| 摘要 |
In carrying out gaseous exothermic catalytic reactions under high pressure, the temperature of the reactant gases in the catalysis chamber is controlled by circulating water in a closed circuit including heat exchangers in the chamber, the water being condensed in a part of the circuit external to said chamber, and the cooling circuit is in pressure communication with the reactant gases, means being provided for preventing water from the cooling circuit from entering the gas circuit. In the figure, which illustrates the preferred features with reference to ammonia synthesis, nitrogen and hydrogen under pressure are pumped by pump G through heat exchanger D and past catalyst masses B4, B3, B2 and B1, as indicated by the arrows, finally entering B1 at a temperature of about 400 DEG C. After passing through B1 the gases, now at above 500 DEG C., meet cooling coil C1 whereby the temperature is lowered to 450 DEG C. After further reaction and cooling in the reactor A, the gases return to a further cooler E and liquid ammonia is separated in F, the unchanged reactants being replenished from line M and recycled. Steam produced at high pressure in coils C1, C2 and C3 is condensed in a boiler I by means of which steam at a lower pressure is produced. The condensed water passes to collecting vessel V and is recirculated by means of electric motor N and pump O situated within the collecting vessel. The motor is separated from the water sump by two heat insulating baffles between which are disposed a cooling coil P and a line Q by means of which the pressure of the reactants is applied to the cooling system. The condensate returns to the sump by line R. The motor may be cooled by circulation of the reactant gases through branch S and line Q. This gas circulation may operate a fluid motor in place of the electric motor N. <PICT:0722948/III/1> |
