The Wastewater Treatment Plant of the Future. Robert K. Bastian Office of Wastewater Management Washington, D.C.

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1 The Wastewater Treatment Plant of the Future Robert K. Bastian Office of Wastewater Management Washington, D.C.

2 Key Areas Facing POTWs in the Future Nutrient Controls/Recovery Contaminants of Emerging Concern Improved Energy Efficiency and Efforts to Make POTWs Energy Self Sufficient, Reduce GHG Emissions/Reduce Carbon Footprint Expanded Water Reuse, and Use of Graywater and Stormwater as Alternative Water Supply Sources By-Product Production Multi-purpose Projects Climate Change Accommodations 2

3 Nutrient Controls. Over half of the receiving waters are impaired by excess nutrients Tighter nutrient discharge limits, TMDL load allocations, trading opportunities Nutrient recovery (e.g., Struvite) and marketing opportunities 3

4 An Urgent Call to Action - Report of the State-EPA Nutrient Innovations Task Group, August 2009

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6 An Urgent Call to Action - Report of the State-EPA Nutrient Innovations Task Group, August 2009

7 An Urgent Call to Action - Report of the State-EPA Nutrient Innovations Task Group, August 2009

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9 Struvite (magnesium ammonium phosphate) recovery Ostara, Multiform Harvest, NuReSys, Phospaq, Crystalactor

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11 Contaminants of Emerging Concern (CECs). Potentially cause deleterious effects in aquatic life at environmentally relevant concentrations; may be candidates for future regulation depending on their (eco)toxicity, potential health effects, public perception, and frequency of occurrence in environmental media. o Widespread uses o Some indication of chemical persistence o Effects found in natural systems o Public concerns What s Good for the Fish is Good for us Also 11

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13 Persistent organic pollutants (POPs) such as polybrominated diphenyl ethers (PBDEs; used in flame retardants, furniture foam, plastics, etc.) and other global organic contaminants such as perfluorinated organic acids; Pharmaceuticals and personal care products (PPCPs), including a wide suite of human prescribed drugs (e.g., antidepressants, blood pressure), over-thecounter medications (e.g., ibuprofen), bactericides (e.g., triclosan), sunscreens, synthetic musks; Veterinary medicines such as antimicrobials, antibiotics, anti-fungals, growth promoters and hormones; Endocrine-disrupting chemicals (EDCs), including synthetic estrogens (e.g., 17α-ethynylestradiol, which also is a PCPP) and androgens (e.g., trenbolone, a veterinary drug), naturally occurring estrogens (e.g.,17ß-estradiol, testosterone), as well as many others (e.g., organochlorine pesticides, alkylphenols) capable of modulating normal hormonal functions and steroidal synthesis in aquatic organisms; Nanomaterials such as carbon nanotubes or nano-scale particulate titanium dioxide, of which little is known about either their environmental fate or effects. 13

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15 A USGS reconnaissance report issued in 2002 documented the occurrence of organic wastewater contaminants (OWCs) being released into surface waters from POTWs. The targeted OWCs included PPCPs, veterinary medicines and other EDCs. The investigators found at least one of 95 different target OWCs in 80 percent of the 139 streams sampled. A median of seven, and as many as 38, OWCs were found in single samples.

16 Improved Energy Efficiency and Efforts to Make POTWs Energy Self Sufficient, Reduce GHG Emissions/Reduce Carbon Footprint Electric use by POTWs - $4 billion annually, 25-30% of total plant O&M Cost Energy Conservation at POTWs can result in significant energy savings (10-50%, depends on plant equipment & processes) through: - Process optimization (e.g. lower dissolved oxygen, blower control, electric load shifting) - Equipment modifications (e.g. energy efficient blowers, fine bubble diffusers, VFDs, efficient pumps, digester & building heating, electricity generation) - Solids handling and disposal practices (e.g. land application, composting) 16

17 Estimated US GHG Emissions (2006) from electricity generation for centralized W&WW treatment 69.8 Tg CO 2 eq. (1.2% of total US GHG emissions) Significant energy savings from POTW anaerobic digester gas utilization for combined heat and power (CHP) MW of clean electricity generation if all 544 facilities >5 mgd that use anaerobic digestion install CHP Energy conservation will become increasingly significant due to: - Increased population, climate change, water scarcity, aging infrastructure, costs Energy self-sufficiency can be implemented in the US; requires focus on overcoming barriers. A few US plants are on their way. 17

