If you have an open-channel UV system with a modulating gate actuator for level control, you’ve likely experienced problems. In this setup, the actuator must maintain proper water level above the bulbs. Otherwise, low water levels can cause bulbs to overheat and high levels can interfere with proper disinfection standards. Additionally, downtime can result in lost treatment capacity.

ON THE HUNT

Historically, a multiturn electric actuator is used with a weir gate on the effluent side of a channel for regulating water levels. However, these actuators are not rated for modulating service and tend to exhibit problems. It’s common for electric actuators to hunt for proper level control setpoints, thereby swinging flows and creating problematic level control. Seizures and electrical failures are also common.

ADDRESSING ISSUES

UV system providers and consulting engineers have therefore moved toward the use of a ballasted flap gate, which does not exhibit automation, or fixed weirs, which add footprint to the plant designs. These solutions do not address the root cause, which is having a reliable actuator that can regulate water levels.

TRUE SOLUTIONS

REXA provides reliable and accurate control of UV effluent level control gates, maintaining water level setpoints and meeting disinfection standards while prolonging bulb life. With REXA, plants can seamlessly balance flows across multiple UV channels, regardless of flow condition.

REXA is an industry leader in actuator design and technology. In the past 20 years, the company has become a major international supplier of control valve actuators and damper drives. 

508/584-1199 • www.rexa.com