Patent GB-831263-A (GB)
Title: Improvements in or relating to the production of synthesis gas rich in hydrogen
Inventor: GRISENTHWAITE ARTHUR TURNER
IPC: C01B3/48
Filed: 1955-05-23
Abstract: <PICT:0831263/III/1> Hydrogen is produced by admixing a vaporous or gaseous hydrocarbon with steam and passing the mixture over a catalyst, e.g. of nickel, preferably at a pressure not greater than 8 atmos. absolute, to produce a gaseous mixture comprising hydrogen and carbon monoxide; cooling and compressing the gaseous mixture and admixing with further steam; passing the resulting gas in indirect heat exchange with the gas being cooled; passing the reheated gas over a catalyst, e.g. of iron oxide, preferably at a pressure of 10-30 atmos. absolute, to convert the carbon monoxide to dioxide; and removing the carbon dioxide.  The hydrocarbon may be natural gas, ethane or propane; gasoline or kerosene; or fuel oil.  As shown, hydrocarbon and steam, each at a pressure of 1-1.5 atmos. absolute, are passed via lines 1 and 2 respectively through heat-resisting steel tubes 3 containing a nickel base catalyst and surrounded by a furnace 4 from which the combustion product gases are passed to a waste heat boiler 8.  The resulting gas at a temperature of ca. 900 DEG  C. passes through a waste heat boiler 12 wherein it is cooled to 500 DEG  C., a heat exchanger 16 wherein it is cooled to 260 DEG  C., and via line 17 to a water scrubber 18 wherein it is cooled to ca. 30 DEG  C.  The cooled gas is passed via line 20 to a compressor 21 wherein it is compressed to 20 atmos. absolute, is admixed with steam at 350 p.s.i.g. via line 23 and is passed at a temperature of 180 DEG C. to heat exchanger 16 wherein the gas is heated to 380 DEG  C.  The reheated gas is passed to a carbon monoxide converter 25.  The resulting gas at a temperature of 440 DEG  C. is passed to a scrubber 27 fed with water under pressure and at a temperature of 110 DEG  C. wherein the gas is cooled to 116 DEG  C., to a further scrubber (not shown) fed with cold water under pressure and finally via line 29 to a carbon dioxide absorber (not shown). The cold water scrubber may be dispensed with when the absorber is fed with hot potassium carbonate solution.  Hot water is passed from the scrubber at a temperature of 150-165 DEG  C. and is recirculated via pump 31 and heat exchangers 32 and 33.  In order to maintain the volume of circulating water constant a portion of the water is bled off via valve 35 through a heat exchange 36 for heating feed water to the waste heat boilers. The heat exchangers 32 and 33 may be respectively in the form of the reboiler of the carbon dioxide removal plant using hot potassium carbonate or amine solution as absorbent, and the reboiler of a carbon monoxide removal plant utilizing ammoniacal copper solution as absorbent. For example, hot water at 150 DEG  C. may be passed through one reboiler containing solution boiling at ca. 120 DEG  C. wherein the water is cooled to 130 DEG  C., and then through to second wherein the water is cooled to 110 DEG  C. and the solution heated to 80 DEG  C.  The steam raised in the waste heat boilers 8 and 12 may be used in the two catalytic reactions.  Specification 831,264 is referred to.