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Science China(Technological Sciences) 2011年第7期54卷 1680-1683页

作者： DoMan JEON TaeJin KANG HyungTaek KIM SiHyun LEE SangDo KIM Division of Energy Systems Research Ajou University Korea Institute of Energy Research DaeJeon Republic of Korea

Lignite is a low rank coal which is evenly distributed throughout the world and accounts for 45% of the total coal reserves. As it has a higher moisture content, its moisture content must be reduced in order to utilize it in power plant. In the present work, experiments on lignite has been done using a lab scale fluidized-bed reactor. Drying lignite through fluidized-bed reactor has a higher drying rate because there is good contact between particles and gas in the fluidized-bed reactor. Fluidized-bed drying can use air of 1.5 times of the minimum fluidizing velocity performance at bubbling fluidized-bed. Experiments have been performed on coal particle sizes of 0.3-1 mm, 1-1.18 mm and 1.18-2.8 mm, with operating temperatures being 100℃, 125℃ and 150℃, respectively. It is found that fluidization has a higher drying rate due to the heat transfer rate through air velocity. Hence, moisture content in lignite can be dried to a desired value with a time interval of 10 rain. The experiment through fluidized-bed reactor is expected to be useful for saving money and time.

关键词： low rank coal moisture content minimum fluidizing velocity bubbling fluidized-bed

Carbon monoxide adsorptive capability of low rank coal's maceral

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Journal of coal Science & Engineering(China) 2008年第4期14卷 678-682页

作者：王月红郭立稳张九零 School of Resource & Safety Engineering China University of Mining & Technology(Beijing)Beijing 100083China School of Resource & Environment Hebei Polytechnic UniversityTangshan 063009China

The centrifugal separation with gravity experiment was made for getting every pure macerals like inertinite and vitrinite,and the isothermal adsorption tests of pure mac- eral are carried out at 30,40,50,55,60,65℃,respectively,after analyzing the proximate element and maceral of coal samples,which was aimed to study the CO adsorptive capa- bility of every maceral of low rank coal at difference temperature and *** results show that the adsorption isotherm of CO can be described by Langmuir equation because it belongs to the Type I adsorption isotherm at low temperature(T≤50℃),and the tem- perature effect on coal adsorption is greater than of pressure in lower temperature and pressure area;what's more,the relationship is linear between the coal adsorption quantity of CO and the pressure at high temperature(T>50℃),it can be described by Henry equation(Q=KP),which increases with *** temperature and pressure has great influence on CO adsorptive capability of low rank coals,especially the temperature's effect is so very complex that the mechanism need to study *** the same time,the volatile matter,inertinite,oxygen-function groups and negative functional groups are high popu- larly in low rank coal samples,especially,the content of hydroxide(-OH) has great influ- ence on CO adsorption in that the inertinite has stronger effect than vitrinite on adsorptive capability of low rank coal samples,the result is same to the research on CH4 adsorption.

关键词： low rank coal CO maceral adsorption isotherm spontaneous combustion

Mechanism of oxidation of low rank coal by nitric acid

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Journal of coal Science & Engineering(China) 2012年第4期18卷 396-399页

作者： SHI Kai-yi TAO Xiu-xiang HONG Fen-fen HE Huan JI Yong-hua LI Ji-lan Department of Chemistry and Chemical Engineering Liupanshui Normal UniversityLiupanshui 553004China School of Chemical Engineering and Technology China University of Mining&TechnologyXuzhou 221008China

The pretreatment of low rank coal with nitric acid oxidation can promote its bio-liquefaction. However, the detailed mechanism of which remains an unresolved problem. In the present work, the characteristics of Fushun coal before and after oxidation by nitric acid were investigated combined with elemental composition, pore volume and pore size, Zeta potential, FT-IR, and 13C solid NMR spectrum analysis. The results show that the inorganic substance inlaid in coal are dissolved by ni- tric acid, which results in the decrease of coal ash content and increase of pore volume and pore size. Furthermore, there exist obvious chemical reactions between nitric acid and the functional groups of coal including aromatic ring carboxylation, side chain alkyl of aromatic ring oxidation and aromatic ring nitration. Among these reactions, some led to the increase in content of carboxyl, aliphatic carbon connected with O and humic acid carbon, while others caused the reduction of aromaticity, methyl carbon, substituted aryl carbon and side chain.

