Reverse osmosis and nanofiltration

Company "Water Technology Engineering" uses reverse osmosis technology for partially demineralized water.

Reverse osmosis - an efficient process for producing partially desalinated water. From an economic point of view, the most effective use of technology in the salt content of the water source of more than 300 mg / l. The water obtained from reverse osmosis is used to fill and top-up the cooling circuit, feeding steam boilers for manufacturing processes in various industries. Reverse osmosis is also used for the preparation and / or purification of drinking water and process water the food industry.
The driving force of the reverse osmosis is applied external pressure. The amount of energy required for reverse osmosis separation, is directly proportional to salinity solution.

Chem greater salt content, the greater the specific energy consumption for desalted water. As a result, source water passage is formed along the membrane two streams, one passing through the membrane - the permeate (partially desalted water), and the rest - concentrate (concentrated solution starting salts). Permeate extraction percentage varies from 30% (desalting sea) to 80% (desalination of brackish water). To increase the yield of permeate necessary to use additional reverse osmosis to concentrate.

For efficient and continuous operation of the reverse osmosis plant source water must be removed suspended solids, colloids, strong oxidizing agents. Therefore, the original water must undergo pretreatment. The ideal solution is to use ultrafiltration pretreatment technology or mechanical filtration followed by ultrafiltration. High quality feedwater ultimately significantly increases the efficiency of the membrane elements, extend the life and reduce operating costs.

Modern reverse osmosis membranes are made of chemically resistant material, in particular polyamide. A wide range of varieties of polyamide and ways to obtain it possible to create a large range of reverse osmosis membranes. The selectivity of the membrane varies from 85% (nanofiltration) to 99.8% (desalination of sea water and saline industrial effluents). The range of membranes and their configuration can achieve virtually any desired performance of desalinated water from any salt source water quality.

Benefits

Compared with conventional methods desalination, reverse osmosis has many advantages:

• It does not require a large amount of consumption of reactants (acid, alkali);

• It is a continuous process;

• compact system saves production space and is more ergonomic than other desalination systems;

• process can be easily automated;

• the perfect solution for desalination complex salt composition of water;

• convenient way to source water for desalination methods deep: electrodeionization, mixed bed filters;

• reduces the content of organic substances (Chemical Oxygen Consumption, Biochemical Oxygen Demand, etc.).