Substitute natural gas

About: Substitute natural gas is a research topic. Over the lifetime, 1216 publications have been published within this topic receiving 23604 citations. The topic is also known as: synthetic natural gas.

Gasification: An Alternative to Natural Gas

Abstract: The Conference, organized by the Institution of Chemical Engineers in association with the Institute of Energy, was held at the City Conference Centre in London on 22-23 November 1995. Approximately 200 delegates attended, some 40 per cent from overseas. Presentations of papers were in six sessions over the two days covering the gasification process, air versus oxygen gasification, applications-today and tomorrow, and waste and biomass. A poster session of 12 exhibits was also on display. The prime driving force for the development of gasification is the introduction of increasingly stringent environmental standards. Papers by HMIP rang with acronyms, stoutly defending the policies of BATNEEC, BPEO and IPC. HMIP consider that there are environmentally better ways of producing electricity than from large steam turbines supplied by fossil-fired boilers. They conclude that there is a certain inevitability about gasification process development. To realize commercially viable power systems, however, it was generally agreed that close integration of gasifier and power cycle was necessary in a combined cycle format (IGCC). Several papers pointed out that investment costs of TGCC are around US%1500/kW, some 20-30 per cent higher than conventional PF plant with flue gas scrubbing, and that significant problems remain to be solved. Strong arguments were expressed in several papers in favour of oxygen-blown as opposed to air-blown gasification systems. It was also demonstrated that close integration can severely limit operating flexibility and that sophisticated control systems require developing. Demonstration plant experience was described i n papers on the Wabash River Project (Dow), Demkolec (Shell), Polk and others (Texaco). Today's applications (Sasol, Lurgi, Texaco, etc.) tended to be based on special circumstances of fuel availability and the use of chemiical by-products. A paper from EPRI described IGCC power systems as longer term options which, for developing countries with large coal reserves, may fin'd early application in co-generation and production of gas, chemicals, etc. A review of hot-gas clean-up by PowerGen concluded that this essential component of a high-efficiency IGCC power generation system had not yet been adequately demonstrated.

Tar reforming in biomass gasification gas cleaning

Abstract: Thermochemical conversion of biomass can be used to produce synthesis gas via gasification. This synthesis gas can be further upgraded to renewable fuels and chemicals provided that the gas is ultra clean. To achieve this, impurities, such as light hydrocarbons and tar compounds present in the gasification gas can be converted to syngas by reforming. The amount of tar in gasification gas can be reduced already in the gasifier by using catalytically active bed materials. Typical bed materials in fluidized bed gasification are sand, olivine, dolomite and MgO. The tar conversion activity of dolomite and MgO were found to be high at atmospheric pressure. However, the activity was lost when the pressure was increased to 10 bar. Gasification gas contains, in addition to tar, ethene, which may contribute to further tar formation in high temperature zones of the process, especially at elevated pressures. Ethene forms tar compounds by radical chain reactions. The tar formed by thermal reactions of ethene resembles the tar from high temperature fluidized bed gasification, which contains mainly secondary and tertiary tar compounds. Carbon formation on the reformer catalysts presents a challenge in biomass gasification gas cleaning. The presence of sulfur in the gas, mainly in the form of H2S, also complicates reforming. Typical catalysts used in the reformer after the gasifier are precious metal and nickel catalysts. The heat for reforming can be brought either indirectly in the case of steam reforming or by adding oxygen to the feed for autothermal reforming. Nickel and precious metal catalyst activities were analysed in experiments of around 500 hours with several different gas compositions. Catalyst deactivation was higher with steam than autothermal reforming. The use of catalytically active bed materials to reduce tar concentration already in the gasifier is especially favourable for steam reforming as the catalyst deactivation rate was decreased by the lower hydrocarbon content of the gas. Benzene, a highly stable compound, is a typical residual compound in the gas after the reformer. Thus, the reformer could be designed based on the reforming kinetics of benzene, for example in the production of synthetic natural gas. For this purpose, qualitative analysis of the effect of the main gasification gas compounds (H2, CO, CO2, H2O) on reforming kinetics were studied with a nickel catalyst. Benzene reforming can be described by first order kinetics if the parameters are estimated for the specific gas composition.; Biomassan termokemiallisella konversiolla voidaan tuottaa synteesikaasua kaasutusreitin kautta. Synteesikaasu voidaan jatkojalostaa uusiutuviksi polttoaineiksi seka kemikaaleiksi. Synteesisovelluksia varten kaasun tulee olla ultrapuhdasta. Taman saavuttamiseksi epapuhtaudet, kuten keveat hiilivedyt ja tervayhdisteet voidaan konvertoida synteesikaasuksi reformoimalla. Tervan maaraa kaasutuskaasussa voidaan vahentaa jo kaasuttimessa kayttamalla katalyyttisesti aktiivisia petimateriaaleja. Leijukerroskaasutuksessa…

Method of co-producing methanol and synthetic natural gas by coke oven gas, and plant for achieving the same

Abstract: PROBLEM TO BE SOLVED: To provide a method for co-producing methanol and synthetic natural gas by coke oven gas, and a plant for achieving the method.SOLUTION: A method for co-producing methanol and synthesis natural gas by coke oven gas includes: a step of pre-treating at least one kind of coke oven gas; a step of adding at least one kind of carbon-containing gas (CO and/or CO) to the pre-treated coke oven gas to regulate a hydrogen/carbon ratio; a step of compressing and desulfurizing the produced mixed gas and next performing methanol synthesis reaction; a step of separating the produced methanol synthesis reaction product into a high methanol flow and a low methanol flow; a step of bringing the low methanol flow into methane synthesis reaction in two or three methane synthesis reactors connected in series; and a step of separating water from the produced methane synthesis reaction product to produce synthesis natural gas.

Fossil Fuels: Examination and Prediction of Future Tends

Abstract: ............................................................................................................3 Definitions of Terms .............................................................................................4 Introduction.........................................................................................................5 Compilation of Data ...............................................................................................6 Geologic and Economic Background ...........................................................................6 Discussion and Results ..........................................................................................13 Conclusion ............................................................................................................21 Acknowledgments................................................................................................22 References ........................................................................................................22