What Is Magnetic Separation?

Magnetic separation technology is a technology that processes substances in magnetic fields. The application of this technology has penetrated into various fields. Magnetic separation uses the magnetic properties of impurity particles in wastewater to separate them. For non-magnetic or weakly magnetic particles in water, magnetic inoculation technology can be used to make them magnetic. With the help of external magnetic field, magnetic suspended solids in wastewater are separated out, so as to achieve the purpose of purifying water.

Magnetic separation technology

Right!

Magnetic separation technology is a technology that processes substances in magnetic fields. The application of this technology has penetrated into various fields. Magnetic separation uses the magnetic properties of impurity particles in wastewater to separate them. For non-magnetic or weakly magnetic particles in water, magnetic inoculation technology can be used to make them magnetic. With the help of external magnetic field, magnetic suspended solids in wastewater are separated out, so as to achieve the purpose of purifying water.

Chinese name

Magnetic separation technology

Technical characteristics

Memory effect

Function

An emerging water treatment technology

Advantages

Fast wastewater treatment and large capacity

Equipment advantages

Small size, simple structure, low cost, etc.

In recent years, magnetic separation has become an emerging water treatment technology. As a physical treatment technology, magnetic separation has obtained many successful applications in water treatment, showing many advantages. Magnetic separation uses the magnetic properties of impurity particles in wastewater to separate non-magnetic or weakly magnetic particles in water. Magnetic separation technology is a technology that processes substances in magnetic fields. The application of this technology has penetrated into various fields.

The magnetic field itself is a kind of field with special energy. The water or aqueous solution treated by the magnetic field has its optical properties, electrical conductivity, dielectric constant, viscosity, chemical reaction and surface tension and adsorption, cohesion and electrochemical effects. The characteristics all produce measurable changes, and when the magnetic field is removed, the changes can be maintained for hours or days, with a memory effect.

Because of these phenomena, magnetic technology has been a research hotspot for many years. Magnetic separation technology is a technology that applies magnetic field processing to materials. The application of this technology has penetrated into various fields. This technology uses the difference in the magnetic sensitivity of elements or components to magnetically process materials with the help of external magnetic fields to achieve enhanced An emerging technology for the separation process.

With the advent of strong magnetic fields and high gradient magnetic separation technology, the application of magnetic separation technology has gone from separating strong magnetic large particles to removing weak magnetic and diamagnetic small particles, from the initial mineral separation and coal desulfurization to industrial water treatment From the separation of magnetic and non-magnetic elements to the separation of homogeneous mixture components of diamagnetic fluids. As a clean and energy-saving emerging technology, magnetic separation will show attractive development prospects.

They can be made magnetic using magnetic seeding techniques. With the help of external magnetic field, magnetic suspended solids in wastewater are separated out, so as to achieve the purpose of purifying water. ^[1]

1.High efficiency of magnetic separation technology

The technology has the advantages of fast wastewater treatment, large processing capacity, and is not affected by natural temperature. It has strong separation ability for ultrafine suspended solids and low-concentration wastewater that are difficult to remove by other separation methods. In particular, the filtration speed of the high-gradient magnetic filter separator is 10 to 30 times that of the high-speed filter used for general processing, which is equivalent to 100 times that of the sedimentation tank.

2.The magnetic separation equipment is small in size, simple in structure, easy to maintain, low in cost and small in area.

Such as high gradient magnetic separation equipment, easy to realize automation; highly reliable work, moderate maintenance; small footprint, taking ordinary quick filters as an example, the magnetic filter covers only 1/6 of its area, and the amount of civil construction is also very small. Greatly shorten the construction cycle. Therefore, the magnetic filter is particularly suitable for small and medium-sized water plants and cities with tight land resources.

3. The high gradient magnetic filtration method can be used to remove those pathogenic microorganisms, bacteria, and some difficult-to-degrade organic substances with strong drug resistance and toxicity.

Studies have shown that magnetic field forces can inactivate or inactivate water and enzymes in pathogenic microorganisms, bacteria, and other cells, so that they are killed and removed by magnetic filtration without generating harmful by-products. Compared with chlorine or chlorine preparation disinfection, the magnetic separation technology does not produce organic matter in wastewater that reacts with chlorine to produce trihalomethanes (THMs) and other halogenated hydrocarbon compounds, which are the causative factors of various diseases.

4. Relatively low operating costs

For small and medium-sized water plants, compared with the traditional process (filter part) using magnetic filter treatment device (filtration part), the increased operating cost (consideration of iron powder during operation and recovery rate of 80%) is 0.49 yuan / m3 (the test equipment is individually customized and the cost is much higher than mass production), but the magnetic filter can remove organic matter in water much better than the traditional process, and can remove algae. The quality of the effluent water is better than that of the sand filter.

The magnetic separation technology has the following technical difficulties and limitations in treating wastewater:

1. The residual magnetism of the medium makes it difficult for the magnetic separation equipment to flush the magnetic particles adsorbed by the magnetically concentrated medium when the system is backwashed, thereby affecting the work efficiency of the next cycle.

2. In order to improve the magnetic field gradient, it is necessary to select a high-magnetism saturation magnetic-gathering medium. The selection of the magnetic-gathering medium has certain technical difficulties and increases the operating cost.

Although magnetic separation technology is a simple and feasible water treatment technology with high treatment efficiency, due to the above technical difficulties and limitations, it needs to be studied and overcome. Therefore, it affects its wide application in practical applications.

Compared with conventional methods such as sedimentation and filtration, the magnetic separation method has a series of advantages such as large processing capacity, high efficiency, low energy consumption, and simple and compact equipment. It has not only been successfully applied to blast furnace gas washing water, steelmaking soot purification of wastewater, Purification of steel rolling wastewater and sintering wastewater, and in other industrial wastewater, municipal wastewater