Testing of the methodology for the estimation of the

wastewater generation in the sector industry

Statistical Office of Estonia

Environment and Sustainable Development Statistics Section

Background

• The Eurostat/OECD Joint Questionnaire on the State of Environment, part Water asks data for wastewater generation and loads of pollutants (BOD, suspended solids, N-tot, P-tot) in discharged wastewater by economic categories.

• Up to present there was no data available on the wastewater generation by the sector industry.

Tasks

• Find the wastewater volume and loads by selected industries by NACE codes

• Testing of existing methods for estimating wastewater volumes and pollutant loads

Sources1. Report and database of Estonian Environment

Information center “Water management”

2. Survey of Statistical Office “Water management”

3. Database of wastewater treatment plants

4. M.Zessner, S.Lindtner "A method for load estimations of municipal point source pollution"

Statistical Office additional survey

Survey population All industrial enterprises which have not produced environmental report but have produced the PRODCOM statistical report were surveyed related to water management

AIMS

Reach the full coverage of industrial sector on NACE 2digit level on water use (by purpose types) and wastewater generation

Figure out the quantity relationship between the water use and wastewater generation on NACE 2 digit level

NACE Number of enetrprises Reports presented

Not filled questionnaires Not active

15 138 112 20 6 17 50 38 10 2

177 22 18 3 1 18 187 132 48 7 19 32 26 6 0 20 262 182 71 9 21 14 13 1 0

221 67 31 30 6 222 47 31 15 1 23 2 0 2 0 24 22 19 3 0 25 52 43 8 1 26 49 43 6 0 27 4 3 1 0 28 167 132 34 1 29 64 53 9 2 30 6 2 3 1 31 29 20 9 0 32 26 19 6 1 33 21 12 8 1 34 10 9 1 0 35 17 10 7 0

361 95 76 17 2 362 17 11 5 1

total 1400 1035 323 42

Survey population of Statistical Office survey

Enterprises were handled in two categories:

THE REAL DATA ON WASTEWATER GENRATION WERE USED for the enterprises who presented data on water use and wastewater generation

THE DATA WERE ESTIMATED ON THE BASES OF NET SALES for the enterprises who did not present data on water use and wastewater generation

Wasteater factor:

Amount of generated wastewater, m3 _____________

Net sales, kronos

NACE factor

m3/kroon

waste water amounts

estimated

15 0,177 17 723 17 0,029 8 052

177 0,280 11 996 18 0,070 1 758 19 0,087 14 164 20 0,034 101 21 0,027 9 868

221 0,018 103 427 222 0,070 0

24 1,141 68 646 25 0,027 1 877 26 0,083 2 388 27 0,054 1 376 28 0,092 24 287 29 0,081 9 762 30 0,005 450 31 0,041 12 742 32 0,092 6 769 33 0,138 12 446 34 0,033 235 35 0,064 3 140 36 0,107 17 968

Estimation of the missing

data in Statistical Office

survey

Principles for the estimation of generated wastewaterquantities by economic activities (NACE group)

Statistical Office survey results

Estimationsof wastewaterquantities on the bases ofEEIC database on water use

Estimationsfor missing wastewaterquantities based on monetary factor

Wastewater

quantities

For each economic

activity group:

wastewater quantities by

types

NACE category Waste water total genartion

Industrial use (incl cooling water) Everyday use

15 6 368 299 5 410 620 957 679 17 2 265 730 1 090 942 1 174 788 18 492 578 193 872 298 706 19 105 620 5 971 99 649 20 1 321 994 346 237 975 757 21 8 053 218 4 117 729 3 935 489

221 18 064 998 17 066 222 155 254 127 134 28 120 23 529 500 529 500 0 24 3 871 310 3 536 853 334 457 25 52 200 7 914 44 286 26 1 050 510 405 809 644 700 27 8 468 2 685 5 783 28 265 352 171 708 93 644 29 143 567 41 868 101 699 30 1 109 0 1 109 31 41 879 8 903 32 976 32 112 827 59 848 52 980 33 134 636 116 065 18 571 34 33 977 18 837 15 140 35 82 126 8 789 73 337 36 516 057 225 200 290 857

