Ifpexol process

Fluor Solvent Process, 1198 Selexol Process, 1202 Sepasolv MPE Process, 1210 Purisol Process, 1210 Rectisol Process, 1215 Ifpexol Process, 1223 Estasolvan Process, 1224 Methylcyanoacetate Process, 1225... 

Figure 14-19. Flow diagram of Ifpexol process, consisting of IFPEX-1 and IFPEX-2 units in series. MenMdnen ami Levler, 19921...

Another example of using methanol for extraction of acidic gases is the Ifpexol process, developed and patented by the French Institute of Petroleum (Institut fran ais du petrole — IFF). Cold methanol wash is well integrated in schemes with dehydration and cold extraction of hquefied gases [280]. 

Cold methanol has proven to be an effective solvent for acid gas removal. Cold methanol is nonselective in terms of hydrogen sulfide and carbon dioxide. The carbon dioxide is released from solution easily by reduction in pressure. Steam heating is required to release the hydrogen sulfide. A cold methanol process is Hcensed by Lurgi as Rectisol and by the Institute Francaise du Petrole (IFP) as IFPEXOL. 

Ifpexol A process for removing water and acid gases from hydrocarbon gas streams by washing with a proprietary solvent at a very low temperature. Developed by the Institut Frangais du Petrole. 

Physical solvent processes give some, but not all, ofthe above qualities. The Selexol process has several industrial applications, most of them for synthesis gas deacidification and some for natural gas treatment [6-8]. A methanol-based refrigerated solvent process such as the Ifpex-2 process from the Ifpexol technology matrix ofIFP is also a good contender [9]. However, physical solvents have a high affinity for hydrocarbons and the separated acid gas stream contains large quantities of valuable hydrocarbon products. 

Figure 14-19 is a flow diagram of the combined Ifpexol concept. In the first step water is separated from the natural gas to allow low-temperature processing in the subsequent steps. This is accomplished by contacting the natural gas feed with a methanol-rich stream in a conventional countercurrent contactor. Methanol, since it is more volatile than water, is vaporized and taken overhead, while the water stream containing as little as 50 ppm of methanol is withdrawn as bottoms. Control of this column to achieve the desired splits of water and methanol while minimizing methanol losses in the water stream is critical to proper operation. 

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