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Water/Wastewater Treatment and Sustainability. Dr. Zuzana Bohrerova Ohio Water Resources Center Civil, Environmental and Geodetic Engineering. Water Sustainability. What is sustainability?
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Water/Wastewater Treatment and Sustainability Dr. ZuzanaBohrerova Ohio Water Resources Center Civil, Environmental and Geodetic Engineering
Water Sustainability What is sustainability? Conference on Sustainable Development 2012 (Rio+20): Water is “at the core of sustainable development as it is closely linked to a number of key global challenges”
Water Sustainability SOURCE: UN water.org, 2013 Triple bottom line approach to sustainability: ENVIRONMENTAL ECONOMIC SOCIETAL
Water Sustainability • Are we using water in sustainable manner?
Water Footprint SOURCE: UN water.org, 2013 • http://www.waterfootprint.org/?page=files/productgallery
Water Scarcity • 41% of the world’s population lives in river basins suffering from moderate to high water stress
Water Quality SOURCE: UN water.org, 2013
Achieving Sustainability Goals (UN) • TARGETS (draft, after 2015) • Universal access to safe drinking water, sanitation and hygiene • Improve by x% the sustainable use an development of water resources in all countries • All countries strengthen equitable, participatory and accountable water governance • Reduce untreated wastewater by x%, nutrient pollution by y% and increase wastewater reuse by z% • Reduce mortality by x% and economic loss by y% from natural and human-induced water-related disasters
Significance of Water Resources – U.S. perspective Drinking water in US is among the best in the world, BUT • Emerging contaminants threaten our water supplies • Microcystin, Perchlorate, Arsenic, PHACs • Development in arid, coastal regions • Many waters are not “fishable and swimmable” • Water/wastewater infrastructure security • Water x Energy Nexus issues
Current Urban Water Cycle Groundwater or surface water inputs(Q) • Linear centralized treatment system based on disposal 5% Q Waste sludge, brine (to disposal) WTP Loss to leakage(33%Q) City DistributionSystem Outfall57-66% Q 5% Q WWTP Waste sludge, brine (to disposal)
Current Urban Water Cycle • Current urban wastewater management is linear treatment system based on disposal • Abuse of water for diluting human excreta • High cost for running and operating current systems • Collection infrastructure and fast development • Need of sustainable, closed-loop urban wastewater management system based on conservation of water and nutrients
Approach to Water Infrastructure Nelson, Sustainable Water Infrastructure
Water Energy Nexus • Water and energy systems are interdependent SOURCE: DOE, energy.gov, 2014
Electricity Use for Water/Wastewater Treatment in US • Uses 4% of nation’s electricity • Majority for moving water/wastewater (80%), rest treating • Groundwater supply as water source requires 30% more electricity (versus surface water) • Increases in energy consumption: • Age of delivery systems (friction increase, efficiency decrease) • Conservation (systems will operate on below minimum level; trend to smaller system; economies of scale) • Improve treatment requirements • Advanced wastewater treatment 3x more electricity than trickling system
Drinking water treatment • EPRI
Some more sustainable WWT technologies- developing world • Lagoons/wetlands • Climate • Land • Reuse potential? • Anaerobic digesters (USAB) • Small and large scale • Biogas production and stable humus • Operation • SAT (Soil Aquifer Treatment) technologies • Partially treated effluent used for recharge (Gaza) • Breaks pipe-to-pipe connection • Could lower WQ of groundwater
Evaluation Sustainability of WWTP Muga and Mihelcic, 2008, Journal of Env. Management, 88:437-447
Utility Services Leading Sustainability From US EPA: • Alternative fuels • Automation • Resource recovery • Resiliency • Customer engagement – conservation • Investment in capital facility maintenance
Water Reuse • Not the only solution • Needs to be combined with: • water conservation • alternative water supply • green infrastructure • development in treatment technologies • environmental restoration
Water Quality Change • Electricity consumption decreases sustainability of water reuse (LCA)
Water Reuse for Irrigation • Most reclaimed water contain TDS – salts • Irrigation needs to be evaluated for long term sustainability of soil resources • Salt accumulation in soils – change in root osmosis and ability to grow (uptake nutrients and water) • Israel about 70% reuse water used for irrigation – salinity problem. • Strict source control (what is discharged into wastewater) • Changes in water softening agents and detergents • Emerging contaminants
Domestic Water Reuse – dual reticulation Water corporation, Australia, published online
Reverse Osmosis Future development: better membranes, lower energy requirements
San Diego toilet to tap • Facility available and treating wastewater • Regulations not in place • Public oppose direct potable use, but willing to use as indirect potable use http://www.sandiego.gov/water/purewater/demo/index.shtml
Toilet to tap feasible – biggest hurdle is publicperception Scientific American, CREDIT: Sam Kaplan; STYLING BY LINDA KEIL Halley Resources
Blue Print Columbus • Sanitary sewer overflows has to be eliminated • Solution • Green infrastructure • OARS deep sewer tunnel http://www.youtube.com/watch?v=do6jFv_HdbE&feature=youtu.be
References • Kennedy, L. and Tsuchihashi, R. (2005), “Is Water Reuse Sustainable? Factors Affecting its Sustainability. TheArabian Journal for Science and Engineering, 30(2C), 3-15 • Jhansi, S.C. and Mishra, S.K. (2013), “Wastewater Treatment and Reuse: Sustainable Options”, Consilience: The Journal of Sustainable Development, 10(1), 1-15