first membrane technology used only in research areas that are typically enough for the process of innovation.The volume of consumption was small, the cost is high, narrow range of consumers.Then the membrane technique has been applied in space research and defense industries.The consumption increased, production has become smarter, the cost of the membranes decreased, and made possible their use in industries such as medicine, pharmacology, and others. A further decline in membrane materials led to increased production volume of the product and the beginning of its application in industries with significantproduction, such as the food industry.A worseni
cost of the membrane is determined mainly by the material from which it is made, and the complexity of the process.For fine filtration (ultrafiltration, reverse osmosis high and low pressure) are commonly used membrane materials of the following: a mixture of cellulose triacetate with cellulose acetate (CTA), polyamide (thin layer semipermeable membrane - TLC), modified polysulfone (SPSF).
CTA membranes are relatively inexpensive and have a high specific productivity.Can work steadily in the range of pH = 5.8, which in some cases reduces the scope of their use.The material used has a high resistance to contaminants resulting from the chlorination of water, which makes the use of these membranes in water treatment.
TLC Membranes have a low thermal capacity and are used in a wide range of pH values.They are used in various fields, especially for filtration at low temperatures and low pressures, at a pH greater than 9.0.However, this type of membranes the most costly.
SPSF membranes are useful for softening the water with high pH or high concentrations of nitrates in those cases where a water purification membrane can not handle other types.
At the end of 1970 in the western market were ceramic ultrafiltration membranes that are based on carbides and oxides of several metals.From polymer membranes distinguishes them more chemical, mechanical and thermal stability.Control widespread use of ceramic membranes is due to their high cost (it is 3-5 times more expensive than the polymer).Therefore, to date, leading positions in many areas occupied by membrane filtration polymer membranes.Ceramic membranes are used only in those areas where they are indispensable, e.g., in the purification of certain types of industrial waste waters.
All these materials are used to manufacture the membranes of various shapes - sheet, folded, rolled, and in the form of hollow fibers.Such form is mainly determined by a number of technical problems, the main of which is to increase the filtering area to enhance the performance of the membrane element.
mainly world market membranes formed by products of famous companies from Western countries and Japan.To date, the release of membrane materials are not an independent branch, their manufacturers are part of the companies with a broader product range.Thus, the corporation Film Tec (USA), a leading manufacturer of reverse osmosis membranes, was founded in 1977, but in 1985 became part of the chemical and pharmaceutical company Dow Chemical.Currently, Film Tec specializes in the production of membrane materials for use in industry, municipalities, home.
other major manufacturers of membranes from the United States - Osmonic.This company started its operations in 1969, moving to market the device using reverse osmosis technology tangential flow Crossflow.In 2003, she also became a member of the world's largest group - General Electric - and was named GE Osmonic.Today, the corporation is engaged in equipment for water purification, water treatment for power plants, boilers and boiler and treatment of municipal wastewater.In addition, there is a company Osmonic Inc.(USA), which is engaged in the development of water treatment technologies, producing desalinated water and wastewater treatment.
Another recognized leader in the manufacture of membranes for water purification - Hydranautics (USA).This firm was founded in 1963 in California and one of the first (1970) started the production of membranes for reverse osmosis.In 1987 the company merged with the Corporation Nitto Denko (Japan), the largest player in the market of polymers.The assortment includes Hydranautics membranes for drinking water, water for heat engineering, wastewater treatment, desalination of sea water.The company produces rolled reverse osmosis elements of improved performance (ESPA series and LFC) and selectivity (series CPA).
in the world well-known companies membrane Koch-Glitsch GmbH (Germany) and Koch Membrane Systems Inc.(USA).Their factories produce tubular and spiral hollow fiber membranes for reverse osmosis.
largest manufacturers of membranes in the Far East - already mentioned Nitto Denko Corporation and Toray Inc.(Japan).
Note: In recent years, the market appeared newcomers oust somewhat leading players.They focused on the production of more simple in terms of technology of materials - mainly for household appliances.This manufacturer has not yet afford to release membranes, such as the desalination of sea water or cleaning up waste.
main supply membranes in Russia are carried out by the production of a number of Western European companies as well as manufacturers from the United States.
