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Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current gasification mechanism model has large residuals under variable working conditions and the model can only simulate one working condition in a single run and cannot be run continuously to characterize the long-cycle operation of gasifier. This paper firstly used the process simulation software Unisim to establish the long-cycle mechanism model of gasifier based on the reaction kinetics of 3000 t/d coal-water slurry gasifier in Yulin Chemical Co. of National Energy Investment Group. Then, a hybrid model of the mechanism model in parallel with the BP neural network model was developed, and the simulation accuracy of the hybrid model was verified and analyzed. Finally, the application of the hybrid model in gasification index prediction and gasification performance analysis was investigated. The application of the hybrid model for gasification index prediction and gasification performance analysis was investigated. The results show that the simulation error of the single-case mechanistic model for gasification temperature and syngas composition is less than 5%. The long-period mechanistic model can predict the variation trend of gasification furnace temperature, and the correlation coefficient between the simulated and operational values is 0.822, but the simulated values fluctuate greatly, and the relative standard deviation (RSD) of the simulated gasification temperature values is 3.8 times of the operational values. The simulation accuracy of the hybrid model for gasification is significantly better than that of the mechanistic model. The simulation accuracy of the gasification mixing model is significantly better than that of the mechanistic model, with the simulated values matching well with the trend of the operating values, and the errors of gasification temperature and syngas composition are less than 2%. The mixing model still has a high accuracy after the change of working conditions, and the simulation error increases from 2% to less than 4%. As the oxygen to coal ratio increases from 480 Nm3/m3 to 498 Nm3/m3, the gasification temperature calculated by the mixing model increases from 1160 ℃ to 1306 ℃, the CO2 content in the syngas increases from 18.6% to 19.9%, the CO content decreases from 42.6% to 42%, and the H2 content decreases from 37.7% to 36.8%, which are consistent with the mechanistic model. The hybrid model has a significant correction effect on the mechanistic model, in which the temperature is corrected by about 38 ℃, and X(CO), X(CO2) and X(H2) are corrected by −1, −0.9 and 1.5 percentage points respectively.

Carbon emission from the coal-burning power plant is the main source of CO2 emitted in the China’s energy industry. Biomass power generation is deemed to be a carbon-neutral or even carbon-negative mode. Therefore, the development of coal coupled biomass gasification technology for power generation can help to achieve a coal substitution and carbon emission reduction and is a realistic and feasible path for maintaining a low-carbon coal power generation. In this context, an overview of three coal coupled biomass power generation technologies (the coal/biomass direct combustion of coal and biomass, the coal/biomass direct combustion coupled in parallel mode, and the coal direct combustion coupled with biomass gasification) has been conducted in this study. The characteristics of the above three technologies have been analyzed. Future development trends in the coal-burning coupled biomass gasification power generation technology have been put forward. The physicochemical adaptability of the feedstock and the influence of the feedstock on the gasifier are also studied based on the coupled gasification power generation technology. This work has emphasized the technological process of coal coupled biomass gasification power generation technology, including biomass transportation system, gasifiers (the technical characteristics, technical challenges and development direction of circulating fluidized bed gasifier (CFB), double fluidized bed gasifier (DFB), downdraft fixed bed gasifier, updraft fixed bed gasifier, crossdraft fixed bed gasifier and chain grate have been analyzed), gas cooling system, gas-pressurized transportation system, combustion system and gas purification system. The energy utilization efficiency analysis, economic analysis and environmental benefit analysis of the technology have been carried out. The analysis obtained would provide a theoretical reference and technical support for the research and application of coal-coupled biomass power generation technology. In addition, a series of national policies to promote coal coupled biomass gasification power generation technology and the current successful cases of coal coupled biomass gasification power stations are also presented. Finally, the challenges and future development of coal coupled biomass power generation technology have been prospected.

