With focus on investigating the effect of combustor scale on the conversion of fuel-N to NOx and N20, experiments are carried out in three combustors, including single coal particle combustion test rig, laboratory sca...With focus on investigating the effect of combustor scale on the conversion of fuel-N to NOx and N20, experiments are carried out in three combustors, including single coal particle combustion test rig, laboratory scale circulating fluidized-bed boiler (CFB) and full scale CFB in this work. For single coal particle combustion, the majority of f-uel-N (65%-82%) is released as NOx, while only a little (less than 8%) fuel-N yields N20. But in labora- tory scale CFB, the conversion of fuel-N to N20 is increases, but the conversion of fuel-N to NOx is quite less than that of single coal particle combustion. This is because much char in CFB can promote the NOx reduction by in- creasing N20 formation. In full scale CFB, both of the conversion of fuel-N to NOx and the conversion of fuel-N to N20 are smaller than laboratory scale CFB.展开更多
Analysis was performed on the boiler for solid fuels in a corresponding real-thermal load. The tests were conducted with the use of a low-temperature top-loading KWSM water boiler. For control of the burning process, ...Analysis was performed on the boiler for solid fuels in a corresponding real-thermal load. The tests were conducted with the use of a low-temperature top-loading KWSM water boiler. For control of the burning process, three control algorithms were used as implemented in microprocessor temperature controls. The analysis aimed at determination of influence of the control algorithm upon quality of the buming process in conditions of actual demand for thermal energy. The detailed analysis of operating parameters in relation to the variable thermal load of the boiler provided necessary information and made it possible to state that control algorithms do influence quality of the controlled process. Particular attention was paid to a situation, in which demand for thermal energy is decreased.展开更多
A large-scale experimental for multiphase combustion and explosion study was developed and manufactured. The explosion tank consists of a 2 m diameter, 3.5 m long tube and ellipsoidai dames on both ends. The volume of...A large-scale experimental for multiphase combustion and explosion study was developed and manufactured. The explosion tank consists of a 2 m diameter, 3.5 m long tube and ellipsoidai dames on both ends. The volume of the experimental tank is 10 ma. Pressure histories of the explosion pressure can be measured at different locations in the tank. High pressure glass windows of 200~300 mm were used to have access to the visualization of the explosion process. The explosion process of methane/air mixture and methane/coal dust/air mixture initiated by a 40 J electric spark at the center of the tank was studied in the large^scale experimental system. Five pressure sonsars were arranged in the tank with different distances from the ignition point. Ton dust dispersion traits were equipped to eject dust into the tank. A high-speed camera system was used to visualize the flame propagation during the explosion process. The characteristics of the pressure wave and flame propagated in methane/air mixtures and methane/coal dust/air mixtures have been展开更多
One of the most significant human-made methane emission sources is the MSW (municipal solid waste), deposited on sanitary landfills and open dumps. Within this work, an alternative MSW treatment concept is presented...One of the most significant human-made methane emission sources is the MSW (municipal solid waste), deposited on sanitary landfills and open dumps. Within this work, an alternative MSW treatment concept is presented, which could provide a relatively clean waste/biomass-to-energy transformation. The proposed procedure comprises of a combustion and a gasification (or pyrolysis) step, which are consecutively taking place in a two-stage hybrid porous reactor system. The core of the system is two packed bed reactors, in which solid fuel (waste or biomass) is mixed with inert ceramic particles of similar size. This paper overviews the initial experimental investigation of the combustion step of a hybrid mixture, composed of wood pellets (fuel) and alumina balls (inert ceramic particles) in a 250 ram-high batch reactor. The temperature profile along the reactor, the concentration of CO and the flame front propagation velocity were measured as a function of the ceramic particle size (11 and 20 mrn), the inert-to-fuel mass ratio (0:1, 2:1, 3:1) and the airflow rate (30, 42, 60 1/min). Experiments indicate that an increase of the mass ratio of inert-to-fuel material and a decrease of the inert ceramic particles size lead to a decrease of the maximum temperature of the packed hybrid bed. Measured CO concentrations showed strong dependence on the inert ceramic particle size, i.e. the particle size reduction from 20 to 11 mm resulted in a significant reduction of CO-emission peaks. The maximum flame front propagation velocity of 0.2 mm/sec was detected for the airflow of 42 1/min, the particle size of 20 mm and the mass ratio of 3:1.展开更多
The industrial biomass combustor of Halla food factory in Thailand was designed for drying tuna fish product. The purpose of this paper needed to present the design of a factory combustor for producing heat in the dry...The industrial biomass combustor of Halla food factory in Thailand was designed for drying tuna fish product. The purpose of this paper needed to present the design of a factory combustor for producing heat in the drying process by thermal energy from biomass fuel combustion to reduce the investment cost. A drying chamber was made from four concrete walls in the rectangular volume of 4.7 × 4.7 × 2.5 m3 for drying tuna fishes that sliced to small pieces of around 2,680 kg fresh tuna. The hot air tube in the combustor was used for driving hot air to dry fishes in the drying chamber. Heat from acacia wood burning in the combustor with the consumption rate of 50.1 kg/h was transferred by the hot air. The design result was calculated for thermal energy and the efficiency of around 200 kW, and 32%, respectively in the case of 0.62 m3/s hot air flow rate that circulation between the combustor and the drying chamber. The experimental result shows that the moister content of 78.9%wb was decreased to around 13.8%wb in 5 days without petroleum fuel. The drying temperature was controlled at 70℃ continuously for reducing hard containing, and the closed loop tube design for the less of BaP (benzo (a) pyrene) from combustion smoking of the drying industrial process.展开更多
基金Supported by the National Basic Research Program of China(2009CB219802)
文摘With focus on investigating the effect of combustor scale on the conversion of fuel-N to NOx and N20, experiments are carried out in three combustors, including single coal particle combustion test rig, laboratory scale circulating fluidized-bed boiler (CFB) and full scale CFB in this work. For single coal particle combustion, the majority of f-uel-N (65%-82%) is released as NOx, while only a little (less than 8%) fuel-N yields N20. But in labora- tory scale CFB, the conversion of fuel-N to N20 is increases, but the conversion of fuel-N to NOx is quite less than that of single coal particle combustion. This is because much char in CFB can promote the NOx reduction by in- creasing N20 formation. In full scale CFB, both of the conversion of fuel-N to NOx and the conversion of fuel-N to N20 are smaller than laboratory scale CFB.
