Bag filter is to remove dust from the dust in the efficient dust removal equipment. The dust removal mechanism is mainly used to filter dust on the surface of the filter dust filter. Highly characterized by high dust removal efficiency, dust exhaust through the bag filter, the concentration of the discharge can generally be stable to 50mg / m ³ below, or even up to 5mg / m ³. In the increasingly demanding environmental protection today, bag filter with other dust removal method is difficult to match the advantages.
Bag filter is generally by the host, filter components (dust bag) and back blowing control and other auxiliary systems. The dust bag is the core component of bag filter. Its material, sewing, use and maintenance are related to the efficient and stable operation of the whole system. The dust volume, dust concentration, load balance, flue gas temperature and humidity, corrosivity And other factors may cause dust bag damage failure. Among the various types of dust bag breakage failure, wear is a common type and is closely related to the design, manufacture and application of dust collectors.
The category and cause of failure of dust bag breakage
Common dust bag damage failure mainly wear, burning and corrosion.
Dust bag wear refers to the use of dust bag during the process, due to repeated filtering and backflush state switch, bag bulging and contraction, bag and dust skeleton or other components to produce relative movement between the high-speed dust flow erosion caused by local wear.
Dust bag is burned due to abnormal heat treatment of high temperature, or high temperature dust particles, the temperature is higher than the temperature of the filter, so that the high temperature parts of the filter damage caused by damage.
Filter bag corrosion is due to the harmful ingredients in the flue gas caused by the chemical reaction, resulting in decreased mechanical properties of the filter and damage failure. Filter bag corrosion occurs in the flue gas composition of excessive conditions, can be divided into gas corrosion and liquid corrosion, harmful gas components in the presence of liquid, the more likely to cause damage to the filter bag.
Due to the presence of liquid components in the flue gas (such as condensation), and dust to form a paste material, plug the filter bag gap, resulting in dust bag lead to dust failure.
Prevention and treatment of dust bag wear
Dust bag wear is the main type of bag damage failure, other types of damage caused by damaged small holes, the dust flow of the erosion also produce further wear. Wear and bag filter structure design, air flow organization, backflush cleaning, etc. are closely related. Dust filter bag wear parts are divided into the following five cases: filter bag pocket, filter bag bag, filter bag lower, filter bag bottom and filter bag inside, different parts of the wear and tear of the situation and its different, Also different.
Dust bag bag pocket parts of the wear and tear:
Bags pocket parts of the wear and tear more than 400mm down in the pocket, broken traces are mostly from the inside out. This type of wear is mainly due to the initial pulse of the compressed air from the bag center, direct erosion of the bag wall caused by the wall. In the deviation from the side of the compressed air constantly washed, the filter bag inside the first layer of compressed air blowing off, and then the fabric was blown, the last filter surface was blown. When the bag side of the bag after the break, the damage at the break down, dusty smoke will quickly enter from the break, scouring at the diagonal, forming a new hole and the new dust flue gas inlet, increasing the hole eventually caused the bag Mouth ring broken, serious even when the bag head and bag body separation. This type of damage is mainly caused by excessive pressure of compressed air, jetting short tube skew, deformation of the flower plate and other reasons, once found such wear, put on a new bag before the blow blow to check or repair.
Filter bag body wear:
Dust bag bag body wear, common filter bag vertical strip wear traces, divided into several cases:
If the damage marks from the inside out, broken in the bag cage vertical bar contact, that is the cage cage vertical bar welding or corrosion, the filter bag wear or injection pressure is too high, too frequent blowing, so that the bag and bag cage The contact position is broken due to breakage. This type of wear can be solved by replacing the bag cage or adjusting the blowing device.
If the traces of damage from outside to inside, broken in the bag cage vertical bar contact. Often visible outside the filter bag (adjacent filter bag or box components) with the filter bag wear marks. This type of wear is the bag cage deformation or filter bag installation is too small, filter bag diameter is too large or loose, causing the filter bag and filter bag, filter bag and dust collector box between the contact, in the process of blowing The friction is rubbed agai