By Greg Reyneke, MWS In the water quality improvement industry, membranes are defined as physical barriers that separate solutions and allow passage of waterborne contaminants within a certain range of size, molecular mass, or even charge polarity strength. When driving pressure is applied and, depending on the material, pore size and … [Read more...]
Water Treatment—An Enigma of Its Own, Part 2
By Peter S. Cartwright, PE In Part 1, I addressed the wild claims and nonsensical science behind PWCs designed for scale control. This article is devoted to other water quality improvement claims of these and other PWCs. These claims include disinfection or microorganism reduction, biofilm prevention/removal, TDS reduction, change in … [Read more...]
Membrane Separation—More than Just RO
By Greg Reyneke, MWS Membrane separation is finally reaching a level of general acceptance as the powerful tool that it is for residential, commercial and industrial water treatment. Most dealers and users know about reverse osmosis separation technology, but there are other technologies that you need to know more about. Membranes are … [Read more...]
Membrane Separation and Filtration: Tried and True Technologies
By Alan Murphy Introduction In reverse osmosis and nanofiltration membrane separation processes, membranes act as barriers against the normal hydrodynamic flow of water, thereby filtering liquids that contain high dissolved solids. This unique cross-flow filtration pattern separates solids out of water without the … [Read more...]
On-Site Bottled Water Testing
By Michael Neiheiser Editor's Note: In view of the increased need for ensuring water quality, this article by Michael Neiheiser is a good reference for all involved in bottling water. Continuous assessment of water quality is necessary to ensure a safe and consistent bottled water final product. This is the … [Read more...]
A Look at the Present and Into the Future of Potable Water Treatment
By Peter S. Cartwright, PE Introduction Water. Along with air, it is one of the two most critical components for life. This discussion is focused on water, how it is used, abused and taken for granted. Also, it’s one person’s prediction of the future and primarily, it is devoted to drinking water. Without water in our … [Read more...]
California Drought Prompts Innovative Water Reuse for Highway Construction
by John Meland Background The San Diego Freeway (I-405) in southern California is one of the most congested freeways in Los Angeles County, carrying more than 300,000 vehicle trips daily on some sections. The area population is expected to grow 11 percent by 2040, significantly increasing traffic volume on the freeway. … [Read more...]
Executive Insight: H2O International’s Ivan Molina on Water Purification and Survival Expeditions
By Denise M. Roberts H2O International, Inc.’s Iván Molina Castrillón is a multifaceted, multitalented man with a zest for learning, life and business. It is just these character traits that make for a successful and enterprising employee. This story, about Nature and company-sanctioned pursuits of Molina, give a … [Read more...]
Water Matters: Update on NSF/ANSI 419 Public Drinking Water Equipment Performance – Filtration
In January, this column introduced a new draft standard from NSF in the area of water treatment. When the column was written in early December 2014, NSF 419 Public Drinking Water Equipment Performance–Filtration was undergoing the ballot process to become an NSF standard and subsequently an NSF/ ANSI standard. Since then, the ballot process has … [Read more...]
A New Technology for Arsenic Removal
Numerous articles have been and continue to be written about the current methods for removing arsenic from drinking water. It is not the purpose of this article to rewrite what has already been written but rather to introduce a new material and method for removing arsenic. This article will present the existing technologies in brief format, … [Read more...]