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.Microwave modification is to control the surface chemical composition or element content of activated carbon by adjusting the microwave power and radiation time, so as to adjust the surface chemical properties of activated carbon and improve the adsorption performance of activated carbon. It is an effective method to change the adsorption performance of activated carbon.Some studies have found that after the activated carbon by microwave irradiation, the surface become rough, is in the shape of concave and convex, many backwater hole was opened and extends into, the pores attachments to be removed, the carbon skeleton to contract, different size of hole shrinkage, jung, entrance to drop, pore size distribution in the direction of microporous migration, thus effectively improve the adsorption ability of active carbon, enhance the adsorption ability of refractory organic matterThe waste gas produced in the production process, mainly of benzene, toluene, xylene, etc., according to the nature of benzene class, yrd activated carbon
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.China's activated carbon production coal is mainly concentrated in the northwest region, there are long bituminous coal, weak viscous coal and anthracite, due to the single coal properties of the restriction, China's coal-based activated carbon products are mostly in the middle and low grade products.Coal based activated carbon production in China, starting in the 1950 s, but slow to develop early in the early 1980 s the national annual production of about 4 000 t [2 l. Along with the reform and opening up, economic development and the gradual improvement of the people's living standard and increasing efforts in environmental protection at home and abroad in recent years, domestic demand of activated carbon, and exports continue to increase, coal based activated carbon industry is developing rapidly. In the late 80 s, China's coal-based activated carbon produced more than 20000 tons, in 2000 reached 100000 tons, 400000 tons in 2008 or so,China has basically formed an independent, complete and initial industrial system for the preparation of activated carbon, and has become the world's largest producer of coal-based activated carbon.Due to the advantages of coal resources and product price, China's coal-based activated carbon products have a strong competitiveness in the international market.bulk activated carbon pellets