODUCTION
The VDI Specifications on Air Purification are divided into the
following groups?
1» Permissible Immission Concentration (PIC-values)
2<> Calculation of the Distribution of Dust and Gas
3o Restriction of the Emission of Dust and Gas
ho Dust and Gas Measuring Techniques,,
In the evaluation of problems of air pollution, the inner rela-
tion of these four groups of specifications must be considered,
The committee for Chsraotechnieal Investigations on control of
quality and operation (Chemists Committee) in the Anthracite-Mining
Association has assumed t!ie task,, upon instigation of the VDI Committee
for Air Purification, to investigate the air pollution caused by coke
and gas plantse
In coke and gas plants3 dust, tar mist and gas are emitted
during several production stages 0 The present VDI Specifications con-
cern the emission of sulphur dioxide wi*h the waste gases created by
the firing of the coke ovens0 The essential points treated herein
are the types composition and calorific value of the different under-
feed gases as well as guide values for sulphur-dioxide emission!
measures for reduction of emission and low~layer concentration of
sulphur dioxidej and guide lines for the restriction of sulphur-
dioxide emission,
Special VDI Specifications are published on the restriction
of emission of sulphur dioxide with the waste gases of coal~constituent
processing plants,,
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1. Technology
1.1 Firing of Coke Ovens; ;
Coal is converted to coke at about 1,000° C in closed chambers.
A modern coke oven (horizontal-chamber oven) consists in principle
of an upper section with the oven chambers and a lower section with the
heat exchangers.
Each oven chamber is outlined by two chamber walls, a bed
and a ceiling vith doors at both ends. The chamber walls of
two adjacent oven chambers form a so-called heating wall which is
divided by headers into a great number of combustion flues. Combus-
tion of gas in the flues creates the heat required for coking.
The heat exchangers may be constructed according to the re-
generation principle generally employed today, or according to the re-
cuperation principle. Consequently, we distinguish between regenera-
tion and recuperation ovens. Ovens without heat exchangers are
designated as waste-heat ovens and are now built only infrequently.
Coke ovens may be heated by gas with a high calorific value,
so-called rich gases (coke-oven gas, methane gas, recirculated gas,
natural gas and other hydrocarbons) or gases with low calorific value,
so-called lean gases (producer gas, blast-furnace gas). Coke ovens
heated only by rich gas are called rich-gas ovens. Ovens heated
alternately with rich or with lean gas are called compound coke-ovens.
In gas plants, ovens are frequently heated only with producer gas.
Regeneration ovens are alternating-flue ovens in which a number
of the flues draws combustion flames for a period of 20 to 30 minutes
and the other flues carry off the waste gases during this period. The
procedure is reversed during the subsequent period. Upon leaving the
non-heated flues, the waste gases are passed through heat accumulators
(regenerators) and here transmit a part of their still available
sensible heat to the lattice of the regenerator to be heated (heating
period). Subsequently, air and/or air and lean gas are sent through
the heated lattice (separately in the latter case) and pre-heated
- 2 -
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(cooling period). Two regenerator chambers (regenerator half), filled
with lattice work, therefore belong to each heating wall. In rich-
gas ovens, no preheating of the gas is provided because the high tem-
peratures would produce cracking of the hydrocarbons with consequent
disadvantages. From the heat accumulators, the waste gases enter the
waste-gas flues at a temperature of 200-300°C and subsequently the
stack. In general, one waste-gas duct is arranged along each of the
longitudinal sides of the coke-oven battery.
Recuperation ovens have single-direction draft in which the
heat of the waste gases is transmitted by dividing walls continuously
to the air and/or air and lean gas to be preheated,, Such ovens are
no longer used in coke plants. However, medium and small gas works
are generally operated with recuperation ovens which are heated with
producer gas from built-in gas generators. This eliminates preheating
of the producer gas because this enters the combustion chambers immedi-
ately upon leaving the generator. This recuperation system is employed
in ovens which have smaller dimensions in comparison to coke ovens of
standard design. In place of exclusive producer-gas firing, such ovens
are frequently fired additionally with purified municiple gas.
