Comarco Industrial’s Bar Screen & Screw Press Installation:
Non-dispersibles Problem Solved for Moody, Alabama
Background: Moody, Alabama is situated fifteen miles east of Birmingham and is one of the fastest growing communities in the state with a current population of 14,000. The homes connected to sewer are served by a 0.75 MGD wastewater treatment facility. Two 50 hp no-clog 3-inch pumps convey the influent flow from the 38-foot deep wet well to one of two identical treatment trains in the facility.
Problem: Moody was experiencing significant volumes of domestic flushable wipes, towels and other non-dispersible material in its collection system and treatment facility. Prior to working with Comarco Industrial, these non-dispersible items passed through the poorly functioning manual 2-inch bar screen, through the influent pumps and into the plant. Rags plugged pumps, interfered with the influent wet well level sensor, hung up on weirs and clogged RAS and other sludge lines throughout the facility. Operators removed rags from aeration basin weirs daily; they unclogged sludge lines three to four times weekly. The accumulative cost to the utility was in the tens of thousands of dollars in maintenance repairs, equipment replacements and labor.
Solution: Comarco Industrial designed a screening installation utilizing an FB Procédés NG21 Automatic Vertical Bar Screen and an FB Procédés VCP150 Screw Press with an automatic bagging system at the influent pump station of Moody’s treatment facility. After only weeks of operation, ragging of weirs and sludge lines is virtually non-existent.
“We can tell the plant is already working better,” says David Treadwell, Vice-chair of the Moody Sewer Utility Board. “Visually, it’s a cleaner process.”
The FB Procédés bar screen, designed at 3/8 inch for the Moody facility, effectively and efficiently removes non-dispersible material at the headworks where it is automatically conveyed to the FB Procédés screw press. The screw press compresses the screenings into 30 to 35% dry material, dropping it into a 4-yard dumpster for disposal.
“It’s amazing dryness,” says Treadwell of the compressed screenings, “and [the screw press] packs it up pretty tight.”
Results: “We have no rags whatsoever after this [equipment installation]. This piece of machinery solved it,” says Treadwell of the plant-wide ragging problem.
“We also anticipate lower effluent BOD values,” adds Bob Terrell, operations supervisor, “but it is still too soon to tell.”
The plant staff in Moody, Alabama is pleased with the project’s success.
“We are very satisfied,” emphasizes Treadwell. “As a matter of fact, I can say the equipment performance has exceeded our expectations”