Lignocellulosic biomass is a clean and renewable energy source due to its abundance, wide distribution, and CO2 neutrality. Biomass gasification technology can convert the biomass into producer gas which can be used as clean fuels in boiler or engine for heating and electricity supply. It is of great important to achieve the goal of “carbon neutrality” and “emission peak” in China. However, the lignocellulosic biomass has the major drawback of high content of water, high content of oxygen element, and low heating value, resulting in a lower gasification efficiency and higher content of tar. Torrefaction pretreatment can effectively upgrade biomass into high-grade fuels with a lower content of oxygen element and higher energy density. First, the torrefaction pretreatment was employed to improve the quality of maize straw at different torrefaction temperatures (200, 220, 240, 260, 280 and 300 ℃). The properties of the raw and torrefied maize straw was analyzed by the ultimate analysis, proximate analysis, X-Ray diffractometer, Fourier transform infrared spectrometer, and thermo gravimetric analyzer. Then, the torrefied maize straw was gasified in a home-made small-scale fixed-bed gasification reactor. The effect of torrefaction temperature on the properties of gasified products (producer gas, char, and tar) was investigated. Results showed that the contents of oxygen element and volatiles gradually decreased with the increase of torrefaction temperature from 200 to 300 ℃, while the contents of carbon element and fixed carbon increased, resulting in an increase of the calorific value from 17.26 MJ/kg to 25.50 MJ/kg. With the increase of torrefaction temperature, the mass yield of producer gas decreased, while the H2 content in producer gas increased from 13.85% to 22.56%. The highest lower-heating-value (LHV) of producer gas was 9.36 MJ/Nm3, achieving at the torrefaction temperature of 220 ℃. Higher torrefaction temperature resulted in a higher mass yield of bio-char. In addition, the contents of carbon element and fixed carbon increased with the increase of torrefaction temperature, while the volatile fraction and ash decreased, and the calorific value increased from 22.74 MJ/kg to 24.52 MJ/kg. Higher torrefaction temperature resulted in a lower mass yield of tar. The tar was mainly composed of aromatics, phenols, and aliphatic hydrocarbons, among which the relative content of aromatics and phenols is much higher than that of aliphatic hydrocarbons. With the increase in torrefaction temperature, the content of aromatics first increased, and then decreased, while the content of phenols first decreased and then increased. Therefore, the torrefaction pretreatment is a well-established approach to improve the quality of biomass by removing oxygen element. In addition, the gasification performance of biomass is also improved after torrefaction pretreatment, resulting in an increase of the LHV of producer gas and the reduction of the yield of tar.

The biomass chemical looping gasification process involves various complex reaction processes, including pyrolysis, gasification, and reforming, which occur within the same reaction space. These reactions exhibit intricate interactions, posing challenges for achieving targeted control. Consequently, some issues arise, such as low carbon conversion, high tar yield, and difficulties in attaining auto thermal operation. The biomass pyrolysis chemical looping re-forming process, employing the decoupling strategy, aims to achieve an independent regulation of pyrolysis and reforming reactions, thereby mitigating the issues mentioned above. The process underwent simulation using the Aspen Plus software, and the model’s validity was confirmed by comparing it with the results of pyrolysis experiments. Using the established process model, the impact of pyrolysis reactor temperature, fuel reactor temperature, and steam-to-biomass mass ratio on process performance was examined. The results demonstrate the effective predictive capability of the established process model regarding the distribution of pyrolysis products within the temperature range of 400−600 ℃. As the pyrolysis temperature rises, the syngas yield exhibits a generally increasing trend, reaching its peak at 550 ℃ with a value of 1158.98 Nm3/kg biomass. At a pyrolysis temperature of 600 ℃, the heat demand of the reforming reactor is adequately met by the exothermic reactions of pyrolysis char and oxygen carrier oxidation without any surplus energy. Elevating the fuel reactor temperature augments the syngas yield but diminishes the H2-to-CO ratio and energy efficiency of the syngas while also necessitating a substantial increase in the circulation rate of bed material for achieving auto thermal operation. Steam serves as an effective regulator for controlling the H2-to-CO ratio in syngas. The pyrolysis chemical looping reforming process generates syngas with an H2-to-CO ratio of 2.0 when the steam-to-biomass mass ratio is 0.45, lower than the ratio needed for the biomass chemical looping gasification process. Consequently, taking into account the syngas yield and process performance, the recommended operating conditions for the pyrolysis chemical looping reforming process are as follows: a pyrolysis reactor temperature ranging from 550 to 600 ℃, a fuel reactor temperature of 700 ℃, and a steam-to-biomass mass ratio of 0.45.