18 Energy Used in Wastewater Treatment Aeration - 52 % Misc. - 3% Pumping - 12 % RAS pumping - 3 % Sludge processing - 30% Figures shown are typical for activated sludge plants. 18

19 Of the more than 1,200 POTWs in the U.S. that employ anaerobic digesters and produce biogas utilize biogas for energy generate electricity from biogas deliver electricity to the grid send biogas to pipelines import waste to their digester flare gas Percentage of installed power generation technologies Facilities with operating anaerobic digestion. Percentage of biogas utilization technologies (some facilities use more than one)

20 Combustion Turbine New-Generation Lean Burn Cogeneration Engine Cummins Power Generation Steam Turbine Microturbine Molten Carbonate Fuel Cell 20

21 Portfolio Manager

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26 Expanded Water Reuse, and Use of Graywater and Stormwater as Alternative Water Supply Sources Projected Water Reuse 2001 to Billion Gallons per Day (bgd) 26

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28 Irrigated w/wastewater for nutrient removal, crops harvested and used for food, animal feed, energy feedstock, etc.

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31 GWR System (OCWD and OCSD) Advanced Water Treatment Flow Diagram Enhanced Source Control Secondary Treatment 86 mgd Microfiltration (MF) 70 mgd 70 mgd Reverse Osmosis (RO) Ultraviolet Light (AOP) Purified Water OCSD Secondary Effluent Backwash OCSD Plant 1 Brine OCSD Outfall with hydrogen peroxide Natural soil filtration

32 Most recent WSTB/NRC/NAS study on Water Reuse Water Reuse: Potential for Expanding the Nation's Water Supply through Reuse of Municipal Wastewater (2012) Final Report Understanding Water Reuse: Potential for Expanding the Nation's Water Supply Through Reuse of Municipal Wastewater Booklet

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34 Green Infrastructure

35 Green Infrastructure

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38 By-Product Production 38

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43 Commercial Slow-Release Granular Fertilizer Production Unity Envirotech s granulation process VitAG s ammonium mix process

44 Bioplastic resin used in the production of polyhydroxyalkanoates bio-degradable, renewably-derived plastics.

45 Multi-purpose Projects. e.g., Sustainable Natural Systems for treatment and reuse practices Modern Sustainable Natural Systems involve land application practices optimized for treatment and reuse while protecting the environment and/or use of conventional irrigation procedures and historically accepted practices for recycling animal manure back to the land Land treatment and reuse of municipal & industrial effluents Wetlands treatment and reuse of effluents, stormwater Green infrastructure for the treatment of stormwater 45

46 Well documented, long-term demo projects Penn State, PA 516 ac forest and old fields; spray irrigation Muskegon Co., MI 10,400 ac cropland; center pivots Lubbock, TX 4,000 ac land treatment; leaseback to farmer Clayton Co., GA 4,000+ ac forest land; recent conversion to constructed wetlands Bakersfield, CA 2,400 ac cropland irrigation; leaseback Toole, UT 1,200 ac cropland, cash lease for water sale to farmer Overland Flow Systems Hanover, NH; Easley, SC; Ada, OK; Davis, CA SAT Systems Ft. Devens, MA; Vineland, NJ; Lake George, NY; Calumet, MI; Brookings, SD; Boulder, CO, Phoenix, AZ; Hollister, CA

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56 Floating Wetlands, Restorers

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58 Algal Turf Scrubbers

59 Climate Change Accommodations Potentially linked to energy use and renewable energy, but also issues for coastal areas due to inundation concerns (e.g. Hurricanes Katrina and Sandy) as well as POTWs elsewhere due to severe weather impacts. Facility protection from flooding, inundation, etc. Greenhouse Gas Mitigation Strategies - Improved energy efficiency & energy generation at wastewater facilities - Water conservation and water reuse - Green infrastructure and low impact development - Carbon sequestration 59

60 Source: NASA Earth Observatory, based on IPCC Fourth Assessment Report (2007) Warmer water Source: NOAA, Increases in tropical storm intensity Source: Maps of Lands Vulnerable to Sea Level Rise as found in EPA 2008u Sea level rise Precipitation changes Ocean and coastal changes