Our Flow Reversal RO (FR-RO) solution is geared to improve system performance significantly when compared to conventional reverse osmosis (RO) desalination systems. Allowing desalination facilities to operate at higher recoveries without exposure to mineral scaling and its negative effects, FR-RO increases process recovery by 10% to 15%, reducing brine volumes required for disposal by up to 60%, and minimizing or completely eliminating anti-scalant chemical consumption.
But how does it work? There are two principles at the core of FR-RO, flow reversal and block rotation. Let's examine these.
#1: Flow Reversal
FR-RO systems operate similarly to conventional RO systems, in which feed flow flows from one direction of the pressure vessel to the other side, continuously. However, while conventional RO has the feed flow moving in only one direction, FR-RO switches the direction of the flow prior to the induction time for scaling. This can prevent scale formation as the induction time depends on the feed water quality. This reversal of the flow, which is enabled by a set of designated valves, exposes membrane elements and generates a "rinsing" effect by re-dissolving any scale that was formed, if at all.
#2: Block Rotation
In a conventional RO system, membranes designated in stages always operate at their stage, whether it's Stage 1, Stage 2 or Stage 3. In FR-RO, the pressure vessels are divided into functional rotating blocks that can periodically operate at another stage. For example, a cluster of pressure vessels, or block, that operate as the first stage may periodically function as the second stage or third. The goal of this principle is to share the burden of a certain block being exposed to supersaturated solutions between all the membrane elements.
With many communities and commercial and industrial facilities seeking optimized treatment approaches, FR-RO is one option that promises increasing process recovery rate, potentially lower capital costs and optimized operational costs. As a high-recovery, low-waste solution, FR-RO may be the ideal approach for treating municipal drinking water and industrial process water, and has already been implemented in projects around the world.