Corrosion is one of the common reasons for the damage of the filter cloth. Because the smoke contains a variety of corrosive substances, and the corrosion effect is large in the high temperature environment, the filter cloth will be damaged. The main causes of corrosion are hydrolysis, oxidation, acid and alkali corrosion. The main causes of damage are hydrolysis and oxidation, and acid corrosion is less, alkali corrosion is less.

The main reason for the corrosion of the filter cloth is that the flue gas contains acid and alkaline components, which change with the concentration of these chemical substances. If the dust collector is turned on or shut down, the SO2 in the exhaust gas meets water to form H2SO4, which will cause the fiber of the filter bag to harden, deform and lose strength and be damaged.

Most traces of corrosion damage are radial and form a large area of discoloration on the surface of the filter bag, resulting in the bag becoming hard and brittle and a small number of irregular circular holes. However, different from the irregular circular holes caused by the burning of Mars through the filter bag, they can be distinguished by the naked eye.

The bottom of the filter cloth is damaged

Frayed bottoms of press cloth are more common, possibly because the bottom of the cage is too small or the press cloth is too long and the cage only supports the bottom of the bag. When excessive movement causes the inside of the press cloth to wear, the press cloth is cleaned and filtered. Or excessive dust accumulation to form eddy wear filter cloth.

Chemical corrosion filter cloth:

Chemical etching is the most obvious manifestation of the strength in acid etching, alkaline etching, oxidation and corrosion discarding dust collection bags, especially as a result of the corrosion loss of the hydrolysis of the filter cloth, can withstand the load, thus losing filtration performance. This phenomenon is mainly due to problems with the selection of press cloth performance and failure losses due to conditions with cloth or use environment beyond the range of said fibers.

Filter cloth acid corrosion

High temperature filter materials generally have acid corrosion, mainly sulfur oxide. Especially in flue gas desulphurization of coal-fired boilers, high sulfur coal is used, and the sulfur oxide content in flue gas is high, reaching 5000 mg/nM3. Sulfite and sulphuric acid form from sulfur oxides at high temperatures, causing corrosion and failure of the filter material. If the flue gas contains HF, it can not use glass fiber filter material, which is easy to be corroded by acid, resulting in the failure of filter material.

The operating temperature of flue gas is generally above the acid dew point. If the temperature is below the dew point, the filter system must be turned off to avoid corrosion of the filter cloth. Acid liquid has hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid and so on.

Filter cloth alkali corrosion

Most of them appear in the process of sodium salt and ammonia chemical production, such as sodium chloride, ammonia water, sodium carbonate and other working conditions. Power plants, cement plants, waste incineration plants, steel plants and other flue gas dust removal field less.

Filter cloth oxidation corrosion

Oxidative corrosion damage refers to a certain amount of oxidizing agent, because oxidative corrosion is mainly used in the filter medium based on PPS, will lead to the oxide-based filter material PPS nitrogen oxide, oxygen, ozone destruction, concentrated sulfuric acid.

Changzhou Xiahua Environmental Protection Technology Co., Ltd. specializes in the production and operation of industrial filtration materials for many years, mainly in the chemical industry, and the products are exported to many countries. Xiahua mainly produces the filter cloth, filter bag, pressure filter bag, etc., Xiahua filter cloth, use heart!