LRTAP-1-75.pdf (2.184Mb)

EMP - 1/75

PRELIMINARY REPORT ON

EXISTING KNOWLEDGE WITH REGARD TO S0

₂

EMISSION SOURCES

BY

B FJELD AND B OTTAR

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NORWEGIAN INSTITUTE FOR AIR RESEARCH P.O. Box 115, 2007 KJELLER

NORWAY

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This report was first presented at the

meeting of the Working Party on Air Pollution Problems in ECE, 13-17th January 1975. The OECD reports "Oil Statistics, Supply and Disposal"

and "Statistics of Energy" for 1973 have now been published and new calculations have been performed, based on the consumption figures for 1973.

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There are still some discrepancies between the emissions calculctLecl hure, and the emissions given in the LRTAP emission survey. Table 7 illustrates this.

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For some countries, the emissions from industrial processes (not included in the survey based on

energy statistics) may explain this, but not in all cases. In order to obtain comments from each country as to the reason for these discrepancies, we now send this report to each of the OECD-member

country participating in the LRTAP-project.

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PRELIMINARY RE PORT ON EXISTING KNOWLEDGE WITH RE GARD TO S0

2 EMISSION SOURCES

PRE FACE

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At the last meeting of the Senior Advisers Group, ECE, it was decid~d to work out a European emission survey for sulphur dioxide. As a first step it was agreed that a scientist to be appointed by the USSR together with Dr. B Ottar, Norway, as representatives of respectively the Eastern and Western European countries, should work out a report based on available information on this subject. In July 1974, Dr. J Brodsky was appointed by the USSR, and the first meeting took place in Moscow on 20-22 November 1974. At this meeting, it was agreed that a first report should be presented at the meeting of the Working Party on Air Pollution on 13-17 January, 1975.

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In the present report, first the need for an emission survey and its possible applications are briefly pointed out. In a second chapter, available data for the total energy consumption and total emissions· of sulphur dioxide in the countries are presented for various types of

sources, and finally a list is given of the literature on which the report is based.

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The emission of sulphur dioxide has been calculated in two ways. In Lh e first calculation, the OECD statistics of fuel consumption and emission factors estimated in an earlier OECD report (1) have been used to estimate the emissions for 1973. The second and more correct set of emission data also applies to 1973 and was worked out by the countries for the OECD project "Long Range Transport of Air Pollutants ¹¹ (LRTAP) ( 2) .

The two sets of data are not directly comparable. The LR'TAP emission survey also includes emission from chemical processes.

For some countries, the difference is, however, much larger thu.n this. It is believed that the LRTAP data are the more correct ones because these data were collected by the countries fo~ an emission survey, while the other set of data for 1973 are based on simple energy statistics. These discrepancies may become less when the countries h~ve had an opportunity to adjust the primary data.

l INTRODUCTION .

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The present r-e por-t represents a f .i.r st step in the construe-- tien of a European emission survey for sulphur dioxide, for use in connection with a coopePative programme for monitor-

·ing and evaluation of the long range transmission of air pollutants in Europe. The main objective of this pPogramme, which was recently discussed at a meeting in Oslo 3-5

December 1974, is ~o provide information on the quantity and . significance of the large scale geographical dispersion and

deposition of air pollutants in Europej in order' to enable evaluations of specific air pollution problems and trends in Europe.

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At present the selection of effective solutions to the manage- ment of the air pollution problem is limited by lack of suffi- cient information on the emissions of pollutants from various sources, their long range transmission and effect. Infor-

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u.ac ion on i:he re lat i ve importance of local and distant sources would assist governments in developing national abatement

st~ategi.es, and promote international cooperation in this field.

