This document provides an overview of municipal and domestic wastewater treatment processes. It discusses the key microbial processes involved, including biodegradation, bioconversion, and removal/separation processes. Common treatment steps like primary settling, biological treatment, clarification and disinfection are outlined. Specific examples of wastewater treatment plants and processes, such as activated sludge reactors and anaerobic digestion, are also described. The document raises questions around optimizing microbial functions in wastewater treatment and recovering resources from wastewater.

1. Municipal and Domestic Wastewater Treatment The Largest Biotechnology Industry in the World … … and the least understood?

2. Veolia Water N° 1 worldwide for water services; revenue of €12.5 billion for 2008; providing drinking water and wastewater treatment services to more than 139 million people around the world; 93,433 employees; Permanent operations in 64 countries ; Managing close to 4,400 contracts around the world.

3. 62,000 employees serving 68 million people worldwide with drinking water 44 million people for wastewater services 46 million people for waste collection service Revenues of $18.4 billion in 2007 An R&D budget of $95 million for water research

4. Wastewater is the biggest waste by volume in New Zealand. Approximately 1.5 billion litres of domestic wastewater is discharged into the environment daily.

5. Wastewater in Auckland: Watercare wastewater from about 800,000 people industrial customers equivalent of 370,000 people. 290,000 cubic metres of wastewater each day. North Shore City WTP serves 199,000 people Other plants in Pukekoe,Waiuku, Beachlands, Kumeu, Orewa, Warkworth, Helensville, Waiheke Cleavdon, on site treatment all rural properties

6. What is wastewater? (aka Sewage) Water (99%) Organics Nutrients Toxic materials Infectious agents Plus??

7. Henry and Heinke 1989 Environmental science and engineering, Prentice Hall p416 http://www.earthwise.dep.state.pa.us/content/knowledgedocs/pdf/WastewaterCompositionComparisons.pdf Faecal coliform Bacteria (MPN/100ml x106) 50 60 100 Copper (mg/l) 0.14 0.17 0.21 Chromium 0.003 0.01 0.016 Cadmium 0.04 0.08 0.16 Nickel 0.01 0.06 0.11 Lead 0.05 0.1 0.2 Zinc 0.19 0.29 0.38

8. Waste product for treatment and disposal? or Resource to recover and use? Discussion

9. What should waste treatment achieve? What are the microbiological processes that can be coopted? Control strategies to optimise the microbial function. Wastewater treatment

10. What should waste treatment achieve? Recover Materials and Energy Remove or Reduce Environmental and Human Health Risk Priorities for reduce or remove Safely Dispose of Residue Wastewater treatment

11. What are the microbiological processes that can be coopted? Biodegradation - Bioconversion Removal/separation – flocculation attachment to surfaces Inactivation, lysis

12. Microbial Processes and Influences Biodegradation biomass + energy+ residual Biodegradation requires degrading organisms and supporting assemblage (enzymes and cofactors) Amenable contaminant - physical and chemical state contact between MO and contaminant environment - Temp, pH, Oxygen, Nutrients limiting substances, ionic strength. r elative proportions of components Bioconversion Removal Inactivation

13. Microbial Processes and Influences Biodegradation Bioconversion Incomplete biodegradation degrading organisms and supporting assemblage (enzymes and cofactors) Amenable contaminant - physical and chemical state contact between MO and contaminant environment - Temp, pH, Oxygen, Nutrients limiting substances, ionic strength. r elative proportions of components Removal Inactivation

14. Microbial Processes and Influences Biodegradation Bioconversion Removal adsorption, attachment, incorporation and deposition or separation (specific or non-specific) Inactivation Degradation, starvation, stress,

15. Biological wastewater treatment and processes directed at biological components Eg Activated sludge Fixed growth reactor Suspended media reactor Aerated ditch Oxidation pond Constructed wetland Anaerobic digestion Eg disinfection Oxidation ponds

16. Typical treatment train Settlement Biological treatment Clarification Disinfection Discharge Inflow Remove solids and fats Reduce carbon and nutrients Remove biological solids Reduce pathogens

