In industrial production, a large amount of dust is often generated, and with the strict implementation of environmental protection laws, industrial producers are required to equip corresponding dust removal equipment. And with so many dust removal equipment, how do they work? Below is a brief introduction to several commonly used industrial dust removal equipment in the market.

 

1 Bag dust collector

 

The working principle of a dust collector is as follows: the dusty gas enters the filter chamber through the lower open flange, and the coarser particles directly fall into the ash bin. The dusty gas is filtered by the filter bag, and the dust is trapped on the bag surface. The clean gas is then transported to the clean gas chamber through the bag mouth and discharged into the atmosphere by a fan. When the dust on the surface of the filter bag continues to increase, the programmable controller begins to work. Pulse valves are opened one by one, allowing compressed air to spray and clean the dust on the filter bag through the nozzle, causing the filter bag to suddenly expand. Under the action of reverse airflow, the dust on the bag surface quickly separates from the filter bag and falls into the ash bin, and the dust is discharged by the ash discharge valve.

 

Application industry: Mainly used for separating particulate dust and fine dust from industrial waste gas, widely used in metallurgy, mining, cement, thermal power plants, building materials, casting, chemical industry, tobacco, asphalt mixer, grain, mechanical processing, and boiler dust removal.

 

2 Cyclone dust collector

 

After adding a bypass, the working principle of a cyclone dust collector is that dusty gas enters tangential from the inlet. While the airflow obtains rotational motion, the airflow separates upwards and downwards to form a double spiral motion. The dust has a strong separation effect at the boundary of the double spiral, and coarser dust particles are distributed to the outer wall with the downward spiral airflow. Part of the dust is led out from the middle opening of the bypass separation room, and the remaining dust is carried into the ash hopper by the downward airflow. The upward spiral airflow has an aggregation effect on fine particle dust, thereby improving the dust removal efficiency. These finer dust particles are carried upwards by the upward spiral airflow, forming a strongly rotating upper dust ring under the top cover. They enter the upper opening of the bypass separation chamber together with the upward spiral airflow, and are introduced into the cone through the return air outlet to converge with the internal airflow. The purified gas is discharged through the exhaust pipe, and the separated dust enters the hopper.

 

Application industry: mainly suitable for the coarse and intermediate purification of dust in various industrial boilers, mechanical processing, metallurgical building materials, casting, mining, cement, and mining.

 

3 Pulse dust collector

 

The dust collector mainly consists of an upper box body, a middle box body, an ash hopper, an air inlet uniform flow pipe, a support filter bag and a spraying device, an ash unloading device, etc. Dust containing gas enters the ash hoppers of each compartment through the air inlet uniform flow pipe of the dust collector. Under the guidance of the ash hopper guide device, large particles of dust are separated and directly fall into the ash hopper, while finer dust evenly enters the middle box and adsorbs on the outer surface of the filter bag. Clean gas enters the upper box through the filter bag and is discharged into the atmosphere through various offline valves and exhaust pipes. As the filtration process progresses, the dust on the filter bag accumulates more and more. When the equipment resistance reaches the limited resistance value (usually set at 1500pa), the ash cleaning control device automatically closes the one room offline valve according to the differential pressure setting value or the ash cleaning time setting value, opens the electric pulse valve according to the set program, stops blowing, and uses compressed air to instantly spray to increase the pressure inside the filter bag. The dust on the filter bag is shaken off (even fine dust can be thoroughly cleaned) and discharged into the ash hopper by the ash discharge mechanism.

 

Application industries: calcium carbide furnaces, various electric furnaces in ferroalloy plants, steel plants, coal-fired boilers and small boilers in power plants, waste incinerators, high-temperature flue gas from smelters, aluminum plant flue gas, cement plants, carbon black plants, etc. Its application field is characterized by high temperature and large smoke volume.

 

4 Electrostatic precipitator

 

After the dusty gas enters the equipment from the top air inlet, it passes through the cyclone separator at high speed, causing the dusty gas to rotate downward along the axis adjustment spiral. By using centrifugal force, the coarse dust particles are removed, effectively controlling the initial dust concentration entering the electric field. Then, the gas enters the electric field through the lower ash hopper for operation. Due to the cross-sectional area of the lower ash hopper being several times larger than the cross-sectional area of the inner tube, according to the principle of constant rotation moment, the radial and axial wind speeds sharply decrease to create a zero velocity interface, causing heavy particle dust in the inner tube to settle in the lower ash hopper, reducing the dust concentration entering the electric field. Low concentration dust containing gas is collected by electric dust collection and condensed on the anode and cathode plates, and the collected dust is transported away by the lock air ash discharge device through ash cleaning and vibration. In order to prevent secondary dust formation in the lower ash hopper after the inner tube cyclone and electric field electrode plate vibration, an isolation cone is specially installed in the lower ash hopper.

 

Application industry: Separating particulate dust and fine dust from industrial waste gas, widely used in metallurgy, mining, cement, thermal power plants, building materials, casting, chemical industry, tobacco, asphalt mixer, grain, mechanical processing, boiler dust removal, cement raw materials, clinker mills, cupola, etc.

