Tools for Environmental Impact Assessment of Wastewater Treatment

1. Tools for Environmental Impact Assessment of Wastewater Treatment Manoj K. Pandey NMBU

2. Faculty of Environmental Sciences and Natural Resources Management

3. Concernsof wastewater treatment SO2 NOx CO2, N20; N2 The water industry is the fourth most energy intensive sector in the UK![1] ] Parliament Office of Science and Technology, Postnote 282, 2007 [2] (Lorentzen 1988) [1] Parliament Office of Science and Technology, Postnote 282, 2007 [2] (Lorentzen 1988) CH4, N2O CO2 CH4 Energy issue is much more important in Cold region (Arctic)

4. Wastewater discharge to marine waters – problems? • Trace Organic matters ? • Pathogens ? • Medicinalresidue [1] (Gardner 1996) Faculty of Environmental Sciences and Natural Resources Management 20-40% of the water consumption in sewered cities is used for flushing toilets[1]

5. Sustainablity Sustainable System? Technical Economy (Affordable) Environment Socio-cultural High performance Useoflocal material Robust and resilient Culturallycompatible Sociallyacceptable Communityparticipation Low fossil energyuse Resource conservation Reuse and recycling Public healthprotection Low capital cost Low O/M cost

6. Sustainability Analysis tools LCA (Life cycle analysis) CBA (Cost benefit analysis) AHP (Analytical hierarchy process)- Multi criteria decision making tool Environmental Audit Material flow analysis Environmental impact assessment (EIA) Department of Plant and Environmtental Sciences

7. Savingenergy and resources Less emissionsofharmfulsubstances Promotingrecycle and reuse What is LCA? Wasoriginallydeveloped to obtaincleanerproductionof Industrial products It analyses ofenvironmentalperformanceof a product ( or processes) from: Thereforethere is less chanceofenvironmentalburdenshifting GRAVE CRADLE

8. If minimizationofenvironmentalimpacts is oneofthemainfunctionsof wastewater treatment systems thentheyshould be designed so thattheir total impactontheenvironment is reduced [1] 45 LCA studies on wastewater have beenreported to be published in peer reviewed Journals [2] Numerousother studies published in the form of reports, thesis etc. [1] Dixon, A., et al. (2003). "Assessing the environmental impact of two options for small-scale wastewater treatment: comparing a reedbed and an aerated biological filter using a life cycle approach." Ecological Engineering20(4): 297. [2] Corominas, L., Foley, J., Guest, J. S., Hospido, A., Larsen, H. F., Morera, S., & Shaw, A. (2013). Life cycle assessment applied to wastewater treatment: state of the art. Water research, 47(15), 5480-5492. LCA exactlydoesthat !!!

9. What is Life cycleof wastewater treatment system? Households Solid waste Energy Construction Water emissions Material Modified from: Lundin, M., Bengtsson, M. and Molander, S (2000). "Life cycle assessment of wastewater systems: influence of system boundaries and scale on calculated environmental loads." Environmental Science and Technology34(1): 180-186. Airborne emissions Collection and transport Solid waste Energy Operation Water emissions Material Airborne emissions Wastewater treatment Energy Sludgetreatment Solid waste Demolition Material Water emissions Airborne emissions

10. LCA Framework Interpretation Goal and scope defination • Objectives of study • Functional unit • System boundaries Modified from: ISO 14040: Environmentalmanagment – lifecycleassessment- principles and framework. Geneva: International Standard Organizations, 1997 Inventory analysis Impactassessment

11. LCA Framework Interpretation Goal and scope defination • Data for material and energyconsumption during construction and operationof WWTP • Data for environmentalemission during construction, operation and demolition ???? Modified from: ISO 14040: Environmentalmanagment – lifecycleassessment- principles and framework. Geneva: International Standard Organizations, 1997 Inventory analysis Impactassessment

12. LCA Framework Interpretation Goal and scope defination • Impactcharacterization • Impactnormalization and weighing (optional) • Impactevaluation (optional) Modified from: ISO 14040: Environmentalmanagment – lifecycleassessment- principles and framework. Geneva: International Standard Organizations, 1997 Inventory analysis Impactassessment