17. Mangere Wastewater Treatment Plant current Screening Earth Filter clarification Activated sludge Sludge Primary Settling CH 4 gas Anaerobic Digester Dewatering Landfill Effluent Discharge Disinfection: Anthracite filter and UV odor

18. Mangere Wastewater treatment plant:

19. Activated sludge Reactors/Clarifier

20. Activated sludge Reactors/Clarifier Objective: Reduce solids, BOD, COD, Nitrogen, fats and oils in liquid flow Mechanism: Enhancement of microbial activity to induce floc formation and settlement and remove contaminants to sludge biodegradation POC+ DOC+N Biomass Sorption of other contaminant eg metals, HC Stirring and aeration Microbiological players bacteria community dominated by facultative organotrophic bacteria. eg Pseudomonas , F la v obacterium Achromobacter , M icroco c cus , B acillus , Acinetobacter Filementous bacteria eg Nocardia, Zooglea, Thiothrix, Nostocoida, Microthrix, Sphearotilus yeasts and moulds to a lesser extent Protozoa, rotifers. worms Extracellular polymer linkers forming flocs of settlable density

21. Sludge treatment – biogas production

22. Nitrogen removal Why remove nitrogen? Where does nitrogen come from? What is the form of nitrogen in wastewater?

23. Classical N cycle Ahn Y-H. Process Biochem 42 2006 p 1709 - 1721

24. Nitrogen removal N = approx 12 % of cell mass N mostly removed -through cell removal Nitrification - chemoautotrophic bacteria Slow growing 10 + days sludge age NH 4 + + 2O 2 NO 3 - + 2H + +H 2 O Nitrosomonas, Arthrobacter , ? 3NH 4 + + 3O 2 2NO 2 - + 4H + +2H 2 O Nitrobacter , Arthrobacter ? 2NO 2 - + O 2 2NO 3 - Denitrification – eg Pseudomonads, Thiobacillus denitrificans C 6 H 12 O 6 + 4NO 3 - 6CO 2 + 6H 2 O + 2N 2 NO 3 - NO 2 - NO N 2 O N 2

25. Anaerobic ammonium oxidation (anammox) Ahn Y-H. Process Biochem 42 2006 p 1709 - 1721

26. Anammox Anammox "anaerobic ammonium oxidation". The anammox reaction is : NH4+ + NO2- = N2 + 2H2O + energy This reaction is carried out by a group of planctomycete bacteria. Two of those have been named provisionally: Candidatus "Brocadia anammoxidans" and Candidatus "Kuenenia stuttgartiensis". http://www.anammox.com/research.

27. Nitrite reductase Hydrizine hydrolase Hydrazine dehydrogenase http://www.anammox.com/anammox_mechanism.html Last updated: March 9, 2004

28. Anommox Application http://www.anammox.com/application.html wastewater streams high in ammonium (>0.2 g/l) and low in organic carbon (C:N ratio lower than 0.15). The two processes proceed as follows: partial nitrification 2NH 4 + + 1.5O 2 =NH 4 + + NO 2 - + H 2 O + 2H + anammox NH 4 + + NO 2 - =N 2 + 2H 2 O total 2NH 4 + + 1.5O 2 =N 2 + 3H 2 O + 2H + Requires: 50% less oxygen. May reduce operational costs by 90%, decrease in CO 2 emissions of more than 100%

29. Nitrosomonas aerobic denitrification Ahn Y-H. Process Biochem 42 2006 p 1709 - 1721

30. Overall Nitrogen web Ahn Y-H. Process Biochem 42 2006 p 1709 - 1721

31. What happens to Nitrogen at Mangere WTP

33. Assignment: Mangere Complex adds NZ$1b to Auckland City Economy. The just completed upgrade of the Mangere Materials Complex adds the final process to allow complete recovery of the materials from what was once called wastewater. The wastewater also called sewage was collected at the plant and partly treated before being tipped into the Manukau harbour. The cost of this treatment both in $ terms and in environmental cost was in excess on $50 m in 2010. Recovery of the resources that was once waste and the industries linked to them are now worth over $1 b. The most notable successes have been…. NZ Herald May 12 2025

