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Determinants of Energy Consumption in the Dairy Industry: A Case Study in Poland Cover

Determinants of Energy Consumption in the Dairy Industry: A Case Study in Poland

Open Access
|Dec 2023

Figures & Tables

Figure 1.

Energy and water consumption in a dairy plant (detailed explanations in the text)
Energy and water consumption in a dairy plant (detailed explanations in the text)

Figure 2.

Indicators of energy consumption per unit of end product in a dairy plant (detailed explanations are in the text)
Indicators of energy consumption per unit of end product in a dairy plant (detailed explanations are in the text)

Figure 3.

The influence of the production profile on electric energy and heat consumption (summer)
The influence of the production profile on electric energy and heat consumption (summer)

Figure 4.

The influence of the production profile on electric energy and heat consumption (winter)
The influence of the production profile on electric energy and heat consumption (winter)

Figure 5.

The influence of the installed capacity of electrical devices on electric energy and heat consumption (summer)
The influence of the installed capacity of electrical devices on electric energy and heat consumption (summer)

Figure 6.

The influence of the installed capacity of electrical devices on electric energy and heat consumption (winter)
The influence of the installed capacity of electrical devices on electric energy and heat consumption (winter)

Figure 7a.

Variation in the indicators of heat consumption per unit of end product in the different types of dairy plants analysed
Variation in the indicators of heat consumption per unit of end product in the different types of dairy plants analysed

Figure 7b.

Thermal efficiency (EEtherm) in the different types of dairy plants analysed
Thermal efficiency (EEtherm) in the different types of dairy plants analysed

Figure 8a.

Variation in the indicators of electric energy consumption per unit of end product in the different types of dairy plants analysed
Variation in the indicators of electric energy consumption per unit of end product in the different types of dairy plants analysed

Figure 8b.

Electric energy efficiency (EEel) in the different types of dairy plants analysed
Electric energy efficiency (EEel) in the different types of dairy plants analysed

Figure 9.

Winter increase in heat consumption per unit of end product in the types of dairy plants analysed, relative to the summer season
Winter increase in heat consumption per unit of end product in the types of dairy plants analysed, relative to the summer season

Technological factors influencing energy demand in selected dairy plants

Dairy plant specificationAverage electric energy consumptionSeasonRegression equationsCorrelation coefficient rIndependent variables’ range of variation
  • T1 (1)

  • P = 2500 kW

  • Km= 17.67 kW/1000L

  • Z = 4,657,840 L/month

Ae = 488731.7 kWh/monthS/WAe = 38530 + 21.93Zm0.917Zm: 4,058.9 – 6348.8 m3/month
We = 104.9 kWh/1000LWe = 178.6 - 0.019Zm−0.982
  • T4 (1)

  • P = 5400 kW

  • Km = 6.9 kW/1000 L

  • Z = 777,626 L/24h

Ae = 1842461 kWh/monthS/WAe = 80.184 - 74908Zm0.63
  • Zm: 21749 – 25541 Mg/month

  • Z11: 3597 – 5653 Mg/month

  • Z12: 4,956 – 6240 Mg/month

  • Z13: 113 – 204 Mg/month

  • Z14: 456 – 782 Mg/month

  • Z15: 2184 – 3023 Mg/month

Ae = 155.75·Z11+84.68·Z12 - 573.45·Z13–11.36·Z14+232.33·Z15 + 139383.530.72
We = 77.0 kWh/1000 LWe = 0.0002 Zm + 72.558Weak correlation
We = 3∙10−3 Z11 + 7∙10−3·Z12 - 0.017·Z13 - 0.025·Z14 + 3∙10−3·Z16 + 36.50.31
Ac = 17060.39 GJ/monthAc = 0.0946Zm + 14799Weak correlation
Ac= −1.49·Z11 - 1.33·Z12 + 3.46·Z13 + 5.84·Z14 + 3.93·Z15 + 16572.400.65
Wc = 0.71 GJ/1000 LWc= −3E-05Zm + 1.34410.47
Wc = −1∙105·Z11 - 3∙105·Z12 + 2∙104·Z13 + 7∙10−6 ·Z14 + 1∙10−5 ·Z15 + 0.990.83
  • T4 (2)

