Biosolids Management Program Update Briefing for Blue Plains Regional Committee August 23, 2007...
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Transcript of Biosolids Management Program Update Briefing for Blue Plains Regional Committee August 23, 2007...
Biosolids ManagementProgram Update
Briefing for Blue Plains Regional Committee
August 23, 2007
2
AgendaAgenda
• Review of Approved 1999 Biosolids Management Plan
• Approach to BMP Implementation
• BMP Schedule Update
• Technical Workshop Summary• Alternatives Screened
• Alternatives Selected for Further Evaluation
• Preliminary Findings
• Next Steps
• Review of Approved 1999 Biosolids Management Plan
• Approach to BMP Implementation
• BMP Schedule Update
• Technical Workshop Summary• Alternatives Screened
• Alternatives Selected for Further Evaluation
• Preliminary Findings
• Next Steps
3
Review of Approved 1999 Biosolids Management Plan Review of Approved 1999 Biosolids Management Plan
4
Montgomery
Loudoun
FairfaxFairfax
Prince George’s
ArlingtonArlington
D.C.
Decision Science was usedto build consensus for Biosolids Master Plan
Decision Science was usedto build consensus for Biosolids Master Plan
Is logical and defensibleIs logical and defensible
Accommodates multiple stakeholders
Considers risks and uncertainties along with cost
Efficiently analyzes information
Fairfax
5
through Bid process5Manage Risk & Evaluate Alternatives
4Collect & Verify Information
3Determine Values & Alternatives
2Frame the Problem
The Decision Science Process
1Leadership & Commitment
Develop Develop Master Plan/ Master Plan/
BriefingBriefing
WORKSHOP 1WORKSHOP 1WORKSHOP 2WORKSHOP 2
WORKSHOP 3WORKSHOP 3WORKSHOP 4WORKSHOP 4
WASA Staff, Blue Plains Regional/Tech. Committees
Board of DirectorsBoard of Directors
Operations CommitteeGM/Chief Engineer
MAR APR JUN JUL
DEC
ISIO
N
DEC
ISIO
N
PRO
CES
S ST
EPS
PRO
CES
S ST
EPS
6
U.S. EPA, VDH, MDE, DC DOH
MAY
WASA Staff
6
Decision Science Participants in 1999
Decision Science Participants in 1999
• Operations Committee (6)
• Blue Plains Regional and Technical Committees (8)
• WASA Management and Technical Staff (9)
• Regulatory (EPA, DC, VA, MD) and Regional Officials (8)
• Program Management Group
• Operations Committee (6)
• Blue Plains Regional and Technical Committees (8)
• WASA Management and Technical Staff (9)
• Regulatory (EPA, DC, VA, MD) and Regional Officials (8)
• Program Management Group
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Consensus on Key Guiding Principles in development of 1999 BMP
Consensus on Key Guiding Principles in development of 1999 BMP
• The status quo is unacceptable
• WASA must go beyond regulatory compliance to world class operations consistent with the National Biosolids Partnership to ensure long-term program viability
• WASA cannot contract away its responsibility
• Diversity is required through multiple modes of end use and disposal to prepare for changing markets, politics and regulations.
• On-site processing maximizes WASA’s control
• Public and political support is needed for BMP success
8
Top Alternatives centered around Digestion because of risk
avoidance and benefits
Top Alternatives centered around Digestion because of risk
avoidance and benefits
All alternatives considered that land application would
continue as long as it remained viable but recognized
considerable chance it would eventually not be viable
• Full Digestion going to 100% heat drying in the future
• Full Digestion with 1/3 to land application, 1/3 to drying, and 1/3 to co-incineration
• Full digestion with ½ to land application and ½ to heat drying
9
BOD Approved Action Plan – Sept 1999
BOD Approved Action Plan – Sept 1999
• Prepare Facility Plan based on full digestion and future drying
• Continue land application as long as financially advantageous to WASA
• Prepare Project Delivery Plan
• Continue to evaluate alternative technologies
• Revise Facility Plan if other options deemed implementable
• Implement baseline improvements to preserve land application and improve O&M
• Is this plan still applicable?
10
What has changed since 1999?What has changed since 1999?
