Gillian Chew

Filter Flow Control The filtration process removes suspended particles from water by passing the water through a medium. After a period of run-time, a filter needs to be “backwashed” to remove the captured particles from that run-period. Particle capture rate is important in ensuring filtered water contains no micro-organisms that could be harmful to people. Micro-organisms can be difficult to disinfect/remove from water, so operators measure the turbidity of water to gauge the capture rate of a filter. Ideally, an efficient filter runs the longest and captures the most particles (has the lowest turbidity).  In a traditional gravity fed filtration system, the most critical valve application is the effluent control valve (commonly a butterfly valve). This valve typically sits at the bottom of the filter where it controls the rate of water flow moving through the filter. Commonly, accurate modulating control of filter flows with this valve is imperative to maintaining a constant, stable flow in a filter. The more stable the flow, the greater the capture rate. Surges in flow can occur when flow rates are not stable, which can allow suspended matter to pass through the filter – effectively increasing the turbidity of the filter effluent.  REXA  Linear  and  Rotary  Actuators have a history of success in the water treatment industry with controlling filter effluent valves. Maintenance-free operation of these modulating valves over decade-long periods is common. More importantly, the position accuracy of REXA  Linear  and  Rotary  Actuators (dead-band as tight as 0.05) can modulate a filter effluent butterfly valve disc in very finite increments that eliminate hunting. Precise position accuracy will stable flows through a filter, allowing for more efficient particle capture and lower turbidity.  Literature Download the Filtration Filter Effluent Control Application Spotlight! Webinar Download

Water Storage REXA has a history of providing solutions for water storage applications. Some of our customers have sought the modulating capabilities of REXA to accurately meter flows into and out of their water storage infrastructure. Others have required the reliability and fail-safe capabilities of REXA for applications used to protect the stored water during emergency conditions. In either case, REXA has the product and experience to help you

Ozone Control Controlling a gaseous service via a butterfly valve with any degree of accuracy is 100% dependent on the positioning of that butterfly disc. On small valves sizes common in the ozone treatment process, the position accuracy is even further emphasized, and the slightest movement of a butterfly disc can result in significant flow changes. The positioning accuracy of REXA Linear and Rotary Actuators truly shines on this service, as the dead-band accuracy (as tight as 0.05%) can position butterfly valve discs in small enough increments to promote accurate flow control, improving the ozone treatment process efficiency.

Raw Water Influent Flow Control Reliable control of  incoming flows is very important to starting the wastewater treatment process off on the right foot. Incoming flows are being modulated, any flow swings due to actuator hunting can cause upsets further along in the treatment processes. For this service, it is more important that the actuators are reliable, in order to avoid any possible disruption to the desired incoming flow rates. REXA has a history of offering both reliable and accurate flow control for this important service

Water Distribution For agencies or municipalities seeking to modulate flows in their water distribution, REXA  Linear  and  Rotary  Actuators can delivery accurate flow control over many years of maintenance free service.