What types of membrane separation equipment? What is the application of membrane separation technolo

The membrane separation experimental equipment mainly includes several types:

1. Tubular device. With a tubular membrane and supported by a porous tube, it constitutes a device similar to a shell-and-tube heat exchanger, which is divided into internal pressure type and external pressure type, and each is supported on the outer or inner side of the membrane by a porous tube. The internally pressured membrane surface is easy to rinse and is suitable for microfiltration and ultrafiltration.

2. Plate-and-frame device. Between sheet stacks of the same size, separators are inserted in phases to form a flow channel for two streams. Since the stack can be placed in a uniform electric field, this structure is suitable for electrodialyzers.

Plate-and-frame units can also be used for ultrafiltration and dialysis where the hydrostatic pressure difference between the two sides of the membrane is small.

3. Hollow fiber device. Hollow fibers do not need support and can withstand high differential pressures, and in various membrane separation equipment, it has a large membrane area per unit equipment volume. A device similar to a shell-and-tube heat exchanger is constructed from hollow fibers.

The hollow fibers are about 1mm in diameter, juxtaposed in millions of pieces, and the ends of the fibers are sealed with epoxy resin to form a tube sheet, which is encapsulated in a pressure vessel. The hollow fiber type is suitable for reverse osmosis and gas permeation separation.

Membranes are materials that have the function of selective separation. The process of separating, purifying, and concentrating different components of the feed liquid by using the selective separation of the membrane is called membrane separation. It differs from conventional filtration in that membranes can be separated at the molecular scale, and this process is a physical process that does not require phase changes or additives.

The pore size of the membrane is generally micron-level, according to the difference in its pore size (or called molecular weight cut-off), the membrane can be divided into microfiltration membrane, ultrafiltration membrane, nanofiltration membrane and reverse osmosis membrane, according to the different materials, it can be divided into inorganic membrane and organic membrane, inorganic membrane is mainly only microfiltration level membrane, mainly ceramic membrane and metal membrane. Organic membranes are made of polymer materials, such as cellulose acetate, aromatic polyamide, polyethersulfone, polyfluoropolymer, etc.

The main applications of membrane separation technology include the following:

1.Microfiltration membrane equipment Membrane pore size", working pressure about 300kpa. It can be used to separate fine particulate matter (<15 m) and coarse dispersed phase oil beads in sewage or as a pretreatment for other treatment processes.

2.Ultrafiltration membrane equipment Membrane pore size, working pressure of 150 700kpa. The ultrafiltration membrane equipment can separate fine particulate matter (10 m) and emulsified oil in sewage. Useful substances (e.g. from electroplating paint waste, polyvinyl alcohol in the chemical fiber industry); When used in advanced sewage treatment, it can remove macromolecules, colloidal organic substances, viruses and bacteria.

3.Nanofiltration membrane equipment Membrane pore size, operating pressure of 500 1000kpa. The nanofiltration membrane equipment can intercept organic compounds with a relative molecular weight of 200-500, which is mainly used for the separation of multivalent ions and chromaticity particles in sewage, and can remove 2 3 salinity, 4 5 hardness and more than 90% of dissolved organic carbon and THM precursors in secondary effluent.

4.Reverse osmosis (RO) membrane pore size <, operating pressure. Reverse osmosis removes not only salts and other substances in the ionic state, but also organic matter, colloids, bacteria, and viruses.

5.Electrodialysis is suitable for the treatment of high salt concentration water with a salt content of 500-4000mg L, which can remove ionized inorganic salts in the water.

Membrane separation technology is applied to the concentrated extraction of enzyme preparations.

1. Microfiltration membrane separation equipment.

In view of the separation characteristics of microporous membranes, the application scope of microporous membranes is mainly to intercept particles, bacteria and other pollutants from the gas phase and liquid phase to achieve the purpose of purification, separation and concentration.

The specific fields involved are: pharmaceutical industry, food industry (gelatin, wine, liquor, fruit juice, milk, etc.), high-purity water, municipal sewage, industrial wastewater, drinking water, biotechnology, biological fermentation, etc.

2. Ultrafiltration membrane separation equipment.

Early industrial ultrafiltration was used in wastewater and wastewater treatment. Over the past 30 years, with the development of ultrafiltration technology, ultrafiltration technology has been involved in many fields such as food processing, beverage industry, pharmaceutical industry, biological preparations, traditional Chinese medicine preparations, clinical medicine, printing and dyeing wastewater, food industry wastewater treatment, resource development, environmental engineering and so on.

