The URL can be used to link to this page

Home My WebLink About06.b. Receive update on the Membrane Pilot Project Page 1 of 9 Item 6.b. CENTRAL SAN December 14, 2020 TO: REAL ESTATE, ENVIRONMENTAL AND PLANNING COMMITTEE FROM: AMANDA CAUBLE, ASSOCIATE ENGINEER REVIEWED BY: DAN FROST, SENIOR ENGINEER DANEA GEMMELL, PLANNING AND DEVELOPMENT SERVICES DIVISION MANAGER JEAN-MARC PETIT, DIRECTOR OF ENGINEERINGAND TECHNICAL SERVICES ROGER S. BAILEY, GENERAL MANAGER SUBJECT: RECEIVE UPDATE ON THE MEMBRANE PILOT PROJECT Staff will provide an update on the Membrane Pilot Project (Pilot Project)for discussion and Committee feedback. Background and Pilot Project Updates I n January 2020, staff introduced the Pilot Project to demonstrate membranes as a technology for tertiary filtration at Central San to produce recycled water. A goal of the Pilot Project was to operate a pilot unit and evaluate the feasibility of tertiary membrane filtration prior to bidding the Filter Plant and Clearwell Improvements Project (Filter Project) Phase 1 A, District Project (DP) 7361, which included a bid alternate for renovating one of the existing dual granular media filters currently used for recycled water production. Due to the timeline needed to complete the Pilot Project and the Filter Project bidding schedule, focus shifted to prepare a Business Case Evaluation (BCE)to compare granular media filtration with ultrafiltration membranes. Completed in August 2020, the BCE compared the current plan of renovating existing granular media filters to an ultrafiltration membrane system for Title 22 recycled water production. Central San received planning-level proposals from four membrane manufacturers who used plant water quality data to determine the number of membrane modules and associated costs. To account for the secondary effluent water quality that would be supplied to the membranes, most of the manufacturers were conservative in operating flux rates, thus needing more membrane modules, and increasing estimated capital and operating costs. The 30-year life cycle cost to serve buildout demands for Title 22 recycled water customers using tertiary pressure membranes was comparable to granular media filtration if a filter pretreatment process will be required to increase the existing filter plant capacity. After construction of Filter Project, Phase 1 A is complete, the single renovated filter will undergo demonstration testing to confirm whether design capacity of the renovated filter(i.e. 2 gallons per minute per square foot) is met through filter polymer and operational optimizations. If it is not met, a filter pretreatment system would be needed to serve buildout demands. Staff believe that continuing the Pilot December 14, 2020 REEP Committee Meeting Agenda Packet- Page 22 of 33 Page 2 of 9 Project concurrently with the Filter Project will provide valuable data to make informed decisions on whether to continue to renovate the remaining granular media filters or move forward with membrane filtration. Tertiary Membrane and Reverse Osmosis Pilot Staff is working with Carollo Engineers, I nc. (Carollo)to supply a pilot system and assist with the Pilot Project. The 150-gallons per minute tertiary membrane pilot skid accommodates three membrane modules operating in parallel. Staff will evaluate multiple established manufacturers and refine operating parameters used in scaling up Capital and Operations and Maintenance costs for full-scale installation. If Central San chooses to continue with membrane filtration, other manufacturers not included in this Pilot Project could still be evaluated and considered.Attachments 1 and 2 illustrate the configuration and size of the membrane pilot unit. The Pilot Project will evaluate membrane performance, including flux rates, fouling rates and cleaning requirements, membrane feed water quality and temperature, backwash water quality, and treated permeate water quality such as turbidity, pH, total dissolved solids, ultraviolet transmissivity, and bacteria and virus removal.A dual-stage reverse osmosis skid will also be piloted to better inform the viability of membranes as pre-treatment, and for potential future