The Naugatuck, CT merchant sludge incineration facility receives dewatered WWTP sludge from NY, CT, and MA. Originally built in 2002 with PC pumps to provide transport of sludge from a truck receival hopper at grade to a silo located at 80ft elevation, repeated pump breakdowns, blockages, rapid wear and inadequate flow rates forced the removal of the pumps in 2007. An exhaustive investigation into alternative technologies resulted in the selection of SPIRAC vertical conveyors and livebottoms.
The original progressive cavity (PC) pumps were unable to handling the wide range of sludge consistencies and foreign objects (rags, stones, wood, bolts, etc) that inevitably ended up in the imported sludge. The plant was only able to process 3-4 truckloads of sludge per day, and constant blockages and breakdowns contributed to extreme maintenance costs and an unsustainable operation. Furthermore, the piston pumps used to transport dewatered-on-site sludge were also unreliable and prone to high maintenance costs.
Imported sludge is now mixed with dewatered-on-site sludge in the receival bunker and transported to the incineration feed silo. Production today is consistently 12-14 truckloads per day (maximum licensed capacity), with high capacity conveyors only required to run at less than 50% duty.
Over three years of operation, maintenance has been minimal, and downtime eliminated.