21 724 935 13 476 993 8 247 941

Total wastewater generated

...as the sums of the three enterprise categories data

0 1 000 000 2 000 000 3 000 000 4 000 000 5 000 000 6 000 000 7 000 000 8 000 000 9 000 000

15

17

18

19

20

21

221

222

23

24

25

26

27

28

29

30

31

32

33

34

35

36

itk

HINNANG

stat vaatlus

“Waste water generated” as the sum of the discharges of three enterprise categoriesEMTAK

m3

ETC- grey Estimations-white Stat office survey-black

0 10 20 30 40 50 60 70 80 90 100

15

17

18

19

20

21

221

222

23

24

25

26

27

28

29

30

31

32

33

34

35

36

ETC- grey, estimation-white, Stat office survey-black

“Waste water generated”, the share of discharges of three enterprise categories in total of the economic activity

The estimation of pollution

The estimation of pollution (P, N, BOD, suspended solids) in industrial wastewater was performed in two locations of the

wastewater flow:Generation Discharge to environment

IWWTP = Industrial waste water treatment plant

UWWTP = Urban waste water treatment plant

POINT SOURCES: Agriculture

Industrial Activities (WW_5)•Mining and quarrying•Manufacturing Industry•Prod./Distr. Electricity•Construction

Domestic Sector (WW_4)•Other activities•Households

NON-POINT SOURCES:• Run-off rainwater• Agriculture

• Atmospheric deposition

Urban Waste Water Collecting

System

IWWTP

WW 6.3WW 4.1

WW 5.2.2

WW 7.1

WW 4.2.2

WW 6

WW 6.1

WW 5.2.1

Waste water loading scheme

UWWTP

P

WW 4.2.1

WW 7.2

Independent

treatment

INLAND

WATER

S

Rainwater run-off from paved area, infiltration and drainage into collecting system

Drainage from soils, direct transfers etc.

WW 5.2

WW 4.2

WW 5.1

WW 7

WW 6.2

...for each economic

activity group, NACE 2 digit

level...

Allocation to economic activities of the pollution loads of wastewater discharged to the environment was performed using

average loads

Total pollution quantities inwaste water

Cooling waterpollution load

Industrial and everyday waste waterpollution load

Average load directed to

environment:BHT7: 18,6

total-N: 35, 0total-P: 2,1

suspended solids: 27,9

Average load directed to

environment:BHT7: 3,8 g/m3

total-N: 2,4total-P: 0,1suspended solids: 13,2

...for each economic

activity group...

Presumtion: all NACE branches were

treated similarly in sense of pollution

concentration

Pollution load of discharged wastewater

OTHER COOLING WATER TOTAL OTHER

COOLING WATER TOTAL OTHER

COOLING WATER TOTAL OTHER

COOLINGWATER TOTAL

15 96,959 0,782 97,741 144,981 2,704 147,685 182,279 0,495 182,774 11,145 0,024 11,169 17 20,320 0,000 20,320 30,384 0,000 30,384 38,200 0,000 38,200 2,336 0,000 2,336 18 3,611 0,000 3,611 5,400 0,000 5,400 6,789 0,000 6,789 0,415 0,000 0,415 19 0,111 0,000 0,111 0,166 0,000 0,166 0,209 0,000 0,209 0,013 0,000 0,013 20 6,449 0,000 6,449 9,643 0,000 9,643 12,124 0,000 12,124 0,741 0,000 0,741 21 36,130 8,307 44,436 54,024 28,728 82,751 67,922 5,260 73,182 4,153 0,257 4,410