advanced recycled water opportunities, such as the Water Exchange Project, DP 7368. Pilot Project Budget and Financial Impact The Pilot Project will be funded from the Applied Research and Innovations Project, DP 7315, and does not require additional budget. The membrane pilot system will be provided by Carollo is anticipated to be around $114,000, and the total estimated budget for the Pilot Project is approximately$550,000 to $600,000. • Pilot Installation: The cost to install and connect the membrane filtration pilot system at Central San is expected to be within staff authority limits. Staff will either contract the work through a change order with an existing Central San contractor or, depending on cost and schedule considerations, will bid the work through the Uniform Public Construction Cost Accounting Act(UPCCAA) process. • Consultant On-Call Support: Central San staff will issue task orders through an existing on-call engineering consultant support agreement to provide specialized expertise and assistance for preparing the pilot operating and testing plan, provide quality assurance for data gathering, evaluate pilot performance, and assist with pilot inter-connection. • Staff Support and Testing: Central San staff (approximately 0.5 to 1.0 full-time equivalent "FTE")will manage and conduct the Pilot Project, utilizing vendor and consultant support as described above. Staff will also perform water quality sampling and analyses and use outside laboratory agreements for analyses that cannot be completed by staff. Pilot Project Schedule The Pilot Project is anticipated to start in Winter 2020/2021 and operate for approximately four months. Results from the Pilot Project are anticipated in Summer 2021. Strategic Plan Tie-In GOAL TWO:Environmental Stewardship Strategy 1—Achieve 100%compliance in all regulations, Strategy 3—Support regional development of local water supply GOAL SIX.Innovation and Optimization Strategy 2—Improve and modernize operations through technology and efficiency measures December 14, 2020 REEP Committee Meeting Agenda Packet- Page 23 of 33 Page 3 of 9 ATTACHMENTS: 1. Pilot Isometric View 2. Pilot Example Photo 3. Presentation December 14, 2020 REEP Committee Meeting Agenda Packet- Page 24 of 33 Page i of • ISOMETRICATTACHMENT 1 : TERTIARY MEMBRANE PILOT � f � < � < t1� � • sem'• ►,1 I ��' i ISOMETRIC December 1 1 REEP Committee • Agenda Packet- '.•- 25 of Page 5 of 9 ATTACHMENT 2: EXAMPLE PHOTO OF TERTIARY MEMBRANE PILOT TW- *� wo , � l � P December 14, 2020 REEP Committee Meeting Agenda Packet- Page 26 of 33 Page 6 of 9 ATTACHMENT 3 UPDATE ON MEMBRANE PILOT PROJECT Jean-Marc Petit -� Director of Engineering and Technical Services Real Estate, Environmental, and Planning Committee December 14, 2020 I PROJECT OBJECTIVES 1 . Proof of concept using tertiary membrane filtration for producing Title 22 recycled water with Central San's secondary effluent 2. Evaluate multiple established membrane manufacturers and refine operating parameters 3. Pilot a dual-stage reverse osmosis skid to better inform the viability of membranes as pre-treatment and for potential future advanced recycled water opportunities December 14, 2020 REEP Committee Meeting Agenda Packet- Page 27 of 33 1 Page 7 of 9 PROJECT COST • Estimated project cost approximately $600,000 (including consultant support, pilot system, installation, and analyses) • Funded from existing budget through District Project 7315 — Applied Research AW z PROJECT SCHEDULE • October-November 2020: Identified piloting opportunity with Carollo Engineers, Inc. (Carollo) and established pilot parameters • December 2020: Plan to issue Task Order with Carollo to develop testing plan and site design • March-April 2021 : Site construction and pilot preparation • April 2021 : Approximate timing to receive Pilot Unit • April-August 2021 : Operate Pilot Unit l4 December 14, 2020 REEP Committee Meeting Agenda Packet- Page 28 of 33 2 ISOMETRIC OF : ' O REVERSE ISOMETRIC VIEW ISOMEYRIC VIEW �C'S CENTRAL SAN PHOTO • MEMBRANE r� 1 z Ai CFNTRAI SAN Page 9 of 9 QUESTIONS? Rum CFNTPAISAN < _ -= December 14, 2020 REEP Committee Meeting Agenda Packet- Page 30 of 33 4