Exhaust gas treatment equipment mainly refers to an environmental protection device that uses different process technologies to recover, remove, and reduce harmful components in exhaust emissions, in order to protect the environment and purify the air, so that our environment is not polluted.
Exhaust gas treatment equipment mainly refers to an environmental protection device that uses different process technologies to recover, remove, and reduce harmful components in exhaust emissions, in order to protect the environment and purify the air, so that our environment is not polluted.
Classification of equipment for exhaust gas treatment
absorption equipment
The absorption method uses low volatile or non-volatile solvents to absorb VOCs, and then separates them based on the differences in physical properties between VOCs and absorbents.
The gas containing VOCs enters the absorption tower from the bottom and comes into contact with the absorbent from the top of the tower in reverse flow during the upward process. The purified gas is discharged from the top of the tower. After absorbing VOCs, the absorbent enters the top of the stripping tower through a heat exchanger and desorbs under conditions where the temperature is higher than the absorption temperature or the pressure is lower than the absorption pressure. The desorbed absorbent is condensed by a solvent condenser and returned to the absorption tower. The extracted VOCs gas passes through the condenser and gas-liquid separator before leaving the stripping tower as relatively pure VOCs gas, which is then recycled and reused. This process is suitable for gas purification with high VOCs concentration and low temperature, and requires corresponding process adjustments in other situations.
ADSORPTION EQUIPMENT
When treating fluid mixtures with porous solid materials, a certain component or components in the fluid can be adsorbed onto the surface and concentrated on it, which is called adsorption. When adsorbing and treating exhaust gas, the adsorbed object is gaseous pollutants, gas-solid adsorption. The adsorbed gas component is called adsorbate, and the porous solid material is called adsorbent.
After the solid surface adsorbs the adsorbate, a portion of the adsorbed adsorbate can detach from the adsorbent surface, which is now attached. After a period of adsorption, due to the concentration of surface adsorbates, their adsorption capacity significantly decreases and the requirements for adsorption purification are met. At this time, certain measures need to be taken to desorb the adsorbates already adsorbed on the adsorbent to enhance its adsorption capacity. This process is called adsorbent regeneration. Therefore, in practical adsorption engineering, it is the cycle of adsorption regeneration and repeated adsorption that is used to remove pollutants from the exhaust gas and recover useful components from the exhaust gas.
Purification equipment
The combustion method is very effective in treating high concentrations of VOC and odorous compounds. Its principle is to burn these impurities with excess air, most of which generate carbon dioxide and water vapor, which can be emitted into the atmosphere. However, when dealing with organic compounds containing chlorine and sulfur, the combustion products of HCl or SO2 require further treatment of the post combustion gases.
Governance equipment
Plasma is a gas in an ionized state, and its English name is plasma. It was named by American scientist Muir in 1927 when studying the discharge phenomenon in mercury vapor at low pressure. Plasma is composed of a large number of electrons, neutral atoms, excited state atoms, photons, and free radicals, but the number of charges of electrons and positive ions must exhibit electrical neutrality, which is the meaning of "plasma". Plasma differs from solids, liquids, and gases in many aspects of conductivity and electromagnetic influence, hence it is also referred to as the fourth state of matter. According to the state, temperature, and ion density, plasmas can usually be divided into high-temperature plasmas and low-temperature plasmas (bulk and cold plasmas). The ionization degree of high-temperature plasma is close to 1, and various particles have almost the same temperature and are in thermodynamic equilibrium. It is mainly used in the study of controlled thermonuclear reactions. Low temperature plasma, on the other hand, is in a non-equilibrium state where the temperatures of various particles are not the same. The electron temperature (Te) is greater than or equal to the ion temperature (Ti), reaching over 104K, while the temperature of its ions and neutral particles can be as low as 300-500K. Generally, gas electron emitters belong to low-temperature plasmas.
