GB439562A - Improvements in method of manufacturing water gas - Google Patents

Abstract

439,562. Water-gas plant. CARSON, H. J., 310, South 55th Street, Omaha, Nebraska, U.S.A. April 4, 1934, No. 10244. [Classes 55 (i) and 55 (ii)] In the manufacture of water gas, the fuel bed is progressively air blasted to incandescence at vertically spaced levels in successive zones, the lowermost air blast level being at the bottom of the fuel bed, steam being admitted above the lowermost level, the steam and air being superheated, and the ash being discharged as liquid slag which is obtained by use of a fluxing material. Flux is added to the incoming charge and to the bottom zone and combustible gas or oxygen may be added with the blasting air to keep the slag liquefied. An upper carbonizing zone is maintained, which is heated externally, and, in some cases, internally by the blast gases, part or all of the water gas being passed through the carbonizing zone. The carburetter gas outlet may be provided with a vacuum pump to reduce pressure, and draw the gases through the condenser. The gas generator 12 has a water gas zone 17 and carbonizing zone 18, and air blast inlets 20, 20<a>, 20b, and 20<c> are provided at different levels, steam being admitted at 21 above the bottom level which is maintained hot to prevent the slag solidifying. The carbonizing chamber is surrounded by an enlarged passage 22, a constricted passage 23, and an upper enlarged passage 24 leading to an outlet 25. A gas withdrawal device 26, Fig. 3, as described in Specification 439,626, is used in the carbonizing chamber and comprises a number of conical units 66 spaced to provide gas outlets 67, an adjustable cap 30 regulating the flow of gases through the fuel. An outlet 127 for steam or air is fed by a pipe 128 which extends through the carbonizing zone. A carburetter 13 has a combustion chamber 26, and oil admission pipe 27, also a heat absorbing mass 28 with an oil admission zone 29 below having oil inlets 29<a>. A lower zone of heat absorbing material 30 may be provided. The carburetter leads directly into a gas superheater 14 having a closable gas outlet 33, and a valved outlet 34 leading to a condenser 35 and vacuum pump 37. A steam superheater 15 with steam inlet 61 and outlet 62 is provided, and has outlets 42, 42<a> leading into air preheaters 16, 16<a> having air inlets 53, 53<a> and outlets 54, 54<a> to a distributing pipe 56. Two slag discharge openings 48, 48<a> are provided above the sloping hearth 47, and a pipe 49 serves for admission of gas or oxygen to maintain the bottom layer at a high temperature and keep the slag fluid, an opening 50 being used for admission of fluxing material. An outlet 51 withdraws distillation gas. In Fig. 10, a generator is shown, which is connected to two regenerative chambers, each of which is alternately heated by blow gases and used for superheating steam and preheating air. In operation, air is fed first to level 20 and as heating progresses, air is supplied to levels 20<a>, 20b, and 20<c>, and by inlet 59 to the carburetter, and inlets 58 and 57 to the steam and air preheaters, through which the hot blast gases pass to the stack 46<a>. The air blast is then cut off, and steam admitted through pipe 61 to heater 15 from which it passes by pipes 62, 63 to level 21 of the fuel bed at a temperature sufficiently high to prevent cooling of the slag. The water gas heats the fuel in the carbonizing chamber 18 externally and internally, and passes partly through outlet 51 with the distillates and partly around the carbonizing zone 18 to the carburetter 13, and downwardly to the oil admission zone 29, cracking being completed in the brickwork 30<a>, and in chamber 14 on the way to the gas outlet 33. Steam may be admitted to the carburetter through inlet 64. When lower pressure is required in the carburetter valve 33 is closed, valve 34 opened, and the vacuum pump 37 started. When the run is completed, air is passed through the preheater 16<a>, and used in heating the generator carburetter, steam superheater, and air preheater 16. In modifications, the gas superheater 14 is omitted, or each of the regenerators 16, 16<a> is used for superheating steam and preheating air chambers 14 and 15 being omitted. In Fig. 10 an additional valved gas outlet 51<a> is provided leading from the annular space 24, the carburetter and gas and steam superheaters being omitted.