Potassium (K) is a major inorganic element in biomass. The transformation of K during biomass gasification can cause slagging, ash deposition and agglomeration problems. The addition of coal ash rich in Si and Al is one of the effective methods to solve these problems. In most biomass, K mainly exists in the form of water-soluble inorganic salts, such as K2CO3, K2SO4 and KCl. However, the content of these K salts varies significantly with the species of biomass, which leads to the significant differences in the agglomeration and slagging behaviors during gasification. Therefore, the research utilized pine wood doped with K2CO3, K2SO4 and KCl to simulate different types of inorganic K in biomass. The effect of coal ash on the agglomeration in the fluidized-bed reactors (silica sand as the bed material) and the transformation of different types of inorganic K in biomass was studied systematically during steam and CO2 gasification. Although two kinds of coal ash with different mineral compositions were used, the K2CO3-doped and K2SO4-doped pine wood react with both kinds of ash to form kaliophilite (KAlSiO4) during gasification. However, under the CO2 atmosphere, for the KCl-doped pine wood, most of KCl is mainly retained by physical adsorption because the ability to form KAlSiO4 is weaker than that under the steam atmosphere, which results in a lower K retention ratio under the CO2 atmosphere. In addition, the K retention ratio of KCl-doped pine wood is significantly lower than that of pine wood loaded with K2CO3 and K2SO4, which suggests that KCl in biomass tends to release and reacts with coal ash only to a limited extent. Therefore, KCl in biomass is more likely to cause ash deposition or corrosion problems. However, the results of thermodynamic equilibrium calculations indicate that the reaction between the three types of K salts and coal ash mainly forms leucite or feldspar, which are significantly different from the experimental results. Lastly, although the addition of coal ash cannot stop the formation of agglomerates, it inhibits the formation process of low melting-point K silicates generated from the reaction between silica sand and K-salt-doped pine wood. Also, coal ash makes the agglomerates to be broken more easily, thus mitigating the agglomeration problem in fluidized-bed reactors effectively.

Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The research status of traditional gasification technology for hydrogen production from organic solid waste are reviewed, the influence of three main factors, gasification medium, gasification temperature and catalyst, on hydrogen production effect is analyzed in detail, by analyzing the action mechanism and summarizing the advantages and disadvantages in the application process, the technical disadvantages of this technology are put forward purposefully, it is pointed out that the technology should be developed from four aspects: mechanistic exploration, development of high-performance composite catalyst/catalyst with special structure, development of hydrogen production technology by co gasification with coal, and coupling with other new gasification hydrogen production technologies in the future, so as to better promote the industrial application of the technology. [ABSTRACT FROM AUTHOR]

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Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The excessive utilization of fossil fuels has caused the energy crisis and greenhouse effect, and the development of clean and sustainable sources can adjust the energy structure of China and promote green and sustainable development. Hydrogen, as a promising energy source and a clean fuel with no harm to the environment, has become the most promising energy carrier in future energy. Therefore, it is necessary to seek green and sustainable hydrogen production technologies with low energy consumption and low cost. Under the background of "double carbon" , hydrogen production from biomass is considered as a green and sustainable development technology, which is deemed to have long-term growth potential and is expected to gradually reduce environmental pollution and over-exploitation of resources. In view of the current research trends and emerging technologies, this paper focuses on the review of the principles, influencing factors and current research status of hydrogen production technologies from thermochemical conversion of biomass to pyrolysis, steam gasification, supercritical water gasification and chemical looping hydrogen production, and provides an outlook on the future development of current technologies.

The biochemical sludge was mixed with coal-water slurry to prepare the slurry. The effect of the biochemical sludge on slurry performance and gasification performance was investigated through the analysis and research of the additive amount, slurry concentration, rheological properties, water separation rate and gasification simulation calculation. The results showed that the maximum addition amount of biochemical sludge is 10% under the condition of constant slurry concentration, and it was necessary to increase the amount of additives to maintain the slurry performance; the slurry with 10% biochemical sludge can be used for the gasification process to produce syngas, the total dry gas volume during gasification decreased by about 4.8%, the effective gas content decreased by about 1.2%,the specific oxygen consumption was basically unchanged, and the raw material consumption increased by about 6.6% . [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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In order to control the spontaneous fire in the goaf, CO2 is used to study the prevention and control of the spontaneous fire in the coal mine. Combined with the actual situation of the spontaneous fire in the goaf at the back of the 150201 fully mechanized top coal caving face, this paper expounds the performance parameters and technical process of the relevant equipment of the large flow gaseous CO2 fire prevention and extinguishing system, and calculates the appropriate air volume of the working face, as well as the air injection volume, air injection intensity, air injection mode and air injection pressure in the goaf, which is the large flow gaseous. The results show that: the large flow gaseous CO2 fire-fighting system has a large gas production, which can fully meet the requirements of coal mine underground goaf fire-fighting work; the technological parameters of CO2 gas injection are similar to those of N2 injection, and on the premise that the CO2 pipeline release port is located in the oxidation zone of goaf, no CO2 gas will flow from the working face; liquid CO2 is a by-product of chemical plant, with a relatively low cost, is advantageous in the coal mine underground fire prevention work promotion application.

