Common equipment for oil fume purifiers

Use a simple hood to collect oil fumes, and exhaust the oil fumes outdoors through an exhaust fan. It only collects oil fume without purification treatment, and the oil fume removal rate is 0.

2. Water fume hood

Using alkali as a detergent, it contacts the oil fume through spraying to purify the oil fume, and then collects and discharges it through an exhaust fan.

The oil fume removal rate of this product is about 90-98. The oil fume removal rate meets the requirements of the oil fume emission standard for catering industry gt; GB18483-2001.

3. Water spray scrubber purification process

Using a fume hood to collect and send it to the absorption tower (spray, sieve plate, filler) for purification, and then discharge it through an exhaust fan.

The oil fume removal rate of this product is about 80-90%. The oil fume removal rate meets the requirements of GB18483-2001. However, the equipment installation space is large and the system is complex.

4. High-voltage electrostatic (plasma)

Use gas ionization and electric field force under high pressure to charge dust particles and separate them from the gas.

The oil fume removal rate of this product is nominally 95%. The oil fume removal rate in the first week of product use is 95%, which meets the requirements of GB18483-2001. After about 3 months of continuous use, the removal rate plummets until it reaches zero. If you need to ensure the oil fume purification effect and the oil fume removal rate meet the standard, it must be cleaned every two weeks. A professional electrostatic oil fume purifier cleaning service company can do it for you, and the cost ranges from 1,000 to 5,000 yuan each time. If it is not cleaned according to the specifications, there will be serious oil accumulation in the exhaust pipe, and the risk of fire will be great.

5. Physical filtration

One or a combination of wire mesh, activated carbon, and steel wire.

The oil fume removal rate of this type of product is actually 20 to 30, and it cannot meet the requirements of GB18483-2001 when used alone. Easy to clog and needs to be cleaned weekly.

6. Photocatalysis

Use ultraviolet light to decompose the oil mist of oil-containing gas.

The oil fume removal rate of this product can reach 90%, which meets the requirements of GB18483-2001. The premise is that a pipeline of at least about 30 meters long is required to facilitate the installation of ultraviolet light tubes. Currently, only imported UV tubes can guarantee product reliability and durability. The disadvantage is that ultraviolet light causes cancer and must be sealed tightly. If it leaks, it will not do anyone any good. By the way, if it leaks a little, it can be sterilized and disinfected.

7. Biological purification

Use oil-loving microorganisms to decompose and purify the oil mist in oil fume.

The oil fume removal rate of this product can reach 90%, which meets the requirements of GB18483-2001. A specialized microbial pool is required, and microbial metabolism requires regular processing and renewal. This treatment method is the most environmentally friendly.

8. Liquid foam washing

Using the mass transfer double membrane theory, a combination of physical and chemical methods, mechatronics products, strictly speaking, should not be called oil fume purifiers, but should be It is more reasonable to call a fume purifier.

The oil fume removal rate of this product can reach 90%, which meets the requirements of GB18483-2001. Using a special purifier to improve the double-membrane mass transfer power between the gas and liquid phases, it can quickly capture oil smoke and other particles in the gas phase; at the same time, the negative pressure of its own exhaust fan is used to generate a liquid foam layer of about 600mm thick (liquid foam size and diameter 1.5mm) for scrubbing purification of oil fume gas. Approximately equivalent to the purification effect of a 600-meter natural rainfall layer. The removal rate of oil in lampblack is 90%, the removal rate of black smoke particles is 90%, the removal rate of dust and other impurities in the air is 90%, the removal rate of various odors is 70%, and the removal rate of blue smoke (chemical gel) is 60%. The product needs to be drained and professional purifiers added every 2 to 3 days of use. The product has stable operation, long service life and special grade fire protection.

1. Fume hood scrubber process

2. Fume hood electrostatic process

3. Mixed water hood electrostatic activated carbon process

4. Fume hood photocatalytic purification

5. Liquid foam washing For oil fume purification, the oil fume purification and treatment technologies currently on the market include mechanical separation method, catalyst combustion method, activated carbon adsorption method, fabric filtration method, wet treatment method and electrostatic treatment method.

1. Mechanical separation method

Use the inertial collision principle or the cyclone separation principle to separate oil fume.

Disadvantages: The baffle filter is easy to break, and the waste is directly discharged; requires regular maintenance and maintenance; the vertical angle of installation should be less than 15°; the purification efficiency is not high, and is only suitable for pretreatment or purification efficiency requirements. low occasions.

