GB1530314A - Fluid-wall reactors and their utilization in high temperature chemical reaction processes - Google Patents

Abstract

1530314 Fluid wall reactors THAGARD TECHNOLOGY CO 6 Oct 1975 40886/75 Headings BIF and B1X [Also in Divisions Cl C7 and F4] Chemical reactions at elevated temperature are carried out by causing radiation to be incident on one or more reactants in a reaction zone defined by a wall of fluid transparent to that radiation, the wall of fluid being located within a heat shield of refractory material which reflects radiation, sufficient radiant energy being absorbed in the reaction zone to raise the temperature of the or at least one reactant to sustain the reaction. If necessary a target material may be introduced to absorb the radiation and transfer energy to the reactants. Additional initial heating means may be provided within the reactor tube. In the embodiment of Figs. 1A and 1B a porous reaction tube 61 having an inlet end 62 and outlet end 63 is contained within a cooled pressure vessel 70 forming a plenum 85 into which fluid is admitted at 83 and passes through the porous walls of the reaction tube to form a protective blanket for the inner wall thereof. Electric heating elements 101 a-c heat the reactor tube so that it emits radiation. A heat shield 120 is provided within the plenum. Reactants are introduced in a gaseous stream at 91 through a diffuser 95. Solid reactants or target material are introduced at 121. Cooling means may be provided at the exit end. A broadly similar but more elaborate structure (Figs. 6A to 14, not shown) comprises one or more fog-forming nozzles for introducing the reactants; the reactor tube is coupled to the pressure vessel at the top via bellows and is held in tension by a weight and pulley system; means are provided for coating the surfaces of the reactor tube, heating elements and heat shield with a refractory oxide prior to use as an anticorrosive coating and for decreasing or increasing the pore size of the reactor walls during reaction by deposition of carbonaceous material or etching respectively, said means comprising means for feeding suitable reactants to the reactor. Automatic control means are also described. A variable temperature profile heat exchanger (Fig. 12, not shown) for cooling exit gases comprises a pair of refractory walls having a spiral refractory baffle between to define a spiral, annular coolant channel, the coolant after passing through the channel may be discharged into the plenum of the reactor proper. The apparatus may be used for pyrolysis of hydrocarbons and hydrocarbonaceous materials to form carbon black; dissociation or reduction of salts or oxides to metals; production of carbon or talc particles coated with silicon carbide to form an abrasive; incineration of waste; formation of aluminium carbide; formation of carbon disulphide from hydrogen sulphide and methane; conversion of organic waste to fuel gas (see Groups C4-5, C6-7, F3-4).