In waste-heat coke ovens, firing is effected only with coke-
oven gas. The latter and the combustion air enter the combustion flues
also without preheating. The waste gases leave the ovens at a high
temperature and enter the so-called waste-heat boiler installation in
which the sensible heat is utilized to about 3!?0OC.
The waste gases of the ovens described are discharged into the at-
mosphere through one or more stacks, depending on the output of the in-
stallation, and create the required draft.
1.2 Type, Composition and Calorific Value of Underfeed Gases
Gas;
A part of the coke-oven gas produced in the coking of coal is
normally utilized for underfeed firing of the coke ovens and the excess
is supplied to other consumers. The composition of the coke-oven gas
depends on the type of coal and operating conditions,,
Depending on the sulphur content of the coal and the operation
of the installations for coal-constituent processing, the coke-oven
gas reaches the underfeed firing system with a greater or lesser content
of hydrogen sulphide. By employing modern processes, it is possible
under certain circumstances to lower the hydrogen-sulphide content in
large coke plants (partial desulphuration) .
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Table 1
GUIDE VALUES FOR NON-PURIFIED COKE-OVEN GAS
I
Components
Carbon dioxide
Heavy hydrocarbons
Oxygen
Carbon monoxide
Hydrogen
Methane
Nitrogen
Sulphurous Admixtures
Hydrogen sulphide
Carbon disulphide
Carbon oxysulphide
Total Heat
Combustion heat
N Calorific value
Formula
COg
CnKm
°2
GO
H2
CHU
N2
Formula
K2S
03 n
COS
Sytibol
HO
HU
^-vol
1.5-2.5
1.5-3.5
0.2-0.8
5-8
50-60
22-30
14-10
gAm^***
5-13*
1.5-5**
O.ii-1.2
0,1-0.2
kcal/fam^
1^,600-5,300
14,100-1,700
•»• Without partial desulptruratiori
*» With partial desulphuration
1.22 Producer Gas;
The volume of producer gas -utilized for the firing of coke ovens
depends on the quantitative requirements of the consumers of coke-oven
gas which fluctuate in time and" are moreover dependent on the economic
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situation. The combustion characteristics of producer gas make it
necessary to construct coke ovens as cerapound furnaces. Producer gas
is manufactured from small-grain coke grades (primarily crushed coke
III and IV) and sometimes with an admixture of coke fines<>
During gasification, the greater part of the sulphur in the
coke passes as hydrogen sulphide into the producer gas. The calorific
value of producer gas is only about 2.3$ of coke oven gas. The firing
of coke ovens therefore necessitates four times the amount of producer
gas as compared to coke-oven gas and this has been taken into considera-
tion in the guide lines for sulphur-dio:;clde emission in Section 1,3.
Table 2
GUIDE VALUES FOR PRODUCER GAS
Components
Carbon dioxide
Carbon monoxide
Hydrogen
i
Methane
Nitrogen
•
Sulphurous Admixtures
Hydrogen sulphide
Sulphur dioxide
Total Keat
Combustion heat-
Calorific value
Formula
cc2
CO
H£
Formula
-,:: . 3
sc.
Symbol
'•'o
r
*-vol
3-5
25-30
10-13
0-0.2
50-55
gAm3
1-2
traces
kcalAm3
1,100-1,200
1,050-1,150
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1.23 Blast-Furnace Gas;
The gas created in blast furnaces is utilized to a large extent
in these installations themselves and also by the auxiliary installa-
tions of the ironworks. The excess is used either for the firing of
coke ovens or is supplied in compound operation to adjacent mine
coking plants. Like producer gas, blast-furnace gas is employed for
firing compound coke ovens and contains only traces of sulphurous
admixtures (Table 3).
Table 3
GUIDE VALUES FOR BLAST-FURNACE GAS
Components
Carbon dioxide
Carbon monoxide
Hydrogen
Methane
Nitrogen
Sulphurous Admixtures
Total Heat
Combustion heat
Calorific value
Formula
C02
CO
H2
CHU
N2
-
Symbol
Ho
Hu
Jg-vol
8-16
25-32
0.5-1*
0-0.3
52-60
traces
kcal/tom3
850-1,100
830-1,070
1.2li Methane Gas;
In a number of mines, methane is drawn off for reasons of opera-
tional safety and for economic considerations. Because composition and
calorific value of the gas may vary greatly, methane from mines is
generally burned combined with producer or coke-oven gas for the firing
of coke ovens. Methane contains no sulphurous admixtures.
