- Email: [email protected]
Research on high speed diesel engine using with UCMCWF
7 1 Process heating, power and incineration
(energy applications
in industry)
temperature is well below the turbine inlet temperature of the current gas turbines, a topping gas turbine cycle has been proposed that can enhance the cycle efficiency of the conventional PFBC plants. In the topping cycle a recuperated gas turbine fuelled with natural gas utilizes the coal combustion heat to preheat the compressed air before the gas turbine combustor. An influence of such an ‘external heat recuperation’ on efficiency, power and total fuel costs for various proportions of used coal and natural gas in the proposed advanced PFBC plant has been analysed. 02/02180 Repair welding of cracked steam turbine blades using austenitic and martensitic stainless-steel consumables Bhaduri, A. K. e/ crl. Nuclear Engineering and Design, 2001, 206, (2-3), 249-259.
The procedure for repair welding of cracked steam turbine blades made of martensitic stainless steel has been developed using the gas tungsten arc welding process. Weld procedures were developed using both ER 316L austenitic and ER 410 martensitic stainless-steel filler wire. The overall development of the repair welding procedure included selection of welding consumables (for austenitic filler metal), optimization of post-weld heat treatment parameters, selection of suitable method for local pre-heating and post-weld heat treatment (PWHT) of the blades, determination of mechanical properties of weldments in as-welded and PWHT conditions, and microstructural examination. After various trials using different procedures, the procedure of local PWHT (and preheating when using martensitic stainless-steel filler wire) using electrical resistance heating on the top surface of the weldment and monitoring the temperature by placing a thermocouple at the bottom of the weld was found to give the most satisfactory results. These procedures have been developed and/or applied for repair welding of cracked blades in steam turbines. ;2&?‘l’lF
Research
on high speed diesel engine
using with
Zhang,
W. CI crl. Procerdings - Annrrul Inlernationul Pittsburgh Conference, 2000, (I 7). 736-744. nations have had grave concerns h recent years, oil importing
Cnal
about the security of oil supply and price volatility in the OPEC dominated market place and are seeking to reduce their dependence on oil. Ultra clean micronized coal water fuel (UCMCWF) are emerging as the leading alternative to oil and their use is being aggressively pursed in China, Italy and Japan. In China there are millions of diesel engines working in agricultural fields and small power stations. In laboratories using UCMCWF as an alternative oil fuel have been made using Datong coal with coal containing less than 1% ash, viscosity less than 500 mPa s and concentration between 50% and 6096, used UCMCWF in high speed diesel engine have been tested successfully. The testing result indicated that UCMCWF can well work in small high speed diesel engines when modifying nozzle and oil pump system of diesel engines. 02/02182 Second-generation WSOlG gas turbine Robertson, A. er al. Proceedings Nuidixd
Bed Cnmhusrion,
200
PFB plant performance of I/W Inrernational
1, (I 6),
1338-l
with
Conference
on
344.
Research is being conducted under United States Department of Energy Contract DE-AC21-86MC21023 to develop a new type of coalfired plant for electric power generation. A second-generation or advanced pressurized circulating fluidized bed combustion (APCFB) plant promises efficiencies greater than 46%, with emissions and cost of electricity significantly lower than those of conventional pulverizedcoal-fired plants with scrubbers. The APCFB plant incorporates partial gasification of coal in a carbonizer, combustion of carbonizer char in a pressurized circulating fluidized bed combustor (PCFB), and combustion of carbonizer syngas in a topping combustor to achieve gas turbine inlet temperatures of 2300°F and higher. After completing pilot plant tests of a carbonizer, a PCFB, and a gas turbine topping combustor, all developed for this new plant, a higher heating value efficiency of 46.2% was calculated for the plant. In that analysis, the plant operated with a Siemens Westinghouse 501F gas turbine and a conventional 2400 psig steam cycle with 1000°F superheat and reheat steam and a 21-m. mercury condenser back pressure. This paper identifies the efficiency gains that this plant will achieve by using a more advanced Siemens Westinghouse W507 G gas turbine together with superheat and reheat steam temperatures increased to 1050°F. 02102183 The gas turbine in a power plant with pressurized circulating fluidized-bed combustion Stuhlmueller, F. el al. Proceedings of the Intrrnutionol Conference on Fluidixd Bed Combustion, 2001, (16), 1357-1370. The objective of introducing the circulating variant of pressurized fluidized bed combustion is coupled with the intention to simultaneously implement this technology with standard gas turbines designed for combusting high-grade fuels such as natural gas and 282
Fuel and Energy Abstracts
July 2002
distillate fuel oil. This presentation uses the commercially marketed Siemens gas turbines to illustrate the associated requirements imposed on the coal conversion system and hot gas cleanup as well as necessary modifications to the gas turbine. The report focuses on both power plants equipped with conventional circulating pressurized fluidized bed combustion (1st generation PCFB) and those with partial coal gasification (2nd generation PCFB).