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It is generally recognized that the first problem requiring further investigation on a large geographical scale would be the aci.dification of the precipit~tion and other effects arising from the long rangc transmission of sulphur com- pounds, primarily due to the emission of sulphur dioxide from antropogenic so~rces~

Monitoring and evaluation of the long range dispersion and deposition of sulphur dioxide requires that observed con- centrations arid deposition data can be compared with esti- mated vctlucs calculated from atmospheric dispersion models, using an appropriate emission survey. Experience shows that

J n o r-de r- to be ,1hle to a c co urrt for the influence of change s in wind direction, atmospheric stability, etc, this requires the use of atmospheric dispersion models based on 6-hourJy evaluations of the weather parameters in a grid system of 100-150 kilometer grid length. Data from the WMO network are satisf~ctory fori this purpose. The time and space re- solution of oth~r data used in the calculallu11, j .e. the observed air concentrations and the emission data, must be selected to fit in with this requirement.

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In order to limit the observational effort, concentration data observed as 24 hour averages and with a space resolution of about 250 kilometers may be sufficient) provided some con- sideration is given to geographical and topographical

featufes. For the emission survey a grid distance of about half the grid distance used for the atmospheric dispersion model, should be used, as this will improve the representa- .tivity of the model calculation appreciably without adding

much work to the collection of the emission data.

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For the emission of sulphur dioxide a space resolution of

½

^{0. · 1atitude} x 1

°

longitude ( 55 X: 55 krn² at 60°N) will be

suitable. From a practical point of view this coordinate system is easily identifiable, and the fact th~t the size of the grid element bccom6s a func·tion of the latitude, is of little consequence, as this grid system is easily trans- formed into any oth~r system by the use of suitable computer pi-iog:r'armne s ..

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In this survey the emissions have to be split 1n·a constant and a time variable part. Also a disiinction should be made between sources with effective chimney height above and below 100 m, for use in two-layRr atmospheric dispersion models.

the diurnal variation of the emissions is important if asso- ciated with signiticant diurnal varialions of the vertic~l dispersion. Day to day variations (weekends, etc), and seasonal variations, are particularly impqrtant and should be included.

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At pr~sent, severctl dispersion models are available and these can be ope~ated on the basis of an emission survey of the type described and available data from the WMO network. These include statistical models based on trajectory calculations, as well as budget-type mod e ls ( Eulerian 'and Lagr-ang i an ) , which. dI'e

based on numerical solutions of the continuity equation.

The two types are used to evaluate the transport and de- position of air pollutants, statistically and on a day to day basis.

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Once established, a proven dispersion model has many appli- cations. The statistical trajectory analysis may be used·to evaluate tl1e amounts deposited in a given area and where they come from. T.he budget-type models can be used to cal- culate the contribution from selected source areas to other parts of the region in a given weather situation. The models can be used to forecast concentration levels and the distri- bution of pollutants in the atmosphere 1-2 days in advance .

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By altering the emission data, the effects of improved abate- ment or·a further increase of the emissions of sulphur

dioxide may be studied. Thus, the effect of·assumed trends in.energy consumptj_on and development on the concentration of the air pollutants may be studied.

Finally, it should be pointed.out that an emission survey of the type described here, is constructed for large scale dis- persion c a Lcu La't i.on s only. As t.he resolution r-c qu i r ed in ·the concentration field is of the order 100-200 kilometer, various

·approximation methods can be used t~ estimate the emissions from the grid elements with sufficient accuracy.

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2 DESCRIPTION OF SULPHUR DIOXIDE EMISSION SOURCES FROM THE POLLUTION POINT OF VIEW

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. In this first survey it was agreed to give figures tor the total· emission of sulphur dioxide in each country for the

f o Ll.ow.ing ma i.n categories of sources:

A) Heat and power stations, including cases when power production is com- bined with heating purposes.

B) Industrial emission data including industrial heating and specified on major industrial categories .

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C) Heating of houses including offices and regional heating plants if these do not at the same time produce

electricity.

For each of these catigories the total consumption of the various types· of fuels (coal, heavy oil, Li.ght oil etc) is given together with t·heir emission factors. These emission factors give the percent sulphur emitted per ton oil equi-

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valent (T.o.e.). In this way it is taken into account that

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a part of the sulphur in the fuel is retained in the ash of .s c Lå.d fuels. For fuel oils the emission factor is c qua I to

the sulphur content.

