Source: Official website | Date:2019-12-28
Wet dust collectorCommonly known as a "water dust collector", it is a device that closely contacts dusty gases with liquids (usually water), and uses the inertial collision and other effects of water droplets and particles to capture or increase the size of particles.
The main principle of dust removal is that there are two ways in which gas and liquid come into contact in the dust collector: contact with a pre dispersed (atomized or water film) liquid (usually water), or bubbling when the gas impacts the (liquid) layer to form small water droplets or water grinding. For dust particles above 1 μ m, the collision efficiency between dust particles and water droplets depends on the inertia of the particles. When there is relative motion between gas and water droplets, due to the surrounding gas film of water droplets, when the gas approaches the water droplet, the gas flow line will bypass the water droplet and change the direction of flow, and the motion trajectory will change from a straight line to a curve. Meanwhile, dust particles with large particle size and density try to maintain their original flow line and collide with the water droplet. After colliding with the water droplet, the dust particles condense into large particles and are carried away by the water flow. Obviously, the more contact area with the dusty gas (the smaller the diameter of the water droplet, the more water droplets), the higher the collision aggregation efficiency; The higher the density, particle size, and relative velocity of dust particles, the higher the collision aggregation efficiency; The greater the viscosity of gas, the diameter of water droplets, and the surface tension of water, the lower the collision aggregation effect; When the gas contains condensable substances (mainly water), the dusty gas may reach below the dew point after washing, causing the condensable substance to condense with dust particles as the core and cover its surface. When dealing with high-temperature gases (especially those containing hydrophobic dust), the dusty gas can be pre wetted or steam sprayed to improve purification efficiency.
The advantages of wet dust collectors include:
(1) Due to the simultaneous mass and heat transfer processes that occur during the contact between gas and liquid, this type of dust collector not only has the function of dust removal, but also has the function of flue gas cooling and absorbing harmful gases.
(2) Suitable for handling high temperature, flammable and explosive, and harmful gases.
(3) Normal operation and high purification efficiency.
(4) Can be used for dust and gas accumulation in mist and dust.
(5) Measurement of exhaust volume.
(6) Simple structure, small footprint, and low investment.
(7) Safe operation, convenient operation and maintenance.
The disadvantages of wet dust collectors include:
(1) The mud discharged from the wet dust collector needs to be treated, otherwise it will cause secondary pollution.
(2) When purifying corrosive gases, chemical aggressiveness is transferred to water, so the sewage system needs to be protected with anti-corrosion materials.
(3) Not suitable for hydrophobic smoke and dust; For sticky smoke and dust, it is easy to cause blockages in pipes, blades, etc.
(4) Compared to dry dust collectors, they require water consumption and are difficult to treat. Therefore, anti freezing measures should be taken in severely cold areas.