Abstract: The invention relates to a method for producing a high-molecular polyester from a solidified polyester prepolymer by solid phase polycondensation. The polycondensation cleavage products of the solid phase polycondensation reaction are extracted from the product by means of a process gas, and the process gas is then cleaned and essentially recycled. According to the invention, the process gas is cleaned by means of an aqueous washing liquid. The invention also relates to an installation for carrying out the inventive method, said installation containing a crystallisation appliance (1) and a reaction appliance (2). A gas outlet (2d) of the reaction appliance (2) is directly or indirectly connected to a gas inlet (3c) in a gas cleaning system (3), and a gas outlet (3d) of the gas cleaning system (3) is connected to a gas inlet (2c) of the reaction appliance (2).
Abstract: A degassing apparatus for use with a polymerisation reactor is disclosed. Slurry from the reactor is discharged into a flask tank (3) in which monomers or dilluent vaporise to form a gas. Filler units (9, 10) are provided at the upper part of the flash tank (3). They may be selectively connected to the flash tank by valves (11, 12). No cyclone etc. is provided between the flash tank and the filter (9, 10) and these particles may then fall back into the flash tank (3). The filters may be separately isolated for cleaning or replacement.
Type:
Grant
Filed:
June 19, 2001
Date of Patent:
September 11, 2007
Assignee:
Borealis Technology Oy
Inventors:
Karin H Knudsen, Willy Wilhelmsen, Hans Narvestad, Odd J. Vardal, Ingrid S. Melaaen
Abstract: A method for efficiently removing vapor-phase contaminants from gas streams is described. A powdered adsorbent such as activated carbon is ground into a fine powder by wet grinding to form a slurry. Chemicals are added to the slurry to impregnate the sorbent to enhance sorbent effectiveness. The slurry chemical mixture is sprayed into the gas stream in the form of small droplets which evaporate to produce an aerosol of fine adsorbent particles. Vapor-phase contaminants in the gas stream adsorb onto the fine adsorbent particle surfaces and the adsorbent particles are removed from the gas stream by a conventional particle collection method.
Type:
Grant
Filed:
January 23, 2003
Date of Patent:
November 16, 2004
Assignee:
Electric Power Research Institute, Inc.
Inventors:
Ramsay Chang, Frank Meserole, Carl Richardson
Abstract: A method and apparatus for controlling or removing mercury, mercury compounds and high molecular weight organics, if present, from a resource recovery exhaust stream by separately adding a carbonaceous char to the flue gas while it is still within the unit. The char can be produced in situ by adding a carbonaceous material and allowing it to thermally decompose.
Abstract: A process for cleaning an inert gas contaminated with a metallic vapor, such as cadmium, involves withdrawing gas containing the metallic contaminant from a gas atmosphere of high purity argon; passing the gas containing the metallic contaminant to a mass transfer unit having a plurality of hot gas channels separated by a plurality of coolant gas channels; cooling the contaminated gas as it flows upward through the mass transfer unit to cause contaminated gas vapor to condense on the gas channel walls; regenerating the gas channels of the mass transfer unit; and, returning the cleaned gas to the gas atmosphere of high purity argon. The condensing of the contaminant-containing vapor occurs while suppressing contaminant particulate formation, and is promoted by providing a sufficient amount of surface area in the mass transfer unit to cause the vapor to condense and relieve supersaturation buildup such that contaminant particulates are not formed.