3. Nanofiltration membrane separation equipment.

The main application fields of nanofiltration include: food industry, plant deep processing, beverage industry, agricultural products deep processing, biomedicine, biological fermentation, fine chemicals, environmental protection industry ......

4. Reverse osmosis membrane separation equipment.

Due to the advanced, efficient and energy-saving characteristics of reverse osmosis separation technology, it has been widely used in various sectors of the national economy, mainly used in water treatment and concentration of heat-sensitive substances, and the main application fields include the following: food industry, milk industry, beverage industry, plant (agricultural products) deep processing, biomedicine, biological fermentation, preparation of drinking water, pure water, ultrapure water, seawater, brackish water desalination, electricity, electronics, semiconductor industry water, pharmaceutical industry process water, preparation water, water for injection, Sterile and non-pyrogen-free pure water, process water, boiler water, washing water and cooling water for food and beverage industry, chemical industry and other industries.

5. Miscellaneous. In addition to the above four commonly used membrane separation processes, there are also dialysis, controlled release, membrane sensors, membrane gas separation, etc.

Membrane separation technologies mainly include the following: microfiltration, ultrafiltration, nanofiltration, reverse osmosis, and pervaporation.

1. Microfiltration - commonly used in food and medicine disinfection, purification of liquids in semiconductor production industry, biotechnology, wastewater treatment, etc.

2. Ultrafiltration - often used in milk skimming, protein pre-concentration, juice clarification, fermentation broth treatment, discharge liquid treatment, etc.

3. Nanofiltration - can be used to remove oligosaccharides, dyes, multivalent ions, etc.

4. Reverse osmosis - it can be used to treat municipal wastewater, industrial wastewater, seawater and brackish water desalination, groundwater and surface water treatment.

5. Pervaporation - Pervaporation - Pervaporation is also known as pervaporation evaporation, which refers to a membrane separation method in which the components pass through the membrane and evaporate at different rates under the action of the vapor partial pressure difference of the components on both sides of the membrane, so as to achieve the purpose of separation. The organic pervaporation membrane uses the adsorption-dissolution mechanism of the membrane layer to the components, and the molecular sieve pervaporation membrane uses the adsorption-diffusion and molecular sieve mechanism of the membrane layer on the components. Applications include dehydration of organic solvents, removal of organic matter from aqueous solutions, and separation of organic matter from organic matter.

Membrane separation equipment is a large-scale mechanical equipment manufactured in the production plant in accordance with the technical parameters of membrane separation by using membrane separation technology, and its equipment can play the role of separation, and the effect is far beyond the traditional separation method.

The core technology of membrane separation equipment is membrane separation technology, the separation membrane is a material with selective separation function, the working principle is the principle of physical and mechanical screening, and the separation process is the process of using the selective separation mechanism of the membrane to realize the separation between different components of the liquid or the concentration of active ingredients.

The difference between membrane separation technology equipment and traditional filtration is that the membrane can be selectively separated within the molecular range, and the cross-flow operation process of the membrane can solve the problem of pollution blockage, which is a scientific and advanced separation technology and process.

The process application and development of membrane separation should be based on the characteristics of the material system and the process requirements, combined with experiments to carry out scientific verification, while solving the problem of material refining, it is also necessary to ensure the feasibility of the process, and is suitable for industrial clean production as the standard.

Equipment used for a series of membrane separation operations such as ultrafiltration, reverse osmosis, gas permeation separation, dialysis, electrodialysis and liquid membrane separation. Due to the unique characteristics of membrane configurations and separation processes, there are also many types of equipment. Sometimes according to the purpose or use of the process, they are called ultrafilters, osmometers, dialyzers, electrodialyzers or desalinations, etc., and their future development trends are automation and simplicity.

Membrane separation equipment is used in the following areas:

Application of membrane separation technology in advanced treatment of urban sewage.

Application of membrane separation technology in industrial wastewater treatment.

Application of membrane separation technology in drinking water treatment.

Application of membrane separation technology in seawater desalination.

Application of membrane separation technology in brackish water desalination.

The application field of membrane separation equipment is generally mainly used in water treatment, chemical production, food industry and other related fields, especially in the water treatment process of industrial water treatment, industrial circulation, cooling water purification and other related production processes.

