Metropolitan Biosolids Management LLC (MBM} completed construction of the dryer/pelletizer facility in the fall of 2007 at the Stickney Water Reclamation Plant (WRP} located at 6001 West Pershing Road, Cicero, Illinois. Veolia Water NA operates MBM. Cletus Ketter, of Veolia Water NA is the current Vice President of MBM LLC, and over-sees the pelletizing process.

Drying Process Description

Metropolitan Biosolids Management, LLC (MBM} completed construction of a dryer/pelletizer facility in the fall of 2009 at the Stickney Water Reclamation Plant {WRP) located at Cicero, Illinois. The Stickney WRP is part of and operated by the Metropolitan Water Reclamation District of Greater Chicago.

Biosolids produced by the Stickney WRP are anaerobically digested and then dewatered by centrifugation to produce a cake product of 25% dry solids. The MBM facility can process an average of 125 dry tons of biosolids per day to produce an annual total of 45,000 tons of pelletized biosolids. The facility is comprised of four {4} dryers and processing trains. Each train has a maximum capacity of processing 45 dry tons per day, for a total of 180 tons.

 

The MBM facility employs a drying system manufactured by Keppel Seghers. (A process flow diagram is attached.) The Seghers system is a vertical, indirect dryer. Operating in much the same fashion as a clothes dryer, the biosolids are gently moved through the dryer while being heated to cause the evaporation of the moisture remaining in the centrifuged cake. Cake received from Stickney WRP (25% dry solids) is pumped to the top of the dryers where it is mixed with the finished product from the dryers (90-95% dry solids}. The result produces an infeed to the dryer of about 70% dry solids.

Heating takes place as the biosolid pellets cascade across a series of vertically stacked, hollow trays. The trays are filled with heat transfer fluid which has been heated and is then continuously circulated through the trays. As the pellets contact the heated trays, they are heated to a temperature above 215°F. The liberated moisture is removed from the dryers, then condensed and discharged to the Stickney WRP.

The pellets are screened and sized into two size grades (Turf and Agricultural}. Both product grades are cooled and then pneumatically conveyed to storage silos for marketing and distribution

Samples of the biosolids cake coming into the pelletizing/drying facility are being sampled six (6) times per day to monitor moisture content for process control. Pellet samples are also being collected and tested for moisture content six (6} times per day. In addition to moisture content analysis, those

 

samples are being composited and subsequently tested for total kjehldahl nitrogen, ammonia-nitrogen, nitrate-nitrogen, phosphorus, potassium, aluminum, arsenic, cadmium, calcium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, silver, zinc, PCB's, boron, lithium, mercury, and PH.

Pathogen Reduction is achieved through Class A, Alternative 5 of 327 IAC 6.l-4-13(b)D. Monitoring is being done to demonstrate compliance with this regulation. The facility utilizes a proven drying process that has demonstrated effective pathogen reduction at eleven other facility sites. Daily samples are collected, composited and analyzed for compliance. The testing is being conducted by a certified laboratory and proper sampling, shipping, storage and analytical techniques are being utilized.

Vector attraction reduction is achieved through 327 IAC 6.1-4-15(b)7 with the stabilized biosolids being dried to a solids content of 75% or greater. The pelletized biosolids produced at the Stickney WRP by MBM consistently test above 90 percent dry solids. Metropolitan Biosolids Management LLC (MBM}