Problematic solids ground to fine bits
The city of Scotts Valley, Calif., sewage treatment plant was having a very tough and frequent problem with its scum pump. This screw pump would rag up monthly, forcing the operators to take it apart and use large wrenches to manually turn the pump to remove the clogged rags and wipes. This was not a sustainable operating model, and it was costing the city a lot of time, manpower and money, not to mention causing a lot of frustration.
“We had rakes on the clarifier for scum, rags and other problematic debris,” said Troy Adams, wastewater division manager for the city of Scotts Valley. “But we still had such a massive problem with pump clogging. Rags kept getting into the screw pump.”
When the pumps ragged up and could not turn, taking them apart was a constant issue.
“It was an operator nightmare,” said Adams. “It was at least once a week, and at least a four-hour ordeal. It was happening so often, we just left all the tools and everything needed sitting right next to the pump.”
Scotts Valley knew it had to find a solution to this once and for all.
“We spoke to many Franklin Miller users and were very impressed with everything we heard about the Franklin Miller Super Shredder,” Adams said.
Scotts Valley installed the Super Shredder in 2016 on the line from the clarifiers to the scum pit for the fats, oil and grease; rags; and flushable wipes that collect off the top of the clarifiers. The in-line macerator reduces tough wastewater solids to fine bits with a spherical rotor design. The unit is specifically designed for high capacity and minimal head loss. Because of its high percentage of open area, the unit remains practically invisible to flow. It also is simple to install straight through pipe systems.
“From the day we put the Super Shredder online, we have not even one time had to stop operation or de-rag the pump—not a single problem,” Adams said. “The Super Shredder is truly a dream come true for operators. It has saved us so much time. Our maintenance costs alone were so high that this has saved us a ton of money.
“I am so appreciative of the great working relationship with everyone at Franklin Miller, from the salesman to the representative. They were a big help; they worked very closely with me to be sure I was getting the right equipment for my project and that it was being installed and operated correctly for the task I was trying to accomplish. I am very appreciative of all their help, and I will continue to use the expertise and experience in the future with my other projects at the plant.”