  • P = 420 kW

  • Km = 3.2 kW/1000L

  • Z = 132,765 L/24h

Ae = 101,516 kWh/monthS/WAe = 16.039 Zm + 376320.741
  • Zm: 2,678.12 – 5,276.36 m3/month

  • Z16: 5,171 – 9,293 dm3/month

  • Z17: 29,191 – 44,207 dm3/month

  • Z18: 24,000 – 299,045 dm3/month

  • Z19: 1,184–3,388 dm3/month

  • Z20: 3,962 – 35,914 kg/month

  • Z21: 10,593 – 13,790 kg/month

  • Z22: 37,806 –187,223 kg/month

  • Z23: 281 – 3079 kg/month

Ae = 0.17·Z16 + 3.38·Z17 + 0.32·Z18 - 0.70·Z19 + 1.62·Z20 + 0.48·Z21 + 0.08·Z22 - 0.84·Z23 - 15048.700.984
We = 25.94 kWh/1000 LWe = −0.0025 Zm + 35.7950.526
We = 5∙10−6 ·Z16 - 0.002·Z17 + 4∙10−6·Z18 - 0.001·Z19 - 0.004·Z20 + 4∙10−6 ·Z21 + 2∙10−6·Z22 + 0.002·Z23 + 59.290.905
  • T4 (3)

  • P = 300 kW

  • Km = 6.6 kW/1000L

  • Z4d = 181,300 L/96 h

Ae = 10,681 kWh/4dS/WAe = 84.71Z4d - 4676.820.675Z4d: 173,430 – 192,500 L/4d
We = 58.87 kWh/m3We = 0.1479Z4d + 31.750.285
Ac = 56.93 GJ/4dAc = 0.6966Z4d - 69.360.719
Wc = 313.56 MJ/m3Wc = 2.00 Z4d - 48.810.482

Influence of the daily production profile and the installed capacity of electrical devices on energy consumption in T4 dairy plants (producing only milk, dairy beverages, tvorog, and, in some cases, also butter)

SeasonTotal installed capacity P [kW]Average energy consumptionAverage energy consumption per unit of end productMultiple regression equationCoefficient of determination R2Range of variation in independent variables
Ae [kWh /24h]Ac [GJ/24h]We [kWh/1000 L]Wc [GJ/1000 L]
S50.0 – 2,385.0 (34)2,374.159.30532.131.0882Ae = 559.42 + 29.374Z10.834Z1: 2.5 – 80.6
Ae =345.63 + 4.420P1 + 18.787P20.950
  • P1: 0.0 –1785.0

  • P2: 7.5 –170.0

Ac = 18.658 + 0.460 Z1 + 1.766Z20.849
  • Z1: 2.5 – 80.6

  • Z2: 3.1 – 39.6

W63.0 – 646.0 (24)1,081.452.36630.701.7502Ae = 358.08 + 35.352Z10.672Z1: 1.0 – 59.1
Ae = 463.75 + 6.235P30.429P3: 6.0 – 250.0
Ac = −0.121 + 0.531P1 − 1.899P70.811
  • P1: 17.4 – 273.7

  • P7: 0.0 – 41.2

Ac = 30.777 + 1.054Z10.441Z1: 1.0 – 59.1

Types of examined dairy plants

TypeProduction profile
T1Milk, dairy beverages, cream, tvorog, cheese, butter, casein, milk powder
T2Identical to T1 plants, excluding milk powder
T3Identical to T1 plants, excluding milk, dairy beverages, cream, and tvorog
T4Milk, dairy beverages, cream, and tvorog only

