Producing Class A Biosolids The Chicago Way
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Transcript Producing Class A Biosolids The Chicago Way
P r o te c tin g O u r W a te r E n v ir o n m e n t
Metropolitan
Water
Reclamation
M
etropolitan W
ater R
eclam ation District
D istrict of
of Greater
G reater Chicago
C h icago
Producing Class A Biosolids The
Chicago Way – A Unique PFRP
Equivalency Process
Dr. Lakhwinder S. Hundal
Sr. Environmental Soil Scientist
EM&R Department
Metropolitan Water Reclamation District of Greater Chicago
NWBMA Conference, Chelan, WA Sept 19 – 21, 2010
About The MWRD
Founded in 1889 to protect water quality of Lake Michigan
Services Cook County Illinois including city of Chicago and
125 suburban communities
Service area covers 875 sq. miles and includes 5.5 million
people + industry equivalent to 5.7 million people
Operates seven water reclamation plants handling daily
flow of 1.5 billion gallons
– Fill 450 acre swimming pool 10 ft. deep daily
Produces ~180,000 dry tons biosolids annually
– Takes ~ 15,000 semi trailers to haul annual production
It is a Big Pile of Poop!!
Evolution of Solids Management …
Solids management was not
an issue in 1889
Became a necessity in 1920s
Constructed Imhoff Tanks
• Calumet WRP in 1922
• Stickney WRP in 1930
Imhoff tanks provided sludge
storage and digestion
Evolution of Solids Management …
contd.
Installed lagoons in 1937 to handle IHS, WAS, & PS
Long-term storage discontinued in 1970s
• Due to horrific odor and public outcry
• Dwindling lagoon capacity
Disposal in lagoons – Not a good option
Evolution of Solids Management …
contd.
Evaluated feasibility and economics of three
alternatives:
•
IHS drying on sand beds
• Separate digestion in heated tanks and drying on
sand beds
•
Mechanical dewatering IHS, heat drying & incineration
Adopted the 3rd alternative; built a mechanical
dewatering facility, a heat drying, and an
incineration plant in 1937
Era of Nitroganic Tankage
Sold as:
• Bulk to citrus farmers in Florida
• In bags as Nitrorganic Tankage
Heat drying abandoned in 1981
• Energy shortage in 1979
• O&M costs too high
• Environmental awareness
Era of Nu Earth (1930s – 1987)
Air-dried Imhoff sludge “Give Away”
program
Used in home gardens as a “soil builder”
Public loved it
Promoting Nu Earth
Demise of Nu Earth
Discontinued in 1987 due to:
High metal content – Cd >
>300 mg/kg
Bad press
The District commit to
distribute biosolids only
under controlled practice
“Prairie Plan” Fulton
County, IL - 1971
Using Liquid Sludge For
Reclamation of StripMined Land
Barging Liquid Sludge 200 miles Down
the Illinois River to Fulton County
Won the engineering award of 1974 –
Competition was BART in San Francisco,
CA and Sears Tower in Chicago
“Prairie Plan” Fulton County, IL
No biosolids to site since 2004 because:
Production of air-dried EQ biosolids
Ability to find local outlets for EQ biosolids
Plain economics – Cost savings
Air-dried EQ biosolids readily accepted as topsoil
substitute for daily and final covers in municipal
landfills
Increased local demand for air-dried EQ biosolids
Common Beneficial Uses
Soil Amendment / Soil Conditioner
Improve soil fertility and soil tilth
Substitute for Commercial Fertilizers
Top dressing golf courses
Fertilizing agricultural crops
Substitute for Topsoil
Construction of recreational facilities
Landfill Cover – Daily and final cover
Cinder Ridge Golf Links
Area: 100 acres, 18-hole
course
Quantity = 500 – 600 ton/yr
Savings: >$25,000
Harborside International Golf Course
453-acre site including two 18 hole
courses and golf academy
Over 500,000 dry tons of District’s
biosolids used in final cover of landfill
Hosted Georgia-pacific senior PGA pro
Am and SBC senior open
Voted third best municipal golf course
in USA by the golf week magazine
?
Harborside International Golf Course
Chicago River
Sculpture Park in
Chicago
Area: 4 acres
Application rate = 650 ton/ac
Savings: >$75,000
BIOSOLIDS Utilization SUMMARY
Golf Courses, Parks
(10%)
Landfill
Co-disposal
(3%)
Major Initiatives Undertaken to
Attain Current Program
PFRP-Equivalent Class A Certification
Increase Research and Demonstration
Activities
PFRP-Equivalency Certification
After 1993 the District started evaluating its
solids processing trains for Class A PFRP
Evaluated pathogen analyses of 344 samples
from 1991-1996 monitoring
Filed a petition to USEPA’s Pathogen
Equivalency Committee
Pathogen analysis on additional 1,400 samples
Stickney and Calumet WRPs processing trains
granted Class A PFRP equivalency in July 2002
PFRP-Equivalent Codified Operation
1.Anaerobic Digestion
Temperature – 95ºF minimum
Retention time – minimum 20 days
2.Centrifugation (High Solids Processing Train)
Solids content – 25 to 30 percent
3.Lagoon Aging
Holding time – 18 months minimum after last
addition
4.Air-Drying
Agitation frequency – 3 to 4 times per week
Solids content – 60 percent minimum
PFRP Certification Requirements
Demonstrate compliance by testing 12 samples
per year for helminth ova & virus
Report data semi-annually
Annual PFRP compliance audit
Benefits
Cost of helminth & virus testing for each Project
Eliminates logistics associated with 4-6 wk
turnaround for helminth ova testing
Good PR
Lessons Learned
Good working relationship with state and
federal regulators
Establish good public relations program
Low tech processing trains very effective
in pathogen reduction
Lessons Learned
Codify PFRP-equivalent processing to allow
more operational flexibility
Modify processing trains by blending to with
other materials to address odors, salinity,
and excess nutrients
Air-drying and stockpiling subject to will of
“Mother Nature” and can severely affect
coordinating timing of production and demand
Questions