Algae growth on launder trough and weir surfaces is a continuous operations and maintenance problem in treatment plants everywhere. At its most benign, algae is an unsightly nuisance that requires frequent cleaning by plant personnel. This is a costly, never-ending process that robs valuable time of maintenance personnel. Unchecked, algae growth can also disrupt weir overflow, clog filter screens and pump mechanisms. In plants equipped with UV disinfection systems, algae in the effluent may significantly reduce the systems’ effectiveness and cause serious maintenance issues. 

NEFCO’s patented Launder Cover Systems are designed to inhibit the growth of algae on the launder trough and weir surfaces by blocking sunlight from striking those areas. Without sunlight, algae is largely eliminated, constant cleaning by maintenance personnel is a thing of the past, and the threat of downstream equipment problems caused by floating algae is minimized.

The Weir Wall Configuration overcomes these problems:

1. The Cover opens away from the operator, providing an unobstructed view of the launder and weir and the operator can access the trough if necessary.
2. The Cover is mounted over the Weir Wall on adjustable stainless steel brackets, so alignment is independent of tank wall variations.
3. The Cover latch/handle is located immediately in front of the operator. This is a rugged, spring-loaded mechanism that locks the Cover closed but opens easily.
While NEFCO offers both cover configurations, the Weir Wall Mounted Cover is the choice of most plants. The Weir Mount section is secured over the weir wall with stainless steel brackets. The hinged Cover Section arches over the trough and rests on a cover support flange fastened to the tank wall. Alternate panel units feature a molded tab that seals the panel seams from sunlight.

NEFCO offers cover systems for a variety of clarifier trough configurations, including inboard, outboard, radial, peripheral feed and others. In addition, NEFCO has developed a number of custom patterns for opening the covers, including alternate, sequential and unrestricted.

Each Cover panel is manufactured of tough uv-protected fiberglass, specifically designed to withstand the rigors of both the application and the environment. The Cover System is custom engineered to the specific configuration and dimensions of the clarifier for optimum performance and ease of installation. Once installed, unlike “brush” or “sweep” systems, the Cover operates 24/7/365, requires virtually no maintenance and has no parts to wear and be replaced.

NEFCO has been granted a number of US patents for its Launder Cover System designs.