关键词： oxidation low rank coal nitric acid mechanism

Influence of heating rate on reactivity and surface chemistry of chars derived from pyrolysis of two Chinese low rank coals

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International Journal of Mining Science and Technology 2018年第4期28卷 610-616页

作者： Liang Dingcheng Xie Qiang Li Guangsheng Cao Junya Zhang Jun School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing)

A series of char samples were derived from pyrolysis of two typical low-rank coals in China （Shengli lig- nite and Shenmu bituminous coal） at low, medium and fast heating rates, respectively, to the same pyrol- ysis temperature 750℃. Then these chars were characterized by means of thermogravimetric analysis and Fourier transform infrared spectrometer with the aim to investigate the influence of heating rate in pyrolysis process on gasification reactivity and surface chemistry of them. Besides, a homogeneous model was used to quantitatively analyze the activation energy of gasification reaction. The results reveal that Shengli lignite and its derived chars behave higher gasification reactivity and have less content of oxygen functional groups than Shenmu coal and chars. Meanwhile, chars derived from Shengli lignite at 50℃/min and Shenmu coal at 200℃/min have the greatest gasification reactivity, respectively. The oxygen functional groups in Shengli lignite are easily thermo-decomposed, and they are less affected by the heating rate, while that in Shenmu coal have a significant change with the variation of heating rate. In addition, there is no good correlation between the change of oxygen functional groups and that of the gasification reactivity of the derived chars from pyrolysis at different heating rates.

关键词： Pyrolysis low rank coal Heating rateReactivity Kinetic parameter Surface chemistry

coalbed methane enrichment model of low-rank coals in multi-coals superimposed regions: a case study in the middle section of southern Junggar Basin

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Frontiers of Earth Science 2021年第2期15卷 256-271页

作者： Haihai HOU Guodong LIANG Longyi SHAO Yue TANG Guangyuan MU College of Mining Liaoning Technical UniversityFuxin 123000China College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China Oil&Gas Resource Survey Center China Geological SurveyMinistry of Land and ResourceBeijing 100029China

The Middle Jurassic Xishanyao Formation in the central section of the southern Junggar Basin has substantial amounts of low-ranked coalbed methane(CBM)recourses and is typically characterized by multi superimposed coal *** establish the CBM enrichment model,a series of experimental and testing methods were adopted,including coal maceral observation,proximate analysis,low temperature nitrogen adsorption(LTNA),methane carbon isotope determination,porosity/permeability simulation caused by overburden,and gas content *** controlling effect of sedimentary environment,geological tectonic,and hydrogeological condition on gas content was analyzed in *** results demonstrate that the areas with higher gas content(an average of 8.57 m3/t)are mainly located in the Urumqi River-Santun River(eastern study area),whereas gas content(an average of 3.92 m3/t)in the Manasi River-Taxi River(western study area)is relatively *** of the combined effects of strata temperature and pressure,the gas content in coal seam first increases and then decreases with increasing buried depth,and the critical depth of the inflection point ranges from 600 m to 850 *** by the changes in topography and water head height,the direction of groundwater migration is predicted from south to north and from west to *** on the gas content variation,the lower and middle parts of the Xishanyao Formation can be divided into three independent coalbearing gas *** a single gas-bearing system,there is a positive correlation between gas content and strata pressure,and the key mudstone layers separating each gas-bearing system are usually developed at the end of each highstand system *** new CBM accumulation model of the multi-coals mixed genetic gas shows that both biological and thermal origins are found in a buried depth interval between 600 m and 850 m,suggesting that the coals with those depths are the CBM enrichment horizons and favorable exploration regions

关键词： Xishanyao Formation multi-coal seams superimposed region low rank coal main controlling factors enrichment model

Effect of the benzene ring of the dispersant on the rheological characteristics of coal-water slurry:Experiments and theoretical calculations

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International Journal of Mining Science and Technology 2021年第3期31卷 515-521页

作者： Lin Li Chuandong Ma Shanpei Hu Meng He Hao Yu Qingbiao Wang Xiaoqiang Cao Xiaofang You College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China College of Safety and Environment Engineering Shandong University of Science and TechnologyQingdao 266590China National Engineering Laboratory for coalmine Backfilling Mining Shandong University of Science and TechnologyTai’an 271019China Department of Resource and Civil Engineering Shandong University of Science and TechnologyTai’an 271019China

