Increase Efficiency and Cuts Costs.
The chief engineer at one of the buildings at Rockefeller Center in New York City recognized that in addition to the cost of maintenance and overtime, they were spending over $21,000 annually for pit cleaning, odor control and enzyme treatment to soften solids of a sewage pit.
The sewage pit at One Rockefeller Plaza had a build up of extremely heavy solids laying on top of the water and grease had accumulated on the walls. Although they were using vertical shaft sewage pumps as a duplex system with actuator style ball floats for level control, there was no real logic for controls. The pumps constantly failed from clogging and required chronic attention. The check valves had been replaced several times due to rags caught on the flapper and the gate valves had failed due to wear.
GA Fleet provided a Duplex Flygt Submersible Sewage Pump system using model NP 3127 10 HP submersible pumps, each with a Flygt mix flush valve for suspending solids in the wet well. We provided state-of-the art, simple to operate controls with a unique Fleet control methodology for removing surface solids and preventing the build up of grease ring. All the functionality of a sewage pump station are built into the controller: off, lead, lag, high alarm, low alarm and alternation. The levels are now completely field-adjustable and no longer require entry to the wet well.
To facilitate installation, Fleet provided a unique FPS SubRig pipe and valve assembly. The SubRig is a pre-engineered, modular submersible pump piping system. Fully integrated with the frames and covers, and the electrical connection system, the SubRig readily facilitates installation and uses components of better quality than industry standards.
Engineers throughout NYC are now specifying SubRigs on new installations, and many experienced plumbing contractors request them as well.
With the retrofit of the wet well, the building has achieved a more efficient and far less tasking system than before, and has gained savings on the life-cost of the equipment with minimal maintenance.