2018年02期目次

  • Construct and research advance in clean and cyclic utilizations of associated resources in high-alumina coal fly ash

    LI Huiquan;ZHANG Jianbo;WANG Chenye;LI Shaopeng;CAO Shaotao;HU Pengpeng;ZHU Ganyu;Key Laboratory of Green Process and Engineering,Institute of Process Engineering,Chinese Academy of Sciences;National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology;University of Chinese Academy of Sciences;

    High-alumina coal fly ash( HAFA) with high content of associated Al,Li and Ga is produced at a quantity of 30 Mt/a,however less than 30% of them is comprehensively utilized.It is a great challenge for the environment and ecology in the large coal and electricity production bases.To realize the utilization of HAFA into high value,this paper proposed the mechanical and chemical synergistic activation method to remove amorphous silica from HAFA efficiently.Based on this method,the desilicated HAFA was used to prepare the Al-Si composite,and the extraction of alumina using two-step-alkaline dissolution process was approved.The results shows that the mass ratio of Al_2O_3 to SiO_2 of HAFA increases from 1.75 to 2.75 after deep-desilication.After calcinations at 1 600 ℃ for 2 hours,the mullite phase content reaches up to 88.33%,and the product quality meets the high standard of industry.After the optimization of two-step-alkaline hydrothermal process,the highest extraction efficiency of alumina is 94. 9%. To utilize the associated Li and Ga from HAFA,Bayer process,a classic process applied in alumina industry is introduced in the extraction of alumina from HAFA. Accordingly,a circular economy system with multi industry chains is built,and it provides a new approach to the utilization of HAFA into high value products at a large scale.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 564K]

  • Clean and efficient utilization of lignite resources in China

    ZHAO Qi;Coal Chemistry Branch of China Coal Research Institute;State Key Laboratory of Coal Mining and Clean Utilization;National Energy Technology & Equipment Laboratory of Coal Utilization and Emission Control;

    For realizing the clean,efficient and high-value utilization of lignite resources,the distribution and coal characteristics of lignite resources in China were analyzed,and the main utilization methods were overviewed systematically. It is found that,the reserves of lignite resources in China are abundant and the regional distribution is concentrated.The lignite reserves in Inner Mongolia and Yunnan province possessed about 90% of the total lignite resources in China.The lignite in Inner Mongolia is older than that in Yunnan,the moisture,ash,sulfur content and wax content of lignite in Inner Mongolia are lower than lignite in Yunnan.Combustion is still the main method for lignite utilization.There are numerous chemical utilization technologies,while there is less industrial application except for the liquefaction in China.In the future,the research on lignite combustion technology should be enhanced to promote the clean and efficient development. The utilization of lignite chemical industry scientifically and accelerating the breakthrough of key barriers should be focused.The research of environmental protection technology and exploring the suitable environmental technology should be developed.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 113K]

  • Research progress on methanation catalyst research for synthetic natural gas from coal in fluidized bed

    ZHANG Yu;SONG Pengfei;HOU Jianguo;WANG Xiulin;GAO Zhen;YAO Huichao;MU Xiangyu;CNOOC Gas and Power Group Research & Development Center;

    Based on the main components of methanation catalysts for synthetic natural gas from coal in fixed bed and similar preparation technology of F-T synthesis fluidized bed,research status and development ideas of methanation catalyst research for synthetic natural gas from coal in fluidized bed were discussed from catalyst composition and preparation methods. Compared with methanation catalyst in fixed bed,in addition to highly active,high stability,sintering resistance and carbon deposition resistance,methanation catalyst used in fluidized bed must have good mechanical strength and abrasion resistance.Therefore methanation technology research in fluidized bed is focused on developing wear-resistant methanation catalyst.Improving the mechanical strength and wear-resistance of fluidized-bed catalyst by some methods such as choosing high strength load carrier,appropriate roasting temperature,spray granulation molding method,adding the appropriate dosage of binder are reommended.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 117K]

  • Characteristics and cleanliness class of coal seam in Shulan Street mining area

    HE Bao;LI Zhennan;LI Maofeng;JIANG Zaifu;College of Mining Engineering,Liaoning Technical University;No.102 Exploration Company,Jilin Bureau of Coal Geological Exploration;

