Wastewater Treatment or Resource Recovery:
Maximizing the Energy Potential of Your Infrastructure
Angela Hedgecock, PE, CEM, LEED APSiemens Industry, Inc.
Presentation Outline
• Overview of Energy Use for Wastewater Treatment• Opportunities to Reduce Operating Cost• Wastewater Infrastructure as a Resource• Energy Savings Performance Contracting• Questions
10-3-12 Net Zero through Emerging Technologies 2
Overview of Sector-wide Energy Use
10-3-12 Net Zero through Emerging Technologies 3
Facility Energy Use 1
10-3-12 Net Zero through Emerging Technologies 4
• Biological Aeration 39%• Aerobic Digestion 35%• Pumping 14%• Lighting / Buildings 6%• Thickening / Dewatering 3%• Clarifiers 2%• Headworks 1%• Chlorination <1%
1 Water Environment Federation MOP 32 Energy Conservation in Water and Wastewater Facilities 2009. Appendix C Table C.2. Activated Sludge WWTP – 5 MGD.
Total Operating Cost
10-3-12
Net Zero through Emerging Technologies 5
Energy
Staffing
Solids
ChemicalsMaintenance
40%
30%
10%
15%5%
10-3-12
6
• Energy Efficiency Aeration or mixing upgrades (blowers, diffusers, controls) Pumping system upgrades (pumps, VFDs, controls) Biological process improvements/modifications Improved ultraviolet disinfection system controls Motor replacement, ventilation, lighting
• Solids Thickening, Dewatering, and Disposal Improvements to dewatering or thickening Mechanical dewatering or drying Improved digestion (aerobic or anaerobic) Alternative solids destruction processes
• Chemical Savings Conversion to biological phosphorus removal Optimized chemical feed system operation Odor control system replacement
Typical Cost Savings Opportunities
Net Zero through Emerging Technologies 610-3-12
7
Conventional Approach to Waste Management
Net Zero through Emerging Technologies 710-3-12
Pumping Wet Stream Treatment
SolidsSolids Handling and Dewatering
Surface Water/ Groundwater
Wastewater Collection
Landfill
Effluent
Solids
Municipal Solid Waste (MSW)
8
Anaerobic Digestion Provides Benefit
Net Zero through Emerging Technologies 810-3-12
Pumping Wet Stream Treatment
SolidsAnaerobic Digestion
Surface Water/ Groundwater
Wastewater Collection
Landfill
Effluent
Reduced Solids
Biogas for Beneficial Reuse:-Digester Heating-Cogeneration-Sludge Drying
9
Hauled Wastes Improve Feasibility for Small Plants
Net Zero through Emerging Technologies 910-3-12
Pumping Wet Stream Treatment
SolidsAnaerobic Digestion
Surface Water/ Groundwater
Wastewater Collection
Landfill
Effluent
Increased Biogas Production
Hauled Wastes:-FOG-High Strength Wastes
Improved FOG Control
Potential Revenue through Tipping Fees
10
Co-digestion Provides Further Benefit
Net Zero through Emerging Technologies 1010-3-12
Pumping Wet Stream Treatment
SolidsAnaerobic Digestion
Surface Water/ Groundwater
Wastewater Collection
Landfill
Effluent
Further Increase to Biogas Production
Food Waste
Reduced Organics in MSW
Potential Increased Revenue through Tipping Fees
11Net Zero through Emerging Technologies 1110-3-12
• Holistic approach to waste management can create additional opportunities
• Hauled wastes and food wastes can make anaerobic digestion and biogas recovery feasible for smaller facilities
• Military installations have the ability to effectively control waste streams and implement co-digestion
• Newer technology allows digestion of higher solids waste streams providing greater flexibility and opportunity
• The ability to generate renewable electricity on-site helps meet both energy efficiency and energy security objectives
Benefits of “Re-thinking” Waste Management
12Net Zero through Emerging Technologies 1210-3-12
• Additional opportunities exist when drinking water infrastructure is also considered:• Energy efficiency and process optimization improvements can
reduce operating costs
• Water conservation measures can result in the need to produce less drinking water and treat less wastewater
• Improved metering and optimized treated water recovery can help limit unaccounted for water use and improve revenue generation
• Wastewater effluent reuse and sewer mining may create additional water sources for non-potable uses
Going Beyond Waste Management
13Net Zero through Emerging Technologies 1310-3-12
Energy Savings Performance Contracts
• Energy and Security Goals require action now
• Energy Savings Performance Contracts (ESPCs) offer a way to leverage future guaranteed savings to finance projects today
• Approaching initiatives (energy management, water conservation, waste management and security) in a comprehensive manner may yield additional opportunities and allow more dramatic improvements to be realized
14Net Zero through Emerging Technologies 1410-3-12
Angela HedgecockPE, CEM, LEED AP
Siemens Industry, Inc.Building Technologies Division
Alternative Energy Group, Project Developer
Direct: (863) 937-6726
Fax: (866) 889-6403
Cell: (863) 512-1950