By multiplying the consumption fizures and the emissi.on fac-

·tors together a first e st i.mat e _f oe t:he ern i.s s i.ons of sulphur dioxide can be obtained. However, a mo~e detailed emission survey has be~n constructed for the OECD-countries in con- nection with the OECD-project ¹¹Lonr.; Rnnr;e Transport of /\i.r Pollutants". This survey also .i nc Lude s the emissions of S0₂ from industrial processes.

The type of industrial branches for which the data are given may differ from one country to anoth~r, depending on the data available.

Much of the data given in this report were collected in con- nection with the two OECD-1Jrojectc "Study on /\ir PolluHon from Fuel. Cornbu s t i.on .i.n Stationary So ur-c e s " (1) and "Long

Ra ng e 'I'r-a n s po r-L

or

^{A.ir Po I Lu t} arrt s " (LRTJI.P) (2).

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For most·of the countries in Western Europe reference (1) gives the consumption of fuels in 1968 for the following groups: "Power Stations", "Re f i.ner-Le s:! , ¹.1 Iron and Steel _ Works '¹, n Coking plants and Gasworks ¹¹, u Other Industries ¹¹

and "Dome s t i.c and Commercial hee t i.ng!". Some of the countries did not give consumption figures for the different indu- strial branches. In these cases total figu~es for the in- dustry have been given under 't he title ¹¹ Other Industry¹¹•

In table 1 a survey of the consumption of gas, oil and coal for the mentioned grdups of users is given for 1968. The designation "coaJ.¹¹ covers all types of solid fuel, and by

11 fuel o i.L" is meant all types of fuel oil. All the f .i.gur-e s have been converted to T.o.e.

Table 2 Blvcs the emission factors for all.the. fuels used in 1958. These factors were provided by the different countries (1) and give the percentage of sulphur emitted

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per t.o.e. that is burnt. Minor changes in these factors may have taken place during the later years. This has, however, not been taken into account.In cases where the emission factors were not given, values have been estimated.

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Consumption figures for 1973 are given in table 3 and table 4.

Data for the consumption of fuel oils are taken from the annual OECD report "Oil Statistics - Supply and Disposal"

(3). Reference (3) did not give the consumption by the refineries, these figures are taken from the OECD report

"Statistics of Energy'' (4). Reference (4) also gives the consumption of gas and solid fuel for the different groups of consumers. The emissions calculated from the fuel

consumption are also given in table 3 3nd 4.

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A comparison between the figures given in table 1 and those given in table 3 and 4 indicatP.s how the consumption pattern has changed from 1968 to 1973. The consumption of gas has

increased consioerably, and in most cases at the expense of the coal consumption. This particularly applies to the

countriei situated around the North Sea, because of the findings of gas and oil in the region.

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As rnenLioned, an emission survey has been constructed for the .OECD countries, giving the emissions in a grid system with

individual grid areas of \⁰ latitude times 1° longitude. This survey is to a great extent based on detailed studies carried out by the countries themselves. For countries that did not give information, the emissions were estimated by the use of population statistics, information on the economic and indus- trial structure and other data available .

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ln table 5, values from this survey are given for the emissions from the different qroups of consumers within P.rlr.h country.

Some of the countries gave the emissions for the groups

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mentioned, while others gave the slightly different split up.

For these countties only the totals are given in table 5.

Reference (2) also gives the emissions separated in a

continuous and a variable part (the variable part includes

,71 l seasonal heating) , arid t.h o corresponding emission per inhabitant was calculated for each square in the different countries. In table 6, these emission factors are given together with the total emissions for each country.

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In table 7, the values given in table 5 are compared with emissions of sulphur dioxide calculated from the figures given in table~ 2, 3 and 4. Considerable differences will be noticed. One reason for this is that the data in table 5

include emissions of sulphur dioxide direttly from the industrial processes.

