Reverse Osmosis Filter

Microfiltration is a purification procedure which eliminates pollutants from a fluid (liquid & gas) by passage via a microporous membrane layer. A common microfiltration membrane pore dimension range is 0.1 to 10 micrometres (µm). Microfiltration is essentially different from reverse osmosis and nanofiltration because those techniques use pressure as a means of forcing water to go from low pressure to high pressure. Microfiltration can use a pressurised process but it does not require to include pressure.

Engineered by Professor Richard Adolf Zsigmondy at the University of Göttingen, Germany, in 1935, membrane layer filters were first commercially developed by Sartorius GmbH a few years later. Membrane layer filters found instant application in the area of microbiology and in particular in evaluation of safe drinking water.

Additional progress of microfilters in the mid-1970s led by the United States Food and Drug Administration requirement for non-fibre delivering filters to be employed in the manufacturing of injectable solutions. Microporous membranes are utilized by the micro-electronics business as an essential component of water production. Membrane filters are extensively applied in biotechnology and food and beverage programs where sterile merchandise is required.

Progressively used in drinking water treatment, it efficiently eliminates major pathogens and pollutants such as Giardia lamblia cysts, Cryptosporidium oocysts, and substantial bacteria. For this application the filter has to be rated for 0.2 µm or less. For mineral and drinking water bottlers, the most generally employed format is pleated cartridges typically created from polyethersulfone (PES) media. This media is asymmetric with bigger pores being on the exterior and smaller pores being on the inside of the filter media.

Microfiltration membranes were first released to the municipal water treatment market in 1987 and used primarily to waters that were fairly easy to handle. These were cold, clear source waters that were vulnerable to microbial contamination. Low pressure membranes were chosen to get rid of turbidity spikes and pathogens without chemical conditioning.

As low pressure membranes improved in approval and acceptance, customers started to use the technology to more difficult waters which contained more solids and higher levels of mixed organic substances. A few of these waters required chemical pretreatment, such as pre-chlorination. These changes in water quality induced change in low pressure membrane technology. New solutions and processes were released to deal with higher solids and chemical compatibility.

Process: Microfiltration is the procedure of filtration with a micrometre sized filter. The filter systems can be in a submerged configuration or a pressure vessel configuration. They can be worthless fibres, flat sheet, tubular, spiral wound, hollow fine fiber or track etched. These filters are permeable and permit water, monovalent varieties (Na+, Cl-), blended organic matter, small colloids and viruses through but do not permit particles, deposit, algae or large bacteria through.