Title
Approving the procurement of repair and rebalancing services for a wastewater treatment plant dewatering centrifuge to GEA in the amount of $80,241.87 and authorizing the City Manager to execute the same.
Summary
The City’s Central Wastewater Treatment Plant currently has 2 operation centrifuges that are used for dewatering final biosolids to produce a solid that can be disposed of properly and to remove as much water as possible from the final sludge. These centrifuges are designed to run at a very high speed to pull the water away from the sludge slurry which produces a sludge cake that is roughly 20-25% solids content. Due to the high speed at which these centrifuges operate and the frequency at which they operate, it is considered a good business practice to have the rotating assemblies sent out to be rebalanced and refurbished every 5 years.
During FY2021, City Council approved a spare rotating assembly to be purchased which would allow for staff the ability to remove the rotating assemblies when they need to be sent to be rebalanced without having any negative operational consequences by having one of the centrifuges gone for an extended period of time and therefore allow staff to be able to properly follow best practices for the units. After the spare rotating assembly was delivered and installed, staff had one of the centrifuges that has been operating for longer than 5 years sent in to GEA to be rebalanced and to be inspected for any repairs that may need to be done. After GEA was able to break down the rotating assembly, they were able to provide the City with a quote for the rebalancing and necessary repairs to the unit so that staff could keep the rotating assembly on the shelf to be installed when the next assembly needs to be sent in for rebalancing. The goal is to have the 3 assemblies in rotation through the rebalancing process so that staff can continue to operate effectively and efficiently while also minimizing both down time an...
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