Dexter City Council is moving forward with a plan to replace a key piece of equipment at the Wastewater Treatment Plant.
Public Services Superintendent Dan Schlaff presented a preliminary report to council that estimates $266,000 will be needed to replace a blower and aeration at the treatment plant. The blower provides air flow during the treatment process – critical for supplying sufficient oxygen, keeping bacteria suspended and adding flocculation.
Regulations require the plant’s blowers to run at 1,000 standard cubic feet per minute.
“About the last two years we’ve had to run on two blowers,” Schlaff said. “If we have one more blower go down that’s going to put us out of compliance.”
The treatment plant currently has three blowers, including the broken one. Those three all operate at 500 standard cubic feet per minute. The new blower will operate at 1,200 standard cubic feet per minute, putting the plant more than what the state requires.
The three blowers were originally purchased in 1999 – 16 years ago – and have an average lifespan of 20 years.
Schlaff added that the new blower will also be better for the plant’s employees.
“There’s a safety factor that’s in there that we don’t currently have on the floor,” he said.
The new blower is equipped with a pressure relief valve that relieves excessive pressure from closed discharge valve or excessively clogged diffusers – a function the current blowers do not have.
The new blower would also potentially be able to save the treatment plant energy, according to Schlaff’s report.
“New blower would have a variable frequency drive (VFD) to adjust the air output (and power usage) to match actual aeration needs,” he wrote. “The blower could be connected to a Programmable Logic Controller (PLC) tied to the dissolved oxygen probes in the Aeration Tanks in the future to further reduce energy usage.”
City council approved F&V Operations to move forward with a design plan during it’s regular meeting Sept. 24.