The purification efficiency of liquid absorption method is 60%~ 80%, which is suitable for treating low concentration and large volume of organic waste gas, but there are secondary pollution.
The purification rate of catalytic combustion method is 95%, which is suitable for the treatment of high concentration and small air volume organic waste gas. The disadvantage is that it has strict requirements on the treatment object and requires high gas temperature. In order to improve the exhaust gas temperature, it needs to consume a lot of fuel, so the operation cost is very high.
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.The experimental results show that the surface structure of the activated carbon material modified by FeSO changes: the specific surface area decreases, the surface oxygen content increases, the plane of the random layer graphite carbon net is destroyed to a certain extent, and the ammonia absorption capacity and benzene absorption performance of the sample are greatly enhanced.He ChunHong et al. [reported the research progress of supporting activated carbon materials in the removal of SO; the removal ability of SO was significantly enhanced after supporting Co, Ni, Mg, and V compounds, which was due to the formation of Co(OH)2, Ni(OH)2, Mg (OH)2, and V,0 microcrystals on the surface of activated carbon after supporting, which enhanced the desulfurization activity of activated carbon.The structural characteristics mainly refer to the micropore volume, specific surface area and micropore structure, etc. Ordinary activated carbon has high ash content, small pore volume, wide distribution of micropores, small specific surface area and poor adsorption performance yrd activated carbon
The physical properties of activated carbon, such as specific surface area and pore size distribution, have great influence on its adsorption capacity.
At present, there are three methods to modify surface structural characteristics: physical method, chemical method and physical-chemical combination method, the latter two methods are more commonly used.The micro-structure of activated carbon can be achieved by microwave heating, neutron radiation and low temperature plasma technology.bulk activated carbon pellets