1 / 25

Brown Grease to Biogas at WWTPs

Brown Grease to Biogas at WWTPs. Puget Sound Brown Grease Symposium April, 2009. Presentation Snapshot. Business Case (why FOG to Biogas?) Case Study: Millbrae, CA Data from first 12 months of operation Reduced solids production ~30% weight reduction Improved solids dewaterability

lyle-holman
Download Presentation

Brown Grease to Biogas at WWTPs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Brown Grease to Biogas at WWTPs Puget Sound Brown Grease Symposium April, 2009

  2. Presentation Snapshot • Business Case (why FOG to Biogas?) • Case Study: Millbrae, CA • Data from first 12 months of operation • Reduced solids production • ~30% weight reduction • Improved solids dewaterability • Increase cake density, reduced polymer usage • Electricity production • Digester stability • Project Costs • Other Opportunities

  3. Business Case: Why do it? • Reduce operating costs • Reduce waste to landfill (diversion) • To capitalize on “Green” aspects of project (gain prestige) • To help diversify local utility’s renewable portfolio • “Greener” replacement for composting operation

  4. Business Case: How does it help me? • Can reduce demand for outside energy source (i.e. electricity, natural gas) • Can reduce solids being hauled from plant • Can increase waste diverted from landfills • Can create a revenue stream (tipping fees) • Can reduce carbon foot print of facility • Can provide good PR opportunities “The project here in Millbrae is cutting edge,” US Rep. Tom Lantos said. “It will allow us to develop energy independently and provide energy with resources we have not looked at in the past.” San Mateo Daily Journal, 8/31/2007

  5. Business Case: What do we do? • Anaerobic Digester Upgrade (typically) • Add Gas Conditioning Equipment • Add Cogeneration Equipment (or other gas utilization technology) • Add Waste Receiving Station

  6. Business Case: What if I do nothing? • Continue to “lose” money on missed opportunity • May miss funding opportunities • Waste streams may go to other facilities • Cost to do project will increase • Flared gas will be viewed as wasted opportunity

  7. Project Background

  8. Project Background & Update • 2004 project planning started • January 2007 Grease receiving started • September 2008 1 million gallons received

  9. Millbrae WPCP

  10. Tank vent Forced air ventilation system with soil bed odor scrubber Enclosed 12,000 gallon polyethylene pre-fabricated tank with level sensor. 300 gpm chopper pump for tank mixing From Truck Loading Ramp Tank drain 25 gpm progressive cavity pump with variable speed drive 200 gpm progressive cavity pump Heated sludge circulation loop

  11. Project Details • Will receive ~3000 gallons per day • Grease content = ~10% - 20% • Volatile solids destruction = 60% - 65% • Gas production = 15 CF/lb VS destroyed • Methane Content = 60% - 65% • Cost of electricity = $0.138/kWh • Tipping Fees: • $0.06 per gallon (negotiated with hauler)

  12. Reduced Solids Production

  13. Reduced Solids Production

  14. Reduced Solids Production

  15. Improved Dewaterability

  16. FY 06-07 Utility vs Cogen Production No grease received, 150,000 July 13 through August 2, 2007 125,000 100,000 kWh Started receiving grease 75,000 Januaruy 18, 2007 50,000 25,000 0 Feb-07 Jul-06 Jul-07 Nov-06 Apr-07 Dec-06 Jun-07 Sep-06 Oct-06 Jan-07 Sep-07 Mar-07 May-07 Aug-06 Aug-07 Month PG&E Co-Gen Power Production

  17. Digester Stability

  18. How much did it cost? • Total project cost ~$5.5 M • Base cogen facility ~$1.9 M • Switchgear upgrade ~$0.7 M • Grease receiving station ~$0.7 M • CNG storage facility ~$0.7 M • Digester mixing ~$1.5 M

  19. Opportunities Note: This list is also broken down by state

  20. Opportunities in WA Source: 2004 Clean Watersheds Needs Survey

  21. Opportunities in OR Source: 2004 Clean Watersheds Needs Survey

  22. Thank You • Greg Chung • gregchung@kennedyjenks.com • Richard York • (former plant superintendant) • Joseph Magner • jmagner@ci.millbrae.ca.us

More Related