Hitachi, Ltd.

Sachihiro Yoshimatsu

Norio Nakazato

Norihide Saho

Makoto Nawata

Susumu Harada

Takeo Nemoto

Hidekazu Nakamoto

Chikao Oda

Youichi Itou

Takatoshi Kinoshita

Kengo Sugiyama

Yasuo Tasaka

Shintaro Sado

Hirohiko Shindoh

Michimasa Okabe

Sadao Masuda

Kazuo Ishida

Tadashi Takada

A compressor unit in which the oil separated by a plurality of oil separators to a gas suction side pipe of the previous stage oil separator which contains gas whose oil concentration is higher than that of the gas from which oil has been separated, with the separated oil being returned to a compressor. The plurality of separators enables a simplification of the arrangement of the oil returning pipe, a prevention in a reduction in the discharge flow rate of the compressor, and reduction in space required for the separators.

Compressor unit and separator therefor

The present invention comprises a pair of agitator blades which have a plurality of annular members connected to each other and which are provided in parallel in a cylindrical vessel body, the agitator blades being held so that the edges of one of the agitator blades enter the rotational region of the other agitator blade and pass therethrough. Consequently, the invention prevents liquid to be treated from adhering to and rotating together with rotational shafts and the agitator blades and deterioration in product quality due to scaling so as to enable the continuous treatment of a highly viscous material.

Continuous treatment apparatus for viscous material

This invention relates to an air separation method and apparatus for liquefying and separating feed air into oxygen and nitrogen by use of a single rectification column. The temperature of the feed air, which is liquefied, is reduced to the temperature necessary for the condensation and liquefaction of pure vaporous nitrogen inside the single rectification column and is used to condense and liquefy the pure vaporous nitrogen and vaporize the feed air. After the pressure of the feed air thus vaporized is raised to the pressure necessary for the condensation and liquefaction of the pure vaporous nitrogen inside the single rectification column, the vaporized feed air is introduced into the single rectification column so that pure gaseous nitrogen can be withdrawn from the top of the single rectification column, pure gaseous oxygen from a lower portion of the column and waste gas rich in nitrogen from an intermediate portion of the column. Thus, the present invention makes it possible to carry out air separation with a high rate of recovery of oxygen using a single rectification column.

Air separation method and apparatus therefor

A temperature control method for a reversing type heat exchanger group wherein an outlet temperature of reheating gas of an arbitrarily selected reversing type heat exchanger which serves as a reference in the reversing heat exchanger group is rendered equal in value to a reference control temperature set beforehand in such a manner so as to satisfy the sweeping temperature difference. The outlet temperatures of the reheating gas in the other reversing type heat exchangers of the reversing type heat exchanger group are rendered equal in value to the outlet temperature of the reheating gas in the reversing type heat exchanger serving as the reference. Thus, the temperature of the cold end of all of the reversing type heat exchangers of the reversing type heat exchanger group are caused to be balanced equally whereby ice and dry ice deposited on the feed water channels can be effectively removed by a sweeping action.

Temperature control method for reversing type heat exchanger group of

In a process of and a system for liquefying air to separate its components employing a so-called compound fractionating column, the system includes a fractionating medium pressure column into which a part of feed air is introduced to flow therethrough as an upwardly flowing gas for contact with a returning liquid, so as to obtain nitrogen gas at the top thereof and change the returning liquid to liquefied air as it reaches the bottom thereof, a first condenser adapted for a heat exchange between a liquefied air of a reduced pressure, which has been obtained by allowing an expansion of the liquefied air available at the bottom of the medium pressure column, and the nitrogen gas obtained at the top of the medium pressure column, so as to liquefy the nitrogen gas to make use of it as the returning liquid for the medium pressure column, a second condenser adapted for a heat exchange between the remainder part of feed air and liquefied oxygen to evaporate the oxygen, and a fractionating low pressure column through which the evaporated oxygen is made to flow as an upwardly flowing gas adapted to be contacted by a returning liquid coming down from the top of the low pressure column for a fractionation, whereby an impure gas is obtained at the top of the low pressure column, while the returning liquid is changed to liquefied oxygen as it reaches the bottom of the low pressure column.

Process of and system for liquefying air to separate its component

Growing community of inventors

Kudamatsu, Japan

Sachihiro Yoshimatsu