Gas-to-liquid Technology Research Articles

ＧＴＬ（Ｇａｓ Ｔｏ Ｌｉｑｕｉｄ）技術の展望

GTL technology is one of the most promising technologies which makes it possible to convert natural gas to clean liquid fuels. They can be utilized for gasoline engine, diesel engine or fuel cell. GTL technology is composed of two or three steps: (1) Reforming of natural gas to syngas (CO+H2), (2) Conversion of syngas to liquid hydrocarbons (Fisher-Tropsch (F. T) Synthesis), or (3) Conversion of syngas to methanol and methanol to aromatics plus iso-paraffins (Methanol to Gasoline (MTG) Process).MTG process utilizes a special zeolite catalyst to convert methanol to gasoline at high temperatures, whose research octane number is about 93, and small amount of LPG. The total energy efficiency from natural gas to products is about 55%. This technology has been commercialized since 1986 in New Zealand with the scale of 15, 000 bpd.The F.T synthesis gives mainly straight chain paraffins and olefins with wide distribution of carbon number (C1_??_C100+). Products (C10_??_C20) are quite suitable material as diesel fuel, whichexhibits high cetane number (_??_70), low sulfur content (_??_0), low aromatics content (_??_0), andlow density (780g/1). These characters lead to the low emissions from diesel engine (soot, SOx, NOx and hydrocarbons).Two GTL (F. T) commercial phants have been operated since 1992 and 1993, which are developed by SASOL in South Africa and Shell in Malaysia, respectively. Lighter products (C5_??_C10) can be used as petrochemical feed stock or can be reformed to gasoline. Heavier products can be used as wax (after purification), lubricant (after isomerization) or diesel oil (after hydrocracking). Commercial GTL process has the cost competability when its scale correspond to the annual gas consumption of about 1 million ton. This means that the process can utilize the products from the gas field with rather small scale.

日本石油開発（株）のガス田開発事業

Nippon Oil Exploration Ltd. (NOEX), a subsidiary of Nippon Mitsubishi Oil Company, participates up-stream business in 11 countries with 20 oil and gas E & P projects, where NOEX has the role of operator in Malaysia, Vietnam, Australia and the United States. NOEX is involved in several gas projects in South East Asia, Australia and the United States. In general, gas field development could be commercialized on the condition that gas markets are large enough to commit long-term gas supply. Transportation method of produced gas from field sites to markets today is limited only to either pipeline or LNG tankers. These limitations restrict to make a profit in a short time, specially on these gas fields located in remote area from markets, even for bigger size of reserves. Most of NOEX gas development projects are being carried out by conventional methods, with the exception of newly discovered gas field in Australia, where early economical development is sought with the application of new technology. In this paper, five NOEX gas projects are introduced from the viewpoints of three different development types, such as pipeline, LNG and new technology.Yetagun gas field, which was discovered in 1992, offshore Andaman Sea in Myanmar, started gas production in May 2000 to export gas to Thailand through pipeline. Another gas pipeline project has been planned in Papua New Guinea to utilize oil fields' associated gas to Australian market. Gas fields in offshore Sarawak, Malaysia discovered in 1990 through 1994 are under development to feed source gas to MLNG-3 plant, which is also under construction in Bintulu, Sarawak. Planned start-up date of gas production is October 2003. Tangguh LNG project in Indonesia is also in progress, however, difficulties of finding new customers in saturated Asian gas market cause prolongation of project schedule.In May 2000, new gas reserves were discovered by drilling NOEX's exploration well Crux-1 in AC/P23 licensed area in Timor Sea, West Australia. Longer distance to the shore market and middle size of the reserves may prevent the early development of Crux gas field in case conventional approach is implemented. Application of Gas to Liquid (GTL) technology may be the most realistic alternative for Crux development under today's saturated LNG market, small domestic market and global environmental requirement. Under these circumstances, NOEX has started a feasibility study of GTL applicability to Crux gas field to make a profit as early as possible. Once GTL technology becomes viable both technically and economically, NOEX's strategy to gas resources would be changed to more aggressive direction.

00/01836 Technical and economic issues in syngas conversion in gas-to-liquids technologies

After decades of intensives development and, more recently, successful operation of three commercial-scale plants, gas-to-liquids (GTL) technology is technically ready and economically viable for large-scale commercial application. In this paper, which is based on Arthur D. Little's recent multiclient study ; we discuss the technical and economic aspects of GTL technology, and the implications for syngas production and conversion technology development efforts.

00/00085 Structure analysis of oil shale and fuel-manufacturing technology

During the past twenty years, tremendous investments from the major players in the energy market have been directed towards Gas-to-Liquid (GTL) technology. This has resulted from a significant increase in global demand of crude oil. The advantages of GTL technology in energy production are that it furnishes a broad range of environmentally clean fuels, additives and value-added chemicals that can be obtained from abundant natural resources such as natural gas, coal, or biomass. The primary commercial technology of GTL for the production of liquid hydrocarbons and value added chemicals involve the Fisher-Tropsch synthesis (FTS) process. The typical steps in the GTL process include the gasification or reforming process to obtain synthesis gas or syngas (consisting primarily of a carbon monoxide and hydrogen mixture), followed by the synthesis of hydrocarbons and oxygenates from syngas via FTS technology, and finally the upgrading of liquids hydrocarbons (known as syncrude) via hydrocracking, isomerisation, and/or hydro-isomerisation processes to produce clean kerosene, naphtha, gasoline, diesel, base oil, and value added chemicals.

ＧＴＬ（ｇａｓ‐ｔｏ‐ｌｉｑｕｉｄｓ）技術の適用性

Recently, major oil companies, engineering companies, and research-oriented venture businesses outside of Japan have claimed that the significant improvement of GTL technology has been achieved. With such technological improvement, purely commercial application of the GTL technology is being studied in several potential projects. Nevertheless, very few detailed technical and economical information has been disclosed so far. Considering the above, we have evaluated the state-of-the-art GTL technology in terms of commercial applicability with the licensor information. As a result of the economical evaluation, it is concluded that the current GTL technology can only be applied to the projects with extremely low feed gas costs and/or with existing intensive infrastructures.