METHOD FOR REGENERATING WASTE SOLVENT

• Main Authors: SAKAMOTO MITSUYOSHI, KAWASE YASUHITO, ODA AKIMASA
• Format: Patent
• Language: English
• Published: 15.10.2002
• Edition: 7
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a new method for regenerating a waste solvent to solve problems of regenerated solvents by unknown cause. SOLUTION: The method for regenerating a waste solvent includes the following processes. (1) The waste solvent is inspected whether it is originally neutral or not. (2) If the solvent is originally neutral, (i) a neutralizer is added to neutralize the solvent and then the solvent is refined by distillation and recovered, or (ii) while a neutralizer is intermittently or continuously added during distillation to carry out neutralization, the solvent is recovered. (3) If the solvent is not originally neutral, (a) the waste solvent is analyzed to determine the quantity of impurities consisting of an acid component or an alkali component and (b) (i) a neutralizer in an amount corresponding to the above quantity is added and the solvent is refined by distillation and recovered or (ii) while an alkali component or an acid component in an amount corresponding to the above quantity is intermittently or continuously added to carry out the neutralization during distillation, the solvent is recovered.