Fuel for gas turbines

Tampella Power Inc. Biomass, coal LHV Fuel for gas turbines, boiler fuel 40 290-334... 

Methanol contains no sulfur and produces very little nitrogen oxide pollutants when burned, making it a very clean combustion fuel. At a power generating facility, it could be used as a supplemental fuel for gas turbines to meet peak electricity generation requirements, or it could be sold over the fence to commercial fuel and chemical companies. A commercial-scale power facility might generate 200 to 350 MW of electricity, while also producing 150 to 1000 tons per day of methanol. 

It is not the purpose of this paper to evaluate the suitability of methanol as a fuel for gas turbines. Consequently, no attention will be given to such factors as the cost of methanol fuel, safety considerations of exchanging heat between hot exhaust gases and fuel, and the dynamics of the complex cycle with recuperative chemical reactions. The purpose of this paper is to outline the thermodynamic Implications of chemical recuperation using methanol fuel as an example. 

Boucher, M. E., Chaala, A., and Roy, C., Bio-oils obtained by vacuum pyrolysis of softwood bark as a liquid fuel for gas turbines. Part I Properties of bio-oil and its blends with methanol and a pyrolytic aqueous phase. 

Boucher M.E., Chaala A. and Roy C. (2000) Bio-Oils Obtained by Vacuum Pyrolysis of Softwood Bark as a Liquid Fuel for Gas Turbines. Part I ... 

ISO 8216/2-86 - Classification. Part 2. This covers the categories of fuels for gas turbines for applications in industry and for sea engines. The Russian equivalent for this standard is GOST 28577.2-90. 

Hydrogen is an ideal fuel for gas turbines. Due to its rapid mixing with air, a smaller combustion chamber is sufficient and the efficiency is higher compared with conventional fuels. Gas turbines modified for liquid hydrogen operation yield an up to 10 % higher thermal efficiency and output compared with fossil-fueled turbines. For systems with advanced heat exchange, efficiencies of more than 50 % are estimated to be achievable. The remainder-free combustion is stable and favorable for lifetime and maintenance. Of disadvantage is NOX production. No particular difficulties are expected for a conversion of a stationary gas turbine to H2 fuel [51]. 

Fuel. Fuel for gas turbines is variable and ranges from the hydrocarbon product kerosene for jet engines to coal or natural gas for industrial gas turbines. The engineering challenges have heen to optimize fuel efficiency and to lower emissions, particularly of nitrogen oxides. 

Mixtures of H2 and CO Oxo-alcohols, reduction gas for the steel industry, fuel for gas turbines, synthetic fuels from natural gas (Fischer-Tropsdi-Synthesis Gas to Liquids GTL)... 

The polarization curve shown in Fig. 7 is of particular interest in the extension of direct carbon conversion to coal char conversion. The sample of coal was chemically cleaned by a process developed to manufacture carbon particulate fuel for gas turbines. (Ultra Clean Coal Pty. Ltd. Langley, 2004). Ash may be removed by a modified Bayer caustic digestion down to the level of 0.17%. At this level, the accumulation of ash necessary to reach 10%-volume criterion found by Weaver would require 1.5 yrs of operation at 0.1 A cm. The particulate coal (10 pm size) was charred in situ at 750°C in the presence of molten carbonate. The coal showed no tendency to agglomerate and flowed freely following pyrolysis as melt-wetted slurry. 

Source Adapted from extracts from Narula, Alternative Fuels for Gas Turbine Plants—An Engineering, Procurement, and Construction Contractor s Perspective, ASME paper 98-GT-122. 

It should be noted that because of limited LPG market, not all gas turbine suppliers are currently offering dry low NO combustors for their advanced gas turbines for this fuel. Use of moisture injection to control oxides of nitrogen can worsen thermal efficiency and increase BOP water treatment cost, especially at sites where desalination is necessary to make fresh water. Further, since it is a relatively new fuel for gas turbines, the emissions requirements with this fuel are not clearly defined by regulatory agencies. The actual emissions from the gas turbines when burning LPG are closer to those with liquid fuels than those with gaseous fuels. 

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