221 0,019 0,000 0,019 0,028 0,000 0,028 0,035 0,000 0,035 0,002 0,000 0,002

222 2,117 0,051 2,168 3,165 0,178 3,343 3,980 0,033 4,012 0,243 0,002 0,245 23 9,862 0,000 9,862 14,747 0,000 14,747 18,541 0,000 18,541 1,134 0,000 1,134 24 5,104 12,444 17,548 7,632 43,037 50,669 9,595 7,880 17,475 0,587 0,385 0,972 25 0,057 0,019 0,075 0,085 0,064 0,149 0,107 0,012 0,119 0,007 0,001 0,007 26 2,101 1,118 3,218 3,141 3,865 7,006 3,949 0,708 4,657 0,241 0,035 0,276 27 0,047 0,001 0,048 0,071 0,002 0,073 0,089 0,000 0,089 0,005 0,000 0,005 28 2,980 0,045 3,024 4,455 0,155 4,610 5,602 0,028 5,630 0,342 0,001 0,344 29 0,727 0,011 0,738 1,088 0,037 1,125 1,368 0,007 1,374 0,084 0,000 0,084 30 0,000 0,000 0,000 0,000 0,000 0,000 0,000 0,000 0,000 0,000 0,000 0,000 31 0,026 0,029 0,055 0,039 0,099 0,138 0,049 0,018 0,067 0,003 0,001 0,004 32 0,879 0,048 0,927 1,314 0,167 1,481 1,653 0,031 1,683 0,101 0,001 0,103 33 2,162 0,000 2,162 3,233 0,000 3,233 4,064 0,000 4,064 0,248 0,000 0,248 34 0,266 0,017 0,283 0,397 0,060 0,458 0,499 0,011 0,510 0,031 0,001 0,031 35 0,039 0,026 0,065 0,058 0,088 0,147 0,074 0,016 0,090 0,004 0,001 0,005 36 4,195 0,000 4,195 6,272 0,000 6,272 7,886 0,000 7,886 0,482 0,000 0,482

194,160 22,897 217,057 290,323 79,184 369,507 365,012 14,498 379,510 22,318 0,708 23,027

NACE BOD

susp sol tot-N tot-P

Calculation of generated by indstry sector wastewater loadings, before treatment

Wastewater treatment plants inflow monitoring data were used for the calculations of the generated wastewater pollution parameters

Presumption:One inhabitat consumes daily in average 127 litres water and generates the same amount of wastewater (expert opinion)

Wastewater treatment plants were devided 1) URBAN2) Other (industrial included)

“URBAN” treatment plants

treated wastewater 111 828 592 served inhabitants 947 090 waste water of inhabitants 43 902 342 191 treatment plants average BOD of inflow 301,303 g/m3 192 treatment plants average content of suspended solids in inflow 262,759 g/m3 188 treatment plants average content of tot-N in inflow 61,394 g/m3 186 treatment plants average content of tot-P in inflow 12,672 g/m3

Source data

Source data

Other treatment plants treated wastewater 164 445 860 served inhabitants 22 879 waste water of inhabitants 2 656 006 mining water 157 154 900 industrial wastewater without mining water 4 634 954 142 treatment plants average BOD of inflow 467,741 g/m3 162 treatment plants average content of suspended solids in inflow 266,124 g/m3 130 treatment plants average content of tot-N in inflow 67,271 g/m3 127 treatment plants average content of tot-P in inflow 15,170 g/m3

Urban treatment plants Other treatment

plants

Industrial water Inhabitants water

Pollution concentrationBOD 318,0 g/m3Susp sol 384,9 g/m3Tot N 61,9 g/m3Tot P 12,9 g/m3

Pollution concentrationBOD 301,3 g/m3Susp sol 262,8 g/m3Tot N 61,4 g/m3Tot P 12,7 g/m3

For industrial and inhabitants wastewater

the summary quantities andaverage pollutants

concentrationswere found

For the allocation to the NACE categories the pollution quantities of the generated wastewater, the following presumptions were made:

“Wastewater originating from industry” pollution loadings are distributed proportionally to the generated wastewater quantities.