Literature on energy consumption and environmental performance of dairy plants

Research topicAuthors
Energy consumption (direct) and energy conservationBudny & Weiss [2000], Baker & McKenzie [2005], Benedetti et al. [2016], Biglia et al. [2015], Boutaghriout et al. [2016], Bühler et al. [2018], Cosgrove et al. [2016], De Lima et al. [2018], Domínguez-Niño et al. [2017], Energy Performance Indicator Report [2001], Fushimi & Fukui [2014], Gugała et al. [2015], IFC – World Bank Group [2007], Herbst & Griffiths [1993], Kalla et al. [2017], Kapela et al. [2015], Marchi et al. [2022], Masanet et al. [2014], Milani et al. [2011], Pradella et al. [2017], Rad & Lewis [2014], Ramirez et al. [2006], Rao [1986], Samarin et al. [2020], Srinivasan et al. [2018], Wardrop Engineering Inc. [1997], WS Atkins [1998], Wojdalski [1991], Xu & Flapper [2009], Xu et al. [2012], Zhang et al. [2018].
Heat recoveryAtkins et al. [2011], Atkins et al. [2010], Jbira et al. [2023]
Energy consumption in wastewater treatmentKowalczyk & Karp [2005], Dąbrowski & Żyłka [2015], Grala et al. [2010], Kowalczyk & Bąbała [2010], Krzemińska et al. [2013].
Renewable energySchnitzer et al. [2007], Coskun et al. [2012]
Cleaner production standardsBosworth et al. [2000], Honkasalo et al. [2005].
Best available techniquesBosworth et al. [2000], WS Atkins [2005]
Environmental performanceBurnett & Hansen [2008], Honkasalo [2003], Honkasalo et al. [2005], Maxime et al. [2006], Prasad et al. [2004], Prasad & Pagan [2006], Zielińska-Chmielewska [2020].
Energy efficiency and optimization of selected production processesAlves et al. [2014], Baker [2005], Bouman et al. [1993], Brush et al. [2011], Dobry et al. [2009], Đurić et al. [2005], Erbay et al. [2015], Gawałek & Wesołowski [2008], Jin & Chen [2009; 2011], Johnson & Langrish [2017], Jokandan et al. [2015], Kaleta & Chojnacka [2009], Kemp [2012], Leszczyńska & Lee [2016], Marks & Gut [2007], Moejes & Van Boxtel [2017], Munir et al. [2016], Murphy et al. [2013], Niamsuwan et al. [2013], Palianechka et al. [2022], Patel et al. [2009], Philipp et al. [2018], Písecký [2005; 2012], Raghavan et al. [2004], Seydel et al. [2006], Sikirica et al. [2003], Sorgüven & Özilgen [2012], Taghizadeh-Tabari et al. [2016], Walmsley et al. [2013], Yildirim & Genc [2017].
Financial and environmental implications of energy managementAymerich et al. [2015], Chauhan et al. [2006], Dalton et al. [2002], Egas et al. [2021], Geary et al. [2010].
Process integrationAtkins et al. [2010; 2011], Chen et al. [2022], Kapustenko et al. [2008], Jbira et al. [2023], Kemp [2005], Lincoln et al. [2022], Schlossera et al. [2019], Walmsley et al. [2016; 2018].
Pulsed electric field processingBendicho et al. [2002], Guerrero-Beltrán et al. [2010], Sepulveda et al. [2005]
Solar energyBoutaghriout et al. [2013], Camci [2020], Panchal et al. [2018]), Schnitzer et al. [2007]
Electric power substitution/electrificationBühler et al. [2019]
Life cycle assessment (LCA), carbon footprint (CF), sustainable development standardsDjekič et al. [2014], Egas et al. [2021], Kim et al. [2013], Prakash & Henham [2014], Vasilaki et al. [2016], Vergé et al. [2007], Von Keyserlingk et al. [2013], Walmsley et al. [2015]
Cleaner production and the environmental impact of dairy productionDvarionienė et al. [2012], Dyer et al. [2008], Komisja Europejska [2010], Nutter et al. [2013], Özbay & Demirer [2007], Patankar et al. [2010], Saunders & Barber [2007]
Cleaning of production equipmentJeurnink & Brinkman [1994], Mierzejewska & Diakun [2011], Muthukumaran et al. [2004], Piepiórka-Stepuk et al. [2017]

General characteristics of the analysed types of dairy plants in summer and winter

FR1Type of plant (Summer)Type of plant (Winter)
T1T2T3T4T1T2T3T4
Kp10.59 – 3.100.36 – 5.660.54 – 3.100.62 – 2.420.32 – 2.900.22 – 2.990.25 – 2.900.40 – 1.16
Kp20.35 – 1.330.23 – 3.540.30 – 2.130.14 – 0.820.19 – 1.180.13 – 2.460.13 – 1.350.18 – 0.90
Uen13.52 – 17.743.93 – 40.465.30 – 31.671.13 – 21.404.13 – 17.741.16 – 39.551.17 – 17.742.26 – 13.53
Uen22.43 – 12.911.26 – 23.753.06 – 23.750.49 – 8.930.70 – 13.161.02 – 32.411.08 – 11.921.31 – 8.77
Km3.74 – 13.692.63 – 28.794.02 – 28.790.99 – 24.661.76 – 24.661.99 – 34.331.99 – 32.263.38 – 24.64