    In order to efficiently and cleanly use the coal in Shulan Street mining area,the coal quality was analyzed based on the general geology,characteristics of coal-bearing strata and physico-chemical property.The type,industrial properties and usage of coal were determined according to the proximate analysis.The rank of coal cleanliness in this mining area was drew primarily from the aspects of ash and sulfur content on the basis of 6 grades of coal cleanliness class proposed for new coal resource potential evaluation. The results show that durain is the main lithotypes in as-mined coal,and huminite is the main maceral. The coal in this mining area is mainly long flame coal with medium-high ash,extremely low sulfur,extremely high volatile and low calorific value. The cleanliness rank of raw coal is Ⅵ,which belongs to low clean coal.The cleanliness rank of clean coal is Ⅲ which belongs to higher clean coal. After washing,coal possessed lower calorific value,higher tar yield,higher ST and FT,and its cleanliness are increased significantly.It thus can be used as steam coal,gasification coal and even coking coal with greater economic value.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 121K]

  • Characteristics of coal quality in Xinzhen exploration area of Xunxian

    WU Shuanghong;ZHANG Lin;ZHANG Huili;JING Xilin;DU Wanyi;Geophysical Survey & Remote Sensing Center in Henan Province;

    In order to understand the coal quality characteristics and process performance of II1 coal,and evaluate its industrial use,17 coal-core samples were taken and the physical properties,coal-rock characteristics,chemical properties and technological properties of type II1 coal were analyzed.The results show that,the Ⅱ1 coal seam is mostly powdery,also includes minor bulks and grains. The coal appears glassy and greasy lustre,partially,it appears to be metallic lustre,and the coal shows step-like fracture. The coal types consist of anthracite,meagre coal,meagre-lean coal,and coking coal,distributed by southwest to northeast in research area.The quality of Ⅱ1 coal seam is mid-low ash,high calorific value,especially low to low in sulphur and especially low to middle in phosphorous,and the fusibility of coal ash is high softening temperature ash and high flow temperature ash.Anthracite and meagre coal ars under the category of non-caking coal,meagre-lean coal belongs to slight caking coal,and coking coal is mid-strong caking coal.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 116K]

  • Factors affecting flotation process of coal slime

    ZHAO Bingbing;Beijing Huayu Engineering Limited Co.,Ltd.,China Coal Technology & Engineering Group;

    In order to research the factors affecting flotation process of coal slime,the flotation process of coal slime were studied by flotation experiments in Wangfenggang,Xinzhuangzi and Qidong coal preparation plants.The influence of coal slime property,collector dosage,ratio of fusel and alkyl glycoside and pulp density on the flotation efficiency were specifically studied. The experimental results show that flotation efficiency of coal slime in Wangfenggang coal preparation plant is the best with dosage of collector 600 g/t,ratio of fusel and alkyl glycoside is 2 ∶ 1,and the pulp density 100 g/L.Additionally,the clean coal yield is 76%,clean coal ash is 13 and floatation perfection is 53.1% in this case.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 193K]

  • Research on aggregation settlement of fine quartz by quaternary ammonium salt

    ZHAO Jianfeng;LIU Lingyun;CHEN Jun;LIU Chunfu;College of Material Science and Engineering,Anhui University of Science and Technology;

    In order to investigate the mechanism on aggregation settlement of fine quartz by quaternary ammonium salt,the aggregation settlement of fine quartz was carried out using different concentration of quaternary ammonium salt,i.e.,1231,1431,1631 and 1831.The effect concentration of quaternary ammonium salt on agglomeration settlement behavior of fine quartz particles was investigated by determining the light transmittance of supernatant fluid,sedimentation rate,Zeta potential and FTIR spectra.The results prove that within the concentration range of this study,high concentration of 1231( ≥0.8 mmol/L) can improve hydrophobic aggregation of quartz.The concentration of 1431 is very effective on hydrophobic aggregation of quartz under the concentration between 0.1 mmol/L and 1.6 mmol/L.As well,the concentration of 1631 and 1831 are very effective on hydrophobic aggregation of quartz under low concentration( ≤0.2 mmol/L). In addition,high concentration of 1631 and 1831( ≥0.4 mmol/L) may weak the aggregation settlement of fine quartz.Quaternary ammonium salt physically is found be adsorbed on the surface of quartz.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 220K]

  • Thermal behavior and kinetics of the pyrolysis of hyper coal

    GUO Longfei;ZUO Haibin;ZHAO Jun;WANG Yajie;WANG Jingsong;State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing;

