ACCESS TO NEW BIOSOLIDS TECHNOLOGY THROUGH PRIVATIZATION

The Metropolitan Water Reclamation District of Greater Chicago's (MWRD) Stickney Water Reclamation Plant is a 1200 MGD (4.54×106m3/d) secondary treatment plant serving a mostly combined sewer area of 260 square miles (4.11×105ha) with a population equivalent of 5.5 million persons. The facility produces approximately 140,000 dry tons (127×106kg) of biosolids per year; the majority of the air-dried solids at this facility are EQ. These biosolids are beneficially used for agricultural and silvicultural purposes; as soil amendments and supplements and as daily and final cover for municipal waste landfills.The MWRD's current sludge processing practices are essentially anaerobic digestion, centrifuging or lagooning, and air-drying. Centrifuging and air-drying are limited by climatic conditions, particularly during the winter months. It was decided that a mechanism for processing a portion of the plant's biosolids production that would not be weather dependent would increase flexibility and reduce costs for the existing methods. Many of the existing operational methods were necessarily performed during extended shifts with the concomitant increased costs. A technology that is independent of weather would also relieve the problems associated with moving biosolids from the centrifuge facility to the drying beds during winter months.In order to access some proprietary processes/equipment, MWRD elected to pursue a D/B/O/O/F facility with a contract period of 20 years. This paper will describe the format of the Request for Proposal, the bidding process and the results of the effort. Costs, terms and other information for the contract will be provided.