With the acceleration of China's urbanization process, the residential volume rate of Chinese people is increasing, 99% of the urban residential in China is multi-storey or high-rise buildings. For high-rise residential users, daily cooking time will encounter a problem: the smoke is not smooth.
Whenever the cooking rush time comes, the public flue will be concentrated in a large number of smoke, resulting in the flue gas pressure increased, so it will form a flue congestion and oil fume intrusion and so on.
Chinese cooking characteristics: stir-fry oil Fume more Chinese cooking in various forms, stir-fry is the most common form of cooking, the smoke is the most. Fry generally include hot pots, oil, hot oil, under the food, stir fry, seasoning and serve the steps, and produce the largest amount of smoke for the next ingredients, stir fry and out of the pot. Cooking fume particulate matter can be divided into two categories: the first type of mechanical dispersion (explosion pot) produced by the sedimentation of particles, will be deposited to the ground, do not cause persistent pollution of the atmosphere; The second category is the particulate matter produced by the volatile condensation of oil, which is in the presence of a floating state in the air between 0.01-1.0 microns,
Belong to the typical PM2.5. Fume gas contains carbon monoxide, carbon dioxide, nitrogen oxides, as well as a strong carcinogenic propylene aldehyde, benzene and pyrene, and many other seriously harmful substances. The oil fume's agglutination is adsorbed on the skin, can cause the cell chromosome damage, accelerates the skin aging. Fume can not only cause skin problems, but also to our health has adverse effects, such as loss of appetite, depression, upset, fatigue and other symptoms, medical known as ' Lampblack syndrome '.
The kitchen fume is called ' Invisible Killer '. According to the WHO study, 4.3 million of the world's deaths due to kitchen air pollution in 2012 accounted for 34%, chronic obstructive pulmonary disease and ischemic heart disease were 22% and 26% respectively, and about 6% of the deaths from lung cancer.
There has been a survey in the United Kingdom, in the smoke suction row is not smooth space to do one hours of rice, the lampblack produced by the smoke material, about the equivalent of 2 packs of cigarettes total, it can be said that the kitchen fume has become entangled in the Chinese family healthy life an important issue.
The congested flue
Flue congestion, fume intrusion You might say, isn't there a range hood? Indeed, now the kitchen lampblack machine is standard, but why still appear so many lampblack problem? In fact, the crux of the problem lies in the smoky flue in the building. Modern residential often only a public flue, up and down more than 10 households, and even dozens of families rely on this narrow flue smoke.
Take the 15-21-storey high-rise building as an example, the construction standard stipulates that the flow section of the flue is only 12.8 square centimeters, in a limited space, to concentrate on solving dozens of families of smoke problem, obviously powerless. According to the National Residential Building code, residential ventilation or exhaust duct is not allowed to use brick, must use finished flue. And the kitchen finished flue's outer section size and the number of layers, the higher the number of layers, the larger the size.
According to the relevant provisions of the following specifications:
Below 6 floor: 320X240
Below 12 floor: 340x300
Below 18 floor: 430x300
Below 24 floor: 460x400
Below 30 Floor: 600x400
Below 36 floor: 600x500 It can be clearly seen that although the size of the air duct has been increased in design, but compared to the length of the wind tunnel and the wind drag, such a design for the smoke effect will not play a decisive influence.
It's like a late-night car that's going to jam on a narrow road, when the same building has 1/2 of the kitchen began to produce fumes, the flue may lead to serious congestion, resulting in the oil fume can not be ruled out in time, and even because of the hood pressure is far less than the pressure of the flue gas-induced oil fume intrusion problem.
Because the smoke emission capacity of public flue is generally constant, in the circumstances can not be changed outside conditions, only rely on their own kitchen to solve the problem of poor smoke, the only thing people can do is to improve the performance of the hood.
