The first step of the design and selection of the pulse bag filter
is to learn the condition of the dusty gas that need to be processed (including treating capacity, temperature, humidity, dust content, dust property, etc.), and then design and select pulse bag filters. The pipe system and auxiliary equipment are the same as other dust collection systems. SENOTAY pulse bag filters will be your best choice. When designing and selecting pulse bag filters, you should consider these problems.
1. If pressure loss is lacking in more appropriate design experience, 75 x 9.8 PA can be used as a typical data at low filtration speed. However, if it adopts higher filtration rate, or there is a sticky or low porosity dust layer, a higher value should be used.
2. Filter speed is the ratio of air to cloth. It is the ratio of filtered gas flow (m3/min) to the dust bag area (M2), and its dimension is m3/min.m2=m/min. This is the unit of speed, which represents the average velocity of gas passing through the dust collector filter bag, regardless of the area occupied by the fiber of fabric. For this reason, it is often called "apparent surface velocity".
Filtration rate is a very important factor that determines the performance of dust collector filter bag. If filtration rate is too high, it will cause too much pressure loss, reduce the efficiency of dust removal, and make the dust collector filter bag clogged and premature damaged. However, increasing filtration rate can reduce the filter area required by dust collector filter bag, so that the same volume of gas can be treated by smaller dust collection systems.
There is an optimum filtration rate for a set of design parameters (i.e. type of dust collection systems, dust cleaning mechanism, fabric material and fabric structure of dust collector filter bags, dust properties and etc.). Generally, the filtration rate of fine dust is lower than that of coarse dust, and the filtering speed of smaller dust collection system is higher than that of larger ones. Pulse jet type filters and reverse jet type filters can achieve higher filtering speed than vibration and reverse airflow type filters.
As to vibrating type and reverse airflow type filters, it can adopt the filtration speed of 0.9m/min for ordinary dust,. From the point of view of both investment and maintenance, it is recommended that the maximum filtration rates of feed, grain dust and flour should be 0.98 and 0.75 m/min respectively.
3. The actual fabric area (m2) can be obtained by dividing the flow rate (m3/min) of gas flowing into the dust collection system by the selected filtration rate (m/min). Due to temperature changes and additional increases or decreases of air, the volume of the dusty gas entering the dust collection system is not necessarily the same as the volume of the gas discharged during the production process. If the dust collection system is used in the condition of variable flow rate, it is necessary to make a judgment whether the filter area is calculated according to the peak flow rate or the average flow rate. In addition, we should also consider the storage quantity of the fabric of dust collector filter bags, so as to carry out dust cleaning, inspection and maintenance.
4. Shell structure, the number of compartments needed by a bag filter system is relatively easy to determine. After determining the area of dust collector filter bags in each compartment, it is necessary to determine the most favorable length, diameter and arrangement spacing of the dust collector filter bag. The general length of the dust collector filter bag should be no less than 50 mm spacing; the filter bag spacing of extra long (such as more than 3 meters) dust collector bags should be larger. Dust collector filter bags should be grouped, and you should leave a channel between the two groups. If there is only one channel on one side and the diameter of the dust collector filter bag is 150 mm, each group should not have more than three or four rows of dust collector filter bags; each group of 300 mm diameter should not be more than two rows. If there are channels on both sides, filter bags of diameter 150 millimeters should not be more than eight rows, and filter bags of diameter 300 millimeters should not be more than four rows. The width of the channel is 450~600 millimeters. The total number of filter bags in each group depends on the vibration mechanism. Usually, a group of filter bags are equipped with a set of vibration mechanism. A compartment can contain several groups of filter bags.