Classification of fume purification equipment
  In recent years, with the introduction of a series of emission standards and regulations for the management of cooking oil fume pollution, the state and local governments have stimulated market demand and correspondingly formed a potential market for fume purification equipment for the catering industry.
         Wuxing Environmental Protection Technology can be divided into five categories according to the technical principles of the common fume purification equipment on the market: mechanical fume purification equipment, electrostatic fume purification equipment, wet fume purification equipment, plasma purification method and composite Mechanical method for fume purification equipment.

   1. Mechanical method
         Oil smoke is collected by filtration, cyclone centrifugation, activated carbon adsorption, etc. The processing effect of this treatment method is related to its design, control parameters and materials used. The oil mist is treated by filtration, and the oil smoke particles are separated from the gas flow into the oil tank by inertia and collision by changing the direction of the air flow when the oil smoke passes through the grille, the oil mist net cover, and the like. Most of the filter materials used in the filtration method are lipophilic polymer materials, and the cost is low. The removal rate of the aerosol is 40% to 70%, and the effect on the purification of the odor is obvious. However, the adsorption effect is generally good at the beginning of installation. With the adhesion of oil smoke, the adsorption capacity will gradually weaken, and the filter material must be replaced frequently, so the running cost is high.

        2．High voltage electrostatic method
         The high-voltage electrostatic method is a voltage of 220kv through a transformer to tens of thousands of volts, and then converted into direct current by a rectifier, forming a strong electric field between the two plates, so that the particles in the flue gas are charged, and the charged oil smoke particles are subjected to gravity between the electrodes. Electrode gravitation and wind field dynamics. Since the charge of particulate matter increases with the increase of particle size, large particles are affected by electric field force, and the removal rate of aerosol state pollutants is relatively high, up to 80%~ 90%, Wuxing Environmental Protection Technology with its patented technology, its purification efficiency of soot purification equipment can reach more than 98%. However, the cost of the method is relatively high, and it is relatively simpler in terms of operation and maintenance than mechanical electrostatic type. In general, electrostatic purification equipment is superior to mechanical purification equipment.



        3．Wet treatment
         The wet treatment method is to spray the oil mist with water mist (add some chemical agents to the water to increase absorption), the surface area of the water and oil contact is increased, and the water absorption capacity of the oil smoke is enhanced, thereby achieving the purpose of removing the oil smoke particles. The key to adopting the wet treatment method is the absorption performance of the absorption liquid on the oil smoke. The purification efficiency of the method is high, the temperature of the oil smoke can be lowered, the appropriate chemical reagent can be added, and the pungent taste such as pepper and pepper can be simultaneously removed. However, most of this method will produce secondary pollution. The initial investment is high, power consumption, and frequent water addition. The amount of detergent and absorbent is large, the cost is high, and the washing liquid must be treated. Otherwise, secondary pollution will occur. At present, this method is rarely used in the domestic market.


        4．Plasma purification method
         The use of plasma fume purification equipment has recently been reported on the market. The principle is to use a high-voltage electrostatic method to simultaneously set a plasma field at the front end of the electrostatic field, and use a large amount of active radicals excited by its high energy to degrade the oil mist particles, so that the viscosity is lowered and easy to collect. At the same time as the plasma is generated, the instantaneous high energy generated by the high-frequency discharge can open the chemical bond of some harmful gas and become a single atom or a harmless molecule. According to reports, the technology has a high removal rate, no odor after treatment, and easy maintenance, but the investment cost is high and the technology is not mature enough.

        5. Treatment process selection
         From the current engineering practice of the domestic cooking industry fume treatment, the common treatment process that can fully meet the requirements of China's soot emission is the electrostatic method, followed by the wet method and the mechanical filtration method.
        For large-scale projects with high investment expectations and strict emission requirements, and the impact on surrounding residents should be static equipment, for small and medium-sized catering industry, the processing requirements are high, the investment is not large, and the surrounding residents are not affected. Large, mechanical filtration or wet method can be used.
         For the fume purification equipment market: the combination of the treatment process of electrostatic treatment + water hood and the combination of electrostatic treatment + activated carbon occupies a relatively large proportion in practical applications, and the actual purification effect is also good.