    For the effective and clean use of low rank coal,hyper coal was obtained by organic thermal dissolved process. The pyrolysis process of raw coal and hyper coal was studied by thermogravimetric analysis methods.The characteristic parameters were used to characterize the process of pyrolysis of coal samples.The kinetics of different stages was determined by piecewise model fitting method and its corresponding pyrolysis kinetic parameters.The results show that there is a thermal hysteresis in the process of pyrolysis of raw coal and hyper coal with the increasing of heating rate,which has great influence on the medium temperature stages of raw coal and low temperature stage of hyper coal pyrolysis,respectively.By subsection analysis,the one-way transport diffusion model is adapt to lower and medium temperature range,and second order chemical reaction is adapt to higher temperature range of raw coal. The three stages of hyper coal pyrolysis process can be well described by one-way transport diffusion model,three-way transport diffusion model and second order chemical reaction,respectively.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 278K]

  • Cold model of gas-solid two-phase flow characteristics in fixed bed slagging gasifier

    DU Shi;FAN Junjie;ZHANG Zhongxiao;ZHANG Leyu;School of Environment and Architecture,University of Shanghai for Science and Technology;

    In order to study the effect of gasifier nozzle jet speed and installation angle of fixed bed slagging gasifier on the flow field in furnace,a cold model experimental platform of the fixed bed slagging gasifier was set up,and Fluent software was combined to simulate the process of gasifier.The results show that with the increase of gas injecting velocity,the penetration distance of the gas inside the material increases.The depth of jet,the radial depth of recirculation zone and the height of recirculation zone decrease continuously with the increase of dipping angle.The optimized dipping angle of the nozzle is 5°-10°achieving the suitable depth of penetration of the jet in horizontal direction inside the material layer and best furnace flow field distribution.With the continuous increase of nozzle tangent angle,the impact of the nozzle hedge collision becomes smaller,and the air flow gradually shifts from the radial region,as well the gas distribution of nozzle axis cross section gradually decreases; while the penetration depth of material jet fluctuates. Comprehensive consideration of various factors,the largest horizontal jet penetration depth inside the material layer and best furnace flow field distribution are obtained with 5° dipping and then 10° rotation of the nozzle.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 346K]

  • Pilot test study on new moving bed equipment for low rank coal pyrolysis

    ZHANG Yang;Coal Chemistry Branch of China Coal Research Institute;State Key Laboratory of Coal Mining and Clean Utilization;National Energy Technology and Equipment Laboratory of Coal Utilization and Emission Control;

    In order to explore the suitable process conditions for new moving bed equipment of low rank coal pyrolysis,analysis of temperature-control characteristics of the pyrolysis equipment using the non-stick coal in Northern Shaanxi was carried out.The pyrolysis pressure was higher than atmospheric pressure 3-5 mm water column,and the reaction time was 2 h.The temperature was set to be 550、600、650、700 and 750 ℃.The results show that temperature-control system of the pyrolysis device performes smoothly,and material temperatures are always lower 50-80 ℃ than that of the furnace wall.Semi-coke can be completely pyrolyszd in different temperatures,and the volatiles of semi-coke is reduced from 14. 74%( at 550 ℃) to 6. 34%( 750 ℃).The pulverization is found during the pyrolysis,and the degree of the pulverization increases with the increase of the final pyrolysis temperature,as well the content of light component in pyrolysis tar can reach 66%-73%.In addition,the multi-section dust reduction process works with good performance,and the dust content in the pyrolysis tar is less than 1%.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 282K]

  • Theoretical calculation of heat and mass balance during retorting process of semi-coke production

    HOU Jili;MA Yue;LI Shuyuan;LIU Junli;State Key Laboratory of Heavy Oil Processing,China University of Petroleum-Beijing;Shenmu Sanjiang Coal Chemical Industry Co.,Ltd.;

    In order to verify the feasibility of retorting process of Shenmu Sanjiang type rectangular gas combustion retort( SJ-retort) for semi-coke producing,Shenmu bituminous coal( SM coal) was taken to study the heat and mass balance during retorting process of SJ-retort combined with the basic properties analysis of SM coal,pyrolsis product,structure and process of SJ-retort.Results show that the heat requirement of 1 t SM coal retorting( 1 299. 08 MJ) can be satisfied by its heat transfer of retorting products( 634. 83 MJ) and retorting gas( 23. 37 m~3) combustion( 664.25 MJ),and 1/2 surplus retorting gas is obtained.In steady state of retorting system,total feed and totl output are 1 406 and 1 390 kg,which loss is 16 kg.Calculated results also reveal that the total input gases,output gases,recycle gases,new input air and release gases at steady state of retorting system are 238,276,94,144 and 182 m~3,respectively indicating a dynamic equilibrium of various types gases.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 170K]

