Patent GB-353522-A (GB)
Title: Improvements in the manufacture of water gas of regulated nitrogen content
IPC: C10J3/00
Filed: 1930-04-26
Abstract: 353,522. Water gas generation. POWER GAS CORPORATION, Ltd., RAMBUSH, N. E., and BALLINGALL, J. M., Stockton-on-Tees. April 26, 1930, No. 12893 [Class 55 (i).] Water gas having a regulated nitrogen content is made by using a mixture of steam and air during the run " period, the amount of air in the air-steam mixture being regulated in accordance with the pressure, volume, or rate of flow of the gases leaving the plant. The plant may be operated automatically by hydraulic means with safety valve control devices of the kind described in Specification 282,505, [Class 55 (i), Coking &c.]. There are preferably two up runs, and one down run to every blow period, and the down run air is admitted below the coke surface. Suitable apparatus comprises a generator 1, with an air blast control valve 2, top and bottom gas outlet valves 3, 4, steam valve 6 with a three-way valve 7, and auxiliary up run and down run air valves 8, 9. Hydraulic delay valves 28 .. 31 are operated by valves 4, 3, 7, 9 respectively. A change-over valve 32, energizing valve 33 for closing down the plant, hydraulic control apparatus 35, gas washer 36, and interlocking valves 37, 38, are also provided. Manually operated isolating valves 19 .. 22 are normally kept open. The generator is airblasted in the usual way, the closed valve 4 being interlocked with the open valve 2, the control 35 then closes valve 2 and opens the steam valves 6, 7 for an up-run, the air and steam clearing out the remaining blast gases through the open stack 5, which is then closed, so that the gas generated passes through the washer 36 to storage, all as shown in the drawing. For a down-run, the pilot valve 42 closes the top gas valve 3, and opens bottom gas valve 4, and following on this, valve 9 is opened and valve 7 moved to direct the steam into the top of the generator. The delay valves ensure that steam is supplied to the top of the generator before the air so that a mixture of air and gas is prevented, the admission of the air below the fuel level assisting in this. A second up-run then takes place followed by a blow period. The interlocking system, Fig. 3, including the cylinders 34, 37, 38, comprises a compound piston 50 working in a cylinder 34 and having a wedge 55 engaging an extension of the operating rod of valve 4. Faces A, B, C have relative areas of 1, 2, 2, main 48 being at constant pressure, and main 49 at constant exhaust, so that pistons 51, 52 are pressed against the actuating lever 53, 54, and locking wedge is withdrawn when the two compartments of the cylinder 34 are on exhaust. In the drawing, the left space of chamber 34 is under pressure, and the middle space under exhaust, the auxiliary air valve 8 alone locking the bottom gas valve 4. The control of nitrogen in the gases generated is effected by control of the auxiliary air valve 25 through a relay 27 which is coupled to the gas outlet 24 by a pipe 23, or by pipes 46, 47 to either side of a differential flow meter formed by the orifice in plates 45, Fig. 2. The amount of auxiliary air is thus regulated by the pressure, or rate of flow, of the outgoing gases.