Lignin and cellulose chemicals were used as artificial biomass components to make-up a simulated biomass. Alkali and Alkaline Earth Metal (AAEM) as well as volatile matter contents in these chemicals were much differe...Lignin and cellulose chemicals were used as artificial biomass components to make-up a simulated biomass. Alkali and Alkaline Earth Metal (AAEM) as well as volatile matter contents in these chemicals were much different from each other. Co-gasification of coal with simulated biomass shows improved conversion characteristics in comparison to the average calculated from separate conversion of coal and simulated biomass. Two conversion synergetic peaks were observed whereby the first peak occurred around 400℃ while the second one occurred above 800℃. Although co-gasification of coal with lignin that has high AAEM content also shows two synergy peaks, the one at higher temperature is dominant. Co-gasification of coal with cellulose shows only a single synergy peak around 400℃ indicating that synergy at low temperature is related with interaction of volatiles. Investigation of morphology changes during gasification of lignin and coal, suggests that their low reactivity is associated with their solid shape maintained even at high temperature.展开更多
Tar catalytic removal by char is a promising technology for gasification process because of its porous structure,good catalytic activity,low cost,and easy to treatment after deactivation.To provide comprehensive infor...Tar catalytic removal by char is a promising technology for gasification process because of its porous structure,good catalytic activity,low cost,and easy to treatment after deactivation.To provide comprehensive information on the tar catalytic removal by char,this study focuses on the ongoing efforts and advances from fundamental researches to the industrial applications.The tar removal efficiency by char much depends on reaction conditions and char property,such as char origin,porous structure,the functional group on char surface,carbon structure,and AAEM components.The typical reaction kinetics,reaction mechanism,and the deactivation,will be introduced.Then,for the different gasification processes,the potential or typical applications of tar removal by char are discussed and compared.Finally,a comprehensive analysis and improvement in scaling up,commercializing tar removal technologies and integrating the gasification process,are also evaluated and analyzed in this review.展开更多
A series of related experiments were carried out based on prepared hydrocracking catalyst, Catalyst-HC. Ni & W and USY molecular sieve were selected as the hydrogenation active component and the cracking component...A series of related experiments were carried out based on prepared hydrocracking catalyst, Catalyst-HC. Ni & W and USY molecular sieve were selected as the hydrogenation active component and the cracking component of Catalyst-HC, respectively. Meanwhile, a kinetic model for paraffin conversion was constructed based on paraffin conversion law. Results obtained through this work indicate that the impact of H_(2)-pressure is relatively complex. As the H_(2)-pressure changes, the degree of hydrocracking reaction may be influenced by both hydrogen supply capacity and hydrogen proton concentration. Obtained conversion priority for three types of hydrocarbons on USY molecular sieve is as follows, aromatic ≫ cycloalkane > paraffin. Aromatic content in SRGO can affect its paraffin-retention in Hydro-D. Compared with the hydrotreating of SRGO with low aromatic content, when SRGO with relatively higher aromatic content is hydrotreated, its paraffin-retention is higher and its paraffin loss is also relatively smaller. Base on constructed model, the calculated values of SRGO-BJ conversion rate and paraffin-retention in Hydro-D are within ±10 % and ±5 % error lines, respectively. Thus, model schematic diagram is reasonable and can provide modeling reference for relevant model research.展开更多
Alkali contents with low melting points in the ash of woody biomass vaporize during the biomass gasification process, damaging various downstream energy conversion devices, such as the solid oxide fuel cells (SOFCs). ...Alkali contents with low melting points in the ash of woody biomass vaporize during the biomass gasification process, damaging various downstream energy conversion devices, such as the solid oxide fuel cells (SOFCs). In this study, the degradation of SOFC anodes by the deposition of potassium compounds (KCl, K_(2)CO_(3), and KOH) was investigated. An aqueous solution of potassium compounds was dripped onto the anode surface of the SOFC button cell at room temperature. After drying at 343 K, 6.964 10^(-6) mol KCl, 6.964 10^(-6) mol KOH, and 3.482 10^(-6) mol K_(2)CO_(3) was deposited on the anode. Button cells with the deposition of K compounds were employed for power generation experiments at 1023 K with the supply of artificial syngas from biomass gasification. After the power generation experiments, the surface structures of the anodes were microscopically analyzed using the SEM and EDS. As a result, K compounds hardly affected the OCV of SOFC. With the addition of KCl, no apparent change in the anode structure was observed, and only a slight KCl deposit was detected. However, chloride tends to be chemisorbed on Ni, increasing the ohmic resistance as well as the adsorption/desorption resistance. However, KOH transformed to K_(2)CO_(3) and then remained massively on the anode, which was clearly observed in the SEM images. K_(2)CO_(3) significantly decreased the cell voltage under a current density of 100 mA·cm−2. Through impedance analyses, this voltage drop was mainly attributed to the ohmic resistance and gas diffusion resistance. However, there is no evidence that this deposit degrades Ni particles.展开更多
文摘Lignin and cellulose chemicals were used as artificial biomass components to make-up a simulated biomass. Alkali and Alkaline Earth Metal (AAEM) as well as volatile matter contents in these chemicals were much different from each other. Co-gasification of coal with simulated biomass shows improved conversion characteristics in comparison to the average calculated from separate conversion of coal and simulated biomass. Two conversion synergetic peaks were observed whereby the first peak occurred around 400℃ while the second one occurred above 800℃. Although co-gasification of coal with lignin that has high AAEM content also shows two synergy peaks, the one at higher temperature is dominant. Co-gasification of coal with cellulose shows only a single synergy peak around 400℃ indicating that synergy at low temperature is related with interaction of volatiles. Investigation of morphology changes during gasification of lignin and coal, suggests that their low reactivity is associated with their solid shape maintained even at high temperature.
