Tests prove filter medium reduces SWRO desalination fouling
Research at the University of Sheffield in the UK is showing that that filters using Disruptor media invented by US company Argonide Corporation is a good solution for reducing the fouling of reverse osmosis (RO) membranes in seawater desalination plants.Disruptor is an electropositive nano-alumina medium invented by Argonide, the manufacture and sale of which are exclusively licensed to Ahlstrom Filtration, USA.
Argonide purchases the medium and fabricates a full line of standard-sized pleated filter cartridges under the NanoCeram® trademark. NanoCeram cartridges are used in diverse applications, including purifying drinking water, removing colloidal iron, bacteria and virus contaminants for industrial and pharmaceutical processing, and in virus sampling of water.
Dr Ibrahim El-Azizi at Sheffield University tested the removal efficiency of Disruptor in a laboratory-scale RO test unit. The results obtained showed that Disruptor can remove the majority of substances that foul RO membranes.
In this study, two types of raw seawaters were filtered through Disruptor, and the results, says Dr El-Azizi "were very interesting". These results will be presented in the AMTA conference in Austin, Texas, USA, in July 2009. Argonide exhibited at the same show last year.
In the coming few months, Disruptor will be tested in real operating conditions using a pilot plant in Libya.
Dr El-Azizi's work complements data previously reported by Argonide in collaboration with Toyota, where NanoCeram® cartridges are being used for protection of RO membranes in recovering and recycling contaminated fresh water in automobile manufacture.
In one Toyota plant, contaminated fresh water was passed through a 5 micron prefilter intended to protect an RO unit. The RO membranes became so heavily contaminated that they needed to be replaced every second or third month. When the 5 micron prefilters were replaced with a combination of a 1 micron depth filter, followed by the NanoCeram polishing filter, the RO membranes remained unfouled for at least one year (and are still running), without requiring any cleaning.
The payback through six months of operation exceeded 5:1, compared with costly membrane replacements, exclusive of savings in improved water yield, elimination of cleaning chemicals and their disposal.
"The highest payback is achieved with a NanoCeram® cartridge that has its own prefilter such as a 1 micron depth filter or a back-flushable 2 micron filter produced by Amiad," says Fred Tepper, co-inventor of NanoCeram/Disruptor and president of Argonide.
For more information, contact Henry Frank, Argonide Corporation
Tel: +1 407 322 2500, Ext 103
Fax: +1 407 322 1144