Ultrafiltration device is a kind of pressurized membrane separation technology, and a pressure active membrane. Under the action of external force (pressure), processed material enter the membrane element through which colloids, particles and substances with higher molecular weight in the water will be intercepted while water and small solute particle permeate through the membrane, thus equivalent liquid of permeation outflow through the membrane. When the processed water flow through the membrane surface at a certain flow rate by virtue of external pressure, solute with hydrone and molecular weight less than 300 to 500 but particles and macromolecule larger than membrane pore are intercepted by screening, thus realizing the purpose of purifying water. In other words, when water passes through ultrafiltration membrane, most of colloids and large amount of organics in the water will be removed. In order to guarantee the recoverability of membrane performance, make sure to remove retentate from the membrane parts and therefore, it is required to conduct back flushing regularly and take other measures to remove sediments on the membrane surface and restore the membrane flux.
Advantages of ultrafiltration technology over traditional separation method
1. As ultrafiltration process is conducted under normal temperature, no component is destroyed under mild conditions. So this technology is specially suitable for separation, grading, concentration and enrichment of thermosensitive substance, such as medicine, enzyme and juice.
2. Considering the filtration process has no changes, there is no need to heat or add chemical reagent. It is an energy-saving environment-friendly separation technology, low in energy consumption and with no pollution.
3. With high separation efficiency, ultrafiltration technology is very effective for recycle of micro constituent in dilute solution and concentration of low-concentration solution.
4. As the ultrafiltration process only uses pressure as the power to drive membrane separation, the separation device is simple and convenient to operate, easy to control and maintain and short in process.
5. Ultrafiltration method also has certain limitation. For example, dry powder formulation can’t be acquired directly through this method, and for protein solution, only 10-50% concentration can be realized.
Application fields
○Pretreatment of reverse osmosis feedwater
○Advanced treatment of large and medium-sized drinking water plant
○Municipal and industrial waste water treatment
○Recycle and purification treatment of circulating sewage
○Recycle of useful substance in sewage
○Preparation of mineral water, sterilization treatment of drinking water and well water
○Sterilization, clarification, purification and separation of oral liquid and biological products
○Terminal treatment of ultra-pure water
○Concentration and separation of juice, protein and enzymic preparations