Copyright of Biomass Chemical Engineering is the property of Editorial Office of Biomass Chemical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the characteristics of gasified tar components and realize their resource utilization, the effects of gasification medium and gasification temperature on aliphatic compounds, alicyclic compounds, heterocyclic compounds, aromatic compounds (mainly polycyclic aromatic hydrocarbons(PAHs)) and aromatic hydrocarbon derivatives in sludge gasification product tar were investigated in a solid waste fluidized bed facility. Results show that at 850°C, only under the condition of water vapor generated aliphatic compounds, the content of indene, biphenyl, fluorene and phenanthrene in aromatic compounds is the highest under the conditions of the water vapor. The content of nitrile compounds in aromatic hydrocarbon derivatives is the highest under air conditions. Under the conditions of air and water vapor, aliphatic compounds is produced only in 700°C gasification, the contents of alicyclic compounds, nitriles, quinoline compounds in aromatic hydrocarbon derivatives are the highest in 750°C, the contents of indene, naphthalene compounds in aromatic compounds are the highest in 850°C. The heterocyclic compounds are mainly pyridine and 4,4'-bis(tetrahydrothiopyran), the contents of pyridine is the highest in 700°C, the contents of 4,4'-bis(tetrahydrothiopyran) is the highest in 800°C . [ABSTRACT FROM AUTHOR]

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In this paper, two TEKNA inductive plasma sphere systems with different powers were used to manufacture sphere tantalum powders. The influence of powder feeding rate on the powder sphere effect and manufacture efficiency was particularly analyzed. The results indicate that the selection of the powder feeding rate was related to factors both equipment power and powder flowability. On the condition of achieving good sphericity of tantalum powders, the manufacturing efficiency of 80 kW equipment was several times than that of 15 kW. The high-power equipment showed advantages not only on manufacture rate, but also on the sphere effect and manufacture yield. The elemental gasification and impurity cleaning mechanism in the sphere process w ere also discussed in this study. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biomass gasification is an efficient utilization way to produce high calorific value syngas via the chemical conversion of biomass in renewable energy. Most previous studies focused mainly on biomass gasification in small-scale fixed beds and fluidized beds. Therefore, it is necessary to explore the slagging characteristics in the large and medium-sized gasification equipment in recent years. In this study, a pilot-scale fluidized bed was selected to investigate biomass gasification using an infrared gasboard-3100p syngas analyzer. Taking the molded bark and corn stover as raw materials, the amount of feed and air supply was used to determine the effects of air equivalent ratio, gasification temperature, and air supply temperature on the gasification characteristics. The results are as follows. 1) A better effect was obtained in the fluidized-bed gasification of formed bark, compared with the corn stover. In formed bark syngas, the calorific value and gasification efficiency reached 5.66 MJ/m³ and 59.62%, respectively, when the feedstock was 40kg and the air equivalent ratio was 0.24. The hydrogen content of 11.2% was high in the syngas, due mainly to the high moisture content of formed bark (11.6%). In formed corn stover, the caloric value and gasification efficiency were 3.92 MJ/m³ and 33.92%, respectively, due possibly to low volatiles, the low fuel calorific value, and high ash content. The air equivalent ratio had an important influence on the gasification characteristics. The gasification effect of molded bark increased first and then decreased, with the increase of air equivalent ratio. Specifically, the low air equivalent ratio inhibited the gasification reaction, and the high air equivalent ratio promoted the oxidation reaction, where part of combustible gas was burned by oxygen. The optimum air equivalent ratio was around 0.24. 2) The high gasification temperature was a benefit to the gasification effect. In formed bark syngas, the heat value and gasification efficiency increased by 20.07% and 28.76%, respectively, at the gasification temperature from 700 ℃ to 800 ℃. The gasification effect was not significantly improved when the primary air temperature increased from 100 ℃ to 300 ℃. But the bottom temperature of the furnace increased by about 200 ℃, which affected the safety of the equipment. 3) Both kinds of biomass had obvious slagging phenomenon. Quartz sand particles were bonded together, and then the slag surface formed a molten glass state. The slagging compositions were mainly complex compounds, such as KAl(SiO3), K2MgSi5O12,and SiO2. The reason for the formation of slagging was that alkali metal elements, such as K and Mg, in biomass were enriched in quartz sand particles during the gasification process, and the molten salt with a low melting point was formed at high temperature to bond quartz sand particles into slag blocks. The ash rate of tree bark was three times higher than that of corn stover, although the content of K in corn stover ash was lower than that of tree bark. If the content of K was higher in the same amount of feed, it was easier to form compounds with lower melting points. Bark ash contained more Ca. CaSO4 with a high melting point was produced by Ca and S during gasification, which was not easy to melt to bond quartz sand particles, thus inhibiting slagging. These two reasons can lead to the more serious slagging of corn stover than that of tree bark during biomass gasification in a pilot-scale fluidized bed. [ABSTRACT FROM AUTHOR]

