Article
Energy & Fuels
Haiping Yang, Hao Song, Chuang Zhao, Junhao Hu, Siqin Li, Hanping Chen
Summary: This study investigated the high temperature catalytic gasification of petroleum coke pyrolysis char. Different catalysts were found to have varying effects on the gasification process, with NaAlO2 showing the highest catalytic performance. The addition of NaAlO2 significantly improved the gasification reactivity of petroleum coke pyrolysis char.
Article
Energy & Fuels
Wei Li, Deepak Pudasainee, Rajender Gupta, Wu Yang, Ben Wang, Lushi Sun
Summary: The research found that controlling the gasification temperature of petroleum coke above 1200 degrees Celsius is beneficial for improving gasification reactivity. Petroleum coke with high ash content promotes the decomposition of functional groups to generate active radicals, thereby increasing active sites.
Article
Energy & Fuels
Xianyu Liu, Jiandong Ma, Qi Hong, Shiwei Ma, Huijun Ge, Tao Song
Summary: The study found that potassium can be used as a catalyst to accelerate coke conversion in the chemical looping gasification process, with good catalytic effects. Different potassium introduction modes have different effects on syngas yields and distribution, carbon conversion and potassium evolution. Using potassium to modify coke can achieve higher average carbon conversion rates.
Review
Energy & Fuels
Miao Wang, Yiling Wan, Qinghua Guo, Yonghui Bai, Guangsuo Yu, Yurong Liu, Hong Zhang, Shu Zhang, Juntao Wei
Summary: Petroleum coke and biomass/coal co-gasification is a promising approach for efficiently integrating the individual advantages of different gasification feedstocks with syngas production. Research on syngas production, reactivity characteristics, and synergy behavior of co-gasification is critical. H-2-rich syngas and higher co-gasification reactivity can be acquired under specific conditions, such as high H/C ratio, coal/biomass proportion, gasification temperature, and gasification agent concentration. Synergy behavior in co-gasification shows relationships with free radical migration and AAEMs transfer.
Article
Biochemistry & Molecular Biology
Man Zhang, Hongyu Ban, Zhiqing Wang, Xinning Xiang, Xiaolei Wang, Qian Zhang
Summary: The impact of K(2)CO(3) catalyst on the gasification of petroleum coke was studied. The results showed that increasing the amount of K(2)CO(3) greatly reduced the gasification temperatures of the coke. However, beyond a certain concentration of K+, the catalytic reaction became saturated. Further increase in the catalyst did not inhibit the gasification rate. The vaporization of the catalyst was observed during high-temperature gasification. XRD, Raman spectroscopy, and N-2 adsorption analyses revealed that the presence of the catalyst altered the carbon crystallite structure of the residual coke.
Article
Thermodynamics
Agnieszka Korus, Adam Klimanek, Slawomir Sladek, Andrzej Szlek, Airy Tilland, Stephane Bertholin, Nils Erland L. Haugen
Summary: The process of petcoke conversion in chemical looping combustion technology requires detailed knowledge about the reactions with O-2, CO2, and H2O. Experimental results showed that the reaction with CO2 was slow, and kinetic parameters of petcoke gasification were determined by applying different models to the data obtained from a custom test rig.
Article
Thermodynamics
Tianhong Zhou, Lichao Ge, Qian Li, Long Yang, Longhui Mai, Jing Huang, Yang Wang, Chang Xu
Summary: Isothermal pyrolysis experiments were conducted to optimize the utilization of petroleum coke. Combustion characteristics and gasification properties of petroleum coke and its semi-coke were investigated. Results showed that gas production increased with higher pyrolysis temperatures. The graphitization degree of semi-coke showed a decreasing and then increasing trend, reaching its lowest at 650 degrees C. Combustion performance improved with increased oxygen concentration, while gasification rate was higher for semi-coke than petroleum coke.
Review
Energy & Fuels
Ben Wang, Wei Li, Chuan Ma, Wu Yang, Deepak Pudasainee, Rajender Gupta, Lushi Sun
Summary: This paper summarizes the synergistic effects of co-gasification of petroleum coke (PC) with various carbon-based feedstocks on gasification reactivity, syngas production, and mineral transformation. The key parameters and approaches affecting the synergy are discussed, and the two main synergy mechanisms are explored. Suggestions for improving syngas quality and dealing with emerging feedstocks are provided.
