Because of these pores, especially the micropores provide a large surface area.The pore volume of activated carbon micropores is generally only 0.25-0.9mL/g, the number of pores is about 1020 lg, and the surface area of all micropores is about 500-1500m2/g, which is usually measured by the BET method, and it is also said to be as high as 3500-5000 m2/g.Activated carbon almost more than 95% of the surface area is in the micropore, so in addition to some macromolecules can not enter, micropore is an important factor to determine the adsorption performance of activated carbon.wanyang active carbon
The pore volume of mesopores is generally about 0.02-1.0 MLLg, and the surface area can be up to several hundred square meters, generally only about 5% of the total activated carbon silkworm species.
Principle of activated carbon adsorptionactivated carbon is a kind of very small granular has a large surface area, and more tiny holes in the granular – capillary. The capillary has very strong adsorption capacity, due to the granular surface area is large, so a good contact with with gas (impurities). When these gases (impurities) encounter capillary by adsorption, purification effect. Activated carbon surface area of the study is very important, only the BET specific surface area detecting data of active carbon method detected result is reliable, domestic at present there are many instruments can only make direct comparison method of detection granular activated carbon
In domestic has been eliminated. Specific surface area test unified the multi-point BET method at home and abroad, specific surface area measurement standards are developed at home and abroad is based on BET test method, please see our national standard (GB/T 19587-2004) – gas adsorption BET principle of solid material specific surface area measurement methods. Specific surface area testing is actually the more time-consuming jobs, as the adsorption capacity of sample is different, some sample testing may need to spend the whole dayTime, if the test process is not fully automated, the tester can not leave at any time, and should be highly focused, observe the dashboard, control the knob, a little careless will lead to the failure of the test process, which will waste a lot of valuable time of the tester.The purification efficiency of activated carbon adsorption method is 99.2%~99.3%. For the treatment of large air volume and low concentration of organic waste gas, it is agreed that this method is the most mature and reliable technology at home and abroad, but the T art process is too long, the operation cost is high, and it is often more difficult to need a stable steam source.In view of these problems, combined with the characteristics of this graduation design and only body requirements, the use of activated carbon fixed bed adsorption system for industrial organic waste gas purification, the selection of honeycomb activated carbon as adsorbent.The process system is compact and integrated with adsorption and desorption.
The waste gas produced in the production process, mainly of benzene, toluene, xylene, etc., according to the nature of benzene class, this scheme adopts the active carbon as adsorbent to absorb the waste gas, the adsorption bed configuration 2 sets of above commonly, use rotation, when one adsorption bed adsorption of organic adsorption amount of reach regulation, change to another Ⅰ adsorption bed for adsorption purification operation, at the same time to take off one in front of the adsorption bed with regeneration.Desorption is carried out by heating under the action of additional steam, and most of the hotgas released by the tail gas is used for desorption and regeneration of adsorbent in the adsorption bed to achieve the utilization of waste heat.The waste gas volatilized from production is sent to the adsorption tower by centrifugal fan with activated carbon as adsorbent. The gas in the tower is processed through the activated carbon filter layer from right to left and from bottom to top, and the purified gas is discharged into the atmosphere through the exhaust pipe.
