To reasonably utilize the coal direct liquefaction residue(DLR), contrasting research on the co-pyrolysis between different low-rank coals and DLR was investigated using a TGA coupled with an FT-IR spectrophotometer a...To reasonably utilize the coal direct liquefaction residue(DLR), contrasting research on the co-pyrolysis between different low-rank coals and DLR was investigated using a TGA coupled with an FT-IR spectrophotometer and a fixed-bed reactor. GC–MS, FTIR, and XRD were used to explore the reaction mechanisms of the various co-pyrolysis processes. Based on the TGA results, it was confirmed that the tetrahydrofuran insoluble fraction of DLR helped to catalyze the conversion reaction of lignite. Also, the addition of DLR improved the yield of tar in the fixed-bed, with altering the composition of the tar. Moreover, a kinetic analysis during the co-pyrolysis was conducted using a distributed activation energy model. The co-pyrolysis reactions showed an approximate double-Gaussian distribution.展开更多
DCLR-P was prepared by direct coal liquefaction residue (DCLR) with ash removal.In the present experiments,mesocarbon microbeads (MCMBs) were prepared by co-carbonization of coal tar pitch (CTP) and DCLR-P.With the in...DCLR-P was prepared by direct coal liquefaction residue (DCLR) with ash removal.In the present experiments,mesocarbon microbeads (MCMBs) were prepared by co-carbonization of coal tar pitch (CTP) and DCLR-P.With the increase of DCLR-P content,the yield of MCMBs increased from 47.8% to 56.8%.At the same time,the particle sizes distribution of MCMBs was narrowed,resulting in the decrease of D9o/D10 ratio from 154.88 to 6.53.The results showed that DCLR-P had a positive effect on the preparation of MCMBs.1H-NMR,FTIR,SEM and XRD were used to analyze the mechanisms and characteristics of MCMBs prepared by co-carbonization of CTP and DCLR-P.The results showed that the Proton Donor Quality Index (PDQI) of DCLR-P was 13.32,significantly higher than that of CTP (0.83).This indicated that DCLR-P had more naphthenic structure than CTP,which leads to hydrogen transferring in polycondensation reaction.The aliphatic structure of DCLR-P can improve the solubility and fusibility of mesophase,thereby making the structure of MCMBs more structured.The microstructure of the graphitized MCMBs had a substantially parallel carbon layer useful for its electrical performance.The performance of graphitized MCMBs as a negative electrode material for Li-ion batteries was tested.The particle sizes,tap density,specific surface area and initial charge-discharge efficiency of graphitized MCMBs met the requirements of CMB-I in GB/T-24533-2009.However,the initial discharge capacity of graphitized MCMB was only 296.3 mA h g-1 due to the low degree of graphitization of MCMBs.展开更多
The compatibility between direct coal liquefaction residue(DCLR) and five kinds of pure bitumen(Shell-90,SK-90, ZSY-70, DM-70 and KLMY-50) was evaluated in this study. The rheological characteristics, glass transition...The compatibility between direct coal liquefaction residue(DCLR) and five kinds of pure bitumen(Shell-90,SK-90, ZSY-70, DM-70 and KLMY-50) was evaluated in this study. The rheological characteristics, glass transition temperatures(T_g), solubility parameters(SP) and SARA(saturates, aromatics, resins, and asphaltenes) fractions of DCLR,five kinds of pure bitumen and their blends(named as DCLR modified bitumen) were measured using the dynamic shear rheometer(DSR), differential scanning calorimetry(DSC), viscosity, and SARA tests, respectively. And the compatibility between DCLR and pure bitumen was characterized with three approaches, viz. the Cole-Cole plot,T_g, and the solubility parameter difference(SPD) method. Since each method has its own working mechanism, the compatibility ranking for the DCLR and five kinds of pure bitumen is slightly different according to the three approaches. However, the difference is pretty close and sometimes can be ignored. The general compatibility ranking decreases in the following order: Shell-90≈SK-90>DM-70≈ZSY-70>KLMY-50, which is affected by the asphaltenes content and the colloid index(I_c) value in the pure bitumen. Pure bitumen with lower asphaltenes content and colloid index(I_c) value has better compatibility with DCLR.展开更多
Gasification of extraction residue(ER) from direct coal liquefaction with pulverized coal is an efficient way for the utilization of carbonaceous wastes, which improve the overall efficiency of direct coal liquefactio...Gasification of extraction residue(ER) from direct coal liquefaction with pulverized coal is an efficient way for the utilization of carbonaceous wastes, which improve the overall efficiency of direct coal liquefaction technology. The discharge characteristics of ER mixing with pulverized coal is important paraments for its gasification process, which is seldom studied in the literature. In this study, the discharge characteristics of the pulverized coal(M1) as well as its mixture with ER(M2) were systematically investigated in an atmospheric pressure partial fluidization silo with different fluidization apparent velocity. It was observed that although M2 is a viscous powder with lower flowability than M1, the mass flow rate of M2 is 65% higher than M1 at the 3.7 mm·s-1apparent gas velocity. M2 exhibits the properties of Geldart A type powder, which improves the mass flow rate and stability of the discharged material. The mass flow rate of both M1 and M2 first increases and then slowly decreases with the increase of apparent gas velocity of the fluidizing air, which means the discharge process of M1 and M2 can be optimized by the apparent gas velocity.展开更多