• WASA has new, very costly programs• Long Term Control Plan (mandated)• Chesapeake Bay Program – ENR (mandated)
• BMP baseline improvements have been implemented:• Additional dewatering (centrifuges) with improved lime mixing• Upgrade of gravity thickener facility• Design of biological sludge thickening facility (90% complete)
• BMP Baseline improvements have resulted in:• Improved lime stabilized product – reduced odors and lime
dosage• EMS certification under the National Biosolids Partnership• EPA first place 2005 award for best biosolids program in the
U.S.• Continued viability of land application at reasonable cost
• WASA has new, very costly programs• Long Term Control Plan (mandated)• Chesapeake Bay Program – ENR (mandated)
• BMP baseline improvements have been implemented:• Additional dewatering (centrifuges) with improved lime mixing• Upgrade of gravity thickener facility• Design of biological sludge thickening facility (90% complete)
• BMP Baseline improvements have resulted in:• Improved lime stabilized product – reduced odors and lime
dosage• EMS certification under the National Biosolids Partnership• EPA first place 2005 award for best biosolids program in the
U.S.• Continued viability of land application at reasonable cost
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What has changed since 1999?What has changed since 1999?
• Enforcement, starting in 2008, of a more stringent nutrient management program in Virginia to control nitrogen and phosphorus will impact biosolids land application rates
• WASA has contracted up to 200 wt/d of biosolids for processing at offsite composting facility in Virginia for next 5 years
• Class A digestion processes have evolved from prototypes to proven technology at large scale (Issues with React./Regrowth remain)
• Some biosolids technologies (e.g. SlurryCarb) have advanced from “embryonic” to “innovative” as defined by U.S. EPA. Cost at large scale facility not proven, but bears watching.
• Project capital cost escalation for planning and budgeting is no longer as predictable as it was.• Escalation at 3% per annum used to be reliable• Project bids in the past 2 years have been significantly over budget, due in
large part to escalation in construction materials• Projecting rate of cost escalation going forward is not certain
• Enforcement, starting in 2008, of a more stringent nutrient management program in Virginia to control nitrogen and phosphorus will impact biosolids land application rates
• WASA has contracted up to 200 wt/d of biosolids for processing at offsite composting facility in Virginia for next 5 years
• Class A digestion processes have evolved from prototypes to proven technology at large scale (Issues with React./Regrowth remain)
• Some biosolids technologies (e.g. SlurryCarb) have advanced from “embryonic” to “innovative” as defined by U.S. EPA. Cost at large scale facility not proven, but bears watching.
• Project capital cost escalation for planning and budgeting is no longer as predictable as it was.• Escalation at 3% per annum used to be reliable• Project bids in the past 2 years have been significantly over budget, due in
large part to escalation in construction materials• Projecting rate of cost escalation going forward is not certain
12
Approach to BMP Implementation Update
Approach to BMP Implementation Update
• Updating 1999 BMP to reflect advances in biosolids technologies and changes in regulations and market conditions. Process involves two screening steps:• Preliminary screening of process alternatives from thickening to
product end use• In-depth evaluation of screened alternatives
• Monitoring construction market. Presented initial report to EQOC in April 2007
• Conducted 1st screening workshop on June 20-21, 2007 involving expert peer reviews. Screened 16 alternatives; selected 4 for further evaluation
• Developing plans for short-term projects to extend the useful life of existing biosolids facilities until BMP is implemented. Identified CIP budget needs
• Updating 1999 BMP to reflect advances in biosolids technologies and changes in regulations and market conditions. Process involves two screening steps:• Preliminary screening of process alternatives from thickening to
product end use• In-depth evaluation of screened alternatives
• Monitoring construction market. Presented initial report to EQOC in April 2007
• Conducted 1st screening workshop on June 20-21, 2007 involving expert peer reviews. Screened 16 alternatives; selected 4 for further evaluation
• Developing plans for short-term projects to extend the useful life of existing biosolids facilities until BMP is implemented. Identified CIP budget needs
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•Phase I: Develop and screen preliminary process alternative -
CompleteMeet with BPRC -
08/23/07
•Phase II: Develop alternatives related toprocess, constructability and project delivery - 09/15/07