In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents,so as to explore the influence of benzene ring on the performance of *** results of the LCWS preparation experiments revealed that the pulp-forming performance of PDPE exceeded that of *** LCWS concentration is 62%,64%,and 66%,the apparent viscosity corresponding to PDPE is 247.80,504.17,and 653.10 mPa·s,and the apparent viscosity corresponding to PLE is 548.10,1470.61,and 1549.98 mPa·s,*** C_(1000)(When the apparent viscosity is 1000 mPa·s,the corresponding concentration of LCWS is defined as C_(1000))values of PDPE and PLE are 67.60%and 62.95%,*** addition to the van der Waals forces and hydrogen bonds between the PDPE and/or PLE molecules and coal,the benzene rings of PDPE presentπ-πstacking effect with the aromatic rings of *** could facilitate and strengthen the adsorption of PDPE on coal,which would be conducive to further improving the dispersion of coal *** two dispersants have no significant difference in effect on the pyrolysis of *** simulation results indicated that the times for PDPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps,*** self-diffusion coefficient(D)of the PDPE and PLE on coal is 3.16 x 10^(-6)and6.57×10^(-6)m~2/s,respectively,and their interaction energies with coal are 785.71 and 648.60 kcal/mol,*** results of the simulation calculations demonstrated that PDPE adsorbed on coal easier than PLE,and its binding is more stable than that of PLE owing to theπ-πstacking effect,which is conducive to uniform dispersion of coal in *** simulation results confirmed the experimental results.

关键词： low rank coal low-rank coal-water slurry Benzene ring Molecular dynamics simulation

Blended coals for improved coal water slurries

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Journal of China University of Mining and Technology 2008年第1期18卷 50-54页

作者： GU Tian-ye WU Guo-guang LI Qi-hui SUN Zhi-qiang ZENG Fang WANG Guang-you MENG Xian-liang School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Three coal samples of different ranks were used to study the effect of coal blending on the preparation of coal Water Slurry (CWS). The results show that by taking advantage of two kinds of coal, the coal concentration in slurry made from hard-to-pulp coal can be effectively improved and increased by 3%–5% generally. DLT coal (DaLiuTa coal mine) is very poor in slurryability and the stability and rheology of the resulting slurry are not very good. When the amount of easily slurried coal is more than 30%, all properties of the CWS improve and the CWS meets the requirements for use as fuel. coalification, porosity, surface oxygenic functional groups, zeta potential and grindability have a great effect on the performance of blended coal CWS. This leads to some differences in performance between the slurry made from a single coal and slurry made from blended coal.

关键词： low rank coal coal water slurry coal blending slurryability zeta potential

Cation exchange for mercury and cadmium of xanthated,sulfonated,activated and non-treated subbituminous coal,commercial activated carbon and commercial synthetic resin:effect of pre-oxidation on xanthation of subbituminous coal

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International Journal of coal Science & Technology 2014年第2期1卷 235-240页

作者： Lewis M.Gomez Fredy Colpas-Castillo Roberto Fernandez-Maestre Department of Electrical Engineering and Department of Chemistry University of Southern CaliforniaLos Angeles 90089USA Grupo de Carboquı´mica Programa de Quı´micaUniversidad de CartagenaCampus de San PabloCartagenaColombia

A subbituminous coal was oxidized with air at 150℃on a fixed bed for 4 h and xanthated with carbondisulfide in a basic solution,at 30 or 5-10℃.This xanthated coal was evaluated for the removal of Hg^(2+)and Cd^(2+)from 7,000 mg/L aqueous solutions;metal concentrations were detemmined by atomic absorption *** ionexchange of the xanthated coal was compared against those of the original subbituminous coal,a sulfonated subbituminouscoal,activated carbon,commercial activated carbon,and commercial synthetic *** commercial synthetic resinshowed the highest exchange capacity(concentration factor 98%)followed by the xanthated coal(concentration factor 96%).The retention of cadmium on the sulfonated subbituminous coal was lower(exchange capacity 0.56 meq/g)thanthat of xanthated coals(1.85±0.09 meq/g).Our xanthated coal showed a better Cd^(2+)removal(8l%o against 15%)than anon preoxidized 40-h-xanthated coal,which shows that oxidation of coal increased the amount of oxygenated groups whichenhanced xanthation.

关键词： lon exchange Heavy metals Adsorption low rank coal Xanthated coal