[China Aluminum Network] Zeolite is a type of alumino-silicate mineral containing water-like structures. It was discovered earlier in 1756. Cronstedt, a mineralist in Sweden, discovered that a natural aluminosilicate ore produced boiling on ignition and was therefore named “zeolite†(Szeolit ​​in Swedish). In Greek it means "lithos" (zeo) of lithos. Since then, people have been deepening their research on zeolites. Zeolite has the properties of adsorption, ion exchange, catalysis, and acid and heat resistance. Therefore, it has been widely used as an adsorbent, ion exchanger and catalyst, as well as for gas drying, purification and sewage treatment.
It is unavoidable to generate "three wastes" during the spraying process, in which the spray exhaust gas is the main part of the "three wastes." Spraying exhaust gas from the diluent volatilization, organic solvents will not be attached to the paint surface with the paint, will be released in the paint and curing process, the formation of volatile organic compounds (VOCs), the main components of benzene, toluene and xylene benzene system And other non-methane hydrocarbons and other substances, these substances are of great harm, known as the "invisible killer." Especially in the case of spraying without protection, the concentration of benzene in the air in the workplace is quite high, and the physical harm to the workers is also very large, ranging from aplastic anemia to leukemia. Direct discharge into the atmosphere can cause pollution problems such as acid rain, smog, and photochemical smog, and endanger human health and ecological environment safety.
The spray exhaust gas mainly comes from the spraying and drying process. The source of the spray is the paint booth, drying chamber and drying chamber.
At present, the state has issued a policy on the levy of VOCs for the control of VOC emissions. Regardless of whether the company discharges emissions or not, the sewage charges should not be escaped. Industry can't stop, so VOCs must be generated. A more direct and effective way is to effectively trap and release released VOCs.
Then the problem came. The concentration of VOCs in exhaust air from paint spray booths and drying rooms was very low, but the amount of air flow was particularly large. The main components of pollutants were aromatic hydrocarbons, alcohol ethers, and ester organics. What are the methods of VOCs produced in this place that can be effectively managed?
At present, the more mature methods abroad are: firstly concentrate low-concentration high-air volume gas into high-concentration and small-air volume gas; use adsorption method to adsorb low-concentration ambient temperature paint exhaust gas; use high-temperature gas to desorption; and concentrate the gas using RTO and RCO. The process is processed. In the whole process, the concentration device is very important. According to the composition and working conditions of the exhaust gas, the concentration device can select activated carbon adsorption and zeolite wheel adsorption.
There are many zeolite wheels on the market. How do you choose the zeolite wheel?
1. Select high zeolite content
Since the zeolite content directly determines the adsorption efficiency, the content of zeolite is crucial.
2. Choose a good hydrophobicity
The adsorption performance of zeolite is good or bad, not only depends on whether its specific surface area is large enough, but also whether the hydrophobicity is excellent, especially in the environment where the exhaust gas humidity is more than 60%, it is the hydrophobicity of the tested zeolite, and the zeolite with poor hydrophobicity is easy to be Plugging pores reduces adsorption efficiency. Therefore, in order to ensure the adsorption performance, the specific surface area and hydrophobicity are indispensable.
3. Select high desorption efficiency
The purification efficiency of zeolites is not high, and it is not only the absorption, but also the desorption function. If the desorption function cannot be achieved nearly completely, the adsorption efficiency of the zeolite will be affected for a long time, and the service life of the zeolite will be directly affected. The zeolite is resistant to high temperatures and the desorption temperature is high, and no reaction heat occurs.
Everyone saw it, did it feel very harsh?
In fact, the following conditions can be met, and these problems can be solved.
honeycomb
The zeolite structure is designed as a honeycomb, which is beneficial to the adsorption of zeolite on VOCs components, and is suitable for low concentration and large air volume.
Applicable VOCs: benzene, toluene, xylene, styrene, hexane, cyclohexane, MEK, MIBK, acetone, ethyl acetate, NMP, THF, methanol, ethanol, propanol-1C, butanol, and various Chlorine system solvent etc.]
Adsorption and concentration principle
When exhaust gas containing low-concentration VOCs passes through the honeycomb zeolite, the VOCs components are adsorbed in the zeolite, and the purified gas is discharged into the atmosphere or discharged into a room for circulation processing, and heat energy is recovered through the recycling process. At this time, the VOCs-adsorbed honeycomb zeolite continuously rotates, and adsorption regeneration is performed in the desorption module using a small amount of heated air. During this process, highly concentrated gas can be obtained from the low-concentration exhaust gas.
Zeolite requirements
Using natural zeolite (sodium aluminosilicate), combined with practical application requirements, the zeolite is designed and processed into drum type and tray type. The user can select different types of zeolite according to the characteristics, composition and air volume of VOCs in the exhaust gas.
The zeolite content must be high, so that the adsorption and concentration performance of the zeolite can be more excellent, especially the aromatic organics, the adsorption capacity is stronger, and there is a clear advantage in dealing with exhaust gas with higher relative humidity, and there will be no sharp increase in the amount of water absorption. Happening.
In addition to technical requirements, service providers are required to have sufficient experience in VOCs management. In the face of exhaust gases containing any components, they can make precise and perfect solutions to ensure the program's enforceability and discharge standards.
Hardware: Traditional Hardware Products, also called "small hardware". Refers to five metals: gold, silver, copper, iron, and tin. Can be made into art objects or metal devices such as knives and swords after manual processing. Hardware in modern society is more extensive, such as Hardware Tools, Hardware Parts, daily hardware, construction hardware and security supplies. Most hardware products are not final consumer goods.
History entered the modern industrial society, and the metal-hardware industry has developed rapidly. The hardware industry has played an inestimable role in the development of the national economy. Hardware products have also become an indispensable industrial link in industrial manufacturing.
Instead, it is used as supporting products for industrial manufacturing, semi-finished products, and tools used in the production process. Only a small number of daily hardware products are necessary consumer goods for people's daily life.
In the National Economy Industry Classification of the National Bureau of Statistics, manufacturing is the third largest industry. These include: production and production of living materials, such as: agricultural and sideline products, food and beverage, tobacco, textiles, clothing, leather, wood furniture, printing and sports supplies, and pharmaceutical manufacturing; manufacturing of production materials, such as petrochemicals, chemical fibers, rubber and plastic , Non-metal product manufacturing, metal smelting and processing, metal product manufacturing, general equipment manufacturing, industry-specific equipment manufacturing, and transportation equipment manufacturing, electrical equipment, communications electronics, and so on.
The related products in the category of metal products in manufacturing and general parts and components in general equipment manufacturing constitute the "small hardware" in the usual sense. It can be seen that 'small hardware' is not an existing industry category, but a cross combination of the above-mentioned several metal products-hardware products. In the entire manufacturing industry, the responsibility of 'small hardware' is to provide manufacturing enterprises with parts and production tools, not as industry-specific equipment for final use. Nevertheless, we cannot deny the important role of "small hardware" in the social production process: "small hardware" and manufacturing are an inseparable whole that is intertwined.
Hardware Products
Furniture Hardware,Door Hardware,Hardware Tools,Architectural Hardware
Jieyang Xinxin Industry and Trade Co., Ltd. , https://www.gdxxgm.com