The importance of proper water treatment is often underestimated by oil companies and engineering companies. We consider that filtration is critical for water injection and that well water must generally be filtered to eliminate certain impurities which will have significant impact on the performance of the water treatment facilities. Filter systems must be able to eliminate shells and algae as well as other contaminants present in the fluid.
The rating always depends on the impurities it must eliminate, but commonly high-flow filtration of 2μm will be sufficient for this application. Ölof Filtration Teknologerna AB also recommends in most cases automatic self-cleaning back flushable screen filters previous to the sulphate removal process.