发布日期：2019-07-23 15:49 浏览量：
Formation of cooking fume
Oil, organic matter and other products which are decomposed or broken by heating during cooking and processing. It is a mixture of gases, solids and liquids produced by a series of reactions of edible oil and food at high temperature, commonly known as lampblack. Oil fumes mainly consist of alkanes, fats, esters, alcohols, ketones, aldehydes, heterocyclic amines, polycyclic aromatic compounds and mutant sources. Influencing public health and human health are also very harmful. Oil fume has certain effects on human lung and respiratory tract. There are cytogenetic toxic substances in oil fume that can cause different biological effects, which are characterized by carcinogenic mutation and reduce human immune function.
2. Calculation of cooking fume exhaust
According to the standard design specification of kitchen ventilation, smoke collecting hood should be installed on the top of cooking kitchen utensils, and the amount of smoke discharged from ventilation project should be designed according to the cross-section wind speed of smoke hood 0.5-0.7m/s.
According to Q = 3600V. S.
Q：排烟量—m³/h V：截面风速—m/s S：集烟截面—㎡
Q: Smoke Emission - m_/h V: Sectional Wind Speed - m/s S: Smoke Collection Section
The cross-section wind speed is designed as 0.6, i.e. the smoke exhaust volume per square metre of the hood cross-section.
Q=3600×0.6×1 =2160 m³/h
3. Target of Fume Control and Low Altitude Emission Requirements for Catering
1. Target of Restaurant Fume Control
The smoke emission export meets the emission requirements of "Fume Emission Standard for Catering Industry" (GB18483-2001) and achieves the emission standards.
2. Requirements for Low Altitude Emission of Catering Fume
Under rated air flow, the purifying efficiency of oil fume purification equipment should be more than 95%.
In urban residential and commercial areas, the emission requirements of cooking fume are generally more stringent. The exterior walls of buildings can not be installed with air ducts, but can only be discharged at low altitudes. Even if the fume emission meets the emission requirements of the "Fume Emission Standard for Catering Industry" (GB18483-2001), people may be complained about the fume disturbance. Therefore, the purification efficiency of the fume purification equipment is relatively high. Under rated air flow, the purification efficiency needs to be more than 95%.
IV. Design of Governance System
1. Design process and process
According to the characteristics and engineering requirements of cooking oil fume in kitchen frying pan, the advanced high-voltage electrostatic purification technology of Hangzhou Zhengying Environmental Science and Technology Co., Ltd. is adopted in the treatment, and the process design is customized according to the actual situation.
2. Working Principle of Electrostatic Catering Fume Purification Equipment
The electrostatic cooking fume purification equipment of Zhengyi Science and Technology uses electrons emitted from cathode in high voltage electric field and negative ions produced by electrons colliding with air molecules to capture cooking fume particles, make cooking fume particles charged, and then use the electric field to make the charged cooking fume particles adsorbed by the anode, so as to achieve the purpose of removing cooking fume. Yes. Because the diameter of electrons is very small, the particle size of electrons is much smaller than that of soot particles. Moreover, the density of electrons in the electric field is very high (up to 100 million/cm3), which can be said to be ubiquitous. The soot particles in the electric field are easily captured by electrons (i.e. charged). The charge of soot particles in the electric field is an inevitable phenomenon that follows a certain mechanism, rather than a simple occasional collision. Theoretical analysis: including electric field charge and diffusion charge. Electric field charging is due to the relative dielectric constant of soot particles greater than 1. In electric field, the power line around soot particles changes, which makes the power line intersect with the surface of soot particles. Ions moving along the power line inevitably collide with soot particles and transfer charge to soot particles. Diffusion charging is the movement of ions in air due to heat. Diffusion, when approaching dust particles, produces an electric image force that attracts and charges each other.
The design of electric field makes the soot particles move at a lower speed. Generally, within a few seconds of zero, the soot particles can be charged with enough charge. The charged particles will be affected by electric field force (Coulomb force) in the electric field. The result is that the soot particles are adsorbed to the anode. Therefore, the rate of oil fume removal by electric degreasing is very high, and it is especially suitable for capturing oil fume particles with smaller particle size and lighter weight.
In the electrostatic cooking fume purification equipment, the electric power is mainly used to emit electrons and promote soot particles, which has little effect on the air, so the energy consumption of the electrostatic field is small. Besides, the resistance of the degreasing equipment is also small, and there is no need to use a fan with high pressure. Therefore, the total energy consumption of electrostatic oil fume purification equipment is smaller than that of other methods of oil fume removal.