GB979717A - Production of acetylene - Google Patents

Abstract

<PICT:0979717/C1/1> Acetylene is produced by contacting particles of an alkali or alkaline earth metal oxide with carbon in a fluidized bed which is heated e.g. to 1500 DEG C. by radiation of heat produced from combustion of the fluidizing gases in the enclosed zone above the reactor bed by means of air added to said enclosed zone, removing the reacted mass from the upper section of the bed, cooling and reacting with water to produce acetylene. The heat required for maintaining the combustion in the zone above the bed may be supplied by heat generated externally and conducted into the zone through the wall of the reactor. The molar ratio of carbon to metal oxide may be between 3 and 10, and the fluidizing gas may be a non-oxidizing nitrogen-face gas, e.g. methane rich natural gas, naphtha, ethane or propane. Metals mentioned are barium, calcium, strontium and sodium. In the Figure the oxide reacts in fluidized bed 2 with carbon from cracked hydrocarbons fed via inlet 5 and blower 6 into the windbox 3. The bed is kept above 135 DEG C. In space 4 the H2 and CO are burned with preheated air at 375 DEG C. entering via inlet 7. The temperature is controlled by passing some combustion air to barium hydroxide drier 10 via conduit 19 from blower 9. The carbide leaves reactor 1 via overflow 11 and is cooled to 150 DEG C., in cooler 12, then conveyed to acetylene generator 13 via conduit 33. Dry hydroxide leaves via 16 and is blown to drier 10 where it is dehydrated. The oxide is separated in cylones 21 and enters reactor 1 via conduit 22. The flue gases are led to waste heat boiler 24 where they produce high pressure steam and are passed on to air heater 8. The gases then pass to scrubber 28 and are then exhausted. The reactor may be lined with 97% magnesia brick. Nitrogen and sulphur are preferably excluded from the bed.