13. LCA of WWT options for small and decentralizedcommunity (example) Wastewater infiltration in 2000 m2plantedwithPopulas euroamericana(40) - Wood cut- every 5 years; Used to produce pulp Machado, A. P., et al. (2006). Life cycle assessment of wastewater treatment options for small and decentralized communities. 10th International conference on wetland systems for water pollution control. Lisbon, Portugal. Willow system / slow rate infiltration Activatesludgemadeofstainlesssteel tanks with 2 aerators, sludgetreated and used for soilamendments HF bed- 277 m2; VF bed- 317 m2 ; PlantedwithPhragmitesaustralis;geotextiles as liner; gravel bed for thebiomassgrowth; Imhoff tank of PVC and concrete Activatedsludge Constructedwetland

14. LCA of WWT options for small and decentralizedcommunity Goal: to comparetwonatural systems (constructedwetland and willow/soilinfiltration) with a conventionalone. Functional unit: 1 Populationequivalent Design life: 10 years System Boundry: As shown in figure - Scope: Construction, operation, dismantling Machado, A. P., et al. (2006). Life cycle assessment of wastewater treatment options for small and decentralized communities. 10th International conference on wetland systems for water pollution control. Lisbon, Portugal.

15. LCA Framework Interpretation Goal and scope defination • Data for material and energyconsumption during construction and operationof WWTP • Data for environmentalemission during construction, operation and demolition ???? Modified from: ISO 14040: Environmentalmanagment – lifecycleassessment- principles and framework. Geneva: International Standard Organizations, 1997 Inventory analysis Impactassessment

16. Inventory table (1 p.e)

17. Life CycleAssessmentsoftware • Gabi • Open LCA – Free open source software • SimaPro Faculty of Environmental Sciences and Natural Resources Management

18. This is the opening screen of SimaPro • Click to proceed

19. LCA Framework Interpretation Goal and scope defination • Impactcharacterization • Impactnormalization and weighing (optional) • Impactevaluation (optional) Modified from: ISO 14040: Environmentalmanagment – lifecycleassessment- principles and framework. Geneva: International Standard Organizations, 1997 Inventory analysis Impactassessment

22. Process information and the amount produced The inputs from nature The inputs from the technosphere (manufacturing processes and resources) The inputs from the technosphere (manufacturing heat and electricity Direct emissions to the environment

23. Impactassessment Machado, A. P., et al. (2006). Life cycle assessment of wastewater treatment options for small and decentralized communities. 10th International conference on wetland systems for water pollution control. Lisbon, Portugal.

24. Critical issues in applicationof LCA Functional unit • Commonly used functional unit is m3 or ML oftreated water - could be misleading[1] • Unit populationequivalent (p.e)-includesbothquantity and qualityofwastwater (1 p.e = 60 g BOD/day) System boundry • System boundaries have significantimpactontheoutcomeof LCA result[1] • Boundryof thestudyshould be extended to fertilizerproduction and agriculturalapplication – especially for analysissourceseparatingsystems [2] • Most ofthe studies have excludeddemolitionphase [3] • For small system constructionphasecould have significantimpactonsomeimpactcategories • Data uncertainty [1] Corominas, L., Foley, J., Guest, J. S., Hospido, A., Larsen, H. F., Morera, S., & Shaw, A. (2013). Life cycle assessment applied to wastewater treatment: state of the art. Water research, 47(15), 5480-5492. [2] Lundin, M., Bengtsson, M. and Molander, S (2000). "Life cycle assessment of wastewater systems: influence of system boundaries and scale on calculated environmental loads." Environmental Science and Technology34(1): 180-186. [3] Corominas, L., Foley, J., Guest, J. S., Hospido, A., Larsen, H. F., Morera, S., & Shaw, A. (2013). Life cycle assessment applied to wastewater treatment: state of the art. Water research, 47(15), 5480-5492.

25. Weaknessof LCA Does not takesintoaccountsocial and culturalaspectsof wastewater managment LCA resultsvarywithchange in boundryconditionthereforeno robust conclusioncan be made Time consuming, require skill thereforecannot be easily used by thedecision makers Lackof universal standards for assessmentof wastewater treatment

26. Conclusions Whatcan LCA do? Avoidenvironmental problem shifting Is a powerfull tool to ensureenvironmentalsustainability of wastewater management Can be used to optimize system design What it cannot do? Ensure economic and socio-culturalsustainabilliy Whatwecan do? Combine LCA withlifecyclecostanalysis Ensure thatthetechnologyweselect is socio-culturallyacceptable Keep in mind! Uncertainity in the data used for LCA

27. Lo Manthang, Upper Mustang, NEPAL Thank you Thankyou Photo- Martina Karli