Present status update to EQOC- 09/20/07Meet with BPRC - 10/25/07
•Phase III: Develop draft BMP - 11/01/07
Present draft to EQOC - 11/15/07
Meet with BPRC - 12/28/07
•Phase IV: Prepare Final BMP - 12/31/07
•Phase I: Develop and screen preliminary process alternative -
CompleteMeet with BPRC -
08/23/07
•Phase II: Develop alternatives related toprocess, constructability and project delivery - 09/15/07
Present status update to EQOC- 09/20/07Meet with BPRC - 10/25/07
•Phase III: Develop draft BMP - 11/01/07
Present draft to EQOC - 11/15/07
Meet with BPRC - 12/28/07
•Phase IV: Prepare Final BMP - 12/31/07
Updated BMP Implementation ScheduleUpdated BMP Implementation Schedule
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Summary of Technical WorkshopSummary of Technical Workshop
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Biosolids Team ConsultantsBiosolids Team Consultants
• Terry Logan –Consultant – Land application and lime stabilization
• Tim Shea – CH2M – Digestion• Perry Schafer – B&C – Digestion• Alan Cooper – Parsons – Heat drying• Frank Rogalla – B&V – Cambi
• Terry Logan –Consultant – Land application and lime stabilization
• Tim Shea – CH2M – Digestion• Perry Schafer – B&C – Digestion• Alan Cooper – Parsons – Heat drying• Frank Rogalla – B&V – Cambi
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Alternatives ConsideredAlternatives Considered
Drying
Class A Processing
Dewatering Centrifuge, BFP
Thickened Liquid Sludge
Class A
LandApplication
Incineration
Pelletization
Alkaline StabilizationClass A or B
Class B
LandFill
Digestion(MAD, TPAD, AGPD)
CambiEH
Pasteurizations
Ash into bricks
Gasification
Ash
EnerTech, E-fuel
Fertilizer
Ash
Composting
Minergy, Aggregates
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Process Train
A.1
A.2
A.3
A.4
A.5
A.6
A.7
B.1
B.2
B.3
B.4
B.5
B.6
B.7
B.8
TABLE 4 - SOLIDS PROCESSING ALTERNATIVES RANKING
ID
Thickened Sludge
Centrifuge Dew atering Incineration
Centrifuge Dew atering
Thickened Sludge
Drying
Ash to bricks
Enzymatic Hydrolysis
Mesophilic Anaer Dig
To Land Application
Centrifuge Dew atering
Lime Stabilization
To Land Application
Thickened Sludge
Thickened Sludge
Centrifuge Dew atering
Thickened Sludge
Acid-Gas CentrifugeDew atering
To Land Application
Thickened Sludge
Centrifuge Dew atering
Drying Vitrif icationGlass
Aggregate
Auto Thermal Aerobic Dig
Temp Phased Anaer Dig
To Land Application
Thickened Sludge
Centrifuge Dew atering
To Land Application
Centrifuge Dew atering
Composting To Land Application
Thickened Sludge
Thickened Sludge
Centrifuge Dew atering
To Landfill
Thickened Sludge SlurryCarb
Centrifuge Dew atering
Fuel
Temp Phased Anaer Dig (Eggs)
To Land Application
Thickened Sludge
Centrifuge Dew atering
Temp Phased Anaer Dig (Pancakes)
To Land Application
Thickened Sludge
Centrifuge Dew atering
Thickened Sludge
Mesophilic Anaer Dig (Primary)
Centrifuge Dew atering
Drying To Land Application
Thermophilic Anaer Dig
To Land Application
Thickened Sludge
Centrifuge Dew atering
Mesophilic Anaer Dig
To Land Application
Thickened Sludge
Centrifuge Dew atering
Anaerobic Digestion
Alternative Process Trains Screened at
Workshop
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Screening CriteriaScreening Criteria
• Capital and O&M Cost• Present Worth – Equivalent Annual Cost
• Non-Economic Criteria• Process
Proven technology Reliability – consistency of product Ease of Operations Ease of Maintenance
• Implementation Ease of Construction/Duration Project Delivery Options – need for DBO Air Quality Impacts Ease of Implementation (site constraints) Assurability of Permitting (NCPC, CFA, CAA, FAA, DCRA) Compatibility with Existing Facilities Public Perception/Acceptance Overall Implementability
• End Product Marketability/Acceptability Sustainability/Regulatory Changes/Risk Diversity (Class A)
• Capital and O&M Cost• Present Worth – Equivalent Annual Cost
• Non-Economic Criteria• Process
Proven technology Reliability – consistency of product Ease of Operations Ease of Maintenance
• Implementation Ease of Construction/Duration Project Delivery Options – need for DBO Air Quality Impacts Ease of Implementation (site constraints) Assurability of Permitting (NCPC, CFA, CAA, FAA, DCRA) Compatibility with Existing Facilities Public Perception/Acceptance Overall Implementability
• End Product Marketability/Acceptability Sustainability/Regulatory Changes/Risk Diversity (Class A)
19
Alternatives that Remain for Further Evaluation
Alternatives that Remain for Further Evaluation
Mainstream Alternatives (Digestion–based) :1. Thickening Acid Gas/TPAD Centrifuge Land App2. Thickening Acid Gas/Meso dig. Centrifuge Drying Land App3. Thickening Centrifuge Cambi Meso dig. BFP Land App4. Thickening ATAD TPAD Centrifuge Land App
Notes: All alternatives are sized for maximum month (433 dt/d) loading. TN treatment will be assessed for each. Options 1&4 may require BFP for dewatering.