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For several countries, these factors alone can not explain the differences. Generally, the LRTAP emission survey (2) is believed to be the more accurate, as these data were

collected by the countries for the purpose of constructing an emission survey. The calculated emission data in this document are based on emission factors estimated for 1968

and statistics of energy consumption for 1973. All consumption figures for solid fuels were given in metric tons. In conver- ting those values to tons of oil equivalents, the conversion factors given in "World Energy Supplies ¹¹(5) were applied.

It is uncertain whether the conversion from metric tons to oil equivalents is in accordance with the emission factors used. This.will have to be controlled by each country.

As no emission Lac t.o rs Lo r gct~ lrave Le eri provlded by the countries, a factor of 59 kg/Teal has been used in ~11 calculations. This may be wrong in some cases. However,

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a different emission factor for gas will hardly change the overall picture.

If these problems should have been studied in detail, much more time would have been required to complete the present report. Also, it is felt that these problems are more easily dealt with by each country in question.

In a Concawe report (6) from November 1974, the limits on sulphur contents of fuel oils are given for most of the countries in Western Europe. For some countries, the values seem to be a little higher than the emission factors given in table 2. New calculations have not been performed, but the differences are not likely to change the overall picture.

In the following, some comments u.re given to the background material used for each of the countries.

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AUSTRIA

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Austria did not take part in the "Study on Air Pollution from Fuel Combustion in Stationary Sources" (1). The figures in table 1 are taken from the OECD report·"statistics of Energy" (7). A comparison between table 1, 3 and 4 shows that from 1968 to 1973, the consumption of gas doubled,

while the oil consumption increased by 60 %. The consumption of solid fuels decreased by 30 % during the same period.

The emissions given in table 5 are given by Austria.

BELGIUM

The consumption figures for 1968were given in tons. In this report, these values are converted to t.o.e .. From 1968 to 1973, the consumption of gas almost doubled, while the coal consumption decreased by 10 %. The oil consumption increased by 15 ~- ~he emissions given in tables Sand bare estimates.

DENMARK

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For Denmark, the 1968 consumption figures and emission fQctors were given on a t.o.e. basis. All the industrial consumption was gi ven in one group: ¹¹ oche r ind us Lries ¹¹• The tables 1 - 4

show no significant increase in the gas consumption, but the consumption of fuel oil has increased by 40 %, while the coal consumption of fuel oil has decreased by 45 %. The emission data for "Power Stations", "Industry" and "Domestic and Commercial Heating" were provided by Denmark.

FINLAND

Consumption figures for 1968 were not available in reference (1}. The figures in table 1 were taken from the OECD-report "Statistics of Energy" (7). A

definite increase in the comsumption of oil has taken

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place between 1968 and 1973 (approximately 60%), while minor changes appear in the consumption of gas and coal.

Emissions for the LRTAP emission survey were orovided by Finland.

FRANCE

The consumption figures and emission factors for 1968 were given in tons and have been converted to t.o.e. basis. From 1968 to 1973, the consumption of coal has been reduced to 50 % of the 1968 level. The consumption of gas and fuel oil has almost doubled during the same period.

Emission figures for the LRTAP emission survey were provided and distributed by France on the groups given in table 5. The emission from the refineries may seem high, but this also includes emissions from the Lacq district.

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GERMANY

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All consumption figures and emission factors were given on a t.o.e. basis. The consumption of fuel oil doubled during the period 1968/1973, while the gas consumption increased with 37 %. The coal consumption remained almost constant.

For the LRTAP emission survey, the emissions from house- heating, power stations and industry have been provided by Germany .

GREECE

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· All the consumption figures and the emission factors for 1968 were given on a t.o.e. basis. The figures for 1973 show that 65 % of the consumption of fuel oil is heavy fuel oil, and the consumption of liquid fuels doubled from 1968 to 1973. The emission data are estimates.

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The consumption figures and emission factors for 1968 were given on a t.o.e. basis. For 1973, only total consumption figures were available. The emission data are estimates.