11
PROCESS HEATING, POWER AND INCINERATION Energy
applications
in industry
02/02184 A coal-firing oil heating furnace Tang, M. PCT Int. Appl. WO 01 86,214 (Cl. F24H1/28), 15 Nov 2001, CN Appl. 2,000,227,722, 31 Mar 2000. 21. (In Chinese) A coal-firing oil heating furnace, where its hearth is in the furnace shell, and the intracavity of the hearth is separated from the intracavity of the furnace shell. The lower ends of the fire-tubes are communicated with the hearth, and the upper ends of the fire-tubes are communicated with the flue. There is an oil jacket containing the heat-transferring oil between the outer surface of the hearth and the inner surface of the furnace shell. The jacket is divided into several units by baffle plates, and the heat-transferring oil is forced circulating through each unit by an inner circulating pump, further an outer circulating pump is used to send the heat-transferring oil to the service position and takes it back. The invention can reduce the heating cost of the heat-transferring oil greatly and can avoid carbonization or coking. The invention can be applied to the circulating and heating of the heat-transferring oil in the industry of rubber, shoes material, textiles, dye printing, chemical engineering. An extended version of the countercurrent back02/02185 mixing model suitable for solid mixing in two dimensional fluidized beds Abanades, J. C. and Grass, G. Recrnrs Prog. Genie Procede.s. 2000, 14, (76), 551-558. A new mathematical model to describe axial and lateral mixing in fluidized beds is presented. The model is an extension of previous versions of the countercurrent backmixing model that were restricted to axial mixing only. The fluidized bed is divided in parallel ‘mixing columns’, that are convective currents induced by the bubbles. Each mixing column has a central upflowing stream of solids and two adjacent moving downwards. The practical application of the model requires a minimum knowledge of the bubble properties and the definition of one empirical parameter: the exchange coefficient between counter-current phase, Kw, The model can be rapidly solved with the proposed algorithm and reproduces semi-quant, the main features observed in mixing experiments carried out in a bidimensional fluidized bed of coal and PVC as tracer. 02/02186 Benefits of one-dimensional simulation of fluidized bed systems Hiller, R. and Faulhaber, S. Proc. Anrrtr. Inr. Pirrshurgh Coal Conf., 2000, (17), 2059-2078. Two examples of a fluidized bed system are presented to point out the possibilities and limits of the onedimensional and three-dimensional modelling A model developed by Fraunhofer UMSICHT was used for the one-dimensional simulation, the three-dimensional modelling was based on a CFD code. The onedimensional simulation tool is able to predict the operating behaviour of a bubbling tluidized bed combustor, circulating fluidized bed combustor as well as gasifiers. The following features are integrated: fluid dynamics of the gas phase and the solid matter particle size distribution due to reaction, fragmentation, attrition addition fuel, air and inert material inlet; devolatilization and combustion kinetics of volatiles; char combustion including particle excess temperature; emission calculations for SOz, CO, NO, and tar. To simulate these complex processes it was necessary to make compromises, e.g. simplification of the three-dimensional flow structures like secondary air or fuel feeding. The advantage of one-dimensional modelling is the short computing time and the possibility to describe and analyse detail operations and their consequences with regard to the reaction processes. With the help of this model the performance of fluidized bed systems and the process appreciation can be improved.
