System has reduced maintenance times despite lift station's challenging location
In recent years, maintenance operators at the Segerstrom Lift Station in Santa Ana, Calif., noticed an escalation in pump ragging and blockages. This led to an increase in maintenance expenses due to half- to full-day cleanings and an increase in man-hours. Engineers sought the help of Costa Mesa-based JWC Environmental (JWCE), which recommended a Channel Monster sewage grinder.
The pump station was built in the mid-1980s. Since then, the population has expanded and the community now includes a high school, intermediate and elementary school and a business park. Currently, the station runs on a quarterly inspection of the Gorman Rupp pumps and the check valves. The station is also supported by a backup alarm system in case of emergency.
When the Segerstrom Lift Station began filling with more and more polyester-reinforced rags—baby wipes, mop heads and cleaning wipes—it became too much for the pumps to handle. This growing problem clogged the system every other day for 8 to 9 months, and required hours to clear out debris and fix the pumps.
Operators had to break open pump fittings to reach into the problem area and pull the rag balls out of the pump, which contributed to the unbudgeted expense in maintenance. The city needed a sewage grinder that would be low maintenance, protect its pumps upstream and fit its unique setting.
“We had to find a solution,” said Nabil Saba, P.E., acting water manager for the city. “Every time the pumps would clog we had to go in there. It’s a confined space so, not easy. Every time we had to open the pumps and break the seals, and every time the workers are exposed to raw sewage.”
For city engineers, a major challenge was finding a waste grinder that would fit outside their lift station in an upstream manhole. The manhole had a diameter of 60 in. and was under a busy street. Pump station operators knew they needed out-of-the-box thinking to solve this dilemma.
Ige came across JWC Environmental’s wastewater grinders and made the call. He soon realized the company was located right around the corner from the Pump Station. JWCE offered a tour of the factory and a demonstration of their Muffin Monster sewage grinders. The specs on the project seemed to be a challenge; however, JWCE is known for fitting a waste grinder into almost any situation.
In October 2011, a Channel Monster Model 2410 with a max flow of 3.7 million gal per day (591 m3/h) was installed. The sewage grinder has a 5 hp (3.7 kw) immersible motor and now sits beneath a city street deep in a manhole to prevent pump ragging and other debris clogging problems.
The Channel Monster Model 2410 features a dual shafted waste grinder capable of handling a wider variety of solids than a single shafted machine. Counter rotating shafts direct solids toward the center of the waste grinder and three motor options allows precise control and independent operation of the drums and cutter stack.
The manhole, upstream of Segerstrom Lift Station, required special guide rails and easy access to maintain the sewage grinder. JWCE engineers developed a system that would meet all of their needs. The sewage grinder was installed about 18 ft (5 meters) deep in front of the influent pipe. A stainless steel guide rail affixed to the wall of the wet-well—and lifting bail with chain—attached to the modified frame allowed for easy aboveground access to the sewage grinder. No personnel are required to go into the manhole for inspection. The easy access relieved the risk of exposure to wastewater and makes inspections a no-hassle task.
The newly installed system came with automated PLC monitoring and controls. The auto load sensing and reversing reduces any interruptions the flow may bring.
One year later, city engineers report the sewage grinder is doing well and has improved the quality of maintenance.
“It’s been a great piece of equipment to use,” said Brian Ige, P.E., project engineer for the city of Santa Ana. “Outstanding machinery quality.”
When Saba, who has 22 years experience in the industry, was asked how the station has been running since the installation of the Channel Monster waste grinder, his response was, “Fantastic! Our gauge shows no need to go in.”
The city was relieved to find a durable sewage grinder that could not only handle the load but also fit in confined and unique spaces. They are now in the process of considering three more grinders for their other facilities.
For more information, contact JWC Environmental at firstname.lastname@example.org or 949.833.3888.
http://www.wwdmag.com/sites/default/files/imagecache/article_slider_big/Photo%202.jpgThe grinder, custom fitted for the Santa Ana manhole, slides down a guide rail for easy access.
http://www.wwdmag.com/sites/default/files/imagecache/article_slider_big/Photo%201.jpgOperator installs the waste grinder in a tight fit to clear our debris.