ITALY

The consumption figures for 1968 were tctken from the OECD Energy Statistics (7). From 1968 to 1973 both the oil

consumption and Lh e IJctS cu11s ump t i.on have increased by 60 % •

The emission data were estimates.

LUXEMBOURG

All consurnplion figures and emission factors for 1968 were given on a t.o.e. basis. The emission data are estimatRs.

THE NETHERLANDS

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The consumption figures and emission factors for 1968 were given on a t.o.e. basis. The consumption figures for 1973 show a definite change in the consumption pattern. The consumption of gas has increased by more than 300 %, while the coal consumption has been reduced to 1/3 of the 1968 level. 'fhe oil consumption has decreased by 20 % • In 19 7 3, 60 % of the energy consumption was covered by natural gas (8) and after 1972, the consumption of coal is expected to be insignificant•

The emissions given in table 5 were provided by the Nether- lands.

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NORWAY

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The consumption figures and emission factors for 1968 were given on a t.o.e. basis. A comparison between table 1 and table 3 and 5 indicates no particular changes in the

consumption pattern. The oil consumption increased by 30 %.

The emission data were provided by Norway.

'PORTUGAL

1\.11 consumption figures u.nd emission factors for 1968 were given on a t.o.e. basis. The consumption of oil increased

by 300 % from 1968 to 1973, while there was no definite change in the consumption of gas and coal. The emission data are

estimates.

SPAIN

A.11 consumption figures and emission factors for 1968 were given on a t.o.e. basis. Table 3 shows that the consumption

of fuel oil more than doubled from 1968 to 1973 .. A definite increase in the coal consumption has also taken place. The emission data are estimates.

SWEDEN

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The consumption figures for 1968 were taken from Swede~s national report (9). No definit changes in the consumption

pattern have taken place from 1968 to 1973. The oil consumption increased with 27 %. The emission data given in table 5 were provided by Sweden.

SWITZERLAND

Consumption figures and emission factors for 1968 were given on a t.o.e. basis. From 1968 to 1973, the consumption of oil has increased by 45 %. The coal consumption is decreasing.

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The emission data for the LRTAP emission survey were provided by Switzerland.

UN I'rED KINGDOM

The consumption figures for 1968 were taken from the national report from the United Kingdom (10).

From 1968 to 1973, the coal consumption has decreased by 20 %, while the gas consumption has increased by 70 %. The consump-

tion of oil has increased with 30 % during the same period.

From 1972, the increase in energy consumption is expected to he covered by the increased use of gas. The emission data

given in table 5 were provided by the United Kingdom.

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LITERATURE

(1) Air Management Sector Group. Survey on Regional Sulphur Dioxide Emission.

NR/ENV/72.44 (Final Revision), Paris, June 22, 1973.

( 2) Rys tad, B, Strr'.lmsøe, S, Amble, E, Knudsen, T:

The LRTAP Emission Survey.

LRTAP - 2/74, November 1974.

(3) 1973 Oil Statistics - Supply and Disposal.

Annual OECD-report compiled by the Oil Committee, Paris 1975.

(4) Statistics of Energy 1959-1973.

OF.CD, ruris 1975.

(5) World Energy Supplies 1969-1972, Statistical Papers, Series 7, No 17, United Nations, _New York, 1974 .

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(6) Existing Environmental Regulations of concern to the OiJ Industry in Western Europe.

Report No 7/74, Stichting Concawe, The Hague, November 1974.

(7) Statistics of Energy 1954-1908, OECD, Paris 1970.

(8) The Control of Air Pollution by Sulphur Dioxide in the Netherlands.

J. Suurland and A. Houweling.

(9) Joint Group on Air Pollution from Fuel Combustion in Stationary Sources.

National Report: Sweden

PAC/70.4/18, Paris, June 1971. ·

(10) Joint Group on Air Pollution from Fuel Combustion in Stationary Sources.

National Report: United Kingdom PAC/70.4/17, Paris, September 1971.

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