The pattern identification of the eight extraordinary meridians reflected in the book titled Lin Zheng Zhi Nan Yi An (Case Records as a Guide to Clinical Practice) includes the theories of six compartments of yin and yang"， "triple jiao" and u branch, root and center of six qi" in Huangdi Neijing，align with Ye TianshiJ s theory of udefense-qi-construction and blood" and "triple jiao'，- The common route of Taichong meridians is from the bottom to the top，or from the root of Shaoyin through Yangming to the top of Guangming, crossing three jiao and three compartments, supplied with defense, qi，nutrient and blood by all the meridians. The essential qi is thus vaporized upwards to the brain. The defensive qi of all zang-organs in the triple jiao diverges into two pathways: one outside the vessels, or defensive qi goes out of triple jiao and flows into six fu organs ； the other infusing into the vessels and converge at the extra meridians. The extra meridians are similar to lakes and rivers. They echo with the solitary organ of triple jiao. Interiorly，extra meridians unite the defense, qi，nutrient and blood，govern the three yin and three yang meridians to harmonize yin and yang, harmonize the essential qi and unite six qi; whereas exteriorly，triple jiao governs the defense，qi，fluids and humor，so as to balance heat and cold as well as yin and yang. When extra meridians and triple jiao are harmonious interiorly and exteriorly, yin-yang balance is achieved. By establishing the extra meridian system of Ye Tianshi? it can be used as reference to help us understand the physiology and pathology of traditional Chinese medicine， as well as predict，prevent，diagnosis and treatment of diseases. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the low efficiency of gasification at this stage，the technology of biomass gasification technology can solve it effectively． The method for process integration and combination can achieve higher process efficiencies，the quality and purity of gas will be better，and the investment costs will be lower ． The recently developed UNIQUE gasifier which integrates gasification，gas cleaning and conditioning in one reactor unit is an example for a promising process integration． Combine pyrolysis and gasification or gasification and combustion in single controlled stages． Poly-generation strategies for the production of multiple energy products offer high efficiency and flexibility．