 

5 Filter cartridge dust collector

 

Under the action of the main fan in the system, the dusty gas enters the gas box at the bottom of the dust collector from the air inlet at the bottom of the dust collector for pre-treatment of the dusty gas, and then enters each dust removal room of the upper box from the bottom; Dust is adsorbed on the outer surface of the filter cartridge, and the filtered clean gas enters the clean air chamber of the upper box through the cartridge and gathers at the air outlet for discharge.

 

As the filtering condition continues, the dust accumulated on the outer surface of the filter cartridge will accumulate more and more, which will correspondingly increase the operating resistance of the equipment. In order to ensure the normal operation of the system, the upper limit of the dust collector resistance should be maintained within the range of 1400-1600pa. When it exceeds this limit range, the PLC pulse automatic controller should issue a command through fixed resistance or timing to perform a three-state dust cleaning.

 

The cleaning process of the filter cartridge dust collector first cuts off the clean air outlet channel of a certain room, making the room in a static state of air flow, and then performs compressed air pulse back blowing cleaning. After cleaning, it undergoes natural settling for a few seconds, and then opens the clean air outlet channel of the room. This not only thoroughly cleans the dust, but also avoids the secondary adsorption of dust generated by spraying the clean dust. In this way, the clean dust is circulated room by room.

 

Application industries: Widely used in tobacco, medicine, food, building materials, light industry, metallurgy, chemical industry, mechanical processing, hardware processing, electronics, pharmaceuticals and other industries.

 

6 Single machine dust collector

 

Dust containing gas enters the box and is filtered by a flat cloth bag filter. The dust is trapped on the outer surface of the filter bag. The purified gas enters the fan through the filter bag and is sucked in and directly discharged by the fan. As the filtration time increases, the dust adhering to the outside of the filter bag also increases, and the resistance of the filter bag also increases accordingly, which affects the dust removal efficiency. At this time, the vibrating mechanism is activated to shake off the dust adhering to the surface of the filter bag, and the dust falling in the drawer is manually pulled out and removed.

 

The working principle of a standalone dust collector:

 

Dust containing gas enters the box through the air inlet and is filtered by a filter bag. The dust is trapped on the outer surface of the filter bag, and the purified gas is discharged from the box through the air outlet by the fan and directly discharged into the indoor environment (or discharged to the outside through an air duct).

 

As the host continues to work, the dust adhering to the outside of the filter bag continues to increase, causing the resistance of the equipment to rise. Therefore, it is necessary to clean the dust to shake off the dust adhering to the outside of the filter bag, which will fall into the dust collector (drawer) through the ash hopper and be manually removed.

 

Application industry: Used for dust removal in industrial dust removal places with low dust removal capacity.

 

7 Multi tube dust collector

 

Dust containing gas enters the gas distribution chamber through the main intake pipe, and then enters the annular gap between the ceramic cyclone body and the guide vane. The guide vanes change the gas from linear motion to circular motion, and the vast majority of the rotating airflow flows downward in a spiral shape from the cylinder to the cone. During the rotation process, the dusty gas generates centrifugal force, which throws dust particles with a density greater than the gas towards the cylinder wall. When dust particles come into contact with the cylinder wall, they lose their inertial force and rely on the momentum of the inlet velocity and downward gravity to fall along the wall face into the ash discharge port and enter the total ash hopper. When the descending external swirling airflow reaches the lower end of the cone, due to the contraction of the cone, it continues to spiral in the same direction of rotation along the axis of the cyclone tube from bottom to top (clean air), passes through the ceramic cyclone exhaust pipe, enters the exhaust chamber, and is discharged from the main exhaust port.

 

Application industry: Suitable for dust control of industrial boilers and thermal power station boilers of various models and combustion methods.

 

8 Electric dust collector

 

The electrostatic precipitator is built on the basis of electrostatic precipitators and dust source control methods, and is a new way to solve the dust removal of small scattered dust points. It uses the exhaust duct or enclosed cover of production equipment as the electrode plate, installs discharge electrodes inside the cover or pipe, and connects to a high-voltage power source to form an electric field. When dusty gas passes through the field, the dust accumulates on the cover or pipe wall under the action of the electric field force, and the purified gas is discharged through the exhaust duct. Although there are many forms of simple electrostatic precipitators, they can be classified into three types: cover type, tube type, and open type. Dust removal relies on manual vibration or self weight shedding.

 

Application industry: Especially suitable for dust purification in crushing, screening workshops, sintering conveyor belts and other scattered dust points, as well as in mine tunnels and small boilers.

 

9 Desulfurization dust collector

 

Dust containing flue gas is passed through stainless steel bulk packing, and the contact surface between the flue gas and aqueous solution is increased to promote the full dissolution and neutralization of the flue gas and spray water, thereby achieving the dust removal, desulfurization, and dust removal effect of the dust collector.

 

Application industry: This type of dust collector is mainly used in all industries such as boilers and kilns that emit smoke and dust.

 

10 Wet dust collector

 

Wet dust collectors can be divided into water storage wet dust collectors, pressurized water spray type, and forced rotation spray type wet desulfurization dust collectors based on their structural types; From the perspective of energy consumption, it can be divided into low energy consumption and high energy consumption; According to the gas-liquid contact type, it can be divided into integral and dispersed contact wet dust collectors.