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Table 1*
GUIDE VALUES FOR METHANE FROM MINES
Components
Methane
Oxygen
Nitrogen
Sulphurous Admixtures
Total Heat
Combustion heat-
Calorific value
Formula
CHs,
°2
N2
"
Symbol
H
Q
\
#-vol
1*0-70
8-12
32-50
none
kcal/Wm-3
3,800-6,700
3,1*00-6,000
1,25 Recireulated Coke°0ven Gas s
Some coking plants furnish coke-oven gas to adjoining chemical
plants (nitrogen synthesis) -which decompose the gas, subsequent to de-
sulphur ation, for the production of hydrogen for ammonia synthesis by
undercooling0 The residual gas Is 'at-illged as so-called recirculated
coke-oven gas by the supplier for the firing of coke ovens and is free
of sulph-orous admixtures,
1,26 Other ffrderfeed gases a
liquid gases and/or gasoline hswe also been suggested for the
firing of coke ovens. Their utilization presupposes a carrier gas that
can be carsyareted- •wd.th these fuels 0 Carrier gases may be coke-oven or
producer gas^ waste gases from coke GTens or air,, The utilization of
liquified gases and/or gasoline is dependent on a number of technical
and economic prerequisites, In general,'the processes are still in the
experimental stage. Only two mine coking plants utilize liquified gas
and/or gasolene in continuous operation for the firing of coke ovens,
In the first case, coke oven gas is mixed with carbureted air as under-
feed gas. In the second ease, coke-oven waste gases are carbureted with
gasoline. Both liquified gas and gasoline are practically free of
sulphur.
7
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Table 5
GUIDE VALUES FOR RECIRCUIATED COKE-OVEN GAS
Components
Carbon dioxide
Heavy hydrocarbons
Oxygen
Carbon monoxide
Hydrogen
Methane
Nitrogen
Sulphurous Admixtures
Total Heat
Combustion heat :
Calorific value
Formula
coe
CnPrn
I
°2
CO
H2
CHJ,
N2
-
Symbol
Ho
HU
g-vol
0.3-0.8
0.6-0.8
0.8-1.3
1^-18
7-10
U8-56
19-2li
none
kcal/Nm^"
5,500-6,100
5,100-5,500
1.3 Guide Values for Sulphur-Dioxide Emission;
In the combustion of underfeed gas, sulphurous admixtures are
converted to sulphur dioxide which is discharged into the atmosphere through
the stack together with the waste gases of the coke-oven battery.
The emission of sulphur dioxide depends on the volume of under-
feed gas and its content of sulphur compounds. Guide values on the
specific consumption of underfeed gas and the emission of sulphur
dioxide per ton of coking coal are contained in Table 6.
For the calculation of the consumption of underfeed gas, heat
requirements per kg for coking coal (10$ water) are assumed as 530
kcal when firing with coke-oven gas, and as 550 kcal when firing with
other underfeed gases.
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Table 6
GUIDE VALUES FOR S02 EMISSION PER 1 TON OF COKING COAL
Type of Gag
Coke-oven gas
1. w/o part.
desulph.
2. with part.
desulph.
y
Producer gas
Blast-furnace gas
Methane
.:?.cc:i.rov.!Isted gas
Calorific
Value
kcal/%n3
li,200
ii,200
1,300
830-1,070
3,1*00-6,000
5,100-5,500
Gas
per ton
Nm3
130
»
130
500
670-520
160-90
110-100
Content
of Gas
a) hydrogen
sulphide
b) organic
sulphur
gAm3
t
a) 5.0-13.0
b) 0.5-1.3
a) 1.5-5
b) 0.2-0,6
a) 1.0-2.0
b) 0
traces
0
0
so2
per ton
kg
1.3-3.5
O.U-1.3
0.9-1.9
traces
0
0
The calorific value (H, ) of the coke-even gas varies in general
between k, 100 and It,700 kcal/§ra3. If we calculate with a calorific
value of ii,20Q kcal/Nm^ about 130 Nm3 of coke oven gas are required
per ton of moist coking coal.
