Real-Time Production of Synthetic Gasoline, Kerosene or Diesel from Methane in the Flare Stream Associated Gas in Nigeria

Abstract

Any gas can be liquefied at atmospheric pressure if it is cooled sufficiently. Fundamentally, every gas has its critical temperature, above which it cannot be liquefied by increase of pressure, but if it is cooled below its critical temperature, it liquefies if pressure is gradually increased e.g. the critical temperature for oxygen (-181.1 oF or -119 oC), nitrogen (-232.4 oF or -147 oC), hydrogen (-399.8 oF or -240 oC), methane (-116.63 oF or -82.3 oC) et cetera. On the other hand, any gas which has a critical temperature above room temperature can be liquefied by pressure alone e.g. ammonia (270.3 oF or 132.4 oC), chlorine (291 oF or 144.0 oC), carbon dioxide (87.9 oF or 31.1 oC), hydrogen chloride (124.5 oF or 51.4 oC), hydrogen sulfide (212.7 oF or 100.4 oC) and hydrogen dioxide (315.5 oF or 157.5 oC). This study on the real-time (direct/single-step) production of synthetic gasoline, kerosene or diesel from methane in the flare stream associated gas in Nigeria, stated the various sources of methane, the hydrocarbon components of gasoline, kerosene and diesel, the five practical ways of transporting methane (natural gas) to consumer (i.e. by pipeline, CNG, LNG, NGH and GTL) and explained the relation of liquids to gases and solids.

Theoretically the investigation reviewed the concept of gas liquefaction from the fundamental gas laws and their application in various processes (mechanical refrigeration, turbo-expander cycle, joule-thomson cycle and fischer-tropsch 'FT') as well as distinguished between the various types of catalysts, their mechanism of catalytic reactions (homogeneous and heterogeneous) and their ability to generate radicals/ hydrocarbon building blocks. Also, the paper reviewed the chemical reaction mechanism of the existing indirect/direct GTL models and subsequently proposed four single-step GTL processes based on the synergy/synthesis (i.e. combined application or effects) of various scientific fundamentals, including the direct chemical conversion of CNG/LNG to GTL.

The study estimates that 1,570.7500 barrels (8,819.483 cu. ft.) equivalent to 65,971.5 gallons or 251,320 liters of synfuel products plus 11.5 MW electricity could be obtainable daily from a 20 MMscfd flare line made up of 78.5375% methane.