Distillation Patents (Class 62/643)
  • Patent number: 5653126
    Abstract: A packing material capable of improving the uniformity of liquid distribution and of achieving a preferable gas-liquid contact reaction, even in the case where the specific surface area of the packing material is small, includes a plurality of projections provided on the surface of a thin plate, and a plurality of holes provided respectively between the projections. In one embodiment, the transfer extension of each projection is larger than a longitudinal extension thereof, so that descending liquid flows downward while being transversely dispersed by the projection. The holes are provided between the projections so that they do not obstruct the transfer dispersion of liquid at the projection. Moreover, the holes accelerate the transverse dispersion of liquid, or the dispersion of liquid between front and rear surfaces of the thin plate, by the surface tension of the liquid. As a result, excellent uniformity of liquid distribution can be obtained on the surface of the thin plate.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: August 5, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Susumu Harada, Satihiro Yoshimatsu, Kazuo Someya, Naruyasu Okamoto
  • Patent number: 5649433
    Abstract: An improved cryogenic liquefied gas container, or a so-called cold evaporator (CE) for containing a plurality of different liquefied gases such as oxygen and nitrogen gases can be installed on a site with a limited surface area and can store the gases at a substantially equal and constant temperature level to ensure a stable gas supply to consumers that may include medical facilities and manufacturing plants. A plurality of inner tanks 4 are vertically arranged and surrounded by an insulation layer 3 in an outer shell 2 in order to economically utilize the site. The temperature of the high boiling point liquefied gas LG1 contained in the upper inner tank 4a and hence the internal pressure of the upper inner tank are stabilized by means of a heat exchanger section 11 to which the low boiling point liquefied gas LG.sub.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: July 22, 1997
    Assignee: Daido Hoxan Inc.
    Inventors: Hiroaki Suzuki, Yuji Morimoto, Yasuo Tanaka, Taturu Yamauchi
  • Patent number: 5638699
    Abstract: A high purity nitrogen gas generator is provided which can be rapidly returned to a stable state when boil-off gas is generated in a liquid nitrogen storage tank 10. The high purity nitrogen gas generator includes a liquid nitrogen storage tank 10, a rectification column 7, a liquid nitrogen introduction pipe P15 for supplying liquid nitrogen from the liquid nitrogen storage tank to the rectification column, an inverted U-type pipe P13 whose upper end is positioned at a height in the vicinity of the top portion of said liquid nitrogen storage tank connected to the bottom portion of said liquid nitrogen storage tank 10, said liquid nitrogen storage tank 10 and said liquid nitrogen introduction pipe P15 being connected with each other by way of said inverted U-type pipe, the upper end of the inverted U-type pipe and the top portion of said liquid nitrogen storage tank are connected with each other by means of a pipe P17 and a control valve V3 provided on the way of said pipe P17.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: June 17, 1997
    Assignee: Teisan Kabushiki Kaisha
    Inventors: Takao Yamamoto, Shingo Koizumi
  • Patent number: 5617742
    Abstract: A distillation apparatus having applicability to an air separation plant in which a distillation column is suspended within a containment sleeve from a main heat exchanger or a head condenser of the distillation column. The suspension of the distillation column is flexible so that the distillation column can assume a vertical orientation under influence of gravitational force to be self-leveling.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: April 8, 1997
    Assignee: The BOC Group, Inc.
    Inventor: Karl O. Toppel
  • Patent number: 5613374
    Abstract: In the process for the low temperature separation of air, purified and cooled air is fed into a distillation system comprising at least one rectification column and there is rectified by a counter-current material exchange between a vapor and a liquid phase. The material exchange in at least one section in at least one rectification column is brought about by a packing having a specific surface area of at least 1000 m.sup.2 /m.sup.3.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: March 25, 1997
    Assignee: Linde Aktiengesellschaft
    Inventors: Wilhelm Rohde, Anton Moll
  • Patent number: 5590543
    Abstract: The present invention relates to an improvement to cryogenic air separation processes which produce an ultra-high purity oxygen product and nitrogen and/or commercial purity oxygen products. In particular, the improvement of the present invention is characterized by removing a portion of liquid descending the distillation column system from the distillation section proximate to the location for withdrawing the oxygen-containing side-draw stream.
    Type: Grant
    Filed: August 29, 1995
    Date of Patent: January 7, 1997
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Rakesh Agrawal, Donn M. Herron, Thomas R. White
  • Patent number: 5582032
    Abstract: A process for producing an ultra-high purity fluid product comprising the steps of collecting in the lower portion of a cryogenic fractionation zone an ultra-high purity fluid product; providing reboil to said fractionation zone by condensing a portion of a lesser purity composition of the same fluid product by indirect heat exchange in a first reboiler; and vaporizing said portion of said lesser purity composition by indirect heat exchange with a warmer stream of an impure fluid.
    Type: Grant
    Filed: August 11, 1995
    Date of Patent: December 10, 1996
    Assignee: Liquid Air Engineering Corporation
    Inventors: James T. Shelton, deceased, Bao Ha
  • Patent number: 5582033
    Abstract: A cryogenic rectification system for producing nitrogen having a low argon content wherein the reflux ratio in the upper portion of the higher pressure column of a double column system is modified by withdrawing nitrogen vapor from below the top of the column, liquefying the withdrawn vapor, and returning the liquefied nitrogen to the column at or near the withdrawal point and below the top of the column.
    Type: Grant
    Filed: March 21, 1996
    Date of Patent: December 10, 1996
    Assignee: Praxair Technology, Inc.
    Inventors: Dante P. Bonaquist, Michael Y. Jin
  • Patent number: 5546765
    Abstract: An air separating unit which can jointly produce high purity nitrogen gas and compressed dry air of high quality freed of hydrocarbons such as methane and ethane. The air separating unit is constructed such that compressed dry air freed of hydrogen, carbon monoxide, carbon dioxide and moisture is cooled down near to its liquefying point and introduced into a rectification column (30) and nitrogen gas separated by rectification from the compressed dry air in this rectification column (30) is taken out as a product. The rectifying portion in the rectification column (30) is divided into a lower rectifying portion (34) and an upper rectifying portion (36), and in this lower rectifying portion (34), hydrocarbons such as methane are mainly removed from the compressed dry air, and the compressed dry air which has passed through the lower rectifying portion (34) is taken out as a product.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: August 20, 1996
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Takashi Nagamura, Shinji Tomita
  • Patent number: 5537840
    Abstract: A downflow heat exchanger, particularly applicable as the main condenser/reboiler of a double column cryogenic air separation plant, wherein liquid distribution for uniform flow is carried out above the vapor passages and the well distributed liquid is passed into the liquid passages, preferably angularly onto the bridge fins, and then down through the liquid passages cocurrently with vapor in adjacent vapor passages.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: July 23, 1996
    Assignee: Praxair Technology, Inc.
    Inventors: Vijayaraghavan Srinivasan, Michael J. Lockett, John H. Ziemer