The effect of different reaction temperature, reaction pressure and the ratio of water to lignite on the H2 production by gasification of lignite in supercritical water was investigated by using lignite as raw material and intermittent high temperature and high pressure reactor. Then, the catalytic effect of Fe powder and Ni powder with different mass fractions on the production of H2 was studied separately. The experimental results showed that the increase of reaction temperature could greatly improve the yield of H2. The suitable reaction temperature was 405 °C. The effect of reaction pressure on H2 production was not obvious, but the higher reaction pressure would slightly increase the yield of CH4, the appropriate reaction pressure was chosen as 23 MPa; higher ratio of water to lignite was conducive to the production of H2, but the cost would also increase, the appropriate ratio of water to lignite was selected as 10 : 1; the addition of metal catalyst Fe powder and Ni powder could significantly improve the yield of H2. When the mass fraction was low, the catalytic effect of Ni powder was better than that of Fe powder. When the mass fraction was higher, the catalytic effect of Fe powder was better. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper. NiO/TiO2 catalysts were prepared by coprecipitation, and their composition and morphology were characterized by means of XRD. XPS and SEM. Catalytic biomass gasification experiments were carried out using municipal solid waste as biomass raw material, NiO/titanium dioxide composite material and ICI46-1 catalyst as catalyst. The catalytic activity and service life of NiO/titanium dioxide catalyst and ICI46-1 catalyst were compared. The results show that the NiO/TiO2 composite material contained two phases of ana-tase TiO2 and NiO. whose morphology was nano-sphere, and the size of microsphere was about 1 pm. NiO was attached to the surface of TiO2 nano-flower in the form of nano-particles. This structure was beneficial to the increase of specific surface area and catalytic activity of NiO/TiO2 composites. The catalytic gasification test resulted show that the catalytic activity of NiO/TiO2 was obviously better than that of IGI46-1 catalyst. When the service life was 300 min. the gas yield of municipal solid waste pine wood gasification was 1.70 m3/kg (MSW), while the tar in gas was only 0.27 g/m3. When the service life reached 300 min, the activity of the catalyst remained above 98%, prolonging the service life of the catalyst. [ABSTRACT FROM AUTHOR]

With the development of the wood-processing industry, the artificial timber board is widely used for furniture, interior finishes, and wooden buildings. Due to the vast use of nitrogenous adhesives, the scrapped artificial timber board is named as nitrogen-rich wood waste, which has a great impact on environment. The gasification is one of the most important techniques for utilizing wood-based waste. Because of the clean and efficient characteristics, this technique can be used to dispose the nitrogen-rich wood waste. In order to study the gasification characteristics, gasification and pyrolysis of the nitrogen-rich wood waste and pine saw dust in Ar and Ar+O2 atmosphere were carried out in TG-MS-FTIR and the fixed bed, respectively. The effects of reaction conditions on the gasification-pyrolysis process and product distribution were studied. For the TG analysis, the experiments were carried out in Ar and Ar+O2 atmosphere, respectively. The reaction temperature increased from room temperature to 1 200 °C by a heating rate of 10 °C/min. The wave number region of FTIR was 400-4 000 cm-1, the working voltage of the mass spectrometer was 70 eV, and the mass-to-charge ratios were 16, 28, 44, 17, 27, 30, 43, and 46, respectively. In the fixed bed experiments, the reaction temperature was 750 °C and the reaction atmosphere of pyrolysis was Ar (Gasification: Ar+O2). The results showed that the TG and DTG curves of these two materials presented similar stage divisions. The DTG peak value of nitrogen-rich wood waste was about 70% of that of pine saw dust, although the temperature of peak value of nitrogen-rich wood waste appeared ahead 15-20 °C than that of pine saw dust, which was earlier than that of pine saw dust in the DTG curve. Furthermore, the DTG curve of nitrogen-rich wood waste possessed a shoulder peak at 280-300°C, but it can not be observed in the DTG curve of pine saw dust. In the experiments of TG-MS-FTIR and fixed bed, the compositions of main gas products were similar for these two feedstocks. However, the CH4 concentration of nitrogen-rich wood waste was much higher than that of pine saw dust during pyrolysis and gasification. More precisely, the CH4 concentration of nitrogen-rich wood waste was 48% higher than that of pine saw dust in the fixed bed gasification. These results suggested that the gasification of the nitrogen-rich wood waste had a better prospect of application. In addition, the nitrogen-rich wood waste generated much more gaseous nitrogen pollutants than pine saw dust. The NH3 concentration generated from the nitrogen-rich wood waste was about 147 times of that from pine saw dust. This indicated that gaseous nitrogen pollutants can be a barrier for the utilization of nitrogen-rich wood waste. In summary, the results from this study can be served as a constructive and meaningful reference for the treatment and high-efficiency utilization of nitrogen-rich wood waste. [ABSTRACT FROM AUTHOR]