In practice not the membrane, and the membrane modules that are mounted in a water purification system.The manufacturers of these membrane modules use their own production or buy them from other manufacturers.Currently, there are about hundreds of major manufacturers of membrane modules, and about half of the membrane and release.
In our country also has a number of fairly major manufacturers of polymeric membrane materials and modules.These should include JSC "Vladipor" (Vladimir), produces a wide range of sheet and roll membrane elements.In the manufacture of the replaced roll element enterprise uses polymer membranes polysulfonamide.
manufacturing polysulfone membrane in the form of hollow fibers carries GP VNIIPV (Mytischi, Moscow Region.);SRI "Crystal" (Dzerzhinsk, Gorky region.) Produces tubular membrane.Next to domestic research and production companies mastered the production of track membranes.In our country are made and ceramic membranes.For example, the NGO "Keramikfiltr" () produces tubular membrane type KMFE and SPC "Ultra" - sheet-metal.
Among manufacturers of membrane water treatment equipment can be noted, for example, "media filter" and "National Water Resources" (both) and the company "Vladistat" (Vladimir).
When using membrane modules there are a number of restrictions that are caused by high sensitivity to contamination of the membrane.To reduce the degree of contamination of the membrane to provide a system for pretreatment of water, and to prevent contamination using various techniques, e.g., use of turbulence-nets between membranes.
Nevertheless, the membrane in the process sooner or later, "clogged" and lose their ability to filter.For further operation they must be either cleaned or replaced.Based on this situation, manufacturers of membrane technology specializing in the production of chemicals and equipment to restore the membrane or in the production of replacement filter elements.
basically interchangeable elements are used in residential post-treatment, local water treatment plants and water supply stations in large industrial facilities, and provides system restore membrane modules.For manufacturers and trading organizations is preferable to work with replaceable membrane elements.
quality and price
as membranes is determined not only by their hydraulic performance, mechanical, thermal and chemical stability, high productivity and selectivity, but also, most importantly, the ability to keep these parameters constant throughout the entire lifetime.There are certain parameters and quality in the manufacture of the membrane modules.
modules must also possess a number of properties: legkozamenyaemostyu treatment systems, the strength of the housing, tight fastening, large filtration surface to provide the necessary filtration rate, the lack of dead zones.
Practice shows that at the beginning of operating parameters can be the same in the membranes of a wide range of manufacturers.But to produce durable membrane with characteristics corresponding to the best examples for the entire service life, the strength is not all producers.And even a significant reduction in the price of membrane modules can not compensate for the deterioration of their quality.
prices membranes and membrane modules in the Russian market dictate the world's leading manufacturers, and although they affect its specificity.
view of the fact that the life of the membrane filter element is small compared with the period of work of other filtration equipment, the price is somewhat high.
membrane materials market is very dynamic.With the increasing number of exploited membrane plants growing sales of membrane filter elements.There are many companies engaged in the supply, installation and commissioning of filtration equipment.The vast majority of such equipment purchased under the order and stock virtually no stored.
At the same time for the uninterrupted supply of consumer replaceable membrane modules having a small lifetime, needed permanent representative trade organizations, which have their own storage space.Several years ago, the market there are certain difficulties in the regular supply of consumables and replacement membrane modules.But now we have a system service, which provides periodic replacement exhaust elements.
In addition, for the Russian market characteristic features associated with the sale of replacement parts that do not require service specialists.We are talking about reverse osmosis filters for household drinking water purification.These plants are used membrane performance 150-250 l / day.Obviously, the development prospects of this sector are very large membranes, as a potential buyer of such products is every family.
As already mentioned, the direct production of membranes and membrane modules are mainly concentrated in the US, Western Europe and Japan.They account for over 90% of total production.At the same time, these regions and consume about 75% of its production.
Indicators Russian market is much more modest, but its prospects are not bad.Unfortunately, the factors constraining demand for membrane equipment necessary to carry relatively low income mass market, which is sometimes just refuses to water purification systems.