The dust holding capacity of the dust filter sleeve, also known as the dust load, refers to the amount of dust accumulated on the filter material per unit area when the given resistance value is reached. The dust holding capacity of the dust collection bag affects the resistance of the filter material and the length of the cleaning cycle. In order to avoid the frequent cleaning of dust removal equipment and prolong the life of the filter bag, it is generally required that the dust holding capacity of the dust removal bag should be larger. The dust holding capacity of the dust filter bag is related to the porosity and air permeability of the filter material. The dust holding capacity of the felt filter material is larger than that of the fabric filter material. Dust collector bag filter efficiency. On the one hand, the filtration efficiency of the filter material is related to the structure of the filter material, and on the other hand, it also depends on the dust layer formed on the filter material. From the perspective of the filter material structure, the filtering effect of short fibers is higher than that of long fibers. Felt media is higher than fabric media. From the point of view of the formation of the dust layer, for the thin filter material, after cleaning, the dust layer is destroyed and the efficiency is greatly reduced, while for the thick filter material, a part of the dust can be retained in the filter material after cleaning, so as to avoid excessive cleaning. Generally speaking, the highest efficiency can be achieved when the filter material does not rupture. Therefore, as long as the design parameters are properly selected, the dust removal effect of the bag filter should be no problem.

The nature of dusty gas has a great influence on the dedusting effect, so we should pay attention to the following points when choosing filter bags: Temperature The temperature of dusty gas is an important factor in the selection of filter bags. Usually, dusty gas < 130℃ is called normal temperature gas, and the dusty gas > 130℃ is called high temperature gas. Therefore, the filter bags can be divided into 2 types: normal temperature filter bags below 130℃ and high temperature filter bags higher than 130℃. In daily work, a suitable filter bag should be selected according to the flue gas temperature. Humidity The dusty gas is divided into 3 types according to the relative humidity: dry gas (humidity < 30%), general gas (30% < humidity < 80%), and high humidity gas (humidity > 80%). (1) When the gas humidity is high, the dust collected on the surface of the filter bag will be wetted and bonded. Filter bags with smooth surface, long fiber and easy dust removal, such as nylon and glass fiber, should be selected. (2) High temperature and humidity will affect the filter bags’ temperature resistance. Try to avoid filter bags with poor hydrolytic stability, such as nylon, polyester, imide and so on. (3) When the humidity is high, circular filter bags should be used to avoid complex and compact filter bags, such as flat filter bags and diamond filter bags. (4) The dusty gas inlet temperature should be higher than the dew point 10-30 ℃. Chemistry In all kinds of furnace flue gas and chemical waste gas, it often contains a variety of chemical components, such as acid, alkali, oxidant, organic solvent and so on, and is often affected by temperature, humidity and other factors. Therefore, when choosing the filter bag, we must grasp the main factors and comprehensively consider the chemical composition of the dusty gas. Finally, when choosing filter bags, we should also consider the dust properties and the dust cleaning method, and comprehensively consider the measurement to ensure that the appropriate filter bag is selected to ensure the dust removal effect.

Due to the variety of materials and specifications of filter bags in real life.  Therefore, when choosing filter bags, we should also choose according to the nature and actual needs of different filter medias. Polyester Fiber Polyester filter media are usually used in low temperature situations, and membrane mulching is usually not needed. Only when the discharge requirement < 30 mg/Nm ³, or when the dust is very fine and the humidity is high. Teflon Polytetrafluoroethylene (PTFE), also known as Teflon, is stretched to become a strong multi-porous material with a pore size of 0.1μm ~ 2.0μm, a porosity > 80%, excellent chemical corrosion resistance, cold and heat resistance, long-term use at-200℃ ~ 250℃, good electrical insulation and smooth surface properties. Polytetrafluoroethylene filter materials are often treated with film mulching or acupuncture to improve dust removal efficiency and prolong filter bag service life. Nomex Nomex filter media can be used for filter bag in the case of higher temperature and thicker dust particles. Nomex has good resistance to high temperature and is more resistant to bending than fiberglass. It can use higher injection pressure and can inject more filter bags with the same pulse valve. Glass Fiber Glass Fiber has good high temperature resistance, tensile resistance, acid-alkali resistance and hydrophobicity, but the glass fiber filter material is not resistant to bending, easy to be damaged in installation and operation, can not be cleaned under high pressure, and has high requirements for filter bag skeleton. After secondary treatment and film coating, the filtration performance of glass fiber is very excellent, and it has been widely used as filter bag material in Europe and the United States. P84 The high temperature resistance of P84 filter bag is slightly lower than that of glass fiber, the acid and alkali resistance is good, and the price is more expensive. Because of its special fiber structure, it is usually unable to cover the membrane, so the filtration efficiency is not as good as that of the coated filter bag.