Influence of the daily production profile and the installed capacity of electrical devices on energy consumption in T3 dairy plants (not producing milk, dairy beverages or tvorog)

SeasonTotal installed capacity P [kW]Average energy consumptionAverage energy consumption per unit of end productMultiple regression equationCoefficient of determination R2Range of variation in independent variables
Ae [kWh/24h]Ac [GJ/24h]We [kWh/1000 L]Wc [GJ/1000 L]
S83.0 – 1,923.0 (22)3,079.5148.15137.831.5542Ae = 953.19 + 29.707Z4 + 430.898Z60.932
  • Z4: 10.0 – 335.8

  • Z6: 0 – 22.5

We = 42.633 - 0.481Z50.346Z5: 0 – 80.3
Ac = −36.781 + 0.607P1 - 0.523P3 + 1.037P4 + 0.968P6 + 5.555P100.990
  • P1: 30.3 – 574.0

  • P3: 0.0 – 320.0

  • P4: 0.0 – 592.0

  • P6: 0.0 – 58.6

  • P10: 0.0 – 101.0

Wc = 1.476 + 0.001P4 - 0.012P6+0.013P100.662
Ac = 41.899 - 0.964Z3 + 2.204Z4 + 15.219Z60.971
  • Z3: 0 – 164.2

  • Z4: 10.0 – 335.8

  • Z5: 0– 80.3

  • Z6: 0 – 22.5

Wc = 1.6316-0.006Z3 + 0.003Z4 - 0.013Z50.608
W30.3 – 1,938.0 (20)3,548.8230.24342.822.9086
  • Ae = 2133.00 - 85.291Z4

  • We = 32.375 + 5.757Z6

  • 0.660

  • 0.770

  • Z4: 0 – 53.0

  • Z6: 0 – 7.9

Ac = 1.145 + 0.444P1 + 0.936P4 + 1.275P70.985
  • P1: 30.3 – 470.0

  • P4: 0.0 – 592.0

  • P7: 0.0 – 87.0

Wc = 2.2652 + 0.028P70.627
Ac = 117.423 + 62.187Z60.399Z6: 0 – 7.9
Wc = 2,3795 + 0.291Z60.563

Factors that influence energy consumption in dairy production

Group of factorsMeasured parametersSymbols*
FR1Basic operating parameters and process automationKm, Kp1, Kp2, N1, N2, P, Uen1, Uen2, Z, Zm, Z4d
FR2Production profile**Z1, Z2, Z3, Z4, Z5, Z6, Z7, Z8, Z9, Z10, Z11, Z12, Z13, Z14, Z15, Z16, Z17, Z18, Z19, Z20, Z21, Z22, Z23
FR3Technical equipmentP1, P2, P3, P4, P5, P6, P7, P8

Influence of the daily production profile and the installed capacity of electrical devices on energy consumption in T1 dairy plants (producing milk powder)

SeasonTotal installed capacity P [kW]Average energy consumptionAverage energy consumption per unit of end productMultiple regression equationCoefficient of determination R2Range of variation in independent variables
Ae [kWh/24h]Ac [GJ/24h]We [kWh/1000 L]Wc [GJ/1000 L]
S454.0 – 2,421.7 (21)7,682.1432.65041.732.3207Ae = 3944.70 + 37.110 Z40.568Z4:19.0 – 335.8
Ac = 134.293 + 0.546P2 + 0.760P40.789
  • P2: 31.0 – 777.0

  • P4: 100.0 – 964.0

Ac = 140.56 + 2.433Z4 + 1.977Z5 + 0.815 Z80.834
  • Z4: 19.0 – 335.8

  • Z5: 0 – 81.8

  • Z8: 0 – 335.8

W318.0–2,548.0 (19)6,246.0396.63252.703.4125Ae = 4289.00 + 41.401Z4 for Wc R2 < 0.200.502Z4: 10.4 –282.7
Ac = 83.369 + 0.530P2 + 0.644P4 + 0.857P10 for Wc R2 < 0.340.846
  • P2: 31.0 – 777.0

