Wet Weather and Advanced Treatment: Procurement Strategies to Secure the Right Technology

Transcription

1 OWEA Annual Conference Mason, OH June 19, 2013, Operations, 11:00-11:45AM Wet Weather and Advanced Treatment: Procurement Strategies to Secure the Right Technology Bill Meinert, PE, O Brien & Gere

2 Often The Situation Maintain aging WW systems Comply with effluent limits Monthly average, weekly limit, instantaneous maximum Achieve higher levels of treatment Tighter limits, plus Annual or Seasonal nutrient removal allocations? Consider innovative technologies (to name a few acronyms) High Rate Flocculation Settling (HRFS) Moving-Bed Biofilm Reactors (MBBR) Integrated Fixed-Film Activated Sludge (IFAS) Membrane Bioreactor (MBR) Limited Qualified Providers Technology, Equipment 2

3 What Do You Do? You Must Ensure Compliance Meet Project Goals & Objectives Limit Capital Expenditures Complete the Project on Time Control O&M Costs Alternative Contracting Methods can be part of the Solution Cost, and Or Equal Funding Agency requirements (two, or none at all?) Significantly different? Re-design Potential sole-sourcing, costs, and vendor packaging Schedule, accelerate to meet a deadline? Final Design, Construction Phasing 3

4 Contracting Methods Traditional Design / Bid / Construct Base Bid / Alternate Negotiate & Assign Pre-Purchase Contract Design-Build Performance Guarantee Main process, supporting systems Overall Plant Performance Average, Peak Examples Pros & Cons Influencing Events How the contracting method faired 4

5 Example Project MBR (Woodstock, VA) System growth Sludge disposal challenges Consent order Inflow Interim operation plan Chesapeake Bay Program Permit renewal Compliance, nutrient removal 3-4 mg/l TN, 0.3 mg/l TP Project financing Grant, Loan Small secondary clarifiers Limited aerobic digestion facilities Actual floodplain 5

6 MBR System Optimize footprint for the site 6

7 Mobile MBR System Construction sequencing (0.5-MGD unit) Early training opportunity (0.5, 2-MGD) Pre-purchase element (24-mo. rental) Before this mobile 7

8 2-MGD Expansion & ENR Upgrade Basis of Design Methanol Ferric Influent BOD Anaerobic Anoxic Swing Aerobic1 Aerobic2 Post Anoxic ZW Tank Effluent DeOx WAS 8

9 2-MGD Expansion & ENR Upgrade Design 9

10 2-MGD Expansion & ENR Upgrade Design 10

11 2-MGD Expansion & ENR Upgrade Design 11

12 Woodstock Experience Pros & Cons Had to do it site, schedule, no full-scale competition Base Bid awarded, cost escalation? One experienced vendor instead, do Negotiate & Assign? Combined MBR and WAS Storage / Thickening technologies Very forgiving, excellent effluent performance Influencing Events 500-Year Flood, two weeks after startup General contractor with limited experience, Direct line of communication Growth evaporated with the economy (2008) Second bioreactor for EQ, O&M cost control How the contracting method faired ENR Basis Of Design confirmation, O&M Effective design, construction, operation Training, training, training 12

13 Example Project SBR (Lock Haven, PA) New Plant Old Plant Existing Plant Some components >50-70 years old New Owner preferences Weather protection, No moving parts in basins 13

14 Advanced BNR Upgrade 3.75 MGD Plant NPDES effluent limits 25 mg/l CBOD 30 mg/l TSS 6 mg/l TN 0.8 mg/l TP Nitrogen Removal Sequencing batch Reactors (SBR) Phosphorus removal Chemical SBR (clarification) Tertiary filtration 14

15 SBR Operation Nutrient Removal Anoxic fill Denitrification Oxic react BOD removal Nitrification Coagulant addition Settle Clarification Decant Effluent discharge Idle WAS discharge 15

16 SBR Components Multiple SBR tanks in different cycles Jet Mixing & Aeration Headers Effluent Decanter (floating, with submerged nozzles) Anoxic Fill 16

17 Phosphorus Removal Processes Tertiary Filtration Four parallel tanks Cloth-type disc filters 10 discs per tank Sized for SBR decant rate (10.9 MGD) 5 min flocculation tank Coagulant addition with flash mixing Sized for future expansion Sized for future lower TP limits (< 0.3 mg/l) 17

18 Lock Haven Experience Pros & Cons Had to do it? Base Bid awarded Biological treatment and Aerobic digestion Influencing Events Project award delays due to funding Further delays due to onsite MSW Proprietary microwave UV and system re-design, change order Could contracting method have mitigated? How the contracting method faired Effective No redesign, Coordinated I&C Interlocking SBR & Cloth-Media Filter guarantees Contract 1 documents and shop drawings for Contract 2 bidders Precast offering ($), but Piping supports and equipment clearances On our fourth Manufacturer s Project Manager! 18

19 Example Project IFAS (Massillon, OH) TP removal evaluation part of facilities plan update 19

20 City of Massillon, OH Roughing Filter-Ox. Ditch, Bio-P & Growth Removing the Roughing Filters for odors transferred BOD Load to Ditches, 1.2-MGD capacity increase and Bio-P zones were too much for the Ditches & Clarifiers. 20