The calorific value of producer gas differs only little from the
mean value of 1,100 kcal/ftm^,, On the basis of this value, about 500 Nm3-
of producer gas are required for the coking of 1 ton of moist coking
coal.
Indications on the range of variation of the calorific value of ,,.
blast-furnace gas, methane from mines and recirculated coke-oven gas
as well as on the underfeed requirements are contained in Table 6.
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When firing coke ovens with these gases, there is practically no
emission of sulphur dioxide,,
The following indications of the total sulphur dioxide emis-
sion of the mine coking plants of the Ruhr area is based on the operat-
ing conditions of the year 1956 in which 60 coking plants with a total
consumption.of $Q,h million tons of coking coal (10$ water) were in
operation,, For the firing of the coke-oven batteries, the following
volumes of gas were required;
It, 836 million NTT. 3 of coke-oven gasj
2,272 million Nm3 of producer gasj
a,370 million Nm3 of blast-furnace gasj
1)35 million Nm-' methane and recirculated gas.
The emission of sulphur dioxide for each coking plant was cal-
culated from the volume of underfeed gases consumed and their- content
of sulphur dioxide 0 In 1956., the total emission of sulphur dioxide
by the mine coking plants amounted to £3,000 tons.
2o Reduction of Emission and Low-Layer
Concentration of Sulphur Dioxide
2»1 .Reduction of Sulphur-Pi oxide Emission;
The sulphur content of coking coal is dependent on the type and
processing of the coal extracted in the individual mines. During
processing? so much of the mineral admixtures is removed that the ash
content of the coke produced amounts to only about 10$. After processing,
coking coal contains a total of 0.9-1»6$ of sulphur, primarily in
organic form, so that a further reduction of the sulphur content by
processing techniques is not possible,
During coking, up to 30$ of the total sulphur remains in the
coke-oven gas (cf. Table 1 for sulphurous admixtures). The emission
of sulphur dioxide with the waste gases of the coke ovens is dependent
on the content of the underfeed gases in sulphurous admixtures and on
the volume of the gas conditioned by its calorific value. When under-
feed firing coke-oven batteries with non-desulphurated coke-oven gas,
the sulphur-dioxide emission reaches a maximum value corresponding to
the content of sulphur compounds of the respective gas. Such emission
can be reduced by the following measures?
a) Partial desulphuration of coke-oven gas (cf. Section 2.11);
b) Firing of coke ovens with sulphur-free underfeed gases
(cf. Section 2,12).
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2.11 Reduction of Sulphur-Dioxide Content of Coke-Oven Gas;
When extracting ammonia from coke-oven gas by the indirect re-
covery process, acid constituents (hydrogen sulphide, carbon dioxide,
etc.) are partially removed by solution and by bonding to the ammonia.
In gang scrubbers, only about 20| of the hydrogen sulphide in
coke oven gas is absorbed by the washing fluid during practically
complete extraction of the ammonia. This share is insufficient for
an economic utilization of the hydrogen sulphide. The latter is there-
fore returned into the raw gas or added to the underfeed gas.
Greater selectivity in the removal of hydrogen sulphide can
be achieved through shorter contact periods of the gas with the washing
fluid. Since hydrogen sulphide is absorbed more quickly by the wash
fluid than carbon dioxide, short contact periods therefore produce
greater efficiency in the removal of hydrogen sulphide. During long
contact periods, e.g., in gang scrubbers, hydrogen sulphide in the
vashing fluid, is recovered by absorption with carbon dioxide and
added to the coke-oven gas.
In order to obtain short contact periods, special types of
scrubbers, e.g., bell-type wash-towers or spray washers, are utilized.
More than 50$ of the hydrogen sulphide is removed from the cbke-oven gases by the
scrubbers. The consequent enriching of the washing fluid with hydrogen
sulphide makes it possible to utilize it for the production of sul-
phuric acid and/or sulphur.
A further reduction of the hydrogsn sulphide content of the coke-
oven gas is accomplished by increased extraction through special processes,
e.g., ammonia recirculation, potassium process. This increases extrac-
tion of hydrogen sulphide to 80$ and more.
