| 摘要 |
Fuel gas is produced by hydrogasifying a liquid hydrocarbon at 1250-1400 DEG F., using as source of hydrogen the gas mixture produced by catalytic steam reforming of the same liquid hydrocarbon (said mixture comprising H2, CO, CO2, CH4). In a particular embodiment, naphtha, for example, and the hydrogen-containing product of steam reforming of naphtha are pre-heated to 1400 DEG F., by combustion of recycled reformer naphtha and passed at 375 p.s.i.g. into a hydrogasifier. Steam is present or absent depending on whether excess in the reformer product has been removed. Exothermic hydrogasification occurs and the gaseous products are cooled by heat exchange with reformer naphtha (for recycle to the reformer) with steam (which is superheated to 448 DEG F. and 400 p.s.i.g. and supplied to the shift converted following the reformer) with water (for superheating as above) and with fat oil, to a final temperature of 100 DEG F. The gaseous products are C1-C5 hydrocarbons, benzene, and toluene and have a heating value about 800 B.Th.U./ft.3 The aromatics are removed by countercurrent exchange with lean oil, which is then stripped and recycled, and the light hydrocarbons are withdrawn as product. (1) Simultaneously, naphtha is heated to 750 DEG F. by exchange with gaseous reformer product, mixed with steam (vaporized and superheated by the heat of the gaseous reformer products) and passed at 350 p.s.i.g. into the catalytic reformer. A gas mixture containing CH4, CO, CO2 and H2 at 1400 DEG F. and 300 p.s.i.g. is formed, cooled to 1215 DEG F. by heat exchange with the feed, and introduced with steam (at 448 DEG F., 400 p.s.i.g. as previously disclosed) into a shift converter wherein the CO content is reduced below 1.5% by volume. Some reformer product, sidestepping the converter, is cooled and recovered per se. (2) The shift converter effluent after cooling is stripped of steam and either recycled to the hydrogasifier preheat furnace as the hydrogen-containing gas or withdrawn itself as product. (3) Flue gases from the reformer superheat steam for recycle and after further cooling, are released. The products (1), (2), (3) may be blended in any proportion to give a fuel gas with the required heating characteristics. The feedstock is desulphurized before use in the process, for example as described in Specification 902,148. |