These alternatives met preliminary screening criteria (proven technology, cost, product, implementability)
Peak Shaving Options:1. Thickening Centrifuge Lime Stab (upgraded) Land App2. Thickening Centrifuge Composting Land App3. Thickening Centrifuge Landfill
Note: These are options that are currently usable
Mainstream Alternatives (Digestion–based) :1. Thickening Acid Gas/TPAD Centrifuge Land App2. Thickening Acid Gas/Meso dig. Centrifuge Drying Land App3. Thickening Centrifuge Cambi Meso dig. BFP Land App4. Thickening ATAD TPAD Centrifuge Land App
Notes: All alternatives are sized for maximum month (433 dt/d) loading. TN treatment will be assessed for each. Options 1&4 may require BFP for dewatering.
These alternatives met preliminary screening criteria (proven technology, cost, product, implementability)
Peak Shaving Options:1. Thickening Centrifuge Lime Stab (upgraded) Land App2. Thickening Centrifuge Composting Land App3. Thickening Centrifuge Landfill
Note: These are options that are currently usable
20
Preliminary Findings -Alternatives
Preliminary Findings -Alternatives
• Loading rates:• 330 dt/d – Average day
• 433 dt/d – Maximum month Use for digester sizing
• 530 dt/d – Maximum week
• 630 dt/d – Maximum 3-day
• Use lime stab/composting/landfill for peak shaving loads > 433 dt/d
• Digestion is a component of each alternative• Remains the foundation for the BMP
• Digestion sized to minimize capital cost
• Digestion is a pre-requisite to heat drying• To control odors and increase product market options
• To reduce capital cost of drying facility
• To provide fuel for drying
• Heat drying is a component of 1 alternative• Can be add-on to other alternatives
• One of few technologies that can assure multiple outlets for product and thus can be sustainable for 25 years
• Constructability and implementability must be addressed now
• Loading rates:• 330 dt/d – Average day
• 433 dt/d – Maximum month Use for digester sizing
• 530 dt/d – Maximum week
• 630 dt/d – Maximum 3-day
• Use lime stab/composting/landfill for peak shaving loads > 433 dt/d
• Digestion is a component of each alternative• Remains the foundation for the BMP
• Digestion sized to minimize capital cost
• Digestion is a pre-requisite to heat drying• To control odors and increase product market options
• To reduce capital cost of drying facility
• To provide fuel for drying
• Heat drying is a component of 1 alternative• Can be add-on to other alternatives
• One of few technologies that can assure multiple outlets for product and thus can be sustainable for 25 years
• Constructability and implementability must be addressed now
21
Preliminary Findings -How to reduce digester costs
Preliminary Findings -How to reduce digester costs
• Size digester facility for max. month design loading (433 dt/d); use peak shaving
• Do NOT provide standby unit
• Simplify digester construction through use of silo/cylindrical shaped vessels, pre-cast side panels, and waffle bottoms
• Can approximate egg digester performance and advantages
• Simplifies foundation design lower capital cost
• Reduces construction complexity lower capital cost
• Increases contractor competition lower capital cost
• Reduces construction schedule length lower capital cost
• Silo shaped digesters approx. dimensions• Wall height - 60 ft.
• Diameter - 100-125 ft.
• Silo shaped digesters have been built• Vancouver, BC (3.2 MG each)
• Sacramento, CA (3.7 MG each)
• Western Lake Superior Sanitation District
• Wichita, KS
• Re-thicken sludge to >5% to reduce digester volume. Each ½% saves about 2-3 MG volume. Pilot testing needed to confirm feasibility
• Size digester facility for max. month design loading (433 dt/d); use peak shaving
• Do NOT provide standby unit
• Simplify digester construction through use of silo/cylindrical shaped vessels, pre-cast side panels, and waffle bottoms
• Can approximate egg digester performance and advantages
• Simplifies foundation design lower capital cost
• Reduces construction complexity lower capital cost
• Increases contractor competition lower capital cost
• Reduces construction schedule length lower capital cost
• Silo shaped digesters approx. dimensions• Wall height - 60 ft.
• Diameter - 100-125 ft.