  • Influence of magnesium compounds on gasification reaction of petroleum coke and its kinetic model

    TIAN Wei;YAN Fusheng;HUANG Yonghong;School of Metallurgy,Northeastern University;Foshan Juchao Energy Co.,Ltd.;

    The magnesium compounds were used as catalysts for petroleum coke-CO_2 gasification.The effects of catalyst type,catalyst addition amount and gasification temperature on petroleum coke-CO_2 gasification were studied by using thermogravimetric analyzer.It is shown that the catalytic activity of MgCl_2 is higher than other magnesium catalysts.The catalytic activity increases with the rising of reaction temperature.Under higher gasification temperature,the reaction time is shortened with more additive amount of MgCl_2. The kinetics model of petroleum coke catalytic gasification is described by using the homogeneous model,the shrinkage model and the Gaussian model respectively.Compared with the gasification reaction activation energy calculated by the conversion method,the homogeneous model is better to describe the dynamic characteristics of catalytic gasification of petroleum coke.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 1230K]

  • Prediction of coal ash melting behavior using FactSage

    SONG Mingguang;WANG Qunying;YUE Yifeng;CHEN Shiguo;Huandian Electric Power Research Institute;

    The melting behavior of coal ash is an important characteristic in pulverized coal combustion and coal gasification. In order to predict coal ash melting behavior quickly and accurately,the application and characteristics of FactSage software in predicting coal ash melting behavior was introduced. Results show that that FactSage software can be used to guide resource utilization of coal ash through drawing multi-component phase and generalized phase diagram and preparation of glass ceramics and glass fiber. In addition,it is found that FactSage software can be widely used in predicting the fusion temperature,drawing simplified phase diagrams,forecasting viscosity-temperature characteristics and studying the regularities of coal ash melting characteristics through adjusting the composition of coal ash.Briefly,the FactSage software is an efficient tool for predicting coal ash melting behavior because of its high efficiency and accuracy.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 175K]

  • Correlative analysis of coal ash composition and ash fusion

    LU Cai;ZHAO Junmei;RONG Lingkun;JIA Fengjun;WANG Xiong;School of Mining and Coal Industry,Inner Mongolia University of Science & Technology;

    In order to study the influence of coal ash composition on ash fusion in Ordos,the effect of total acid,total alkalinity,acid-base ratio,melt index FI and coal ash content on ash fusion were analyzed.The regression equation of coal ash melting temperature was obtained by combining the MATLAB simulation.The results show that with the increase of acid-base ratio,the melting temperature of coal ash gradually increases,likewise,the melting temperature of coal ash increases significantly with the acid-base ratio over 3. 65. According to the gray melting temperature regression formula,the minimum FI value of the melt index is 35. 67%,and the prediction formula of the melt index could not reflect the trend of the FT.In gasification coal,the ash melting temperature is determined by many kinds of minerals. When the Si/Al ratio is less than 3 and the CaO content is less than 30%,the coal ash has a lower melting temperature.When the content of CaO exceeds 30% and the content of Fe_2O_3 exceeds 20%,monomeric CaO and FeO are usually produced,while the monomer CaO and FeO have higher melting temperature,so that the melting temperature of coal ash also increases accordingly.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 150K]

  • Effect of iron powder by cold rolled friction as flux on the melting characteristics of coal ash from Jiulishan Coal Mine in Henan province

    WANG Hang;YUAN Chunwei;ZHAO Jigang;KONG Lingtao;China Kunlun Contracting & Engineering Corporation;Petroleum Processing Research Center,East China University of Science and Technology;Key Laboratory of Coal Clean Conversion & Chemical Engineering Process,Xinjiang University;

    In order to utilize the wastes of magnetic filtration products in cold rolling by combining with the requirements of liquid slagging in large scale coal gasification furnace,the properties of iron powder from the magnetic filtration products in cold rolling emulsion were characterized.The effect of iron powder as flux on coal ash melting characteristics from Jiulishan coal mine in Henan province( RC) was investigated.Results show that the particles size distribution of iron powder is between 0. 6 μm and 16 μm,and the iron content is more than 98%( metal content based on metals oxide).Mullite formed under high temperature leads to a high coal ash melting temperature with 1 510 ℃,and the coal ash melting temperature will be decreased to 1 340 ℃ with addition of 2% flux of iron powder.The low temperature eutectic mixtures,such as fayalite and hercynite,are easily generated from ferrum compounds under high temperature,which will remarkably decrease coal ash melting temperature.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 197K]

