A temperature swing method VOC concentration and a low-temperature liquefied VOC recovery method in which moisture is removed using an adsorbent and cold energy is recovered.

摘要

PPROBLEM TO BE SOLVED: To provide a VOC recovering method by low temperature VOC condensation following the removal of moisture after performing volume reduction/concentration on a treated gas in a temperature swinging VOC absorption apparatus. PSOLUTION: VOC is adsorbed at a low temperature by the temperature swinging VOC adsorption apparatus; nitrogen is desorbed as a purge gas at a high temperature; after volume reduction/concentration is performed on the treated gas, nitrogen containing VOC and moisture is pressurized and is introduced into a moisture selective-type adsorbent adsorption towers 15a, 15b to remove the moisture. Liquefaction recovery is performed on VOC at a low temperature; cold is recovered from dry nitrogen after the recovery; then the adsorption tower after the moisture is adsorbed is decompressed to adsorb and remove the moisture and a heat retentive cold recovery is performed using the dry nitrogen as a countercurrent purge gas; and after the moisture is removed from nitrogen that is allowed to flow for filtration, the nitrogen is reflux-recycled as a purge gas. As a VOC selective-type adsorbent 5, one kind or more are selected from the group consisting of silica lite, USM, , USY, MSP, and, as a moisture selective-type adsorbent 16, one kind or more are selected from the group consisting of K-A, Na-A, Na-K-A and Ca-A. PCOPYRIGHT: (C)2010,JPO&INPIT