文摘Analysis was performed on the boiler for solid fuels in a corresponding real-thermal load. The tests were conducted with the use of a low-temperature top-loading KWSM water boiler. For control of the burning process, three control algorithms were used as implemented in microprocessor temperature controls. The analysis aimed at determination of influence of the control algorithm upon quality of the buming process in conditions of actual demand for thermal energy. The detailed analysis of operating parameters in relation to the variable thermal load of the boiler provided necessary information and made it possible to state that control algorithms do influence quality of the controlled process. Particular attention was paid to a situation, in which demand for thermal energy is decreased.
基金supported by the National Natural Science Foundation of China(No.10772032)the Foundation of State Key Lab of Explosion Science and Technology(No.ZDKT08-02-6,and YBKT09-1)
文摘A large-scale experimental for multiphase combustion and explosion study was developed and manufactured. The explosion tank consists of a 2 m diameter, 3.5 m long tube and ellipsoidai dames on both ends. The volume of the experimental tank is 10 ma. Pressure histories of the explosion pressure can be measured at different locations in the tank. High pressure glass windows of 200~300 mm were used to have access to the visualization of the explosion process. The explosion process of methane/air mixture and methane/coal dust/air mixture initiated by a 40 J electric spark at the center of the tank was studied in the large^scale experimental system. Five pressure sonsars were arranged in the tank with different distances from the ignition point. Ton dust dispersion traits were equipped to eject dust into the tank. A high-speed camera system was used to visualize the flame propagation during the explosion process. The characteristics of the pressure wave and flame propagated in methane/air mixtures and methane/coal dust/air mixtures have been
文摘One of the most significant human-made methane emission sources is the MSW (municipal solid waste), deposited on sanitary landfills and open dumps. Within this work, an alternative MSW treatment concept is presented, which could provide a relatively clean waste/biomass-to-energy transformation. The proposed procedure comprises of a combustion and a gasification (or pyrolysis) step, which are consecutively taking place in a two-stage hybrid porous reactor system. The core of the system is two packed bed reactors, in which solid fuel (waste or biomass) is mixed with inert ceramic particles of similar size. This paper overviews the initial experimental investigation of the combustion step of a hybrid mixture, composed of wood pellets (fuel) and alumina balls (inert ceramic particles) in a 250 ram-high batch reactor. The temperature profile along the reactor, the concentration of CO and the flame front propagation velocity were measured as a function of the ceramic particle size (11 and 20 mrn), the inert-to-fuel mass ratio (0:1, 2:1, 3:1) and the airflow rate (30, 42, 60 1/min). Experiments indicate that an increase of the mass ratio of inert-to-fuel material and a decrease of the inert ceramic particles size lead to a decrease of the maximum temperature of the packed hybrid bed. Measured CO concentrations showed strong dependence on the inert ceramic particle size, i.e. the particle size reduction from 20 to 11 mm resulted in a significant reduction of CO-emission peaks. The maximum flame front propagation velocity of 0.2 mm/sec was detected for the airflow of 42 1/min, the particle size of 20 mm and the mass ratio of 3:1.
文摘The industrial biomass combustor of Halla food factory in Thailand was designed for drying tuna fish product. The purpose of this paper needed to present the design of a factory combustor for producing heat in the drying process by thermal energy from biomass fuel combustion to reduce the investment cost. A drying chamber was made from four concrete walls in the rectangular volume of 4.7 × 4.7 × 2.5 m3 for drying tuna fishes that sliced to small pieces of around 2,680 kg fresh tuna. The hot air tube in the combustor was used for driving hot air to dry fishes in the drying chamber. Heat from acacia wood burning in the combustor with the consumption rate of 50.1 kg/h was transferred by the hot air. The design result was calculated for thermal energy and the efficiency of around 200 kW, and 32%, respectively in the case of 0.62 m3/s hot air flow rate that circulation between the combustor and the drying chamber. The experimental result shows that the moister content of 78.9%wb was decreased to around 13.8%wb in 5 days without petroleum fuel. The drying temperature was controlled at 70℃ continuously for reducing hard containing, and the closed loop tube design for the less of BaP (benzo (a) pyrene) from combustion smoking of the drying industrial process.