Method for adsorbing harmful substance

A method for treating gases containing harmful substance by using an apparatus provided with at least two adsorptive units composed of at least one adsorptive tubular element made of a fibrous sheet of adsorptive material having a 0.1 m/second pressure loss of not more than 15 mm Aq/cm, said adsorptive material consisting predominantly of active carbon fibers having an equilibrated adsorption amount of benzene of not less than 300 mg/g and an adsorption rate constant of benzene of not less and 0.2/minute, and the ratio of the area of said adsorptive material to the area of the unit frame being not less than 2, which comprises

• passing gases contaminated with the harmful substances through the adsorptive element in one of said adsorptive units, thereby adsorbing the harmful substances with said adsorptive material to recover a purified gas, and
• forcibly passing a heated purging gas through the adsorptive element in another one of the adsorptive units where the harmful substance had been previously adsorbed, said heated purging gas being jetted from a heated purging gas jetting device provided at the upper part of the adsorptive element in said another adsorptive unit, whereby the harmful substance-adsorbed by the adsorptive element is heated and desorbed,
• said adsorptive units being sequentially used for adsorption and desorption, respectively