Study On Activated Carbon Fibers Adsorption-nitrogen Desorption And Recover Multi-component VOCs

With the development of industrialization, more and more volatile organiccompounds (VOCs) are discharged to the environment. Due to the increasinglycomplicated sorts and quantities, it causes a serious threat to human health. Then how todeal with the VOCs has received great attention. Currently, treatment methods of VOCsare various. Adsorption technology has been widely adopted because of its advantageswith low energy consumption, high purification efficiency, strong practicability andsuitableness for dealing with low concentrations of VOCs.Four selected organics--ethyl acetate、2-butanone、toluene and butyl acetate are usedin this paper with excellent activated carbon fibers（ACF）as adsorbent, single-specie andmulti-species VOCs were conducted to observe the behavior of adsorption onto ACF,meanwhile, the Langmuir equation and E-L mode were used to predict the experimentalresults. Recovering the organic solvent with a novel hot nitrogen desorption techniqueafter saturation adsorption of activated carbon fibers, and exploring the optimal desorptiontechnical parameters, in expectation of having some guidance reference for engineeringapplications.The results showed that ACF produced by Jiangsu Shunfeng Company has goodadsorption properties. In the experiments of single component adsorption, the break-through time and equilibration time decreased with arising in initial concentration.Langmuir equation was developed to fit the measured adsorption data, and the resultsagree with the measured data. Adsorption amount in descending order are butyl acetate、toluene、ethyl acetate and2-butanone，of which the butyl acetate and toluene are strongadsorbents while the ethyl acetate and2-butanone are weak adsorbents. In the experimentsof four-component adsorption, the break-through time and saturation time decreased witharising in initial concentration. While ethyl acetate and2-butanone concentration jumpedappears in the adsorption process. The four adsorbents adsorption capacity relationship asfollows: butyl acetate>toluene>ethyl acetate>2-butanone.The results of the EL modelpredictions is good fit and are very close to the experimental results, the gap is smaller while raising initial concentration. With the increasing nitrogen temperature and flowcontroller, the efficiency of desorption increases. From the view of energy-saving, thecondition of140℃,2.6m~3/h nitrogen flow, half hour desorption time and ice watercondensation are suggested to be the optimum technological parameter for the thermalnitrogen desorption.