Chemical-looping gasification （CLG） is a novel process for syngas generation from solid fuels, sharing the same basic principles as chemical-looping combustion （CLC）. It also uses oxygen carriers （mainly metal ox...Chemical-looping gasification （CLG） is a novel process for syngas generation from solid fuels, sharing the same basic principles as chemical-looping combustion （CLC）. It also uses oxygen carriers （mainly metal oxide and calcium sulfate） to transfer heat and oxygen to the fuel. In this paper, the primary investigation into the CLG process with CaSO4 as oxygen carrier was carried out by thermodynamic analysis and experiments in the tube reactor. Sulfur-contained gas emission was mainly H2S rather than SO2 in the CLG process, showing some different features from the CLC. The mass and heat balance of CLG processes were calculated thermodynamically to determinate the auto-thermal operating conditions with different CaSO4/C and steam/C molar ratios. It was found that the CaSO4/C molar ratio should be higher than 0.2 to reach auto-thermal balance. The effect of temperature on the reactions between oxygen carrier and coal was investigated based on Gibbs free energy minimum method and ex- perimental results. It indicated that high temperature favored the CLG process in the fuel reactor and part of syngas was consumed to compensate for auto-thermal system.展开更多
Fly ash is a fine and dispersed powder discharged from power station after the coal being burned. With the deepening of people’s recognition about the pollution problem of fly ash, the ways of utilizing fly ash are g...Fly ash is a fine and dispersed powder discharged from power station after the coal being burned. With the deepening of people’s recognition about the pollution problem of fly ash, the ways of utilizing fly ash are gradually increasing. Utilizing value of fly ash is closely related to the unburned carbon content.On the basis of analysis of modern testing method,a fundamental thinking is theoretically posed for decreasing unburned carbon content from fly ash by a dry removing carbon technology. The triboelectric separation method shown that the above mentioned thinking of dry removing carbon from fly ash is practical.展开更多
This paper discusses the evolution regularity and the absorption characters of sulfide for bituminous briquette burned in a horizontal burning fornace. The evolution rate of sulphur is affected by some factors, such a...This paper discusses the evolution regularity and the absorption characters of sulfide for bituminous briquette burned in a horizontal burning fornace. The evolution rate of sulphur is affected by some factors, such as the sulphur content in the burning coal, burning time and the mean excess air coefficient in the furnace. With processing the experimental result, the calculation related expression has been obtained to predict the evolution rate of sulfide. The sulphur absorption efficiency of briquette is affected by tbe factors such as the character of the sulphur sorbent, the type of the coal and the operating parameters. By means of appropriately adjusting the calciumsulphur mole ratio, the mean excess air coefficient and the time-interval between pushing two layer briquettes, a high sulphur absorption efficiency (>74% ) can be obtained.展开更多
The microwave technology was introduced for the desulfurization of diesel fuel. The atmosphericsecond side-cut diesel fraction, which was supplied by Liaohe Petrochemical Company, was desulfurized by anoxidation proce...The microwave technology was introduced for the desulfurization of diesel fuel. The atmosphericsecond side-cut diesel fraction, which was supplied by Liaohe Petrochemical Company, was desulfurized by anoxidation process under microwave irradiation. Hydrogen peroxide (H2O2), can oxidize the sulfur compounds indiesel fuel selectively and convert them into sulfones. Based on the rule of dissolution by similar substances,these sulfones are removed from diesel fuel because they could be dissolved in solvent phase. So the sulfurcontent of diesel fuel is decreased. The influence of the concentration of oxidizing reagent, solvent phase to oilphase volume ratio (S/O), irradiation pressure, irradiation time, and the irradiation power have been investigated.The optimum conditions for the refining process was determined. The sulfur removal rate was 59.7% under theoptimum conditions of 8%H2O2, S/O=0.25, 0.05MPa, 6 min, and 375W, respectively. When no microwave irradia-tion was applied, the removal rate was 11.5% only.展开更多
基金Supported by the National~ Natural Science Foundation of China （20876079）, the Natural Science Funds for Distinguished Young Scholar in Shandong Province （JQ200904）, and Shandong Province Key Technologies Research and Development Program of China （2008GG 10006010, 2009GG 10007001）.
文摘Chemical-looping gasification （CLG） is a novel process for syngas generation from solid fuels, sharing the same basic principles as chemical-looping combustion （CLC）. It also uses oxygen carriers （mainly metal oxide and calcium sulfate） to transfer heat and oxygen to the fuel. In this paper, the primary investigation into the CLG process with CaSO4 as oxygen carrier was carried out by thermodynamic analysis and experiments in the tube reactor. Sulfur-contained gas emission was mainly H2S rather than SO2 in the CLG process, showing some different features from the CLC. The mass and heat balance of CLG processes were calculated thermodynamically to determinate the auto-thermal operating conditions with different CaSO4/C and steam/C molar ratios. It was found that the CaSO4/C molar ratio should be higher than 0.2 to reach auto-thermal balance. The effect of temperature on the reactions between oxygen carrier and coal was investigated based on Gibbs free energy minimum method and ex- perimental results. It indicated that high temperature favored the CLG process in the fuel reactor and part of syngas was consumed to compensate for auto-thermal system.
文摘Fly ash is a fine and dispersed powder discharged from power station after the coal being burned. With the deepening of people’s recognition about the pollution problem of fly ash, the ways of utilizing fly ash are gradually increasing. Utilizing value of fly ash is closely related to the unburned carbon content.On the basis of analysis of modern testing method,a fundamental thinking is theoretically posed for decreasing unburned carbon content from fly ash by a dry removing carbon technology. The triboelectric separation method shown that the above mentioned thinking of dry removing carbon from fly ash is practical.
文摘This paper discusses the evolution regularity and the absorption characters of sulfide for bituminous briquette burned in a horizontal burning fornace. The evolution rate of sulphur is affected by some factors, such as the sulphur content in the burning coal, burning time and the mean excess air coefficient in the furnace. With processing the experimental result, the calculation related expression has been obtained to predict the evolution rate of sulfide. The sulphur absorption efficiency of briquette is affected by tbe factors such as the character of the sulphur sorbent, the type of the coal and the operating parameters. By means of appropriately adjusting the calciumsulphur mole ratio, the mean excess air coefficient and the time-interval between pushing two layer briquettes, a high sulphur absorption efficiency (>74% ) can be obtained.
文摘The microwave technology was introduced for the desulfurization of diesel fuel. The atmosphericsecond side-cut diesel fraction, which was supplied by Liaohe Petrochemical Company, was desulfurized by anoxidation process under microwave irradiation. Hydrogen peroxide (H2O2), can oxidize the sulfur compounds indiesel fuel selectively and convert them into sulfones. Based on the rule of dissolution by similar substances,these sulfones are removed from diesel fuel because they could be dissolved in solvent phase. So the sulfurcontent of diesel fuel is decreased. The influence of the concentration of oxidizing reagent, solvent phase to oilphase volume ratio (S/O), irradiation pressure, irradiation time, and the irradiation power have been investigated.The optimum conditions for the refining process was determined. The sulfur removal rate was 59.7% under theoptimum conditions of 8%H2O2, S/O=0.25, 0.05MPa, 6 min, and 375W, respectively. When no microwave irradia-tion was applied, the removal rate was 11.5% only.