文摘Tar catalytic removal by char is a promising technology for gasification process because of its porous structure,good catalytic activity,low cost,and easy to treatment after deactivation.To provide comprehensive information on the tar catalytic removal by char,this study focuses on the ongoing efforts and advances from fundamental researches to the industrial applications.The tar removal efficiency by char much depends on reaction conditions and char property,such as char origin,porous structure,the functional group on char surface,carbon structure,and AAEM components.The typical reaction kinetics,reaction mechanism,and the deactivation,will be introduced.Then,for the different gasification processes,the potential or typical applications of tar removal by char are discussed and compared.Finally,a comprehensive analysis and improvement in scaling up,commercializing tar removal technologies and integrating the gasification process,are also evaluated and analyzed in this review.
基金supported by National Key R&D Program of China(No.2021YFA1501204)SINOPEC Research Program(Grant 118022-2).
文摘A series of related experiments were carried out based on prepared hydrocracking catalyst, Catalyst-HC. Ni & W and USY molecular sieve were selected as the hydrogenation active component and the cracking component of Catalyst-HC, respectively. Meanwhile, a kinetic model for paraffin conversion was constructed based on paraffin conversion law. Results obtained through this work indicate that the impact of H_(2)-pressure is relatively complex. As the H_(2)-pressure changes, the degree of hydrocracking reaction may be influenced by both hydrogen supply capacity and hydrogen proton concentration. Obtained conversion priority for three types of hydrocarbons on USY molecular sieve is as follows, aromatic ≫ cycloalkane > paraffin. Aromatic content in SRGO can affect its paraffin-retention in Hydro-D. Compared with the hydrotreating of SRGO with low aromatic content, when SRGO with relatively higher aromatic content is hydrotreated, its paraffin-retention is higher and its paraffin loss is also relatively smaller. Base on constructed model, the calculated values of SRGO-BJ conversion rate and paraffin-retention in Hydro-D are within ±10 % and ±5 % error lines, respectively. Thus, model schematic diagram is reasonable and can provide modeling reference for relevant model research.
文摘Alkali contents with low melting points in the ash of woody biomass vaporize during the biomass gasification process, damaging various downstream energy conversion devices, such as the solid oxide fuel cells (SOFCs). In this study, the degradation of SOFC anodes by the deposition of potassium compounds (KCl, K_(2)CO_(3), and KOH) was investigated. An aqueous solution of potassium compounds was dripped onto the anode surface of the SOFC button cell at room temperature. After drying at 343 K, 6.964 10^(-6) mol KCl, 6.964 10^(-6) mol KOH, and 3.482 10^(-6) mol K_(2)CO_(3) was deposited on the anode. Button cells with the deposition of K compounds were employed for power generation experiments at 1023 K with the supply of artificial syngas from biomass gasification. After the power generation experiments, the surface structures of the anodes were microscopically analyzed using the SEM and EDS. As a result, K compounds hardly affected the OCV of SOFC. With the addition of KCl, no apparent change in the anode structure was observed, and only a slight KCl deposit was detected. However, chloride tends to be chemisorbed on Ni, increasing the ohmic resistance as well as the adsorption/desorption resistance. However, KOH transformed to K_(2)CO_(3) and then remained massively on the anode, which was clearly observed in the SEM images. K_(2)CO_(3) significantly decreased the cell voltage under a current density of 100 mA·cm−2. Through impedance analyses, this voltage drop was mainly attributed to the ohmic resistance and gas diffusion resistance. However, there is no evidence that this deposit degrades Ni particles.
