Nippon Shokubai Co., Ltd.

Kazuto Okazaki

Yukihiro Matsumoto

Kazuhiko Sakamoto

Osamu Dodo

Takeshi Nishimura

Sei Nakahara

Hiroo Iwato

Kiyotaka Watanabe

Yuji Miyahara

Chilled coolant is prepared by liquid coolant utilizing the latent heat generated by a gasification of liquefied propylene, for example, and this chilled coolant is used in heat exchangers which are used in a process for production of acrylic acid or acrolein. This method allows effective utilization of the latent heat which used to be discarded and permits a reduction of energy consumption of cooling required separately in the step for production. By recovering the chilled coolant with the liquid coolant, it makes possible to stabilize the gasification of propylene, etc. and consequently stabilize the production of acrylic acid. This invention consists of providing the method for the production of acrylic acid, etc. and the apparatus which make effective use of the latent heat generated in the steps of production.

Method for production of acrylic acid and apparatus for production of acrylic acid

An apparatus for the treatment of a waste gas that is capable of recovering the heat generated by the catalytic oxidation of a waste gas to the largest possible extent and allowing the temperature of the treated gas in a first waste gas pre-heater to be adjusted to an arbitrary level incapable of condensing moisture and/or corrosive gas is provided. The apparatus for the treatment of the waste gas includes a molecular oxygen-containing gas supplying device, second to n'th waste gas pre-heaters, a heat-recovering device, and a reactor.

Apparatus for treatment of waste gas

A method for producing an unsaturated carboxylic ester is provided, which can prevent the raw material compounds and the product of the reaction from splashing and adhering on the inner wall of the reaction vessel and succumbing to polymerization on the inner wall. Specifically, it is characterized by the fact that the difference between the outer periphery of the reaction vessel heated by the heating means and the reaction solution in temperature is not higher than 80&#xb0; C.

Method for production of unsaturated carboxylic ester

The present invention provides a heat-exchanging method for an easily polymerizable compound which method effectively prevents polymerization in a heat exchanger to enable a long-term stable heat exchange when an easily polymerizable liquid compound (for example, acrylate ester) or an easily polymerizable compound-containing liquid (for example, aqueous acrylic acid solution) is heat-exchanged. A vertical spiral type heat exchanger with a fluid path space of not less than 6 mm is used as a heat exchanger to carry out the heat exchange under conditions where the average liquid flow rate is not less than 0.2 m/sec and where the liquid residence time is not more than 100 seconds.

Heat-exchanging method for easily polymerizable compound

Disclosed is a method of removing heavy metals contained in exhaust gas which has been generated by burning a waste liquid containing the heavy metals discharged in a process of producing organic compounds. The method includes the steps in the order of: (a) a combustion step of burning the waste liquid to produce exhaust gas; (b) a gas-liquid contact step of rendering a liquid containing an alkali compound in contact with the exhaust gas to collect the heavy metals in bottoms of the liquid; and (c) a coagulating step of adding a coagulant to the bottoms to coagulate the heavy metals in the bottoms for removal of the heavy metals. According to this method, the heavy metals contained in the exhaust gas can be efficiently separated and removed.

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Himeji, Japan

Kazuto Okazaki