Title
Resolution to Approve the Purchase of Polymer from Polydyne for Centrifuges at the Wastewater Treatment Plant (not to exceed $141,750.00)
Memorandum
Your approval is requested to authorize the purchase of up to 15,000 gallons of polymer from Polydyne for the City’s Wastewater Treatment Plant (WWTP) at a unit cost of $1.05 per pound and a total estimated cost of $141,750.00.
New centrifuges installed under the Residuals Handling Improvements Project (RHIP) were put on-line in December 2010 and are currently processing all of the biosolids at the WWTP. Polymer is an essential chemical used with the new centrifuge equipment to process and dewater WWTP biosolids.
During the pilot testing phase of the RHIP, ten different polymers were initially screened and two of them, Polydyne C-9530 and Degussa K290, were selected and extensively tested to assess their functionality to dewater Ann Arbor biosolids. Based on the results of the pilot test, the Polydyne polymer was proven to provide the best performance for dewatering and achieved the highest percent solids. Consequently, the Polydyne polymer was used to implement equipment start-up in December 2010 and is currently being used to process all WWTP biosolids.
The WWTP needs up to an additional 15,000 gallons of polymer to finish the current dewatering season, December 2010 through April 2011. Based on its performance during the study and start-up phases of the RHIP, the Polydyne polymer is the appropriate choice for this season. The Polydyne polymer is a proprietary specialty chemical which can only be purchased from SNF-Polydyne Inc. Use of another polymer may impact equipment performance, performance testing and release of equipment from the Contractor to the City, and is not recommended at this time.
WWTP staff will conduct additional polymer testing at the end of the current dewatering season, April or May 2011, which is when the land application season begins and the centrifuges are available for pol...
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