“Everyday wastewater originating from industry” pollution loadings concentrations are considered to be equal to the inhabitants wastewater parameters

Wastewater generated

from production

cooling water

everyday use Wastewater from production proccesses

BOD SUSP SOL N tot P tot

m3 m3 m3 m3 tons tons tons tons 15 6 368 299 5 205 582 205 038 957 679 1 655,510 2 003,790 322,668 67,272 17 2 265 730 1 090 942 0 1 174 788 346,948 419,937 67,622 14,098 18 492 578 193 872 0 298 706 61,656 74,627 12,017 2,505 19 105 620 5 971 0 99 649 1,899 2,298 0,370 0,077 20 1 321 994 346 237 0 975 757 110,112 133,277 21,461 4,474 21 8 053 218 1 939 742 2 177 987 3 935 489 616,888 746,667 120,235 25,067

221 18 064 998 0 17 066 0,318 0,384 0,062 0,013 222 155 254 113 653 13 480 28 120 36,145 43,749 7,045 1,469

23 529 500 529 500 0 0 168,395 203,821 32,821 6,843 24 3 871 310 274 022 3 262 832 334 457 87,146 105,479 16,985 3,541 25 52 200 3 059 4 855 44 286 0,973 1,177 0,190 0,040 26 1 050 510 112 787 293 023 644 700 35,869 43,415 6,991 1,458 27 8 468 2 546 140 5 783 0,810 0,980 0,158 0,033 28 265 352 159 972 11 736 93 644 50,875 61,578 9,916 2,067 29 143 567 39 055 2 813 101 699 12,420 15,033 2,421 0,505 30 1 109 0 0 1 109 0,000 0,000 0,000 0,000 31 41 879 1 400 7 503 32 976 0,445 0,539 0,087 0,018 32 112 827 47 195 12 653 52 980 15,009 18,167 2,925 0,610 33 134 636 116 065 0 18 571 36,912 44,677 7,194 1,500 34 33 977 14 262 4 575 15 140 4,536 5,490 0,884 0,184 35 82 126 2 099 6 690 73 337 0,668 0,808 0,130 0,027 36 516 057 225 200 0 290 857 71,620 86,687 13,959 2,910

25 624 275 10 424 157 6 003 325 9 196 793 3 315,153 4 012,581 646,141 134,711

Wastewater generated by economic activities, quantities, BOD, susp, N, P

Wastewater generated by economic activities, quantities, BOD, susp, N, P everyday use cooling water

BOD susp sol N-tot P-tot BOD susp sol N tot P tot

15 402,216 280,330 61,854 13,841 0,782 2,704 0,495 0,024 17 493,400 343,882 75,876 16,979 0,000 0,000 0,000 0,000 18 125,454 87,437 19,293 4,317 0,000 0,000 0,000 0,000 19 41,852 29,169 6,436 1,440 0,000 0,000 0,000 0,000 20 409,809 285,622 63,021 14,103 0,000 0,000 0,000 0,000 21 1 652,870 1 151,988 254,181 56,880 8,307 28,728 5,260 0,257

221 7,167 4,995 1,102 0,247 0,000 0,000 0,000 0,000 222 11,810 8,231 1,816 0,406 0,051 0,178 0,033 0,002

23 0,000 0,000 0,000 0,000 0,000 0,000 0,000 0,000 24 140,469 97,902 21,602 4,834 12,444 43,037 7,880 0,385 25 18,600 12,963 2,860 0,640 0,019 0,064 0,012 0,001 26 270,768 188,715 41,639 9,318 1,118 3,865 0,708 0,035 27 2,429 1,693 0,374 0,084 0,001 0,002 0,000 0,000 28 39,330 27,411 6,048 1,353 0,045 0,155 0,028 0,001 29 42,713 29,769 6,568 1,470 0,011 0,037 0,007 0,000 30 0,466 0,325 0,072 0,016 0,000 0,000 0,000 0,000 31 13,850 9,653 2,130 0,477 0,029 0,099 0,018 0,001 32 22,251 15,508 3,422 0,766 0,048 0,167 0,031 0,001 33 7,800 5,436 1,199 0,268 0,000 0,000 0,000 0,000 34 6,358 4,432 0,978 0,219 0,017 0,060 0,011 0,001 35 30,801 21,467 4,737 1,060 0,026 0,088 0,016 0,001