34. Assignment: the to do.. Complete the next 10 paragraphs of the Newspaper Article (5%) plus 2 page document in point form that provides more information and some ideas on the approach to reclamation of resources (with references) (10%) Due date: Monday May 31st Submit to SRC by 4 pm Value 15% of final mark

35. Field Visit : Wednesday 19 May Mangere Wastewater treatment plant Leave outside SBS at 11.00 am sharp Closed in shoes – no Sandals or Jandals Objectives To understand the treatment process To identify the strengths and weaknesses of the process and the main constraints on treatment and disposal of waste Identify the pressures on the process to perform effectively Identify areas where there is opportunity for improvement or benefit. Own Transport?

36. Older reviews: Ahn Y-H Sustainable nitrogen elimination biotechnologies: A Review. Process Biochemistry 41, 2006, 1709 - 1721 Mendoza-Espinosa, Leopoldo Stephenson, Tom. A review of biological aerated filters (BAFs) for wastewater treatment Environmental Engineering Science. 16(3). 1999. 201-216. Stratful, I.; Brett, S. Scrimshaw, M. B.; Lester, J. N.. Biological phosphorus removal, its role in phosphorus recycling Environmental Technology. 20(7). July, 1999. 681-695. Grady, C. P. L., Jr. Filipe, C. D. M. . Ecological engineering of bioreactors for wastewater treatment Water, Air, & Soil Pollution. 123(1-4). October, 2000. 117-132 de-Bashan, Luz E.; Bashan, Yoav Recent advances in removing phosphorus from wastewater and its future use as fertilizer (1997-2003) Water Research. 38(19). November 2004. 4222-4246. Mallick, Nirupama. Biotechnological potential of immobilized algae for wastewater N, P and metal removal: A review. BioMetals. 15(4). December 2002. 377-390. Low, Euan W.; Chase, Howard A.. Reducing production of excess biomass during wastewater treatment Water Research. 33(5). April, 1999. 1119-1132. Aksu, Zumriye. Application of biosorption for the removal of organic pollutants: A review Process Biochemistry. 40(3-4). March 2005. 997-1026. Lazarova, V. ; Savoye, P. Janex, M. L.; Blatchley, E. R., III Pommepuy, M. [Author]. Advanced wastewater disinfection technologies: State of the art and perspectives Water Science & Technology. 40(4-5). Aug.-Sept., 1999. 203-213. Chuichulcherm, S.. An integrated system for the bioremediation of wastewater containing xenobiotics and toxic metals Engineering in Life Sciences. 4(4). August 2004. 354-357. Books that contain helpful sections ( not on close reserve) Fry et al : 1992 Microbial control of pollution: Society for General Microbiology. Gray NF 2004 :Biology of wastewater treatment 2nd ed. Imperial College Press, London. Gerardi M and Zimmerman M :2004 Wastewater Pathogens: Electronic reproduction Somerset, New Jersey : Wiley InterScience, [electronic resource]

37. Suggested Reading Ekama George A [a]; Wentzel Mark C [a]. Difficulties and developments in biological nutrient removal technology and modelling. Water Science & Technology. 39(6). March, 1999. 1-11. ( try via science direct) Fuerhacker M; Bauer H; Ellinger R; Sree U; Schmid H; Zibuschka F; Puxbaum H. Approach for a novel control strategy for simultaneous nitrification/ denitrification in activated sludge reactors. Water Research. 34(9). June, 2000. 2499-2506 Strous Marc; Van Gerven Eric; Zheng Ping; Kuenen J Gijs; Jetten Mike S M [a]. Ammonium removal from concentrated waste streams with the anaerobic ammonium oxidation (Anammox) process in different reactor configurations. Water Research. 31(8). 1997. 1955-1962 Krumins Valdis; Hummerick Mary; Levine Lanfang; Strayer Richard; Adams Jennifer L; Bauer Jan. Effect of hydraulic retention time on inorganic nutrient recovery and biodegradable organics removal in a biofilm reactor treating plant biomass leachate. Bioresource Technology 85. December, 2002. 243-248.