The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 10, 2012
Filed:
Aug. 20, 2009
Masayuki Kamikawa, Hitachinaka, JP;
Toshiaki Matsuo, Mito, JP;
Naruyasu Okamoto, Tokyo, JP;
Kenichiro Oka, Mito, JP;
Takeyuki Kondo, Hitachi, JP;
Masayuki Kamikawa, Hitachinaka, JP;
Toshiaki Matsuo, Mito, JP;
Naruyasu Okamoto, Tokyo, JP;
Kenichiro Oka, Mito, JP;
Takeyuki Kondo, Hitachi, JP;
Hitachi Plant Technologies, Ltd., Tokyo, JP;
Abstract
An equipment for producing polyhydroxycarboxylic acid, includes a ring-opening polymerization apparatus, a liquid phase devolatilizing apparatus, and a drying apparatus, wherein an indirect heat exchanger is connected to a vent gas discharge path of the liquid phase devolatilizing apparatus. The indirect heat exchanger captures a dispersed in-process substance containing hydroxycarboxylic acid cyclic dimers and transfers the substance to the ring-opening polymerization apparatus; a wet condenser and a hot well are connected to a vent gas discharge path of the indirect heat exchanger and that of the drying apparatus, respectively. The wet condenser captures a dispersed in process substance containing the cyclic dimers with the use of a refrigerant containing hydroxycarboxylic acid corresponding to the cyclic dimers and transfers the substance to the hot well; the hot well causes hydrolysis of the cyclic dimers for generation of hydroxycarboxylic acid; the generated hydroxycarboxylic acid is mixed with a refrigerant and the mixture is circulated to the wet condenser; and hydroxycarboxylic acid is highly concentrated via circulation between the wet condenser and the hot well and then discharged.