Utilizing the extraction residue(ER)of direct coal liquefaction residue as a gasification feedstock has significant economic value.But the characteristic of high ash and iron in the ER would increase the risk of corro...Utilizing the extraction residue(ER)of direct coal liquefaction residue as a gasification feedstock has significant economic value.But the characteristic of high ash and iron in the ER would increase the risk of corrosion of the refractory materials and affect the long-term operation of the gasifier.In this work,corrosion experiments of molten slag derived from a mixture of 20 wt%ER and 80 wt%coal on a high-chromia refractory brick and SiC brick were carried out using a rotary-drum furnace in a simulated gasification atmosphere.The experimental results show that the viscosity of the poured slag is larger as compared to the initial ash sample at the same temperature,which suggests that the viscosity-temperature relationship of the poured slag should be used as the reference for the operation temperature of the gasifier to ensure that the slag can flow during operation.For a high-chromia refractory brick,iron oxides in molten slag could react with Cr_(2)O_(3) in the refractory matrix but,because the aggregate was not found to be damaged,the damage to the matrix structure was the key factor for causing the corrosion of the high-chromia refractory brick.Metallic iron was observed in the exposed SiC brick,which indicated that the reaction between the iron oxides in the slag and SiC occurred,forming metallic iron and SiO_(2).The corrosion of a SiC brick by molten slag depended mainly on the dissolution of Al_(2)O_(3) particles and the reaction between iron oxides in the molten slag and SiC particles.Therefore,the high iron content in coal ash had a serious influence on the corrosion of refractory materials.More efforts need to be made on coal blended with ER as a gasification feedstock in the future.展开更多
In recent decades,modified asphalt materials have been used in enhancing the traffic load on the roads.The main objective of this paper is to explore the modifi cation effect of direct coal liquefaction residue(DCLR)o...In recent decades,modified asphalt materials have been used in enhancing the traffic load on the roads.The main objective of this paper is to explore the modifi cation effect of direct coal liquefaction residue(DCLR)on as-phalt binders and investigate the effectiveness of DCLR in improving the performance of asphalt road.This paper prepared modifi ed petroleum as-phalt under diff erent process conditions and tested its penetration,softening point and ductility index.Based on the experimental data,according to gray correlation degree,the performance for the asphalt was compared.The performance for the modified asphalt is simulated and predicted using poly-nomial functions.The modifi ed asphalt was analyzed by FT-IR,TGA,SEM and HPLC.The results show that the optimal process conditions for DCLR modifi ed asphalt are shear mixing time of 45 min,shear mixing tempera-ture of 150℃ and shear mixing rate of 4000 r/min.The predicted fit with the experimental data of 0.993 further demonstrates the effectiveness of the method.The characterization results show no significant chemical change between the DCLR and the asphalt.DCLR can significantly improve the high temperature performance and water stability of the asphalt,but it has little impact on its low temperature performance.展开更多
Based on the specifications of ASTM D571095 and BSI BS-3690 for Trinidad Lake Asphalt(TLA) modified asphalt,two residues(CLA1 and CLA2)from direct coal liquefaction(DCL) were evaluated for using as high grade paving a...Based on the specifications of ASTM D571095 and BSI BS-3690 for Trinidad Lake Asphalt(TLA) modified asphalt,two residues(CLA1 and CLA2)from direct coal liquefaction(DCL) were evaluated for using as high grade paving asphalt modifier.TLA was used as comparison.The results show that CLA1-and CLA2-modified asphalt with 7% of CLA1 or CLA2 addition has similar modification ability as 20% TLA-modified asphalt.The modified asphalts meet the specifications for 40～55 or 50 penetration grade.The penetration ratio of CLA2-modified asphalt after TFOT is significantly higher,which indicates its supreme ability to against the temperature aging.Preliminary study implies that DCL residues may be a suitable alternative additive for producing TLA-type modified asphalt.Furthermore it was also found that with increasing amount of CLA1 or CLA2 addition the softening point of the modified asphalts increase and the penetration value and the ductility decrease.展开更多
基金Supported by National High-tech Research and Development Program of China(2011AA05A2021)the National Natural Science Foundation of China(21536009)Science and Technology Plan Projects of Shaanxi Province(2017ZDCXL-GY-10-03).
