Patent GB-779914-A (GB)
Title: Improvements in or relating to process and plant for the production of gas
IPC: C01B3/36
Filed: 1954-02-24
Abstract: 779,914. Cracking gaseous mixtures; oil gas; furnace atmospheres. LINDE, R. VON. Feb. 24, 1954 [Feb. 28, 1953], No. 5424/54. Classes 51 (2) and 55 (2). A gas, usuable as a combustion gas or as an atmosphere in heat-treatment furnaces, is produced by mixing liquid fuel with a current of gas consisting largely of non-oxidizing substances and containing a substantial amount of inert substances, then adding to the current a quantity of oxygen-containing gas sufficient only to support an exothermic but incomplete combustion, and burning the mixture. The temperature reached by the incomplete combustion must be high enough to crack the hydrocarbons and to produce water-gas reaction and to achieve this the combustion temperature is increased by admitting hot inert gases, or by preheating the fuel or combustion air. The water gas reaction is aided by the admission to the combustion chamber of catalytically acting substances, such as lithium salts or the vapours thereof. The salts may be added to the oil, e.g. as naphthenic lithium or lithium naphthenate; or they may be added as vapours of inorganic lithium salts, e.g. lithium carbonate or lithium chloride, for instance, a part of the hot inert gas fed to the burner may be passed over a trough with lithium salts. As shown, a burner 6 is supplied with liquid fuel fed at 9 into a pipe 8 and atomized by, and mixed with, steam or a portion of the product-gas admitted at 10. Products from the combustion chamber 5 pass into the pipe 8 and are added to the mixture together with air supplied through a preheating pipe 12 in heat-exchange relation with hot product gas flowing through 13. The product-gas is then sprayed with water in a cooler 15; a compressor 18 compresses it to 10-25 atmospheres and passes it, through a pipe 21 having means for removing the heat of compression, to a pressure vessel 20 for contact with cold CO 2  solvent, e.g. water, from the sprinkler 22. Water vapour also is deposited in the cooler 15. The solvent is discharged by a float valve 23, and is consequently relieved of pressure which allows the CO 2  to escape. The degasified solvent is recirculated to the sprinkler 22. The purified product gas can be stored under pressure, or the pressure can be reduced, as necessary for use, by an expansion valve 25. Alternatively, the gas may be expanded in an engine coupled to the compressor 18, and the gas, thus cooled by expansion, may be used for cooling the solvent supplied to the vessel 20. In another arrangement, the gas is expanded in an apparatus as described in Specification 405,781, [Group XIII]. In a modified layout, the compression step is omitted, the product gas being cooled by heat exchange with the CO 2  solvent which is thereby heated to release the CO 2 . The atomized fuel, the atomizing agent which is a gas or vapour delivered at high pressure at the fuel supply point, and the combustion air are mixed with a part of the CO 2 , and the mixture is burnt in the chamber 5. The product gas is additionally cooled on its way to the scrubber by heat-exchange with brine from a refrigerating machine. The fuel is aspirated from a carburetter float-chamber by an air current passing through a venturi throat, the fuel is separated from the air to form a ready-use reservoir and the air passes separately to the burner 6. The fuel is withdrawn from the said reservoir by the high-pressure atomizing agent.