Partial desulphuration installations of this type existed in
1956 already in 19 mine coking plants of the Ruhr area. The sulphur-
dioxide emission of about 53,000 tons in 1956, indicated in Section 1.3,
would have amounted to about 76,000 tons without such installations.
When firing coke ovens with producer gas which contains only
1-2 g of the hydrogen sulphide per Nm33 an economically justifiable
reduction of the sulphur content and the consequent sulphur dioxide
emission is not possible.
2.12 Utilization of Sulphur-Free Underfeed Gases;
In 1956, a number of mine coking plants of the Ruhr area utilized,
in addition to coke-oven gas and producer gas, underfeed gases practically-
free of sulphur for the firing of coke ovens. The available volume of
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blast-furnace gas,, methane from mines and recirculated coke-oven gas
is limited for various reasons so that a replacement of the sulphur-
containing underfeed gases is possible only to a limited extent,,
Blast-furnace gas was used in 1956 partially as underfeed gas by
9 mine coking plants'! the volume available for this purpose depends
on the production of pig iron arid the consumption in their own and
related installations of the iron works„ The utilization of blast-
furnace gas for underfeed firing presupposes the existence of compound
furnaces. Because of its low calorific value,, blast-furnace gas can
be transported economically only ever short distances„ The utilization
of blast-furnace gas is dependent on the seasonally and economically
given demands for the coke-oven gas to be replaced„
At the ironworks coking plants, the coke ovens are generally
fired by blast-furnace gas and no sulphur dioxide is emitted in this
case. If insufficient amounts of blast-fumaee gas are available due
to operational failures or shutdown of blast furnacess the fuel re-
quirements are covered partially by coke-oven gas which is also used
for firing coke ovens if there is no other possibility for utilizing
this gas.
Firedamp was used in 1956 for the firing of coke ovens at 5
mine coking plants. The available amount was small and depends on the
geological and operational conditions of the individual mines.
Recirculated coke-oven gas ^as utilised in 1956 at 6 mine
coking plants'. Utilization of this gas presupposes compound operation
between coking plants and chemical plants (e.g^ ammonia synthesis).
The available amount is dependent on the volume of coke-oven gas required
by the chemical plant and from the method of processing of the gas.
If the coke-oven batteries of these 20 mines had used exclusively
non-desulphurated coke-oven gas instead of the practically sulphur-free
xmderfeed gasess sulphur dioxide emission in 1956 would have amounted
to 88,,000 tons.
The concentration of sulphur dioxide in the waste gases of the
coke ovensj at the top of the stack5 is dependent on the composition
of the underfeed gas, the excess volume of combustion air and the content
of the underfeed gas in sulphur "Containing compounds„
For example,, in the combination of coke-oven gas with a combustion
heat of 5j030 kcal/Mm^, the theoretical rsq-udrement of combustion air is
li.6l Nm3 per Nm3 of coke-oven gas0 During combustion with an excess
air volume of 20$,, 6025 Nm.3 of waste gas per Nm3 of underfeed gas are
produced. On the supposition that the fuel is a. non-desulphurated coke-
oven gas with 8 g of hydrogen sulphide and 0,5 of other sulphur-containing
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compounds per cubic meter of gas, the waste gas contains 205h g of
sulphur dioxide per cubic meter. If this gas is previously partially
desulphurated to a content of 2 g of hydrogen sulphide and 0.5 g of
othejf sulphur-containing compounds per m3 of gas? the sulphur-dioxide
concentration in the waste gas is reducea,-fy? 0,74 g/m3. If other
sulphur-poor and/or sulphur-free gases are used as fuel in the coking
plant or if the ovens are fired exclusively with such gases, the
sulphur-dioxide of the waste gas becomes jfurther reduced,
2,2 Reduction of Low-layer Sulphur-Dioxide Concentration by
Stack Designs
At a given emission of sulphur dioxide, the low-layer concentra-
tion (disregarding meteorological conditions) is determined by stack
height as well as the temperature and velocity of the waste gases at
the top of the stack.
