Patent GB-787829-A (GB)
Title: Process for producing valuable gaseous hydrocarbons
IPC: C10G9/36
Filed: 1956-05-02
Abstract: 787,829. Gas manufacture. KOPPERS GES., H. May 2, 1956 [May 2, 1955; Nov. 23, 1955], No. 13583/56. Class 55 (2). Hydrocarbon oil or gas is cracked, to produce a hydrocarbon gas, by introducing it into a high velocity stream of hot carrier gas, the mixture being directed into a reaction chamber which is so enlarged in comparison with the section of the mixing zone that the reaction proceeds without contact with the walls of the chamber which may be water-cooled to produce a sudden drop in temperature of the products of the reaction and thus to prevent the formation and deposition of elementary carbon. In Fig. 1, a regenerator 20 is heated by fuel and air or oxygen supplied by a nozzle 21, the combustion products passing to the stack 24. When the regenerator is sufficiently heated, the valve 22 is closed and a carrier gas, e.g. steam or combustion products, is admitted at 26 and is passed upwardly through the regenerator 20, through the passage 17 into the chamber 16 becoming heated to about 1200‹ C. The mixing zone comprises a venturi throat, which may be water-cooled, between the chambers 16, 1, the oil being injected into the throat through apertures opening under a shoulder in the throat. The product gases from the reaction chamber 1 pass, at a temperature below 450- 500‹ C., to an indirect cooler 32, the coolant preferably being steam admitted at 33 and exhausted at 34. The gases then pass through an electrostatic precipitator 37 and booster 39 to a place of use. To ensure that the residual oil for the precipitator is pumpable, a diluent hydrocarbon oil of higher boiling point is sprayed into the precipitator. The residues from the cooler 32 and the precipitator 37 are conducted by a pipe 41 to a tank 29, and to facilitate discharge of residual oil from the cooler 32, a small quantity of hydrocarbon oil may be admitted at 35. Residual oil from the reaction chamber 1 is taken to the tank 29 by a pipe 28, a pump 42 supplying the nozzle 21 from the tank. The gas produced in the chamber 1 may be diluted by a gas, with a high carbon monoxide and hydrogen content, produced by an exothermic reaction device 46 supplied with oil at 44 and with oxygen or air at 47. Instead of steam alone, a mixture of steam and product gas, or other hydrocarbon gas, may be supplied to the regenerator 20. The apparatus may comprise two regenerators and two reaction chambers working in alternation. In a modified lay-out, the product gas from the reaction chamber 1 passes directly, at a temperature of about 700‹ C., into a receiver in which it is cooled and washed with water, the mixture of gas and water spray and vapour passing to another vessel in which further water is injected to cool the gas to about 200-250‹ C. The scrubbed gas passes to an electrostatic precipitator and from thence through an indirect cooler to storage. The water and condensate mixture from the scrubbers, and the residual oil from the indirect cooler pass to a settling tank, the oil flowing through a top-level outlet pipe to the main oil tank from which it is pumped, with fresh make-up oil, to the venturi mixing zone of the chamber 1. The water is drained from a lower-level outlet pipe for re-circulation, with make-up water, to the scrubbers. The product gas, because of the scrubbing, contains water vapour, and some of the product gas, being passed back to the regenerator 20 to act as a carrier gas instead of steam, is reacted in the regenerator to form water gas which is enriched with oil gas in the chamber 1. The residual oils from the precipitator are pumped, with make-up oil, to the burner 21 of the regenerator 20.