  • P4: 100.0 – 964.0

  • P10: 0.0 – 358.3

Ac = 246.86 + 3.168 Z40.546Z4: 10.4 – 282.7

Selected indicators and factors for analysing the energy performance of dairy plants

Indicators and factors for analysing energy performanceUnit of measureType of plant/production profile/productIndicatorsSource
Range according to Fig. 2MeanInterval/season
Electric energy consumptionkWh/m3 of raw milkTotal productionWZ9010 – 680WS Atkins [1998]
kWh/m3 of milkMilk powder, cheese, butter, yogurt, dairy desserts27-Budny & Weiss [2000]
Cheese, tvorog, yogurt, dairy desserts32-
Cheese, butter, yogurt, dairy desserts-34 – 52
Butter, milk powder, yogurt, dairy desserts-53 – 57
Cheese, milk powder, butter64
Cheese, butter65
Yogurt, dairy desserts, tvorog, butter66
kWh/m3 of milkCheeseWT-2.9 – 6.6
kWh/Mg of butterButter (continuous method)-12.9 – 17.0
kWh/Mg of milkMilk processing output (based a study of three dairy plants)WZ-30 – 80Boutaghriou et al. [2016]
kWh/Mg of end productMilk powderWZ429.9377.0 – 482.9Budny et al. [1984a]
Heat consumptionGJ/m3 of raw milkTotal productionWZ2.010.12 – 14WS Atkins [1998]
MJ/m3 of processed milkMilk powder, cheese, butter, yogurt, dairy desserts1348-Budny & Weiss [2000]
Cheese, tvorog, yogurt, dairy desserts1439-
Cheese, butter, yogurt, dairy desserts-1583 – 2380
Butter, milk powder, yogurt, dairy desserts-2733 – 3171
Cheese, milk powder, butter2882-
Cheese, butter1884-
Yogurt, dairy desserts, tvorog, butter2698-
GJ/Mg of evaporated waterSpray-dryingWA4.873 – 20Baker & McKenzie [2005]
GJ/Mg of processed milkModern dairy plants with heat recovery systemsWZ0.34-Bosworth et al. [2001]
Modern plants where hot water is used as an energy carrier0.50-
Older plants where steam is used as an energy carrier2.00-
Total energy consumptionMWh/Mg of milk powderMilk powder (mechanical vapor recompression, MVR)WP3.08-Bühler et al. [2019]
GJ/Mg of productMilk powderWZ29.9526.41–33.49Budny et al. [1984a]
MWh/Mg of dry productSpray-drying of cheese wheyWA2.049-Domínguez-Niño et al. [2018]
Fuel gaskWh/Mg of milkTotal production (based on a study of three production plants)WZ-100 – 220Boutaghriou et al. [2016]
Total energy consumptionGJ/m3 of processed milk*Milk, tvorog (based on a study of a selected dairy plant)-3.041.93 – 2.47 SummerWojdalski et al. [2007]
3.63 – 4.19 Winter
GJ/m3 of processed milk**WZ2.461.40 –1.96 Summer
3.04 – 3.55 Winter
Total energy consumptionkWh/kg of evaporated waterThree-phase evaporatorWA0.14-Prasad et al. [2004]
Five-phase evaporator0.085-Prasad et al. [2004]
Total energy consumption expressed in fuel equivalentskg of fuel equivalent/m3 of processed milk*Milk, tvorog (based on a study of a selected dairy plant)WZ10466 – 84 SummerWojdalski et al. [2007]
124 –143 Winter
kg of fuel equivalent/m3 of processed milk**8448 – 67 Summer
103–121 Winter
Energy consumption in wastewater treatmentkWh/kg BOD5Total productionWT-0.89 – 3.22Kowalczyk & Karp [2005]
kWh/m3 of wastewater-1.94 – 6.32
SO2 emissionskg/m3 of raw milkTotal productionWZ1.650.05 – 22.4WS Atkins [1998]
kg/m3 of processed milk-0.83-Wojdalski et al. [2007]
NOx emissionskg/m3 of raw milkTotal productionWZ0.490.03 – 6.4WS Atkins [1998]
kg/m3 of processed milk-0.60-Wojdalski et al. [2007]
CO2 emissionskg/m3 of raw milkTotal productionWZ1.970.01 – 9.23WS Atkins [1998]
kg/m3 of processed milk 1.25-Wojdalski et al. [2007]
Carbon footprint of end productskg CO2eq/kg of butterButterWZ8.1-Flysjö et al. [2014]
kg CO2eq/kg of milk powderMilk powder7.4-
kg CO2eq/kg of cheeseCheese6.5-
kg CO2eq/kg of dairy beverageDairy beverages1.2-
Particulate-matter emissionskg/m3 of raw milkTotal production1.30.01 –14.4WS Atkins [1998]
kg/m3 of processed milkTotal productionWZ1.15-Wojdalski et al. [2007]
Black carbon emissionskg/m3 of raw milkTotal productionWZ190.01 – 193WS Atkins [1998]
kg/m3 of processed milkTotal production-0.04-Wojdalski et al. [2007]

