Detailed Explanation of Steam Boiler System Dust Collector

As we all know, solid fuel will produce a lot of dust when it is burned. If the flue gas produced is directly discharged into the air, it will cause serious pollution to the surrounding environment. Solid fuel steam boilers need to be equipped with corresponding dust collector to reduce pollution to the surrounding environment.

At present, the common special dust collector for boilers are:

1. Multi-tube dust collector.

2. Wet dust collector.

3. Bag dust collector.

The following will give you a detailed introduction to the working principles, advantages, and disadvantages of these types of dust collectors.

1. Multi-tube Dust Collector

Working Principle:

1. The dust-containing gas enters the dust collector, passes through the ceramic guide, and rotates at high speed inside the cyclone.

2. Under the action of centrifugal force, dust and gas are separated, and the dust falls in the dust collection box and is discharged through the ash discharge valve.

3. The purified gas forms an ascending swirling flow merges into the gas collection chamber through the exhaust pipe and is discharged from the chimney through the outlet to achieve the dust removal effect.

4. This kind of dust collector is currently the main supporting equipment for the steam boiler system.

advantage:

1. Equipment investment and operating costs are low.

2. It has the advantages of corrosion resistance, wear resistance, high-temperature resistance, non-clogging, long service life, simple operation, and no secondary pollution.

3. The multi-tube cyclone dust collector has high efficiency and large gas volume.

4. Set up a rainproof shed, which is strong and durable.

2. Wet dust collector

Generally used with a multi-tube dust collector.

Working Principle:

The dust-containing gas is in close contact with the liquid (usually water), using the inertial collision of water droplets and particles, the water and dust are fully mixed to form new particles, and the weight of the particles is continuously increased. Under the gravity of the particles, the dust stays in the fixed container. Achieve the separation effect of air and dust.

advantage:

1. It can effectively separate dust with a diameter of 0.1-20 microns from the airflow, and at the same time, it can also remove some gaseous pollutants. It can process 5 to 7 cubic meters of dusty airflow per second. It covers an area of about 4 square meters and consumes about 1 ton/hour of water.

2. It can handle high-temperature and high-humidity airflow to minimize the possibility of fire and explosion.

3. Suitable for processing high temperature. High temperature, flammable, explosive and harmful gas;

4. Normal operation, high purification efficiency;

5. Dust and gas that can be used for fog and dust accumulation;

6. Exhaust volume constant;

7. Simple structure, small area, low investment;

8. Safe operation, convenient operation, and maintenance.

Disadvantages:

⑴ The mud discharged of the wet dust collector must be treated, otherwise it will cause secondary pollution;

⑵ When purifying corrosive gases, the chemical corrosivity is transferred to the water, so the sewage system should be protected with anti-corrosion materials;

⑶ Not suitable for hydrophobic smoke and dust; for sticky smoke and dust, it is easy to block pipes, blades, etc.;

⑷Compared with dry dust collectors, they need to consume water and deal with difficult problems. Antifreeze measures should be adopted in severe cold areas.

3. Bag Dust Collector

Work Principle.

1. The gas containing dust enters the air inlet pipe from the lower part of the dust collector.

2. When it enters the ash hopper through the deflector, the coarse dust will fall into the ash hopper due to the effect of the collision of the deflector and the reduction of the gas velocity. 

3. The rest of the fine particle dust enters the bag chamber with the gas, and the dust will be kept in the bag due to the effect of inertia, diffusion, blocking, hooking, and static electricity of the filter fiber and fabric. 

4. The purified gas escapes out of the bag, Discharged through the exhaust pipe.

5. The accumulated dust on the filter bag is removed by gas backwash, and the cleared dust is lowered to the ash hopper and discharged to the ash transfer device through the double layer ash discharge valve.

6. The cleared dust is discharged by the ash discharge device.

Advantages.

(1) High dust removal efficiency, generally above 99%, the dust concentration of the outlet gas of the precipitator is within tens of mg/m3, and it has high grading efficiency for fine dust of sub-micron particle size.

(2) Wide range of air handling capacity, from a few m3 in 1min for small ones to tens of thousands m3 in 1min for large ones, which can be used for the flue gas dedusting of industrial furnace, reducing the emission of air pollutants.

(3) Simple structure, easy maintenance, and operation.

(4) Under the premise of ensuring the same high dust removal efficiency, the cost is lower than that of an electric dust collector.

(5) When glass fiber, PTFE, P84, and other high-temperature resistant filter media are used, it can be operated under high-temperature conditions above 200℃.

(6) Insensitive to the characteristics of the dust, not affected by the dust and resistance.

Dust collector installation points.

a) Pay attention to the collision in the process of transportation and installation, and make sure to hold lightly.

b) In the installation, all flanges and flange connections need to clip the asbestos rope in the middle and bolted tight with bolts to prevent air leakage, affecting the efficiency of dust collection.

(c) After it is put into use, the dust must be removed on time, generally not more than once every 4 hours, in order to prevent excessive dust collection in the dust collection box.

d) the design of the user should be based on the boiler exhaust volume, flue gas flow, supporting the use of dust collectors, and provide the user boiler dust collector surrounding space.

e) When discharging ashes, the draught fan must be turned off first, and the ash outlet is forbidden to be struck with an iron clock to check frequently whether the ash outlet is sealed.