Redefining Silica Limits in High-Recovery RO/NF
Silica scaling is one of the biggest obstacles to achieving high recovery in RO and NF membrane systems, often causing reduced performance and frequen..
Preventing Iron Fouling in a Brackish Water RO System
A municipality restored stable long-term performance and eliminated the need for frequent cleanings by introducing a novel iron-control antiscalant...
Validation of a Method for Modelling Brine and Permeate pH in RO and NF Systems
A reliable method for predicting concentrate and permeate pH values is essential for accurately predicting operation and maintenance (O&M) costs i..
The Perils of Using Chloramines for Pretreatment of Water Reuse RO
The use of chloramines has become a standard pretreatment method for biofouling control in water reuse RO. When used in the 2 – 3 ppm range, chl..
Validation of an Arsenic Rejection Computer Model for RO/NF Membranes
Arsenic contamination in groundwater supplies has long been a problem, and membrane technology is among the efficient methods for its removal for prov..
A Novel Calcium Carbonate Scaling Model for RO Systems
Calcium carbonate is the scale RO plants run into most often, and for decades the industry has leaned on old rules of thumb (the LSI and CCPP indexes)..
The Impact of Ferrous Ion Oxidation on Silica Scaling in RO Systems
A 6-million-gallon-a-day RO plant in South Texas started chlorinating its water to remove arsenic, and unintentionally created a worse problem. The ch..
Controlling Aluminum Silicate Formation in Membrane Separation Processes
When silica scales an RO membrane, aluminum is almost always mixed in. This study shows that even trace aluminum reacts with silica to trigger heavy s..
An Evaluation of Corrosion Control Additives for Potable RO Permeate
Many drinking-water plants spend heavily on corrosion inhibitors that don’t actually work, leaving them with “red water” complaints ..