36 122,157 85,139 18,786 4,204 0,000 0,000 0,000 0,000

3 862,570 2 692,067 593,993 132,921 22,897 79,184 14,498 0,708

Wastewater generated by economic activities, quantities, BOD, susp, N, P BOD susp sol N- tot P-tot

15 2 058,509 2 286,824 385,017 81,137 17 840,348 763,819 143,498 31,077 18 187,110 162,064 31,310 6,823 19 43,751 31,468 6,806 1,517 20 519,922 418,899 84,483 18,577 21 2 278,065 1 927,383 379,676 82,204

221 7,485 5,380 1,164 0,260 222 48,006 52,158 8,894 1,877

23 168,395 203,821 32,821 6,843 24 240,059 246,418 46,467 8,760 25 19,591 14,205 3,062 0,680 26 307,755 235,995 49,338 10,810 27 3,239 2,675 0,532 0,116 28 90,249 89,144 15,992 3,422 29 55,144 44,840 8,996 1,975 30 0,466 0,325 0,072 0,016 31 14,323 10,291 2,235 0,496 32 37,308 33,842 6,378 1,377 33 44,711 50,113 8,394 1,768 34 10,912 9,982 1,873 0,404 35 31,494 22,363 4,883 1,088

36 193,777 171,826 32,745 7,114 7 200,620 6 783,832 1 254,633 268,341

Calculations on the bases of M.Zessner, S.Lindtner "A method for load estimations of municipal point source pollution”.

Pollution generated by industry was found as difference between total pollution and pollution generated by inhabitants

Pollution generated by inhabitants was calculated using parametres found from literature

The comparison was made between the estimations based on wastewater treatment plants data and the other ones based on parametres found from literature

Parameters: M.Zessner, S.Lindtner "A method for load estimations of municipal point source pollution”

One inhabitat is daily generating in average:

60g of BOD 511g of N-tot1,6g of P-tot

Presumption

BHT5 = BHT7

Comparison of estimations on pollution quantities and loads by two methods

Estimations based on wastewater treatment plants inflows

M.Zessner, S.Lindtner

Estimations based on wastewater treatment plants inflows

M.Zessner, S.Lindtner

Wastewater of inhabitants tons g/m3 wastewater m3 46 558 348 BOD 14 028,15 21 242,00 301,30 456,24 N-tot 2 858,41 3 894,37 61,39 83,64

P-tot 589,98 566,45 12,67 13,35 Industrial waste water

wastewater m3 72 561 203,58 BOD 22 634,31 15 862,53 318,03 218,61 N-tot 4 482,07 3 461,72 61,98 47,71 P-tot 931,07 961,23 12,92 13,25