• Silo shaped digesters have been built• Vancouver, BC (3.2 MG each)
• Sacramento, CA (3.7 MG each)
• Western Lake Superior Sanitation District
• Wichita, KS
• Re-thicken sludge to >5% to reduce digester volume. Each ½% saves about 2-3 MG volume. Pilot testing needed to confirm feasibility
New 3.7 MG Digester – Mid 1990s Sacramento, CA
Pre-cast panels and pre-cast roof beams/panels significantly reduce cost and construction schedule
23
Preliminary Findings – Biosolids Markets
Preliminary Findings – Biosolids Markets
• WASA’s biosolids land application program is viable and cost effective – But long-term viability may be impacted by: • Public sentiment – political reaction• Regulations, including nutrient management (P limits)• Competition from animal waste
• WASA may be well served with a Class A product as a hedge against future land application changes• Provides a better quality product• Provides greater opportunities for distribution and marketing
• Heat dried product offers multiple markets• Fuel• Land application• Horticulture• Fertilizer
• Markets and reuse/disposal outlets for biosolids products should drive the final alternatives evaluation and selection process
• WASA’s biosolids land application program is viable and cost effective – But long-term viability may be impacted by: • Public sentiment – political reaction• Regulations, including nutrient management (P limits)• Competition from animal waste
• WASA may be well served with a Class A product as a hedge against future land application changes• Provides a better quality product• Provides greater opportunities for distribution and marketing
• Heat dried product offers multiple markets• Fuel• Land application• Horticulture• Fertilizer
• Markets and reuse/disposal outlets for biosolids products should drive the final alternatives evaluation and selection process
24
Issues Impacting Financial ViabilityIssues Impacting Financial Viability
• Available CIP budget for biosolids• Portion expected to be used for near term SPB improvements• May be adequate for new digester concept
• Construction cost indices continue to increase from 3% to 8% per year
• Public works construction market projected to remain robust, partly driven by Chesapeake Bay Program
• Transfer of management of Virginia biosolids land application to DEQ will increase cost
• Predictability of rate of cost escalation
• Available CIP budget for biosolids• Portion expected to be used for near term SPB improvements• May be adequate for new digester concept
• Construction cost indices continue to increase from 3% to 8% per year
• Public works construction market projected to remain robust, partly driven by Chesapeake Bay Program
• Transfer of management of Virginia biosolids land application to DEQ will increase cost
• Predictability of rate of cost escalation
25
BOD Approved Action Plan Sept 1999 - still applicable?
BOD Approved Action Plan Sept 1999 - still applicable?
• Prepare Facility Plan based on full digestion and future drying - Implement digestion of base load and future drying if regional land application dictates
• Continue land application as long as financially advantageous to WASA - Yes
• Prepare Project Delivery Plan – Update for new digester approach
• Continue to evaluate alternative technologies - Yes• Revise Facility Plan if other process or beneficial reuse
options deemed implementable - yes• Implement baseline improvements to preserve land
application and improve O&M – Mostly done - additional improvements now needed
• Analysis indicates no reason to change BOD Approved BMP• No need to repeat Decision Science process• New updated implementation plan
• Prepare Facility Plan based on full digestion and future drying - Implement digestion of base load and future drying if regional land application dictates
• Continue land application as long as financially advantageous to WASA - Yes
• Prepare Project Delivery Plan – Update for new digester approach
• Continue to evaluate alternative technologies - Yes• Revise Facility Plan if other process or beneficial reuse
options deemed implementable - yes• Implement baseline improvements to preserve land
application and improve O&M – Mostly done - additional improvements now needed
• Analysis indicates no reason to change BOD Approved BMP• No need to repeat Decision Science process• New updated implementation plan
26
Possible Implementation Schedule
Possible Implementation Schedule
Activity Duration Complete
Preliminary design 8 mo. Feb 28, 2008
Design procurement 6 mo. Mar 31, 2008
Design 12 mo. Mar 31, 2009
Bidding 6 mo. Sep 30, 2010
Construction 3 years Sep 30, 2012
Startup 6 mo. Dec 31, 2012
Note: Some activities run concurrentlyNote: Some activities run concurrently
27
Next StepsNext Steps
• Develop details for alternatives• Digester process and TN treatment options• Mass and energy balances• Digester shapes that approximate eggs• Digestion facility layout and sizing• Capital costs and life cycle costs• Constructability and project delivery• Regulatory issues• Market details
• Make periodic updates to EQOC (Sep/Nov) and BOD (Oct/Jan)
• Make presentations to Blue Plains Regional Committee (Aug/Oct/Dec)
• Develop details for alternatives• Digester process and TN treatment options• Mass and energy balances• Digester shapes that approximate eggs• Digestion facility layout and sizing• Capital costs and life cycle costs• Constructability and project delivery• Regulatory issues• Market details
• Make periodic updates to EQOC (Sep/Nov) and BOD (Oct/Jan)
• Make presentations to Blue Plains Regional Committee (Aug/Oct/Dec)