Plasma Technologies for Fuel Processing
Plasma Technologies of Solid Fuels Processing for Power Engineering and Metallurgy
Tech Area / Field
- NNE-FCN/Fuel Conversion/Non-Nuclear Energy
- NNE-MEC/Miscellaneous Energy Conversion/Non-Nuclear Energy
8 Project completed
Senior Project Manager
Genisaretskaya S V
Kazakh National University / Combustion Problems Institute, Kazakstan, Almaty
- Kazakh National University / Scientific Research Institute of Experimental and Theoretical Physics, Kazakstan, Almaty
- Imperial College London / Department of Mechanical Engineering, UK, London\nUniversite de Rouen / CORIA-UMR 6614 Laboratory, France, Mont Saint Aignan\nPennsylvania State University / Energy Institute/College of Earth and Mineral Sciences, USA, PA, University Park\nZarak Systems Corporation, USA, CA, Sunnyvale\nUniversity of Kentucky / Department of Mechanical Engineering, USA, KY, Lexington\nUniversity of Arizona / College of Engineering and Mines, USA, AZ, Tucson\nMyongji University / Semiconductor Technology Center, Korea, Yongin City
Project summaryThe project objective is to develop energetically effective and environmentally safe plasma technologies for the gasification and complex processing of power-generating coals, to investigate regime parameters and to find the optimal characteristics of these technologies in energy, metallurgy and other industries.
The objective of the project is stipulated by the problem of more and more low-grade power coal involving into industry, by necessity of deficit and expensive liquid and gaseous fuels using in heat-and-power engineering, metallurgy and other branches of industry and by ecological deterioration of environment. It is well known that during low-grade coal burning their ignition and burning-out is becoming worse and harmful dust and gaseous emissions (ash, nitrogen and sulphur oxides) are increased.
In heat-and-power engineering black oil and natural gas are used for low-grade coal ignition and flame stabilisation, but it does not solve the problem. Their co-combustion with coal decreases the main indexes of Thermal Power Plants (TPP) (boilers’ efficiency decreases, dust and gaseous pollutant emissions increase, high temperature corrosion of boiler’s heating surface increases, etc.).
According to the study the method of plasma gasification and complex processing of low-grade solid fuels, suggested in the project, is the most perspective. Its idea is to heat coal powder by electroarc plasma, which is an oxidant, to the temperature of complete gasification at which organic mass of coal is transferred into ecology pure fuel. It is synthesis gas free from ash particles, nitrogen and sulphur oxides. Simultaneously the recovery of Coal Mineral Mass (CMM) and production of valuable components, such as technical silicon, ferrosilicon, alumina and carbosilicon, including rare microelements: uranium, molybdenum, vanadium et al. takes place. According to the estimations of Institute of Economy and Manufacturing Management of RAS Siberian Branch in Novosibirsk, the market cost of gaseous and condensed products, obtained as a result of coal plasma thermochemical processing, is ten times higher the cost of coal and the equipment for its processing.
The first step in realisation of this technical solution is a method of electrothermochemical preparation of coal to burning workable by authors. The development of this method is in good progress now. In this method coal dust flow sent to boiler furnace is pided in two parts. One part is heated by electroarc plasma to the temperature of near complete volatile coal emission and partial gasification of the coke residue. It is done to provide total emission of fuel gases to be at the same volatile level of the content in high-grade coals, which are able to ignite and burn without stabilisation by black oil (mazut) or natural gas. Thus high-reactive two-component fuel (fuel gas + coke residue) is obtained from the part of air-fuel mixture that passes through the arc zone. It can be ignited during mixing with the residual part of the air-fuel mixture and thus stabilise the combustion process. This method is successfully used in a number of TPPs in Kazakhstan, Russia, Ukraine, Mongolia, China, Korea and Slovakia.
