constraints and threats - are they leading us to opportunities? bacwa biosolids workshop june 2,...
TRANSCRIPT
Constraints and Threats - are They Leading Us to
Opportunities?
Constraints and Threats - are They Leading Us to
Opportunities?
BACWA Biosolids Workshop
June 2, 2008
Perry Schafer, PE, BCEE, Brown and Caldwell
BACWA Biosolids Workshop
June 2, 2008
Perry Schafer, PE, BCEE, Brown and Caldwell
Bay Area Clean Water Agencies
Constraints/threats are having an impactConstraints/threats are having an impact
Adverse public perception (land application, etc.)
Energy price increases
Landfilling limits
Regulatory controls
Biosolids cost escalation and uncertainty
Adverse public perception (land application, etc.)
Energy price increases
Landfilling limits
Regulatory controls
Biosolids cost escalation and uncertainty
Price for Class B/A cake trucking and use/disposalPrice for Class B/A cake trucking and use/disposal
100
80
60
40
20
0
100
80
60
40
20
0
$ / W
et T
on
California Price Range
Year2010200520001995199019851980
Calif. Agencies have/are responding to change Calif. Agencies have/are responding to change
Preference for non-land-application disposition
Improved dewatering and drying systems
More efficient digestion, and boosting biogas production
RFPs and contracts for privatized/merchant facilities
Research and demonstration projects (muni and private)
Preference for non-land-application disposition
Improved dewatering and drying systems
More efficient digestion, and boosting biogas production
RFPs and contracts for privatized/merchant facilities
Research and demonstration projects (muni and private)
Rough cost comparison(2008 time frame)Rough cost comparison(2008 time frame)
Class B Truck/ Land Ap
OpenCompost
Closed Compost
Heat Dry
Alkaline Treat.
AirDry
Lagoon/ Air Dry
Class A Digest.
$/w
et to
n (d
iges
ted-
dew
ater
ed)
150
100
0
50
Costs for digestion and dewatering not included.
Class A
w/o Dewatering
Note: Assumes ~25% cake solids as basis.
Sewage sludge disposal in the EC and GermanySewage sludge disposal in the EC and Germany
(from Robert Schmidt, City of Munich, Germany, 2008)
Where is EC/Germany headed?Where is EC/Germany headed?
Traditional land application greatly constrained Landfill almost eliminated Incineration and energy recovery
continue/expand Co-firing with coal or biowaste in power plants Use in cement kilns Drying (solar, waste heat) Greater digestion efficiency GHG and renewable energy – prime issues
Traditional land application greatly constrained Landfill almost eliminated Incineration and energy recovery
continue/expand Co-firing with coal or biowaste in power plants Use in cement kilns Drying (solar, waste heat) Greater digestion efficiency GHG and renewable energy – prime issues
Summary – Key Take-awaysSummary – Key Take-aways
Maximize digestion efficiency
Assess low-energy methods for volume reduction
Consider biosolids products for energy use
GHG and energy issues becoming much more important
Maximize digestion efficiency
Assess low-energy methods for volume reduction
Consider biosolids products for energy use
GHG and energy issues becoming much more important