Structure of energy consumption in the analysed dairy plant

Process/operation[kJ/Mg of milk]Percent share [%]
SteamDirect fuel consumptionRefrigerationOther machines and devicesTotal
End product storage--41,868-41,8689.46
Packing-3,489--3,4890.71
Storage before packing--20,934-20,9344.73
Deodorissation5,815---5,8151.32
Cooling--19,771-19,7714.47
Homogenisation---2,3262,3260.53
Pasteurisation213,992---213,99248.30
Separation---41,86841,8689.46
Clarification/Standardisation---20,93420,9344.73
Reception and Storage-30,23841,868-72,10616.29
Total219,80733,727124,44165,128443,103100

Influence of the daily production profile and the installed capacity of electrical devices on energy consumption in T2 dairy plants (not producing milk powder)

SeasonTotal installed capacity P [kW]Average energy consumptionAverage energy consumption per unit of end productMultiple regression equationCoefficient of determination R2Range of variation in independent variables
Ae [kWh/24h]Ac [GJ/24h]We [kWh/1000 L]Wc [GJ/1000 L]
S83.0 – 2,935.0 (37)3,289.9118.90939.521.3607Ae= 748.34 + 60.1453Z1 + 39.4929Z3 + 22.079Z5 + 75.286Z8 for We R2 < 0.320.442
  • Z1: 0 – 211

  • Z3: 0 – 164

  • Z5: 0 – 141

  • Z8: 0 – 157.5

Ac= 1.152 + 0.310P1 + 1.266P2 + 1.082P6 for Wc R2 < 0.370.860
  • P1: 24.4 – 1155.1

  • P2: 0.0 – 434.0

  • P6: 250.0 – 956.0

Ac= 18.295 + 1.501Z1 + 1.748Z2 + 0.990Z3 +1.006 Z5 −5.385 Z7 + 5.265 Z80.830
  • Z1: 0 – 211

  • Z2: 0 – 73

  • Z3: 0 – 164

  • Z5: 0 – 141

  • Z7: 0 – 44.4

  • Z8: 0 – 157.5

W30.3 – 1,938.0 (24)2129.3120.58139.922.4672Ae = 864.92 + 94.4138Z2 + 104.032Z8 for We R2 < 0.200.603
  • Z2: 0 – 63.6

  • Z8: 0 – 75.6

Ac = −4.109+0.364P1 +0.989P2+ 1.080P7 + 0.191P10 for Wc R2 < 0.330.896
  • P1: 30.3 – 708.0

  • P2: 0.0– 312.0

  • P7: 0.0 – 68.0

  • P10: 0.0 – 377.0

Ac = 26.259+2.981Z1 +2.492Z3 + 15.157Z7 + 6.733Z80.693
  • Z1: 0 – 111.6

  • Z3: 0 – 64.2

  • Z7: 0 – 9.9

  • Z8: 0 – 75.6

DOI: https://doi.org/10.2478/oszn-2023-0017 | Journal eISSN: 2353-8589 | Journal ISSN: 1230-7831
Language: English
Page range: 69 - 91
Published on: Dec 31, 2023
Published by: National Research Institute, Institute of Environmental Protection
In partnership with: Paradigm Publishing Services
Publication frequency: 4 issues per year
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© 2023 Janusz Wojdalski, Przemysław Ligenza, Marta Postuła, Bogdan Dróżdż, Roman Niżnikowski, published by National Research Institute, Institute of Environmental Protection
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.