Filter bag selection is usually carried out according to the nature of dusty gas, the property of the dust and the dust cleaning method of the dust collector. The following principles should be followed when choosing: 1. reasonable structure and high capture rate; 2. good exfoliation, easy to clear dust and not easy to scale; 3. suitable air permeability, low resistance and high filtration precision; 4. high strength and stable dimension; 5. high temperature resistance, chemical corrosion resistance, oxidation resistance, hydrolysis resistance and wide adaptability; 6. a wide range of raw material sources, stable and reliable performance; 7. low price and long life.

Under the increasingly stringent emission standards, systems without denitration treatment or with only SNCR denitration treatment are facing the problem of excessive NOx emission, and it is necessary to carry out ultra-low emission transformation. However, the equipment cost, site cost, and operation and maintenance cost increased by ultra-low emission transformation make most owners distressed. Under this background, Yuanchen Technology's integrated filter material for fluorine green dust removal and denitrification came into being. Yuanchen Technology's fluorine green-dust removal and denitration integrated filter material is based on the dust removal filter material, which is grown, filled, and added with SCR denitration catalyst, so that it not only has the function of filtering dust particles, but also has denitration catalytic function, that is, at the same time. It has the function of removing particulate matter and NOx. Xiao Fluorine Green Dust Removal and Denitrification Integrated filter media integrates fiber modification, filter media processing, filter media post-treatment, catalyst preparation, in-situ growth, gel loading and other methods, and successfully realizes the SCR denitration catalyst on filter media fibers. In situ loading and interstitial filling between fiber pores. The activity of fluorine green ∙ dust removal and denitrification integrated filter material can reach more than 90% at 180~200 ℃. Due to its excellent denitration activity, the integrated filter material of fluorine green and dust removal and denitration can not only be applied to the dust collector at the back end of the SNCR process, but also can replace the SCR denitration catalyst of other processes. The integrated filter bag for dust removal and denitrification can be designed into a variety of structures such as single-layer, double-layer, single-layer film, and double-layer membrane.

With the increasingly severe environmental situation, my country, as a major emitter of air pollutants, has paid more and more attention to the emission of multi-pollutants in the flue gas of coal-fired power plants. Under the guidance of the green sustainable development concept, the concept of collaborative governance has been proposed and implemented in used in coal-fired power plants. The synergistic treatment technology of flue gas pollutants mainly includes the synergy of coal control and pollutant removal, the synergy of low-nitrogen combustion and flue gas denitrification, the synergy of dust collector and wet desulfurization tower, and the integration of boiler flue gas system. First of all, the synergistic technology of coal control and pollutant removal. The key of this technology is to compare the cost of environmental protection equipment construction and equipment operation when using inferior coal and the increased cost of coal quality control, and then determine the coal quality. The appropriate range of fluctuations to determine the use of this synergistic technology. Secondly, the synergistic technology of low-nitrogen combustion and flue gas denitrification, the key of this technology is low-nitrogen combustion technology, which can control the production of nitrogen oxides from the source, and then comprehensively consider the construction and operation costs of flue gas denitrification technology, combining the two technologies The cost comparison of this collaborative technology is optimized. Third, the synergistic technology of dust collector and wet desulfurization tower, the main function of this technology is to improve the dust removal efficiency, and then use wet electrostatic precipitator or low temperature flue gas system technology to meet different emission requirements. Fourth, the integrated technology of boiler flue gas system, the focus of this technology is to optimize the design of the tail flue as a whole to improve the treatment efficiency of the entire boiler flue gas. Nitrogen oxide treatment measures: First, in anthracite coal boilers, low-nitrogen combustion technology and blending technology can be used to effectively control the mass concentration of nitrogen oxides at the furnace outlet, which can generally be controlled to about 800mg/m3, and then use furnace type SNCR. Flue gas denitrification technology is used to control the mass concentration of nitrogen oxides within 500mg/m3, and finally, the mass concentration of nitrogen oxides is controlled within 50mg/m3 through SCR flue gas denitration technology. Secondly, in lignite, bituminous or lean coal boilers, low-nitrogen combustion technology and SCR flue gas denitration technology can be used comprehensively. When low-nitrogen combustion technology is used, it can effectively control lignite, bituminous coal, and lean coal boiler furnace exit flue gas nitrogen oxides The mass concentration should be within 200mg/m3, 300mg/m3 and 500mg/m3 respec...