JOURNAL OF THE ENERGY INSTITUTE
(2022)
Article
Engineering, Environmental
Tianxu Shen, Jingcun Yan, Xiao Zhu, Lulu Wang, Laihong Shen
Summary: MFB-TGA is a micro fluidized bed thermogravimetric analysis technique with high accuracy and stability, which has the potential for extensive application in evaluating catalytic combustion and deducing oxidation mechanisms, oxygen migration pathways, and combustion kinetics. The measurement stability of MFB-TGA is influenced by various factors such as temperature distribution and gas disturbance.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Chemical
Haigang Zhang, Zhongjie Shen, Jianhong Gong, Haifeng Liu
Summary: This study investigates the regeneration reaction of spent fluidized catalytic cracking catalyst (SFCC) at different atmospheres. The results show that regeneration in air effectively removes coke on the catalyst surface but has a poor effect on eliminating coke inside micropores. Regeneration in O2/CO2 atmosphere has a good effect on recovering pore structure and activity. Regeneration in pure CO2 has a low conversion rate.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Energy & Fuels
Sanjun Wu, Shihui Wang, Zhenshan Li
Summary: The study developed a micro-fluidized bed integrated with thermogravimetry-mass spectrometry (MFB-TG-MS) to evaluate the combustion kinetics of biomass char in the fluidized state. The MFB-TG-MS system reported herein allows for effective measurements of the rapid combustion kinetics closer to the intrinsic kinetics inside a fluidized bed reactor. A genetic algorithm was employed to optimize certain combustion kinetic parameters. This study provides valuable insights into the kinetics of biomass char combustion.
Article
Engineering, Environmental
Qiang Lu, Rui Guo, Hang Zhang, Jie-Ping Wang, Ting Lu, Guang-Yue Li, Ying-Hua Liang
Summary: This study investigates the catalytic mechanism of sodium in coke gasification through a combination of experimental and theoretical methods. The results show that sodium not only reduces the activation energy for initial carbon layer oxidation, but also inhibits carbon matrix reconstruction, thereby promoting the production of CO molecules.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Chemical
Hao Wang, Youjun Lu
Summary: In this study, three-dimensional simulations were performed using the energy minimization multiscale (EMMS) model to investigate the voidage distribution and bed expansion in supercritical water fluidized beds (SCWFBs). The experimental results validated the accuracy of the EMMS model, and the simulation results can provide theoretical guidance for the scaled-up design of SCWFBs.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Energy & Fuels
Chen Liang, Xiaofang Wang, Qinggang Lyu
Summary: Using oxygen and steam as gasifying agent in a Circulating Fluidized Bed (CFB) preheater can enhance the gasification reactivity of coal; replacing air by O-2-steam in the gasifying agent and controlling the modification temperature and steam to coal ratio can improve the gasification reactivity of modified char; the gasification reactivity of modified char increases and then decreases with the highest value at a steam to coal ratio of 0.87.
Article
Energy & Fuels
Hao Song, Haiping Yang, Chuang Zhao, Junhao Hu, Jun Zou, Peng Wu, Siqin Li, Hanping Chen
Summary: This study investigates the co-gasification and catalytic co-gasification of petroleum coke and coal at high temperatures. It compares the structural characteristics of high temperature petroleum coke and bituminous coal pyrolysis char, explores the effects of blending ratio on gasification reactivity and synergy, and studies the impact of catalyst on co-gasification. The results show that the gasification reactivity of the blends increases with the coal blending ratio, and a synergistic effect is observed as the co-gasification proceeds with temperature.
Article
Energy & Fuels
Yang Xu, Guangqian Luo, Mengli Zhou, Qingzhu Zhang, Zehua Li, Shibo Zhang
Summary: This study investigated the use of NFM as a cost-effective sorbent for Hg-0 removal from flue gas, showing that untreated NFM had high efficiency over a broad temperature range, while calcination process might have negative effects on its performance. The research also revealed the Hg-0 removal mechanism and demonstrated the dominance of chemisorption in the process.