2. Catalyst combustion method

The principle of the combustion purification method is to use the heat generated by high-temperature combustion to carry out oxidation reactions to convert pollutants in the oil fume and exhaust gas into substances such as CO2 and H2O , so as to achieve the purpose of purification. During the combustion process, the oil fume exhaust gas passes through the self-purification catalyst, and the catalytic reaction of the catalyst is beneficial to the conversion of pollutants. Generally, ceramic or metal honeycombs are used as carriers for oxidation catalysis. This type of oil fume purification equipment is only suitable for situations where the oil fume concentration is very low, such as eating raw food or making semi-finished products.

Disadvantages: The development of catalytic combustion purification equipment is not yet very mature.

3. Activated carbon adsorption method

Use granular activated carbon or activated carbon fiber felt to absorb pollutant particles in oil smoke. The characteristics of this equipment are similar to those of filtration and purification equipment, but it is better at removing odor molecules from oil smoke.

Main disadvantages: The cost of activated carbon is high.

4. Fabric filtration method

The oil fume exhaust gas first passes through a certain number of metal grilles, and large particle pollutants are intercepted; then after passing through filter materials such as fiber mats, the particulate matter is diffused , intercepted and removed. The filter material usually used is a polymer composite material with high oil absorption performance. This kind of equipment has low investment, low operating costs, no secondary pollution, and easy maintenance and management; but it has the disadvantages of large resistance, large area, and the need to frequently replace the filter material. The purification efficiency is generally 80~92.

Disadvantages: Due to the high resistance of the filter material, such as the pressure drop of the purifier with glass fiber filter material, which can reach 1500Pa, and the filter material needs to be replaced frequently, the application of filtration purification equipment is limited.

5. Wet treatment method

Use water or other detergents to form a water film by spraying with a nozzle, and the water mist absorbs the oil smoke. The fume particles are in contact with the water mist and water film sprayed from the nozzle. After mutual inertial collision, retention, diffusion of fine particles and mutual agglomeration, they flow down with the water droplets, thereby separating the fume ions from the air flow. This kind of equipment has simple structure, low investment, small area, low operating cost and convenient maintenance and management.

Disadvantages: high resistance, low purification rate of sub-micron particles, and secondary pollution of oily sewage.

v l The purification efficiency of mechanical separation and purification equipment is not high, and it is only suitable for occasions with low pretreatment or purification efficiency requirements;

l Wet washing and purification equipment has a low purification efficiency for sub-micron particles. The purification rate is very low, and the generated washing liquid needs to be processed;

l Filtration and purification equipment requires purification and replacement of filter materials, which consumes a lot of energy; the cost of activated carbon adsorption and purification equipment is too high;

l The development of catalytic combustion purification equipment is not yet very mature;

l Electrostatic purification efficiency equipment is increasingly showing its advantages with its high purification efficiency, low pressure drop, stable operation, and convenient maintenance and management. superiority, the current market share is close to 90%.

6. Electrostatic treatment method

Under the action of an external high voltage, electrons are emitted from or near the surface of the metal wire of the negative electrode and move rapidly toward the positive electrode, colliding with gas molecules and ionizing them. When the oil fume exhaust gas passes through this high-voltage electric field, the oil fume particles are charged due to collision and captured gas ions in a very short period of time, and move towards the positive dust collecting plate due to the force of the electric field, thereby achieving the separation effect. This kind of equipment requires less investment, occupies a small area, has no secondary pollution, and has low operating costs.

Because it is easy to capture dust with smaller particle size, the purification efficiency is high, reaching 85~95. The difference between its purification mechanism and the gas method is that the separation force is electrostatic force, which acts directly on the particles rather than on the air flow, so it has the characteristics of low energy consumption and small resistance.

Electrostatic filter: When gas containing dust particles passes through the high-voltage electric field formed between the cathode line connected to the high-voltage DC power supply (also known as the corona electrode) and the grounded anode plate, the cathode Corona discharge occurs and the gas is ionized. At this time, the negatively charged gas ions move toward the sun plate under the action of the electric field force. They collide with the dust particles during the movement, causing the dust particles to be negatively charged. Under the action of the electric field force, the dust particles also move towards the anode. After reaching the anode, the electrons they carry are released. The dust particles are deposited on the anode plate, and the purified gas is discharged out of the dust filter.

Technical advantages of high-voltage electrostatic equipment:

1. Large processing air volume and small pressure loss. Can operate in high humidity conditions.

2. The removal rate in one pass can meet the purification requirements.

3. The particle diameter range effectively removed is large.