Bag filter manufacturer in Tehran

A bag filter is a container containing a number of polyester bags that, when the gas containing dust passes through the inlet valve and moves towards the filter outlet, the dust on the outer surface of the bags settles. . Then, at certain times, by applying the air pulse, the dust on the bag is shaken and poured into the hopper below the filter. In this way, the dust is separated from the gas. Another equipment that is widely used for dedusting the air in the cement industry is bag filters. These types of filters have high dust removal efficiency, which can be up to 99.9% efficient according to the type of dust. The factor that limits its use is the temperature of the gas entering it, with new developments in the preparation of bag fibers, the scope of their use has become wider. With the use of new textile artifacts, the bags can withstand temperatures above 200 degrees. They have centigrade. The following factors play an essential role in bug filters:

The gas carrying the dust enters the filter and is returned by the baffle to the exit funnels. The dusty gas enters one of the filter houses and the dust particles with a larger diameter move towards the hopper under the influence of their own weight and the rest are collected on the filter bags. When the thickness of the accumulated dust on the bags reaches such a level that the flow is difficult to pass, the cleaning stage of the bags begins. and causes uniform distribution of the gas carrying fine dust particles between the bags. The gas distribution makes the gas flow on the bags not cause excessive wear.

The dust-carrying gas goes to the bags and from there enters the cleaning air chamber and then is sent to the chimney by the suction fan. At the same time as the above operation is done continuously, the pulsed air is periodically blown into the bags through the pulse valves and nozzles by the programmed electric panel and causes the materials to be separated from the outer surface of the bags. The separated material enters the Harper and from there it is directed to the outside of the filter by transfer systems.

Each row of filter bags is cleaned using compressed air through a separate pipe and nozzle installed in the upper part of the bags. For this purpose, compressed air tanks are cleaned. For this purpose, compressed air tanks with complementary diaphragm valves are placed at the end of each nozzle. These diaphragm valves are opened and closed by solenoid valves that operate periodically by the electronic controller. The compressed air that comes out of the compressed air tank is blown into the bag through the nozzle blowing tubes and the injector tube jet that is installed exactly above the bags. Due to the injector property, some of the air in the clean chamber is also sucked into the bags. Using this method, even six-meter-long bags can be cleaned.

The compressed air pulse that cleans the bags is better compared to the positive and negative electrode impact hammers in the electrodes according to the size of the equipment. related, such as engine gearboxes, hangers, positive and negative anvils, do not wear out and do not require tiresome mechanical repairs and adjustments. An important issue that should be considered from the combustion and firing of the cleaner is the amount of filter bags against high temperature gases. With the changes in cleaner production technology, the use of filter bags has undergone changes, the latest of which is lowering the temperature of exhaust gases to a temperature of less than 200 degrees Celsius. The use of bag filters dedusts gases up to 10 milligrams per cubic meter.

An important factor that should be considered when determining the dust removal area is determining the appropriate speed of the dust removal operation, which should be considered. Bag filters are divided according to the type of cleaning method. Cleaning of bags is done in two ways, online and offline. In online mode, the intended container is not removed from the production line and is still in the gas path, but in offline mode, the container is separated and isolated from the production line, and after the cleaning operation is completed It opens to the line. Cleaning the bags is possible in three ways: the reverse air method, the air jet method, and the mechanical method.

In the past, you generally used Mechanical Shaking and sometimes Reverse air. But currently, Pulse jet cleaning method is used. Cylindrical metal shelves called cage are used in pulse jet type bag filters to prevent bags from gathering inside them. The cage and the bag are hung vertically from a perforated plate called a tube sheet. To separate the layer of soil settled on the outer surfaces of the bags, a pulse of compressed air with high pressure is used, which enters the open opening of the bags from above. In other words, the dust that covered the filter bags falls into the hoppers by means of quick and short air pulses. Dust enters the transmission system to the production line through the hoppers below the filter.

Hybrid filter is one of the types of dust collection systems that integrates electrofilter and bag filter technology together. The resulting system is durable and economical and has a high dust extraction power. The design of this type of filters using the two mentioned technologies at the same time has made it possible to design with a higher ratio of air to the filtration level in the bag part. This reduces the surface of the fabric and thus the number of bags, the number of gauges, the valves related to the impactor system in the bag part. Reducing the number of these parts ensures greater efficiency and durability of the device and lower maintenance costs. Although electrofilters have mechanical strength and high resistance to temperature, but when the output rate is less than 10mg/m3, it becomes very expensive and expensive.

Electrofilters compared to bag filters in different gas volumes. They have less pressure drop. Also, the bag filter can separate more dust than the electrofilter and work independently of the gas and dust conditions, but they are sensitive to temperature. If increasing the efficiency of the filter by increasing the efficiency of the cement production line is considered, the electrofilter becomes very expensive and costly. Converting an electrofilter to a bag filter requires a new fan that is more powerful than the previous fan of the electrofilter. Therefore, to increase the efficiency of dust collector systems and use the advantages of electrofilters and bag filters at the same time, the idea of ​​combining the above two systems led to the production of a compound or hybrid filter in the family of dust collectors. The interaction of two electrofilter and bag filter systems in a single system has increased the efficiency of the system in absorbing fine dust particles and forming an integrated, stable and economical system.