Three-waste treatment system in laboratory
Laboratory waste gas treatment
In the process of inspection, identification and testing in the laboratory, various waste gases will be generated due to the needs of the experiment, and the waste gas components are relatively complex, including aromatics: benzene, toluene, xylene, styrene, etc.; ketones: acetone, cyclohexane Ketones, methyl ethyl, etc.; lipids: ethyl acetate, butyl acetate, methyl acetate, banana water, etc.; alcohols: methanol, ethanol, butanol, isopropanol and other organic waste gases. It also includes inorganic waste gas such as nitrogen oxides, sulfuric acid mist, hydrogen chloride, hydrogen fluoride, hydrogen sulfide, and sulfur dioxide; at the same time, there are also high-temperature combustion waste gas and dust. The waste gas generated during the experiment is often characterized by complexity and diversity in cost, and the degree of damage to human health is also different. In order to better solve the impact of organic solvents and organic waste gas on human beings.
Spray scrubber mechanism and working principle:
The spray washing tower is mainly composed of the main cylinder, the upper spray disc, the middle packing, the lower spray disc, the cleaning hole, the sight glass hole, etc. Its working principle is: under the negative pressure of the induced draft fan, the exhaust gas flow is sucked into The air inlet pipe is sent into the tower body. The main body of the tower is a circular cylinder, and the washing liquid (sodium hydroxide solution) is injected into the cylinder from the upper spray plate of the washing tower, so that the packing of the whole cylinder is mixed with water to form a mist-like washing liquid water film from top to bottom. Flow (the filler keeps rolling under the action of the airflow, so that the exhaust gas and the washing liquid are fully mixed). Under the action of negative pressure, the exhaust gas rotates and rises in the cylinder, and always rubs against the water film of the washing liquid in the cylinder, so that the acid gas is fully wetted and neutralized by the water film of the washing liquid. There is a cleaning hole at the bottom of the cylinder to facilitate the cleaning of the bottom of the cylinder, and the washing liquid is continuously circulated through the liquid storage tank (water tank) under the action of the water pump, so as to achieve the effect of eliminating exhaust gas.
Adsorption of activated carbon:
The adsorption of activated carbon can be divided into physical adsorption and chemical adsorption.
Physical adsorption: mainly occurs in the process of activated carbon to remove impurities in the liquid and gas phases. The porous structure of activated carbon provides a large amount of surface area, making it very easy to absorb and collect impurities. Just like magnetism, all molecules are attracted to each other. Because of this, a large number of molecules on the pore wall of activated carbon can generate a strong attraction, so as to achieve the purpose of attracting the impurities in the meson into the pore size.
It must be pointed out that the molecular diameter of these adsorbed impurities must be smaller than the pore size of the activated carbon, so as to ensure that the impurities are absorbed into the pore size. That's why we create activated carbons with different pore structures by constantly changing the raw materials and activation conditions, which are suitable for various impurity absorption applications.
Chemisorption: In addition to physical adsorption, chemical reactions often occur on the surface of activated carbon.
Activated carbon not only contains carbon, but also contains a small amount of oxygen and hydrogen in the form of chemical bonds and functional groups on its surface, such as carboxyl, hydroxyl, phenols, lactones, quinones, ethers, etc. The oxides or complexes contained on these surfaces can chemically react with the adsorbed substances, and thus combine with the adsorbed substances and aggregate to the surface of the activated carbon.
The adsorption of activated carbon is the result of the combined effect of the above two kinds of adsorption.
中文
