The destruction scheme mainly includes catalytic combustion device (RCO), regenerative combustion device (RTO) and low temperature plasma.
Water spraying method
Water spraying method is widely used. Its principle is to separate pollutants from clean gas by spraying water on waste gas to make water-soluble or large particles settle. Take the pump-free water curtain painting room as an example. Pump-free water curtain spray booth uses air to induce water pumping to form circulating water curtain. When workers spray paint on the surface of the workpiece facing the water curtain, the air containing paint mist collides with the water curtain and enters the gas-water channel through the water curtain, which is strongly mixed with the water in the channel. When it enters the gas collection box, the flow rate suddenly decreases and the gas and water are separated. After the air passes through the water baffle, it is pumped into the activated carbon adsorption device by the fan. The separated water is collected by the gas collecting box and flows into the overflow tank, from which the water overflows onto the flashing plate to form a water curtain and flows back to the water tank. In this process, the paint mist forms a slag block, thereby absorbing and removing paint particles.
adsorption method
Activated carbon adsorption is a common waste gas treatment method. Adsorption method uses porous activated carbon, silica bath soil, anthracite and so on to adsorb organic gas molecules to its surface, thus purifying.
Advantages: high purification rate (activated carbon adsorption can reach more than 99%), wide application, simple operation and low investment.
Disadvantages: the wind pressure loss of the system is large, which makes the energy consumption high, the saturation point of adsorbent is difficult to grasp, the capacity of adsorbent is limited, and the operation dosage is high.
Separation method
Cut-off method, through special filter materials, is placed in the process of exhaust gas discharge and cut off by machines, thus achieving management effect.
Advantages: high compliance with paint mist management, no skill requirements and simple operation.
Disadvantages: poor performance in removing organic matter.
combustion method
Through high temperature heating, the organic waste gas is directly burned to achieve the purpose of waste gas purification.
Advantages: high purity, up to more than 95%.
Disadvantages: a lot of heat energy is needed. For example, the direct combustion of toluene needs about 800 degrees, which inevitably consumes a lot of energy and easily causes secondary pollution at high temperature.
Suction method
Through the mutual reaction between the absorption liquid and the waste gas, harmful substances in the waste gas are dissolved in the absorption liquid, so that the waste gas can be purified. Absorbed liquid will be punished separately.
Advantages: small investment, low operating cost and simple operation.
Disadvantages: the punishment for disposal is low and unstable, and the compliance of purification is not high, about 50%, so it is difficult to meet the requirements of environmental protection. There is secondary pollution for low concentration organic waste gas.
Condensation method
Through condensation and cooling, when the temperature is lower than the freezing point of harmful substances, the gaseous harmful substances are transformed into liquid and diffused out of the atmosphere, thus purifying.
Advantages: stable operation and high purification compliance.
Disadvantages: large investment, high requirements for the situation and operators, excessive energy consumption and high operating costs.