  • Numerical analysis of coal water mixture combustion in double cone reversed injection burner

    MO Rigen;WANG Naiji;CHENG Xiaolei;China Coal Research Institute;State Key Laboratory of High Efficient Mining and Clean Utilization of Coal Resources;National Energy Technology and Equipment Laboratory of Coal Utilization and Emission Control;

    In order to study the differences between the combustion processes in double cone reversed injection burner of coal particle and coal water mixture,numerical simulation model of 14 MW reversed injection burner was built based on CFD software Fluent. The results show that the velocity fields of coal particle and coal water mixture are basically similar.The vaporization of water in the coal water mixture increases the resistance of the burner and the residence time of the discrete phase particles in the combustor.Due to the high moisture content,the ignition position of coal water mixture is lagged by 110 mm,compared with coal particle.The average temperature and outlet temperature in the burner with coal slurry are reduced by 162 K and 199 K,respectively,compared with that of coal particle.The core temperature zone of the coal water mixture torch is 438 mm ahead of the coal particle.And the rigidity of the coal water mixture troch is stronger than that of the coal particle.But the decay rare of the coal water mixture torch is faster than the coal particle's.The combustion characteristics of coal water mixture are in the effective range of the combustion control of reversed injection burner.It is proved that the optimization of combustion principle is one of the effective methods to solve the contradiction between the combustion temperature and efficiency of coal water mixture.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 493K]

  • Oxygen-enriched combustion characteristics of typical coals in China

    ZHANG Daxing;Guohua Huizhou Thermal Power Branch Company,China Shenhua Energy Co.,Ltd.;

    In order to completely elucidate the different coal's combustion performances under oxygen enriching condition-and provide reference for oxygen concentration selection,boiler and burner design,as well as the heating surface arrangement,the ignition temperature,burn-out rate,slagging characteristic of typical bituminous coal and lean coal were tested on a one-dimensional flame fire furnace and a modified pulverized coal-air flow test furnace under different oxygen concentrations.The results show that the ignition temperature decreases and the burnout rate raises with the increasing of oxygen concentration.The enriched-oxygen combustion can improve combustion stability and combustion economy of coal.Likewise,the combustion peak temperature increases and slagging aggravates.It should be noted that the effects of oxygen concentration on the combustion performance for different type coal are varied.The coal sample needs to be tested with specific oxygen-enriched combustion to determine its combustion performance.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 373K]

  • Experimental study on the hydrogenation of coal tar light oil to clean fuel

    HU Fating;Coal Chemistry Branch of China Coal Research Institute;State Key Laboratory of Coal Mining and Clean Utilization;

    Because of the shortage of petroleum in China,it has great significance to produce fuel oil and fine chemicals from the hydrogenation of considerable amount of coal tar.Three kinds of mixed oil from light distillated oil were used as raw feedstocks to carry out the hydro-refining experiment in a fixed bed hydro-refining unit.The influence of reaction pressure and temperature,liquid volume space velocity,hydrogen/oil ratio on the produced oil properties were investigated.The results indicate that the nitrogen content,sulfur content and aromatic content of products decrease with the increase of reaction temperature,pressure and hydrogen/oil ratio,but increase significantly with the rising of liquid volume space velocity.Under the optimum condition of the reaction temperature at 360 ℃,reaction pressure at 16 MPa,liquid volume space velocity at 0.25 h~(-1) and the ratio of hydrogen/oil at 1 800,the yield of the produced oil is up to 98. 03%.The produced oil is distilled to obtain naphtha <170 ℃ and diesel oil >170 ℃.The naphtha fraction has a density of 776.9 kg/m~3 at 20 ℃,no sulfur and nitrogen are detected,and the latent content of aromatics is 67.6%.It can be used as a high quality catalytic reforming raw materials.Diesel fuel has low aromatics content,without sulfur nitrogen,high flash point,low condensation point and is suitable for distillation,thus it can be used as a blend of diesel oil.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 191K]

  • Low temperature flue gas denitrification performance of carbon materials prepared by blending coal method

    XIE Wei;QU Sijian;WANG Peng;LIANG Daming;LI Xiaoliang;WU Qian;School of Chemistry and Environment Engineering,China University of Mining and Technology ( Beijing);Coal Chemistry Branch of China Coal Research Institute;Beijing Key Laboratory of Coal Based Carbon Materials;

