The term "dust removal equipment" refers to equipment for separating dust from flue gas.Dust removal equipment is mainly used in cement, steel, non-ferrous metal, electric power, machinery, chemical industry, waste incineration and other industries with serious dust pollution.The change of the total output value of dust removal equipment industry is closely related to the economic development environment at home and abroad and the development status of downstream industries.Here is a brief description of dust removal equipment classification and principle.
Mechanical dust removal equipment
Mechanical dust removal equipment includes gravity dust removal equipment, centrifugal dust removal equipment and inertial dust removal equipment. The following is a brief introduction of gravity dust removal equipment.
Gravity dust removal equipment is divided into collision type and rotary type. The former is equipped with one or more baffles along the direction of air flow, and dust gas collides to the baffle to separate dust particles from gas.Obviously, the higher the velocity of the gas before hitting the baffle, and the lower the velocity after the collision, the less dust it carries and the higher the dust removal efficiency.The latter causes the dusty gas to change direction several times, separating the dust in the process of turning.The radius of curvature of the gas deflecting is smaller.The higher the steering speed, the higher the dust removal efficiency.
In practical application, inertial dust removal equipment is usually placed in the first level of multi-stage dust removal system, which is used to separate coarse dust.It is especially suitable for collecting dry dust with particle size larger than 10 microns.It is not suitable to remove adhesive dust and fibrous dust.
Washing type dust removal equipment
Washing type dust removal equipment includes water bath type dust removal equipment, bubble type dust removal equipment, venturi tube dust removal equipment, water film type dust removal equipment, etc. The following is a brief introduction of the water bath type as an example.
The working principle of the water-bath dust removal equipment is that the water in the dust removal equipment is sprayed into fog through the nozzle. When the dust and smoke gas passes through the fog space, the dust particles will fall down with the droplets due to the collision, interception and condensation between dust particles and droplets.Advantages of water-bath dust removal equipment: small gaps and orifices are set inside, which can deal with flue gas with high dust concentration without causing blockage, and the filtered water can be recycled until the material concentration in the washing liquid reaches a quite high concentration, simplifying the water treatment facilities;Disadvantages: the equipment volume is large, the ability to handle fine dust is low.Therefore, this type of dust precipitator is often used to deal with the flue gas with large dust diameter and high smoke concentration
Filter type dust removal equipment
Filter dust removal equipment dust removal mechanism is similar to the mask, is through the filter material to the air fly ash particles mechanical interception to achieve, in addition to the first received fly ash particles on the surface of the filter material formed a layer of sticky stable layer, known as filter cake or filter bed, it plays a good role in filtering.The filter element can be made of cotton wool fiber, glass fiber or various chemical fiber through textile (or acupuncture) into filter material, and then sewn into vertically suspended filter bag. Different filter material should be selected for different occasions.Dust collected on the filter bag can be removed by means of periodic mechanical jitter, backblowing of filtered flue gas or pulse backblowing of compressed air.
Iv. Electrostatic dust removal equipment
The working principle of electrostatic dust removal equipment is that when the flue gas passes through the flue pipe in front of the main structure of the electric dust removal equipment, the smoke will be positively charged, and then the flue gas will enter the electric dust removal equipment channel with multi-layer cathode plate.Due to the mutual adsorption between the dust and the cathode plate with positive charge, the dust particles in the flue gas adsorb on the cathode, strike the cathode plate regularly, and make the dust with a certain thickness fall into the dust hopper under the structure of the electric dust removal equipment under the dual effects of self-weight and vibration, so as to achieve the purpose of cleaning the dust in the flue gas.Electric dust removal equipment is mainly used in thermal power plants, the role is to burn stoves or gas boilers in the emission of smoke particles to be removed, to reduce the amount of smoke into the atmosphere, it is to improve environmental pollution, improve air quality of important environmental protection equipment.
Magnetic dust removal equipment
The principle of magnetic dust removal equipment is to use conductive coil to generate magnetic field and absorb magnetic particles, which is mainly used in industrial waste gas such as iron and steel. About 70% of the dust particles in these waste gas have strong magnetism, so magnetic filter can be used to draw magnetic particles out of gas and purify air.