(energy applications
in industry)
temperature is well below the turbine inlet temperature of the current gas turbines, a topping gas turbine cycle has been proposed that can enhance the cycle efficiency of the conventional PFBC plants. In the topping cycle a recuperated gas turbine fuelled with natural gas utilizes the coal combustion heat to preheat the compressed air before the gas turbine combustor. An influence of such an ‘external heat recuperation’ on efficiency, power and total fuel costs for various proportions of used coal and natural gas in the proposed advanced PFBC plant has been analysed. 02/02180 Repair welding of cracked steam turbine blades using austenitic and martensitic stainless-steel consumables Bhaduri, A. K. e/ crl. Nuclear Engineering and Design, 2001, 206, (2-3), 249-259.
The procedure for repair welding of cracked steam turbine blades made of martensitic stainless steel has been developed using the gas tungsten arc welding process. Weld procedures were developed using both ER 316L austenitic and ER 410 martensitic stainless-steel filler wire. The overall development of the repair welding procedure included selection of welding consumables (for austenitic filler metal), optimization of post-weld heat treatment parameters, selection of suitable method for local pre-heating and post-weld heat treatment (PWHT) of the blades, determination of mechanical properties of weldments in as-welded and PWHT conditions, and microstructural examination. After various trials using different procedures, the procedure of local PWHT (and preheating when using martensitic stainless-steel filler wire) using electrical resistance heating on the top surface of the weldment and monitoring the temperature by placing a thermocouple at the bottom of the weld was found to give the most satisfactory results. These procedures have been developed and/or applied for repair welding of cracked blades in steam turbines. ;2&?‘l’lF
Research
on high speed diesel engine
using with
Zhang,
W. CI crl. Procerdings - Annrrul Inlernationul Pittsburgh Conference, 2000, (I 7). 736-744. nations have had grave concerns h recent years, oil importing
Cnal
about the security of oil supply and price volatility in the OPEC dominated market place and are seeking to reduce their dependence on oil. Ultra clean micronized coal water fuel (UCMCWF) are emerging as the leading alternative to oil and their use is being aggressively pursed in China, Italy and Japan. In China there are millions of diesel engines working in agricultural fields and small power stations. In laboratories using UCMCWF as an alternative oil fuel have been made using Datong coal with coal containing less than 1% ash, viscosity less than 500 mPa s and concentration between 50% and 6096, used UCMCWF in high speed diesel engine have been tested successfully. The testing result indicated that UCMCWF can well work in small high speed diesel engines when modifying nozzle and oil pump system of diesel engines. 02/02182 Second-generation WSOlG gas turbine Robertson, A. er al. Proceedings Nuidixd
Bed Cnmhusrion,
200
PFB plant performance of I/W Inrernational
1, (I 6),
1338-l
with
Conference
on
344.
Research is being conducted under United States Department of Energy Contract DE-AC21-86MC21023 to develop a new type of coalfired plant for electric power generation. A second-generation or advanced pressurized circulating fluidized bed combustion (APCFB) plant promises efficiencies greater than 46%, with emissions and cost of electricity significantly lower than those of conventional pulverizedcoal-fired plants with scrubbers. The APCFB plant incorporates partial gasification of coal in a carbonizer, combustion of carbonizer char in a pressurized circulating fluidized bed combustor (PCFB), and combustion of carbonizer syngas in a topping combustor to achieve gas turbine inlet temperatures of 2300°F and higher. After completing pilot plant tests of a carbonizer, a PCFB, and a gas turbine topping combustor, all developed for this new plant, a higher heating value efficiency of 46.2% was calculated for the plant. In that analysis, the plant operated with a Siemens Westinghouse 501F gas turbine and a conventional 2400 psig steam cycle with 1000°F superheat and reheat steam and a 21-m. mercury condenser back pressure. This paper identifies the efficiency gains that this plant will achieve by using a more advanced Siemens Westinghouse W507 G gas turbine together with superheat and reheat steam temperatures increased to 1050°F. 02102183 The gas turbine in a power plant with pressurized circulating fluidized-bed combustion Stuhlmueller, F. el al. Proceedings of the Intrrnutionol Conference on Fluidixd Bed Combustion, 2001, (16), 1357-1370. The objective of introducing the circulating variant of pressurized fluidized bed combustion is coupled with the intention to simultaneously implement this technology with standard gas turbines designed for combusting high-grade fuels such as natural gas and 282
Fuel and Energy Abstracts
July 2002
distillate fuel oil. This presentation uses the commercially marketed Siemens gas turbines to illustrate the associated requirements imposed on the coal conversion system and hot gas cleanup as well as necessary modifications to the gas turbine. The report focuses on both power plants equipped with conventional circulating pressurized fluidized bed combustion (1st generation PCFB) and those with partial coal gasification (2nd generation PCFB).