Application of microfiltration ceramic membrane: The application of ceramic membrane is mainly to intercept particles, bacteria and other pollutants from gases and liquids, so as to achieve the purpose of purification, concentration and separation.

The field of equipment application is still relatively broad, like some sewage treatment plants, they are using this kind of treatment equipment. There are also limbs digging some gas pollution control, which also needs to use this equipment.

Application field The specific fields involved in microfiltration mainly include: pharmaceutical industry, food industry (gelatin, grape group wine, liquor, fruit juice, cow burning milk, etc.), high-purity water, urban sewage, industrial wastewater, drinking water, biotechnology, biological fermentation, etc.

Ultrafiltration: Early industrial ultrafiltration should be used for wastewater and sewage treatment in leather or socks. Over the past 30 years, with the development of ultrafiltration technology, ultrafiltration technology has now involved food processing, beverage industry, pharmaceutical industry, biological preparations, and traditional Chinese medicine.

The methods of membrane separation are:

1.Microfiltration: Refers to the retention of particles or solubles larger than that.

The pressure drives the process of the plate.

2.Ultrafiltration. Right: refers to the process by which particles or solubilities smaller than 2 nm are trapped in a pressure-driven membrane.

3.Nanofiltration: A pressure-driven membrane separation process (particles less than 2 nm) between reverse osmosis and ultrafiltration

4.Reverse osmosis: Using a highly permeable film as the separation medium, the solvent in the solution can penetrate the film when the osmotic pressure of the solution is exceeded, and the solute and insoluble matter are intercepted in front of the membrane.

Membrane separation technology is a new technology for separation, purification, and concentration with high efficiency and energy saving without phase change at room temperature. Its basic principle is that it can use natural or synthetic films with selective permeability to separate, classify, purify or enrich two-component or multi-component systems with external energy or chemical potential difference as the driving force, and can be used in both liquid and gas phases.

For liquid-phase separation, it can be used in aqueous solution, non-aqueous solution, aqueous sol system, and aqueous solution system containing other particles. Most of the separation membranes are solid (most of the current membrane materials are organic polymers), but they can also be liquids. What they all have in common is the ability to selectively transmit to the systems they separate.

Below, Dramayler introduces you to the characteristics of common membrane separation technologies.

According to the type of membrane, it can be divided into microfiltration, ultrafiltration, reverse osmosis, nanofiltration, dialysis, electrodialysis, osmotic gasification and gas separation.

Introduction to the characteristics of common membrane separation technologies:

1) The membrane separation process does not undergo phase change, and the energy consumption is lower than that of separation methods with phase change and other separation methods.

2) The membrane separation process is carried out at room temperature, so it is especially suitable for the separation, classification, concentration and enrichment of heat-sensitive substances, such as juices, enzymes, drugs, etc.

3) Membrane separation technology is not only suitable for the wide range of separation of organic and inorganic substances, from viruses, bacteria to particles, but also for the separation of many special solution systems, such as the separation of macromolecules and inorganic salts in the solution, the separation of some azeotropes or near-boiling point substances, etc.

4) Because only pressure is used as the driving force of membrane separation, the separation device is simple, easy to operate, easy to control and maintain.

Biofilm is a thin layer of biological colonies formed by microorganisms on the surface of fillers or other attachments, which is essentially a microbial flora, which is formed by microorganisms in the process of oxidizing nutrients in water. For example, if the basin at home is filled with water and excavated for a few days, there will be a thin, slimy layer of dirt on the inner wall of the basin, which is the biofilm. Its main role is to oxidize and decompose nutrients in water (or transfer some nutrients from water to living organisms), but it does not have a filtering effect.

It is mainly used in the biochemical treatment of sewage.

The membrane in the membrane equipment separation equipment is a polymer composite material, which plays a filtration role, and in terms of filtration accuracy, there are microfiltration membranes, ultrafiltration membranes, nanofiltration membranes, and reverse osmosis membranes, and the filtration accuracy is getting higher and higher, and the reverse osmosis and nanofiltration membranes can already filter ions.

They are all membranes and generally should have separation performance, the membrane of membrane separation equipment mainly has two kinds of polymer organic membrane and inorganic membrane, according to the different membrane pore size, it can be divided into ultrafiltration, microfiltration, nanofiltration, reverse osmosis, etc., the biological film is not much of the dust-based solution, but it should also have a separation function, such as the human body pie guess detoxification or something, very sharp and many are with membrane function.