Wet Weather and Advanced Treatment: Procurement · PDF fileStrategies to Secure the Right Technology OWEA Annual Conference ... plus Annual or Seasonal nutrient removal allocations?

© 2013 O’Brien & Gere

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

OWEA Annual Conference – Mason, OH – June 19, 2013, Operations, 11:00-11:45AM

Bill Meinert, PE, O’Brien & Gere


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

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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

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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

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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

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MBR System

Optimize footprint for the site

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Mobile MBR System

Construction sequencing (0.5-MGD unit)

Early training opportunity (0.5, 2-MGD)

Pre-purchase element (24-mo. rental)

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Before this … mobile


2-MGD Expansion & ENR Upgrade | Basis of Design

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Anaerobic Anoxic Swing Aerobic1 Aerobic2 ZW Tank

WAS

Effluent

Methanol

Post AnoxicInfluent BOD

Ferric

DeOx


2-MGD Expansion & ENR Upgrade | Design

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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


ENR Basis Of Design confirmation, O&M

Effective – design, construction, operation

› Training, training, training

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Example Project – SBR (Lock Haven, PA)

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Existing Plant

Some components >50-70 years old

New – Owner preferences – Weather protection, No moving parts in basins

New Plant

Old Plant


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

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SBR Operation | Nutrient Removal

Anoxic fill

Denitrification

Oxic react

BOD removal

Nitrification

Coagulant addition

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Settle

Clarification

Decant

Effluent discharge

Idle

WAS discharge


SBR Components

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Anoxic Fill

Multiple SBR tanks in different cycles

Effluent Decanter (floating, with submerged nozzles)

Jet Mixing & Aeration Headers


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)

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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?


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!

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Example Project – IFAS (Massillon, OH)

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TP removal evaluation part of facilities plan update


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

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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.



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IFAS was good enough for BOD & Nitrification, but limited for Bio-P and Denitrification if unit redundancy was needed.



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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


We shall see … “Just 2” vendors may number 7 or 8 now

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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

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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

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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:NO3-N 40% higher in Period #1, compared to #2 & #3

Deoxygenation Potential - SOUR Tests

› Little to no bio-activity to reduce DO

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Piloting | Influent & Primary Effluent Coagulant Jar Testing

Coagulant Testing – Ferric better than Alum

› Non-reactive P - 0.2 mg/L TP?

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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, NOx-N, NH3-N, TKN

Significant differences between the three leading MBBR vendor offerings

Pre-Purchase Contract Documents, Evaluated Bid Process

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

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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

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Nutrient Removal Flow Schematics with Biofilm Carriers

Fixed -film (MBBR), Integrated Fixed-film – Activated Sludge (IFAS)

Function of Process Configuration

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WWTP Upgrade Design (2012)

CSO Treatment

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TP Removal “by day”, CSO Treatment “by night”

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Procurement, Alternatives?, Distributed Design Elements, Option Bid

Scope of Supply

Guarantees

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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


Effective – No redesign, Coordinated I&C

Interlocking MBBR & HRFS guarantees – and operating modes

Contract 1 documents and shop drawings for Contract 2 bidders

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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)

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© 2013 O’Brien & Gere 37

OWEA Annual Conference – Mason, OH – June 19, 2013, Operations, 11:00-11:45AM

Bill Meinert, 4201 Mitchellville Road, Suite 500, Bowie, MD 20716, [email protected], (301) 731-1130

mailto:[email protected]

© 2013 O’Brien & Gere 38 #obgPresentation