In the process of cement production, a large amount of dust with high temperature, high humidity and corrosive gas is generated, and the dust concentration is high, and the temperature fluctuation range is wide. Only the glass fiber filter material with high temperature resistance, corrosion resistance and dew resistance can meet the needs of dust removal in the cement industry.
In the process of cement production, the chemical composition, physical properties and working conditions of flue gas dust at different dust raising points are different; Secondly, different types of bag filters are used, and their filtering methods, dust removal methods and filtering wind speeds are far different. After decades of research and development, the types of glass fiber filter materials continue to increase, and are more specific and targeted. Only by selecting appropriate filter materials according to the working conditions of the actual point of use can they meet the needs and play their due role.
Glass fiber can be divided into two categories in terms of alkali metal oxide content in its glass composition, alkali free glass fiber and medium alkali glass fiber. The different content of alkali metal oxide affects the production process of glass fiber and determines the performance of glass fiber and its products. Alkali free glass fiber can produce single fiber diameter of 8~9 μ Fiber. With different fiber diameters, the strength, wear resistance, folding resistance and other properties of woven glass fiber cloth with the same thickness vary greatly.
The difference of glass fiber material will affect its use temperature. Alkali free glass fiber filter material can be used for a long time at 280 ℃, and the instantaneous temperature resistance (within 1 hour) can reach 350 ℃, while the use temperature of medium alkali glass fiber filter material is only 260 ℃, and the instantaneous temperature resistance is below 300 ℃.
The permeability and filtration efficiency of glass fiber filter materials are closely related to their fabric structures, which are divided into three categories: twill, satin and weft.
In the dusty flue gas, with the same fabric structure, the permeability of glass fiber expanded yarn filter material is higher than that of continuous glass fiber filter material, and the permeability of glass fiber needle felt material is the highest.
The thickness of glass fiber filter material (sometimes measured by the mass per unit area) will determine the breaking strength of this filter material and the filtering wind speed used, as well as the radial breaking strength of alkali free continuous glass fiber filter material and alkali free glass fiber bulk yarn filter material.
All kinds of glass fiber cloth or mat can only become glass fiber filter materials after surface treatment, and can be suitable for use under different working conditions to achieve the purpose of smoke suppression and dust removal.
Glass fiber bulk yarn filter bag has good dedusting effect
The temperature, humidity, dust concentration, chemical composition and particle size distribution of the dust, and the composition and content of harmful gases in the flue gas produced by different dust raising points are not only the same. As far as the cement industry is concerned, the characteristics of flue gas and dust at the dust raising points such as rotary kiln, mechanized vertical kiln, dryer, coal mill, clinker mill, raw meal mill and grate cooler are different. Different regions and manufacturers adopt different production processes, raw material ratios, and types of coal burned, and the characteristics of flue gas and dust produced are also different. After decades of research and development, glass fiber research and design institute with special surface treatment agent shall be selected to develop a surface treatment formula suitable for smoke suppression and dust removal of dust points in the cement industry.