Regenerating apparatus and method for resist stripping waste liquids

Abstract

The resist stripping waste liquid regenerating apparatus of the invention regenerates a resist stripping waste liquid to obtain a resist stripping regenerated liquid. The apparatus is provided with a membrane separating apparatus which employs a membrane with a molecular weight cutoff of 100-1500 to separate a resist stripping waste liquid into a concentrated liquid and a permeating liquid, an adjusting tank which stores the permeating liquid and adjusts the concentration of an alkanolamine and organic solvent, means for supplying the alkanolamine to the adjusting tank, and means for supplying the organic solvent to the adjusting tank. This construction adequately reduces the resist concentration of the permeating liquid since the resist in the resist stripping waste liquid cannot permeate the membrane. It is thereby possible to lessen the need for dilution of the resist concentration and thus satisfactorily reduce the amount of alkanolamine and organic solvent supplied to the adjusting tank.

Dependencies are inferred from the claim text.