Title:
METHOD FOR CONCENTRATING TETRAALKYLAMMONIUM HYDROXIDE WASTE LIQUID
Document Type and Number:
Japanese Patent JP3766629
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a concentration method to obtain a tetraalkylammonium hydroxide (TAAH) waste liquid of high concentration by supplying a waste liquid containing a tetraalkylammonium hydroxide of low concentration obtained as a waste liquid by development of a photoresist or the like to a falling thin film evaporator and efficiently and easily concentrating the liquid.
SOLUTION: In the process of supplying a tetraalkylammonium hydroxide waste liquid to a falling thin film evaporator to concentrate, the thickness (T1) of the liquid film at the lower end of the heating face of the falling thin film evaporator is controlled to 0.1 to 1.2 mm so as to prevent foaming on the heating face and to prevent accumulation of air bubbles. Concentration of the waste liquid containing the tetraalkylammonium in the falling thin film evaporator is preferably carried out under reduced pressure, particularly preferably under the pressure of 100 to 200 Torr.
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| JPS5581776 | DECHLORINATION DEVICE OF SEAWATER OR BRINE |
| JPS5855078 | DRYER FOR THIN FILM |
Inventors:
Yoshifumi Yamashita
Mochizuki Soichi
Kazumasa Oka
Mochizuki Soichi
Kazumasa Oka
Application Number:
JP2001367213A
Publication Date:
April 12, 2006
Filing Date:
November 30, 2001
Export Citation:
Assignee:
Tokuyama Corporation
International Classes:
C02F1/08; G03F7/32; B01B1/02; B01D1/22; H01L21/027; (IPC1-7): C02F1/08; B01B1/02; B01D1/22; G03F7/32; H01L21/027
Domestic Patent References:
| JP10053568A | ||||
| JP8325767A | ||||
| JP63126001U | ||||
| JP2003164858A |