文摘To reasonably utilize the coal direct liquefaction residue(DLR), contrasting research on the co-pyrolysis between different low-rank coals and DLR was investigated using a TGA coupled with an FT-IR spectrophotometer and a fixed-bed reactor. GC–MS, FTIR, and XRD were used to explore the reaction mechanisms of the various co-pyrolysis processes. Based on the TGA results, it was confirmed that the tetrahydrofuran insoluble fraction of DLR helped to catalyze the conversion reaction of lignite. Also, the addition of DLR improved the yield of tar in the fixed-bed, with altering the composition of the tar. Moreover, a kinetic analysis during the co-pyrolysis was conducted using a distributed activation energy model. The co-pyrolysis reactions showed an approximate double-Gaussian distribution.
基金Supported by National Key Research and Development Program of China(2018YFB0604601)and the Technology Innovation Fund of China coal research institute(2016CX01).
文摘DCLR-P was prepared by direct coal liquefaction residue (DCLR) with ash removal.In the present experiments,mesocarbon microbeads (MCMBs) were prepared by co-carbonization of coal tar pitch (CTP) and DCLR-P.With the increase of DCLR-P content,the yield of MCMBs increased from 47.8% to 56.8%.At the same time,the particle sizes distribution of MCMBs was narrowed,resulting in the decrease of D9o/D10 ratio from 154.88 to 6.53.The results showed that DCLR-P had a positive effect on the preparation of MCMBs.1H-NMR,FTIR,SEM and XRD were used to analyze the mechanisms and characteristics of MCMBs prepared by co-carbonization of CTP and DCLR-P.The results showed that the Proton Donor Quality Index (PDQI) of DCLR-P was 13.32,significantly higher than that of CTP (0.83).This indicated that DCLR-P had more naphthenic structure than CTP,which leads to hydrogen transferring in polycondensation reaction.The aliphatic structure of DCLR-P can improve the solubility and fusibility of mesophase,thereby making the structure of MCMBs more structured.The microstructure of the graphitized MCMBs had a substantially parallel carbon layer useful for its electrical performance.The performance of graphitized MCMBs as a negative electrode material for Li-ion batteries was tested.The particle sizes,tap density,specific surface area and initial charge-discharge efficiency of graphitized MCMBs met the requirements of CMB-I in GB/T-24533-2009.However,the initial discharge capacity of graphitized MCMB was only 296.3 mA h g-1 due to the low degree of graphitization of MCMBs.
基金sponsored by the National Natural Science Foundation of China (51478028 and 51778038)the Program for Changjiang Scholars and Innovative Research Team in Universities(IRT-17R06)
文摘The compatibility between direct coal liquefaction residue(DCLR) and five kinds of pure bitumen(Shell-90,SK-90, ZSY-70, DM-70 and KLMY-50) was evaluated in this study. The rheological characteristics, glass transition temperatures(T_g), solubility parameters(SP) and SARA(saturates, aromatics, resins, and asphaltenes) fractions of DCLR,five kinds of pure bitumen and their blends(named as DCLR modified bitumen) were measured using the dynamic shear rheometer(DSR), differential scanning calorimetry(DSC), viscosity, and SARA tests, respectively. And the compatibility between DCLR and pure bitumen was characterized with three approaches, viz. the Cole-Cole plot,T_g, and the solubility parameter difference(SPD) method. Since each method has its own working mechanism, the compatibility ranking for the DCLR and five kinds of pure bitumen is slightly different according to the three approaches. However, the difference is pretty close and sometimes can be ignored. The general compatibility ranking decreases in the following order: Shell-90≈SK-90>DM-70≈ZSY-70>KLMY-50, which is affected by the asphaltenes content and the colloid index(I_c) value in the pure bitumen. Pure bitumen with lower asphaltenes content and colloid index(I_c) value has better compatibility with DCLR.