However further wide inculcation of this method is restrained by absence of advanced calculation methods of work process of boilers equipped by burners with plasmatrons. When plasmatron is used output parameters of plasma-coal burner are greatly different from ones of existed coal-dust burners. Fuel mixture reacting flame enters a boiler, and this can cause changes of the main parameters of combustion process. As a consequence, complex investigation of boiler work process with consideration of plasma technology becomes especially significant. It should combine computer simulation of the processes proceeding both in plasma-coal burner and boiler space, with experiments in laboratory and industrial conditions. Carrying out of such investigation will allow predicting the main parameters of the process in boiler’s space with burners equipped with plasmotrons. It is necessary for the designing of new and optimisation of existing boiler units during their modernisation.
The scope of project works is related to applied investigations. As a result, highly effective technology of low-grade power coal plasma gasification and complex processing will be created. Operating parameters will be investigated and optimal characteristics of this technology use in power, metallurgy and other branches of industry will be found.
Project realisation will allow to decrease consumption of deficit and expensive fluid and gaseous fuel in power engineering and other branches of industry; to improve essentially coal burning plants environment due to minimisation of harmful dust and gas emissions; to create highly effective environmentally appropriate technology of plasma gasification and complex processing of low-grade solid fuels with valuable components extracted from coals mineral mass.
During fulfilment of the project it is suggested to realise the following tasks:
– To carry out thermodynamic analysis of multicomponent heterogeneous systems (coal + oxidant) with the help of universal program for thermodynamic calculations TERRA.
– To make experimental stand and units for experimental investigation of plasma heating, gasification, complex thermochemical processing of solid dust fuels.
– To fulfil experimental researches of plasma heating and thermochemical processing of pulverised solid fuels.
– To investigate end-product formation along plasmachemical reactor axis, chemical and X-ray analysis of initial condensed phase.
– To develop kinetic mathematical model of moving, high-temperature heating and thermochemical transformations of coal dust fuel at oxidant flow in cylindrical duct with internal plasma source.
– To fulfil kinetic, thermal and dynamic analysis with the help of mathematical model of moving, high-temperature heating and thermochemical transformations of coal dust fuel at oxidant flow. For research of the processes running at chamber for electrothermochemical preparation of fuel to burning, it is supposed to use stage method of calculation, which is under developing now.
– To compare experimental and computed data and to correct the models if it is necessary. To issue technological recommendations for power coals thermochemical plasma processing realisation in heat-and-power engineering and metallurgy.
As a result of project fulfilment the following ISTC objectives will be realised:
– High skilled scientists specialised in the field of material plasma treatment, as well as scientific potential of specialists connected to weapon development with subsequent their reorientation into advanced technologies of civilian branches of industry (power engineering and metallurgy) will be involved;
– Project realisation will stimulate integration of Kazakhstan scientists into scientific world community. It is supposed to participate in International scientific and technical conferences with publications of the main project results for expansion of field of plasma technology applications and their marketing.
– Researches by the project will be of applied nature. They will assist to use of plasma technologies in peaceful goals and especially in the field of environment protection and produce of power and new energy carriers. Also these researches will have self-independent scientific importance for fundamental science in the field of plasmachemistry, chemistry of solid fuels, thermal physics, ecology and plasma technique.
– Project implementation will contribute greatly to solving national and international technical problems concerned with replacement of expensive and deficit gaseous and liquid fuels from coal burned power engineering and coke from metallurgy with simultaneous improving of ecology-economical indexes of metallurgy and power plants. Moreover, as a result of plasma thermochemical processing of low-grade solid fuels synthesis gas for methanol manufacture will be obtained. Traditionally methanol is made from natural gas and high-potential gaseous reductant instead of coke. Thanks to getting valuable components from mineral part of coals, such as technical silicon, ferrosilicon, alumina, carbosilicon, uranium, molybdenum, vanadium et al., the source of raw materials for metal mining, chemical, metallurgy industries and nuclear power engineering will be enlarged.
– Developed plasma technologies have novelty and competitive ability. They will promote transition to market-based economics in civil industries. At the moment proposed for developing technology is unique and has no analogue.