WATER & WASTEWATER MANAGEMENT
PROTECTING CRITICAL MEMBRANE SYSTEMS
Automated scraper strainers pre-filter water and wastewater to protect fragile membrane systems from damage caused by large, suspended particles, reducing maintenance and replacement costs
C
hemical processors rely heavily on membrane filtration technology to ensure consistent water quality, raw material recovery, and
recycling when manufacturing acids, alkalis, fertilisers, inks, paints, coatings, soap, detergents, toiletries, perfumes, explosives, glues, and essential oils. Te industry also uses membrane filtration to desalinate, diafilter and purify dyes, pigments and optical brighteners; concentrate and dehydrate minerals; clarify caustic agents; produce polymers and recuperate metals. In additional, valuable raw materials in process water such as silica, paints, dyes, inks, catalysts, surfactants and precious metals can be recovered prior to reuse or disposal. Te challenge is that membrane systems are delicate and can be easily damaged by large particulates in the water. A pre-filtration step eliminates this risk by removing oversized suspended solids to prevent damage, eliminate unnecessary maintenance, and reduce the cost of premature membrane replacement. Among the pre-filtering options
available, automatic self-cleaning scraper strainers are increasingly popular because they are affordable, require very minimal maintenance or attention, and can remove solids down to 75 microns. Te strainers allow for continuous, uninterrupted flows even during blowdown cycles. When compared to filters that must be manually cleaned or even conventional backwash systems, automatic scraper strainers can save substantial costs on maintenance and membrane replacement.
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INDUSTRIAL WATER TREATMENT AND MEMBRANE SYSTEMS
Although various filtration methods use membranes, the most mature is pressure driven membrane filtration, which relies on a liquid being forced through a filter membrane with a large surface area. Depending on the size and type of the particles involved, the process could be categorised as reverse osmosis, nanofiltration, ultrafiltration or microfiltration.
In general, reverse osmosis is used
to produce potable water or deionised water. Nanofiltration is used in wastewater treatment as well as by the petrochemical industry to purify gas condensates, and the chemical industry for solvent recovery. Ultrafiltration and microfiltration are increasingly used in water and wastewater treatments. In industrial applications, water treatment is also vital to protect
An Acme scraper strainer in situ
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