文摘Gasification of extraction residue(ER) from direct coal liquefaction with pulverized coal is an efficient way for the utilization of carbonaceous wastes, which improve the overall efficiency of direct coal liquefaction technology. The discharge characteristics of ER mixing with pulverized coal is important paraments for its gasification process, which is seldom studied in the literature. In this study, the discharge characteristics of the pulverized coal(M1) as well as its mixture with ER(M2) were systematically investigated in an atmospheric pressure partial fluidization silo with different fluidization apparent velocity. It was observed that although M2 is a viscous powder with lower flowability than M1, the mass flow rate of M2 is 65% higher than M1 at the 3.7 mm·s-1apparent gas velocity. M2 exhibits the properties of Geldart A type powder, which improves the mass flow rate and stability of the discharged material. The mass flow rate of both M1 and M2 first increases and then slowly decreases with the increase of apparent gas velocity of the fluidizing air, which means the discharge process of M1 and M2 can be optimized by the apparent gas velocity.
基金This work was supported by the Science and Technology Innovation Project of CHN Energy(grant number GJNY-21-91)the Science and Technology Innovation Project of CHN Energy(grant number GJNY-20-119)the National Key R&D program of China(grant number 2017YFB0602603).
文摘Utilizing the extraction residue(ER)of direct coal liquefaction residue as a gasification feedstock has significant economic value.But the characteristic of high ash and iron in the ER would increase the risk of corrosion of the refractory materials and affect the long-term operation of the gasifier.In this work,corrosion experiments of molten slag derived from a mixture of 20 wt%ER and 80 wt%coal on a high-chromia refractory brick and SiC brick were carried out using a rotary-drum furnace in a simulated gasification atmosphere.The experimental results show that the viscosity of the poured slag is larger as compared to the initial ash sample at the same temperature,which suggests that the viscosity-temperature relationship of the poured slag should be used as the reference for the operation temperature of the gasifier to ensure that the slag can flow during operation.For a high-chromia refractory brick,iron oxides in molten slag could react with Cr_(2)O_(3) in the refractory matrix but,because the aggregate was not found to be damaged,the damage to the matrix structure was the key factor for causing the corrosion of the high-chromia refractory brick.Metallic iron was observed in the exposed SiC brick,which indicated that the reaction between the iron oxides in the slag and SiC occurred,forming metallic iron and SiO_(2).The corrosion of a SiC brick by molten slag depended mainly on the dissolution of Al_(2)O_(3) particles and the reaction between iron oxides in the molten slag and SiC particles.Therefore,the high iron content in coal ash had a serious influence on the corrosion of refractory materials.More efforts need to be made on coal blended with ER as a gasification feedstock in the future.
文摘In recent decades,modified asphalt materials have been used in enhancing the traffic load on the roads.The main objective of this paper is to explore the modifi cation effect of direct coal liquefaction residue(DCLR)on as-phalt binders and investigate the effectiveness of DCLR in improving the performance of asphalt road.This paper prepared modifi ed petroleum as-phalt under diff erent process conditions and tested its penetration,softening point and ductility index.Based on the experimental data,according to gray correlation degree,the performance for the asphalt was compared.The performance for the modified asphalt is simulated and predicted using poly-nomial functions.The modifi ed asphalt was analyzed by FT-IR,TGA,SEM and HPLC.The results show that the optimal process conditions for DCLR modifi ed asphalt are shear mixing time of 45 min,shear mixing tempera-ture of 150℃ and shear mixing rate of 4000 r/min.The predicted fit with the experimental data of 0.993 further demonstrates the effectiveness of the method.The characterization results show no significant chemical change between the DCLR and the asphalt.DCLR can significantly improve the high temperature performance and water stability of the asphalt,but it has little impact on its low temperature performance.
文摘Based on the specifications of ASTM D571095 and BSI BS-3690 for Trinidad Lake Asphalt(TLA) modified asphalt,two residues(CLA1 and CLA2)from direct coal liquefaction(DCL) were evaluated for using as high grade paving asphalt modifier.TLA was used as comparison.The results show that CLA1-and CLA2-modified asphalt with 7% of CLA1 or CLA2 addition has similar modification ability as 20% TLA-modified asphalt.The modified asphalts meet the specifications for 40～55 or 50 penetration grade.The penetration ratio of CLA2-modified asphalt after TFOT is significantly higher,which indicates its supreme ability to against the temperature aging.Preliminary study implies that DCL residues may be a suitable alternative additive for producing TLA-type modified asphalt.Furthermore it was also found that with increasing amount of CLA1 or CLA2 addition the softening point of the modified asphalts increase and the penetration value and the ductility decrease.