11
PROCESS HEATING, POWER AND INCINERATION Energy
applications
in industry
02/02184 A coal-firing oil heating furnace Tang, M. PCT Int. Appl. WO 01 86,214 (Cl. F24H1/28), 15 Nov 2001, CN Appl. 2,000,227,722, 31 Mar 2000. 21. (In Chinese) A coal-firing oil heating furnace, where its hearth is in the furnace shell, and the intracavity of the hearth is separated from the intracavity of the furnace shell. The lower ends of the fire-tubes are communicated with the hearth, and the upper ends of the fire-tubes are communicated with the flue. There is an oil jacket containing the heat-transferring oil between the outer surface of the hearth and the inner surface of the furnace shell. The jacket is divided into several units by baffle plates, and the heat-transferring oil is forced circulating through each unit by an inner circulating pump, further an outer circulating pump is used to send the heat-transferring oil to the service position and takes it back. The invention can reduce the heating cost of the heat-transferring oil greatly and can avoid carbonization or coking. The invention can be applied to the circulating and heating of the heat-transferring oil in the industry of rubber, shoes material, textiles, dye printing, chemical engineering. An extended version of the countercurrent back02/02185 mixing model suitable for solid mixing in two dimensional fluidized beds Abanades, J. C. and Grass, G. Recrnrs Prog. Genie Procede.s. 2000, 14, (76), 551-558. A new mathematical model to describe axial and lateral mixing in fluidized beds is presented. The model is an extension of previous versions of the countercurrent backmixing model that were restricted to axial mixing only. The fluidized bed is divided in parallel ‘mixing columns’, that are convective currents induced by the bubbles. Each mixing column has a central upflowing stream of solids and two adjacent moving downwards. The practical application of the model requires a minimum knowledge of the bubble properties and the definition of one empirical parameter: the exchange coefficient between counter-current phase, Kw, The model can be rapidly solved with the proposed algorithm and reproduces semi-quant, the main features observed in mixing experiments carried out in a bidimensional fluidized bed of coal and PVC as tracer. 02/02186 Benefits of one-dimensional simulation of fluidized bed systems Hiller, R. and Faulhaber, S. Proc. Anrrtr. Inr. Pirrshurgh Coal Conf., 2000, (17), 2059-2078. Two examples of a fluidized bed system are presented to point out the possibilities and limits of the onedimensional and three-dimensional modelling A model developed by Fraunhofer UMSICHT was used for the one-dimensional simulation, the three-dimensional modelling was based on a CFD code. The onedimensional simulation tool is able to predict the operating behaviour of a bubbling tluidized bed combustor, circulating fluidized bed combustor as well as gasifiers. The following features are integrated: fluid dynamics of the gas phase and the solid matter particle size distribution due to reaction, fragmentation, attrition addition fuel, air and inert material inlet; devolatilization and combustion kinetics of volatiles; char combustion including particle excess temperature; emission calculations for SOz, CO, NO, and tar. To simulate these complex processes it was necessary to make compromises, e.g. simplification of the three-dimensional flow structures like secondary air or fuel feeding. The advantage of one-dimensional modelling is the short computing time and the possibility to describe and analyse detail operations and their consequences with regard to the reaction processes. With the help of this model the performance of fluidized bed systems and the process appreciation can be improved.