In addition to discharging the waste gases into the open air,
the stack has the task of drawing the volume of combustion air
required for the combustion of the underfeed gases through the combus-
tion chamber,, The diameter of the stack depends on the number and
volume of the coke ovens as well as on the composition of the under-
feed gases. The height of the stack is primarily determined by the
amount of draft required for the maximum coal charge of a battery,
In the mine-coking plants of the Ruhr area, this height is an average
of 67 m.
The stack height conditioned by the operation of the ovens in
the coking plants is adequate for maintaining the permissible low-layer
concentration of sulphur dioxide in most cases,
3. Guide Lines for the Restriction of Sulphur-Dioxide Emission
The following conditions should be taken into consideration in
designing net* coking plants,
3,1 Restriction of Emission on the Basis of Immissions
In the vicinity of coke and gas plants, the content of hydrogen
sulphide of the air in layers close to the ground should not exceed the
^Permissible Smmission Concentration (PIC) for sulphur dioxide estab-
lished in VDI Specifications No, 2108 (in preparation). In its calcula-
tion, any existing sulphur-dioxide load from other emitters should be
taken into consideration,
3«2 Restriction of Emission by Technical Measures g
In addition to the points disc-osaed in Section 3,1» all measures
possible under the present status.of technology should be taken which
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will produce a reduction of sulphur-dioxide emission. In particular,
partial desulphuration of coke-oven gas, utilized for fueling coke
ovens, should be provided in newly designed coking plants.
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VDI CLEAN AIR COMMITTEE SPECIFICATIONS, PUBLISHED IN ENGLISH
BY THE DIVISION OF AIR POLLUTION, U.S. PUBLIC HEALTH SERVICE
VDI No.
Title
2090 Sources of Air-Polluting Substances
2091 Restricting Dust Emission From Forced-Draft Boiler Installations,
Capacity 10 Ton/Hr and Over, Hard-Coal Fired with Mechanical
Grates
2092 Restricting Dust Emission From Forced-Draft Boiler Installations,
Capacity 30 Ton/Hr and Over, Hard Coal-Dust Fired with Dry Ash
Removal
2093 Restricting Dust Emission From Forced-Draft Boiler Installations,
Capacity 30-600 Ton/Hr and Over, Hard Coal-Dust Fired with liq-
uid Ash Removal
2094 Dust Prevention - Cement Industry
2095 Dust Emission From Induced-Draft Ore-Sintering Installations
2098 Restricting Dust Emission From Natural-Draft Steam Generators,
Capacity 25 Ton/Hr and Less, Lignite-Fired with Stationary or
Mechanical Grates
2099 Restricting Dust Emission in Blast-Furnace Operation
2101 Restricting Dust Emission From Copper-Ore Smelters
2102 Restricting Emission of Dust From Copper-Scrap Smelters
2103 The Restriction of Chlorine Gas Emission
2104 Terminology in Air Purification
2106 Permissible Immission Concentrations of Chlorine Gas
2107 Permissible Immission Concentrations of Hydrogen Sulphide
2108 Permissible Immission Concentrations of Sulfur Dioxide
2109 Restricting Emission of Hydrogen Sulphide and Other Sulphur-Con-
taining Compounds, Except Sulphur Dioxide, From Gas Generators
in Coke, Gas, and Coal-Constituent Processing Plants
2110 Restricting Emission of Sulphur Dioxide From Coke Ovens and Gas
Plants
2115 Restricting Emission of Dust From Manually Operated Central-
Heating Boilers, Capacity 600, 000 KCAL/Hr and Less, Fired with
Solid Fuels
2281 Restricting the Emission of Fumes From Diesel-Engine Vapors
2284 Restricting Emission of Dust and Sulphur Dioxide in Zinc Smelters
2285 Restricting Dust and Sulphur-Dioxide Emission From Lead Smelters
2290 Restricting Emission From Gas Generators in Coke and Gas Plants
2292 Restriction of Dust Emission in Anthracite-Briquet Factories
2293 Restricting Emission of Dust in Anthracite Processing Installations
2302 Restricting Emission of Dust, Tar Mist and Gas when Charging Coke
Ovens
2105 Permissible Concentrations of Nitrous Gases
GPO 669-179
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