Chimney exhaust white smoke purification achieves effective removal of pollutants in flue gas and reduces white smoke emissions through the synergistic effect of multiple core technologies. Its technologies cover multiple fields such as physics, chemistry and biology, and each technology plays a role in different pollutant characteristics and purification needs.
Condensation technology is the basic means of treating white smoke. The main component of white smoke discharged from the chimney is water vapor. When the high-temperature flue gas is discharged and encounters cold air, it quickly condenses into small water droplets, forming a white smoke-like shape. Condensation technology reduces the temperature of flue gas, so that the water vapor in it further condenses into liquid water and separates it. The condensation device set in the equipment uses the principle of heat exchange to transfer the heat of high-temperature flue gas to the cooling medium, prompting the condensation of water vapor. The condensed water droplets are separated from the flue gas by gravity sedimentation or mechanical separation, thereby reducing the water content in the flue gas and reducing the generation of white smoke. This technology can not only reduce the visual pollution of white smoke, but also remove some water-soluble pollutants, playing a preliminary purification role.
Adsorption technology plays an important role in the purification process. This technology uses adsorption materials with high specific surface area and porous structure, such as activated carbon and molecular sieve, to adsorb harmful components in flue gas. The rich pores and strong adsorption force on the surface of activated carbon can effectively adsorb odor substances, organic pollutants and some heavy metal ions in flue gas. Molecular sieves can selectively adsorb pollutants of specific molecular sizes due to their regular crystal structure and unique pore size. During the adsorption process, pollutant molecules adhere to the surface of the adsorption material to purify the flue gas. When the adsorption material reaches saturation, its adsorption capacity can be restored through regeneration treatment, which can be reused, improve purification efficiency and reduce operating costs.
Washing technology is also a common core purification method. It removes pollutants from flue gas by allowing the flue gas to fully contact with the washing liquid and utilizing the solubility or chemical reaction of the pollutants in the washing liquid. For example, for flue gas containing acidic pollutants, alkaline washing liquid can be used for neutralization reaction to convert the acidic gas into salt substances dissolved in the washing liquid; for particulate matter, the washing liquid is used to flush and wet the particulate matter to agglomerate and settle. The scrubbing equipment usually adopts the form of spray tower, packed tower, etc. By rationally designing the structure and spraying method in the tower, it is ensured that the flue gas and the scrubbing liquid are fully mixed and contacted, and the removal efficiency of pollutants is improved. At the same time, the scrubbing liquid can be recycled after treatment to reduce water resource waste and secondary pollution.
Catalytic oxidation technology can efficiently treat complex pollutants in flue gas. This technology uses the catalytic effect of the catalyst to reduce the activation energy of the chemical reaction, so that the harmful components in the flue gas react with the oxidant at a lower temperature and convert them into harmless or less harmful substances. For example, for nitrogen oxides in flue gas, they can undergo selective catalytic reduction reaction with ammonia under the action of the catalyst to generate nitrogen and water; for volatile organic compounds, they can be converted into carbon dioxide and water through catalytic oxidation reaction. The performance of the catalyst directly affects the reaction efficiency and purification effect. Therefore, it is necessary to select a catalyst with high activity, good stability and strong anti-poisoning ability, and accurately control the reaction temperature, gas flow rate and other conditions to ensure the efficient progress of the catalytic oxidation process.
Electrostatic dust removal technology has a significant purification effect on particulate matter in flue gas. The principle is to use a high-voltage electric field to charge the particles in the flue gas. The charged particles move to the electrode and are captured under the action of the electric field force. The electrostatic precipitator consists of a discharge electrode, a dust collecting electrode and a high-voltage power supply device. The discharge electrode generates corona discharge, which ionizes the surrounding gas to produce a large number of ions. The particles collide with the ions and are charged. Then, under the action of the electric field force, they move to the dust collecting electrode and deposit on the electrode plate. Regularly vibrating or flushing the dust collecting electrode can remove the collected particles and ensure the continuous and stable operation of the equipment. This technology has a high removal efficiency for fine particles and can effectively reduce the suspended solids in white smoke.
Chimney exhaust white smoke purification provides a green solution for white smoke purification. This technology uses the metabolism of microorganisms to convert organic pollutants and some inorganic pollutants in flue gas into harmless substances. In biological treatment devices such as biofilters or biotrickling filters, filter materials containing microorganisms are filled. When the flue gas passes through the filter material layer, the pollutants are adsorbed and decomposed by microorganisms. Microorganisms can continue to play a purification role under suitable environmental conditions, such as suitable temperature, humidity, and nutrient supply. Biological purification technology has the advantages of low energy consumption, low operating costs, and low secondary pollution, but it has certain requirements for the types and concentrations of pollutants and is usually suitable for treating low-concentration, biodegradable pollutants.
Various core purification technologies do not work independently, but cooperate with each other and complement each other. In practical applications, according to the flue gas characteristics and emission requirements of different industries, multiple technologies are combined to form an efficient purification system, thereby achieving comprehensive purification of chimney exhaust, reducing white smoke emissions, meeting environmental protection standards, and playing an important role in improving the quality of the atmospheric environment.