In order to improve the catalytic activity, anti-carbon deposition and regeneration performance of dolomite catalyst which was easy to accumulate carbon and deactivate during biomass catalytic gasification, a fixed-bed suction gasifier test system was adopted in this study. Firstly, rod-shape particles were prepared from pine chips wastes using Fe-Dol-Ben (bentonite/limonite modified dolomite) as catalyst and fixed-bed downdraft gasifier as main body. An experimental system for biomass steam gasification was established. Then the high temperature steam catalytic gasification test was carried out with the above two raw materials. Finally, the effects of several factors on the catalytic gasification performance of pine wood and carbon deposition on the catalyst surface were studied. The factors affecting the catalytic gasification performance and carbon deposition on the catalyst surface were gasification temperature (temperature range is 700-1000 ℃), iron content (mass percentage range is 5%-20%) and the number of catalyst used (catalyst used number is 1-4). The results showed that the mass percentage of iron in FeDol-Ben catalyst was 15%, the gasification temperature was 900 ℃, and the volume fraction of hydrogen in gasification gas reaches the maximum of 58.38% under the condition that the mass ratio of steam to pine wood was 1. The results also showed that with the increasing of gasification temperature, the carbon deposition in FeDol-Ben catalyst decreased gradually, reaching the minimum value at 1 000 ℃, 80% lower than that at 700 ℃. In addition, the volume fraction of hydrogen in gasified gas increased first and then decreased with the increasing of iron content. At the same time, the carbon content decreased first and then increased, and the catalytic effect was better when the iron mass content was 15%. Under the same conditions as bentonite and pre-modified dolomite, the carbon deposition of Fe-Dol-Ben catalyst decreased by 80.6% and 53.6%, respectively. The experiment of catalyst regeneration and reuse showed that the crystal phase of the catalyst was basically the same as that of the pre-catalyst after the Fe-Dol-Ben catalyst regeneration at 700 ℃. The volume fraction of hydrogen in gasification gas decreased with the increasing of the number of times of regeneration, and the carbon deposition of the catalyst increased gradually. The results also showed that the volume fraction of hydrogen was still close to 50% after four times of catalytic gasification, which maintained the catalytic effect. In summary, considering the gasification effect, carbon deposition and economic factors, the optimization conditions were iron content of 15% and gasification temperature of 900 ℃. The study can provide reference for the development of bentonite/limonite modified dolomite catalyst and biomass high temperature steam catalytic gasification technology. [ABSTRACT FROM AUTHOR]

Large quantities of crop stalk resources are produced in China every year, and some of the stalks are incinerated, which pollutes the environment. Biomass gasification is attracting a great deal of attention as a way of utilizing biomass waste. In this study, a circulating fluidized bed experimental system was designed and constructed with a treating capacity of 150 kg/h, which equipped with secondary back-feeding device, steam generator and air preheater. The influences of secondary back-feeding device on the gasification performance were investigated with corn stalk after crushing and drying pretreatment as biomass feedstock. The effects of air equivalence ratio (ER) within 0.20～0.35 on gasifier temperature, tar content, gas composition, carbon conversion rate and gasification efficiency were investigated when the secondary back-feeding device was closed and open. The gasification reaction was promoted by increasing ER, and gasification efficiency and carbon conversion showed a trend of increasing firstly and then decreasing. The results showed that good gasification results were both obtained at ER of 0.26. When the secondary back-feeding device was closed, the maximum carbon conversion rate and gasification efficiency were 91.19% and 72.95%, respectively. Whereas the carbon conversion rate and gasification efficiency were higher when the secondary back-feeding device was open, which was up to 93.54% and 77.06%, respectively. The experimental results also showed that secondary back-feeding device had a good effect on tar cracking. When the secondary back-feeding device was closed and open, the tar content in gas was 7.5 g/Nm3 and 4.5 g/Nm3 at ER of 0.26, respectively, which meant that tar content can be decreased by 40% when secondary back-feeding system was open. The effects of steam/biomass ratio (S/B) on gasification characteristics were investigated when the secondary back-feeding device was open. The results showed that gas quality and gasification efficiency were improved with air as main gasifying agent and steam assisted. The better operation conditions of the corn stalk gasification were 0.26 of ER and 0.2 of S/B, and gas calorific value and gasification efficiency reached to maximum value of 5.89 MJ/3 and 81.45%, respectively. The results of tar distillation analysis under typical operating conditions indicated that the pyrolysis conversion of tar was promoted by increasing the reaction temperature of gasifier and maintaining a certain amount of water vapor in the gasifier. The experiment can provide reference for efficient and clean transformation and utilization of straw biomass. [ABSTRACT FROM AUTHOR]

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Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)