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.Adsorption capacity refers to the amount of adsorbents adsorbed on the adsorbent per unit mass under certain conditions. It is usually expressed in terms of K adsorbents /kg of adsorbent or mass percentage, which is a sign of the adsorption capacity of the adsorbent.
In industry, the amount of adsorption is called the activity of the adsorbent.
The activity of the adsorbent can be expressed in two ways 1) the static activity of the adsorbentUnder certain conditions, the equilibrium adsorption capacity of the adsorbent is its static activity.For a certain adsorption system, the static activity depends only on the adsorption temperature and the concentration or partial pressure of the adsorbed substance.china activated carbon supplier
Dynamic activity of adsorbents。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.activated 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。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.coconut shell based activated carbon
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.
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.