METHOD FOR TREATING WASTE WATER AT THE TIME OF RECOVERING VOLATILE ORGANIC COMPOUND

PROBLEM TO BE SOLVED: To provide a efficient and economical waste water treating method of the waste water containing a volatile organic compound generated at the time of separating/recovering the volatile organic compound by using adsorption and to reduce the burden of post treatment by reducing a concentration of the volatile organic compound remaining in the waste water. SOLUTION: In the recovering method of the volatile organic compound in which the compound is desorbed by steam from an adsorbent, after cooling the desorbing steam, a volatile organic compound phase and a water phase are separated, and the separated water is introduced into a column from the upper part of a packed column in which >=2 packed layers divided with a gas back flow preventing plate are formed, and purging steam is introduced from the lower part of the column to diffuse the volatile organic compound by subjecting the water and the purging steam to counter flow contact in the state at which gas phase is a continuous phase, and the obtained purging steam containing the volatile organic compound is returned to a cooling stage for the desorbing steam.