Introduction to Bags
Fiberglass cloth is the traditional main filter material in bag filter, which uses a weaving process to pass glass fiber through, warping, weaving, dyeing and other processes are woven into fiberglass fabrics woven into different textures (often divided into plain, twill, satin). The filter material has stable dimensional, high temperature resistance, large void ratio, good gas permeability and wide application. Because of its low price and high temperature resistance, fiberglass cloth is the most cost-effective filter medium at high temperatures.
The fiberglass cloth is often impregnated with silicone oil, graphite, film, and PTFE according to the characteristics of dust from different manufacturers. After processing, the fiberglass cloth with different treatments has increased permeability, easy cleaning (fast dust removal), water and oil resistance (anti-condensation), antistatic, high dust collection rate and resistance. Corrosion and other properties, forming a series of products.
The working principle of the bag filter is to rely on a woven or felted (pressure) filter cloth as the filter material. When the dusty gas passes through the filter bag, the dust is retained in the filter. On the surface of the bag, the dry air is discharged through the gap between the fibers of the filter bag, thereby achieving the purpose of separating the dust of the dust-containing gas. Its working mechanism is that the dust is trapped by the effects of screening, inertia, adhesion, diffusion and static electricity generated by the filter cloth.
The advantages of the dust bag:
1). The dust removal efficiency is high, and dust of 0.3 nm or more can be collected to purify the dust-containing gas to 15 mg/m3 or less.
2). It can capture dust that is difficult to recover by electric dust removal; and it can collect compounds such as nitrates and sulfides to a certain extent.
3). It has good adaptability to load changes, and is especially suitable for collecting fine and dry dust. The collected dry dust is easy to handle and recycle.
4). Bag filters are safer when collecting dusty gases that contain explosion hazards or sparks.
Classification of bag filters
The large body structure of the bag filter is various and can be used according to the cross-sectional shape of the filter bag and dusty gas. The direction of the flow filter bag, the arrangement of the air inlet, the gas pressure inside the dust collector, and the cleaning method are classified into five ways. The important parameters such as dust removal efficiency, pressure loss, filtration speed and filter bag life of the bag filter are related to the cleaning method. The common bag filter product structure is mainly classified according to the cleaning method.
The important parameters such as dust removal efficiency, pressure loss, filtration speed and filter bag life are related to the cleaning method. Therefore, the bag filter is mainly classified according to the cleaning method. Three major categories of products: mechanical vibration, pulse blowing, anti-blowing and cleaning.
Main process steps for dust bag 【
1, cleaning: using high frequency vibration, will enter the larger wall of the filter bag The dust particles are removed as much as possible, which does not affect the entanglement fastness of the fibers, and maintains good peeling resistance of the filter bag.
2. Chemical experiment treatment: extract the bag sample, use professional equipment to test the oil content of the filter bag, select the appropriate washing material, and wash the filter bag to the maximum without causing any damage to the filter bag. .
3. Cleaning: Select suitable washing materials and strictly mix, low-temperature water cleaning, uniform water flow, moderate strength, no mechanical damage to the filter bag.
4. Drying: Drying with hot air at around 110 °C, maintaining the dimensional stability of the filter bag, and the filter bag is not deformed after drying, and does not retract.
5. Repair: Repair the damaged filter bag caused by abrasion or hole caused by the use, and ensure a high recycling rate.
6. Detection: The instrument is used to check the physical value of the cleaned filter bag to ensure that the cleaning quality meets the requirements.
How to purchase high-quality dust-removing bags
Purchasing good dust-removing bags In order to meet the needs of production, dust-cleaning bags should meet the following requirements:
1. It has good gas permeability. The function of the bag filter is to remove the dust, so the dust holding capacity of the filter material must be large enough. Now there are some dust-cleaning bags with poor quality on the market. Every time they open the function of cleaning, they will “shrink” once, which is the unqualified product.
2, strong resistance to temperature and corrosion. I believe that most companies know that if the dust bag does not have good temperature and corrosion resistance, it will be destroyed soon, and the performance of dust removal will be lost, which will affect the normal use of the bag filter.
3, easy to clean. The quality of the cleaning dust has a certain relationship with the quality of the dust bag itself. For example, the material of long fiber and short fiber, the material of short fiber, although it has very good dust filter, it is more difficult to clean the dust above.
When testing a new dust bag, you should pay special attention to the following points:
1. Pay attention to the presence of condensation in the bag room. Whether the ash discharge system is unblocked. Prevent clogging and corrosion from occurring, and the accumulation of ash will affect the production of the host.
2. Handling air volume and pressure and temperature at each test point are consistent with the design.
3. If the filter bag is installed, whether it has been dropped, loosened, worn, etc. after use, it can be judged by visual inspection of the chimney discharge after commissioning.
4. Direction of rotation of the fan, speed, bearing vibration and temperature.
5. Adjustment of the cleaning cycle and cleaning time, this work is an important factor in the performance of the dust collection and operation. If the cleaning time is too long, the dust layer will be removed and become a cause of leakage and breakage of the filter bag. If the cleaning time is too short and the dust on the filter bag has not been cleared, the filtration operation will be resumed, and the resistance will be quickly restored and gradually increased, eventually affecting the use effect.
At the same time, we recommend the dust bag of Standard Group. There are many varieties and different types of products. Different industries have different use standards. The most distinctive feature is the nanofiber dust bag, which will be the future industrial development. Environmental needs.