Differences are bigger in

activities there the

share of the use of

everyday water is bigger

Comparison of pollution estimations on NACE 2 digit level

Differences of estimations

(tons) Differences of estimations

(%) BOD N-tot P-tot BOD N-tot P-tot

15 482,8 56,1 -0,6 23,5 14,6 -0,8

17 65,9 -6,8 0,9 7,8 -4,7 3,0

18 8,4 -2,9 0,3 4,5 -9,3 3,9 19 -3,0 -1,8 0,1 -6,9 -26,7 7,1

20 -1,0 -13,7 1,0 -0,2 -16,2 5,2

21 50,2 -47,3 3,7 2,2 -12,5 4,5

221 -0,5 -0,3 0,0 -6,9 -26,7 7,3

222 10,3 1,1 0,0 21,4 12,2 -0,3

23 52,6 7,6 -0,2 31,3 23,0 -2,5 24 15,1 -2,5 0,3 6,3 -5,3 3,2

25 -1,3 -0,8 0,0 -6,6 -26,1 7,1

26 -12,2 -10,7 0,7 -4,0 -21,6 6,2

27 0,0 -0,1 0,0 1,3 -13,9 4,3

28 12,5 0,5 0,1 13,9 3,1 1,5

29 0,2 -1,4 0,1 0,4 -15,4 5,0 30 0,0 0,0 0,0 -8,6 -29,2 6,3

31 -1,1 -0,6 0,0 -7,4 -27,2 7,3

32 2,8 -0,3 0,0 7,4 -5,3 3,1

33 10,9 1,3 0,0 24,3 15,5 -1,0

34 0,9 -0,1 0,0 8,0 -4,5 3,0 35 -2,5 -1,4 0,1 -7,8 -28,0 7,4

36 11,8 -2,3 0,2 6,1 -7,1 3,5

702,9 -26,4 6,7 9,8 -2,1 2,5

Testing of the methodology for the estimation of the generated (inflow to

treatment plants) wastewater pollution (N and P)

The pollutant quantities calculated according to “M.Zessner, S.Lindtner “A method for load

estimations of municipal point source pollution” ” were compared to monitoring data of 138 urban

wastewater treatment plants

For the comparison the data of the 138 urban waste water

treatment plants were used for which all necessary parameters

existed in database:

BOD of inflow

N- tot of inflow

P-tot of inflow

Quantity of wastewater treated

Number of connected population

Designed capacity

Avarage characteristics of wastewater stemming from households:11g N / pe.d1,6g P / pe.d

Avarage characteristics of wastewater stemming from industry: 6,5g N / pe.d 1,3g P / pe.d

Avarage characteristics of inflow to wastewater treatment palnts: 8,8g N / pe.d1,5g P / pe.d

At least data of 20 wastewater treatment plants are needed

pe.d = 60g BOD daily

Wasteater treatment plants work at 63% of designed capacity

The relation between N and P in inflow is 6:1

Our presumption: BOD 5=BOD7

Source parametres used in calculations

In M.Zessner, S.Lindtner “A method for load estimations of municipal point source pollution” 5 possibilities is given for calculation of N-tot and P-tot load in influents.

Assumption 1

Only the design capacity of a treatment plant is known

Assumption 2

Design capacity and connected inhabitants are known

Assumption 3

The BOD-influent load is known from measurements

Assumption 4

The N-tot or P-tot influent loads are known from measurements

Assumption 5

The BOD-influent load and the connected inhabitants are known

N-tot, tons

difference, tons

difference, %

P-tot, tons

difference, tons

difference,%

Monitoring

data* 3 950,2 709,8

Calculated** Assumption 1 4 159,5 209,3 5,3 709,0 -0,8 -0,1 Assumption 2 4 453,9 503,7 12,8 706,6 -3,2 -0,5 Assumption 3 3 446,6 -503,6 -12,7 587,5 -122,3 -17,2 Assumption 4 4 164,0 213,8 5,4 673,3 -36,5 -5,1 Assumption 5 3 927,3 -22,9 -0,6 601,3 -108,5 -15,3 *Total of 138 urban wastewater treatment plants **According to M.Zessner, S.Lindtner “A method for load estimations of municipal point source pollution”

Comparisons of calculated nitrogen and phosphorus quantities with monitoring data

Sources of errors:

1. BOD7 is used in Estonia (BOD5 in Austria)

2. The nitrogen and phosphorus loads relation in Estonian wastewater is 5:1 (6:1 in Austria)

3. In Estonia the population equivalent (pe) is less than 60

4. The designed capacity of wastewater treatment plants and the real capacity could be very different

Further steps:

Second meeting of the steering group

Recalculations based on BOD 5 (and the Estonian people equivalent of BOD)

Recalculations of N and P loads in generated wasteater by economic activities

Writing of the final report