Article
Engineering, Environmental
Yang Xu, Guangqian Luo, Qingzhu Zhang, Wei Cui, Zehua Li, Shibo Zhang
Summary: Novel waste-derived sorbents synthesized through one-step co-pyrolysis of wood and PVC have shown good stability in Hg and halogens removal, with Fe doping further enhancing the stability. Kinetic analysis revealed different rate-limiting steps before and after Fe doping, and water-washing pretreatment can remove loosely-bonded halogens while retaining essential halogens for Hg removal.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Environmental
Xiaoyu Li, Juan Chen, Yi Xiao, Shouyan Chen, Chunmei Lu, Guangqian Luo, Hong Yao
Summary: Combining quantum chemistry, kinetic simulations, and DTF experiments, the research revealed the transformation behavior of chromium under oxy-coal combustion in the presence of steam and HCl. It was found that HCl promoted the oxidation of chromium to hexavalent CrO2Cl2, while the coexistence of HCl and steam divided the transition of chromium into two stages, ultimately leading to the formation of CrO2Cl2 as the predominant species. The introduction of HCl into the combustion atmosphere induced more chromium release, and the presence of steam reinforced the effect of HCl on chromium transformation.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Energy & Fuels
Yang Xu, Guangqian Luo, Qingzhu Zhang, Zehua Li, Shibo Zhang, Wei Cui
Summary: Sulfurized chars derived from wood and scrap tire pyrolysis were developed as cost-effective sorbents for capturing elemental mercury (Hg-0) from flue gas. The synergistic effect between wood and tire during co-pyrolysis enhanced the Hg-0 capture capability of the sulfurized chars. Chemisorption dominated the Hg-0 removal process, with organic sulfur/elemental sulfur serving as active components for Hg-0 oxidization into HgS.
Article
Chemistry, Multidisciplinary
Zehua Li, Renjie Zou, Yang Xu, Liang Cao, Guangqian Luo, Hong Yao
Summary: The study utilized a self-designed micro fluidized bed reactor and an online char particle sampling system to investigate the kinetics of coal char combustion and gasification. It was found that the reactivity of sampled char in oxy-fuel combustion followed a specific trend with sampling time, while the gasification reactivity increased gradually with sampling time.
Article
Energy & Fuels
Zehua Li, Renjie Zou, Yang Xu, Guangqian Luo, Hong Yao
Summary: This study reported a novel microfluidized bed reactor combined with a solid char particle online sampling system to investigate the effect of CO2/H2O on semi-char properties and reactivity. The results showed that the activation energy of the semi-char increases during oxy-steam combustion, and the reactivity of the semi-char is higher than that of the original coal char in the early combustion stage, with H2O having a greater influence on semi-char reactivity compared to CO2.
Article
Engineering, Environmental
Mengli Zhou, Yang Xu, Guangqian Luo, Qingzhu Zhang, Lin Du, Xiaowei Cui, Zehua Li
Summary: Phosphorus-doped biochars (PBCs) derived from one-step pyrolysis of H3PO4-laden biomass showed improved mercury removal efficiency and surface area. The chemisorption mechanism involving electron transfer was responsible for the enhanced Hg-0 oxidation.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Thermodynamics
Zehua Li, Renjie Zou, Yang Xu, Yuan Fang, Guangqian Luo, Hong Yao
Summary: In this study, coal chars with different cooling rates were prepared and characterized, showing that carbon structure tends to be graphitized during cooling and in-situ char has the lowest carbon graphitization. The reactivity of chars decreases with cooling rate, with in-situ char having the highest carbon defects and most active surface area.
COMBUSTION AND FLAME
(2022)
Article
Engineering, Chemical
Can Fang, Renjie Zou, Guangqian Luo, Chengshuai Li, Min Lv, Li Wang, Haoyu Zhang, Hong Yao
Summary: A coupled demister with directing and perforated plate was proposed for fine droplets removal in the MSF desalination process. The performance was evaluated and the results showed that the main influencing factors were the length of the directing plate, the installation angle, and position. A coupled mist eliminator was designed to improve the removal efficiency, and it showed the best performance compared to others.
Article
Materials Science, Multidisciplinary
Ruihuan Cheng, Xingchen Shen, Stefan Klotz, Zezhu Zeng, Zehua Li, Alexandre Ivanov, Yu Xiao, Li-Dong Zhao, Frank Weber, Yue Chen
Summary: In this study, the high-pressure lattice dynamics of PbTe were investigated using molecular dynamics simulations. The results show that the transverse-optical mode and the frequency of the transverse-acoustic phonon exhibit non-monotonic pressure dependence under high pressure. The theoretical predictions were compared with experimental data, and the phonon transport mechanisms were revealed by calculating the pressure-dependent lattice thermal conductivity.
Article
Materials Science, Multidisciplinary
Zehua Li, Shasha Li, John-Paul Castellan, Rolf Heid, Yu Xiao, Li-Dong Zhao, Yue Chen, Frank Weber
Summary: This study investigates the soft transverse optic phonon mode in SnTe compared to PbTe using inelastic neutron scattering and ab initio lattice dynamical calculations. The calculations predict that the soft mode in SnTe has a strongly asymmetric spectral weight distribution similar to PbTe, contrary to previous reports. Experimentally, the overall width of the phonon peaks in the neutron scattering spectra is found to be comparable in SnTe and PbTe.