21 City of Massillon, OH Roughing Filter-Ox. Ditch, Bio-P & Growth IFAS was good enough for BOD & Nitrification, but limited for Bio-P and Denitrification if unit redundancy was needed. 21

22 City of Massillon, OH Roughing Filter-Ox. Ditch, Bio-P & Growth 22

23 Massillon Experience Pros & Cons It ain t done yet! BioWin & GPS-X Modeling and vendor sizing are beginning to correlate, finally! Influencing Events Project design award delays same deadline Pre-purchasing will be necessary for acceleration How the contracting method faired We shall see Just 2 vendors may number 7 or 8 now 23

24 Example Project MBBR (Martinsburg, WV) Qualifications, Life Cycle Current (MBBR) & Future IFAS?) Bases of Design, plus CSO Treatment Ranking & Scoring System Impacts on other Elements Integrating in final design 24

25 Piloting Moving-Bed Biofilm Reactor, w/ and w/o Nitrification Piloted September 2011 March 2012 Warm and cold Dry and wet Internal Recycle Adjustments Air distribution & DO control But Secondary Underflow BOD-limited (add Carbon) Period #1 - Nitrification MBBR startup, warm & cold MBBR vs. Tower Periods #2, 3 - DO in Tower Effluent cold, baseline & adjusted carbon Pre- & Post-anoxic MBBR sizing 25

26 Piloting Supplemental Carbon Carbon Source(s) Acetic Acid used for Pilot, and Basis of Design Alternatives Design Feed Rates Confirmed Nitrification MBBR vs. Tower Effluent Carbon Feed Approximately 3x with Tower But, Primary Effluent BOD:NO 3 -N 40% higher in Period #1, compared to #2 & #3 Deoxygenation Potential - SOUR Tests Little to no bio-activity to reduce DO 26

27 Piloting Influent & Primary Effluent Coagulant Jar Testing Coagulant Testing Ferric better than Alum Non-reactive P mg/l TP? 27

28 Piloting Analysis & Basis Of Design Process Parameters Evaluated TN Removal when BOD-Limited, Higher with Carbon to compensate Minimum Wastewater Temperature Effects Nitrification Check, Effect of DO on MBBR Process Internal Recycle Rate (adjusted for Pilot influent conditions) Coagulant Feed requirements for TP polishing MBBR Surface Area Loading Rates (SALR) and SA Removal Rates (SARR) BOD, COD, NO x -N, NH 3 -N, TKN Significant differences between the three leading MBBR vendor offerings Pre-Purchase Contract Documents, Evaluated Bid Process 28

29 MBBR is Right for Martinsburg, but More Chem-P Than Bio-P 29

30 Piloting & Pre-Purchasing MBBR Layout Pre-Purchase Contract Documents Bid Form Total Capital Furnish & Deliver Breakdown Media, Mixers, Aeration Diffuser System, Services Proposed Design Volumes, Aeration, Mixing, %-Fill, Carbon Evaluation of Bids 60% Total Life Cycle Cost 40% MBBR Supplier Qualifications & Experience Technical Requirements & Constraints Footprint, Tanks #1 & #2 Reserve %-Fill Contingency Design Requirements for ENR Performance Guarantee 30

31 Nutrient Removal Flow Schematics with Biofilm Carriers Fixed -film (MBBR), Integrated Fixed-film Activated Sludge (IFAS) Function of Process Configuration 31

32 WWTP Upgrade Design (2012) CSO Treatment 32

33 WWTP Upgrade Design (2012) TP Removal by day, CSO Treatment by night 33

34 WWTP Upgrade Design (2012) Procurement, Alternatives?, Distributed Design Elements, Option Bid Scope of Supply Guarantees 34

35 Martinsburg Experience Pros & Cons Extensive knowledge gained through Piloting & Pre-Purchase Performance guarantee fine-tuned Construction sequencing and deadline not achievable without it Option-Bidding the HRFS will it work out, and within budget? Modeling and vendor sizing not so good for MBBR Significant vendor differences Influencing Events Project budget Uncertain funding agency requirements How the contracting method faired Effective No redesign, Coordinated I&C Interlocking MBBR & HRFS guarantees and operating modes Contract 1 documents and shop drawings for Contract 2 bidders 35

36 Overall Experience, Opinions, Conjecture, Random Thoughts You have Options Traditional design and bid as one contract List many or none, Establish the basis of design standard Pre-Purchase, Negotiate & Assign, Design-Build Nothing s Perfect, Case-by-case Decision-making Get What You Need, and Follow Public Procurement Requirements Opportunity to Fit Technology with Overall Project (hand in glove) Method to Meet Accelerated Schedules Reduce Chances of Re-design (cost, time) 36

37 OWEA Annual Conference Mason, OH June 19, 2013, Operations, 11:00-11:45AM Bill Meinert, 4201 Mitchellville Road, Suite 500, Bowie, MD 20716, (301)

38 38 #obgpresentation