    In order to study the coal blending affected to the pore structure and surface chemistry properties of carbon material for denitrification from flue gas,carbon material samples were prepared by blending coal from bituminous and anthracite. Pore structures of samples were calculated N_2 adsorption/desorption at 77 K by density functional theory.Surface chemistry of theses carbons had been characterized by X-ray photoelectron spectroscopy( XPS) and acid-base titration.Denitrification experiments from simulated flue gas of 1 000×10~(-6) NO concentration by carbon material samples were conducted on a fixed bed reactor at temperature 150 ℃.The results show that pore structure development of carbon material prepared by blending bituminous and anthracite both have two raw material coal feature,whereas its surface chemical more rich than carbon material prepared from single coal.An ideal correlation between SCR catalytic activity and acidic sites content is observed and correlation coefficient R~2 reaches 0. 969.The NO conversion seems to be promoted by presence of oxygen in flue gas.Increasing the gas-phase H_2 O concentration decreases catalytic activity of carbon material. It can be concluded that the H_2 O molecules compete with NH_3 for the same hydrophilic acid oxygen containing functional groups because molecular of H_2 O has more polarity than NH_3.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 243K]

  • Influencing factors and mechanism of catalytic oxidation at low temperature for NO removal by activated coke

    ZHANG Yuan;WANG Naiji;XIAO Cuiwei;LIANG Xing;ZHANG Xin;Energy Conservation and Engineering Technology Research Institute,China Coal Research Institute;State Key Laboratory of Coal Mining and Clean Utilization;National Energy Technology and Equipment Laboratory of Coal Utilization and Emission Control;

    In order to study the catalytic oxidation characteristic of activated coke at low temperature,long period bench test was adopted in this study.The proportion of compounded modeled flue gases components came from operational pulverized coal industry boiler. Emphasis was placed on reaction temperature,oxygen concentration,air-speed and SO_2 concentration which had a great importance in denitration efficiency.Meanwhile,the infrared spectroscopic analysis and thermogravimetric analysis had been carried out on the fresh activated coke and deactivation coke.The results show that when the temperature increases from 50 ℃ to 90 ℃,the denitration efficiency will obviously decline and the valid time for denitration will decline to 2.3 hours from 81 hours.When the oxygen concentration goes up to 10% from 0,the valid time will rise to 35 hours from 0.6 hours.And the valid time will decrease to 0.26 hours from 15 hours,after the airspeed increasing to 2 500 h~(-1) from 500 h~(-1).In addition,the valid time will decline to 1.6 hours from 15 hours with the SO_2 concentration up to 200× 10~(-6) from 0.The infrared spectroscopic and thermogravimetric analysis also indicate that NO could be catalytically oxidized to NO_2,which is significantly adsorbed by activated coke at low temperature.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 263K]

  • Removal properties and migration patterns of mercury in coal-fired power plant

    CHE Kai;LI Zhenhai;HAN Zhongge;YU Jinxing;CHEN Chongming;State Grid Hebei Electric Power Research Institute;

    In order to study the characteristics of mercury distribution and migration,EPA OHM method was used to determine the Hg concentrations in flue gases emitted from two typical pulverized coal-fired boilers.Then the effect of major flue gas purification systems on Hg emission was clarified.Experimental results indicate that Hg~0 will be catalytic oxidation into Hg~(2+)in SCR system that promotes the mercury be absorbed by fly ash and desulfurization slurry in WFGD system.ESP system and WFGD system plays the leading role foe mercury removal which the total removal efficiency reach more than 60% and WESP system has only limited removal effect.Ash content of coal particles can affect the ratio of granular mercury between the gaseous mercury. The absorption of Hg~(2+)will be inhibition by SO_2,caused Hg~0 emissions again,which affects mercury removal efficiency of WFGD system. In addition,most of the Hg is transferred into desulfurization gypsum and fly ash,and smaller particle size of fly ash has the stronger adsorption ability to mercury,while the enrichment ability of bottom slag is limited.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 187K]

  • Analysis on production process of coal to oil with life cycle assessment

    ZHU Ling;FENG Xiangzhao;KONG Jiawen;Department of Environmental Engineering,Beijing Institute of Petrochemical Technology;Division of Climate Change Policy Research,Policy Research Centre for Environment and Economy,MEP;

    Based on the spot investigations and annual report statistics of a coal chemical factory,the total energy consumption and pollutants discharge of the entire process were calculated and analyzed by LCA methods,including the coal mining process,transportation process and coal to oil process.In order to promote the low carbon and green development of coal chemical industry on the assumption of ensuring energy security and clean using of energy,the environmental impacts were also identified,and the major pollution processes and pollutants were determined.The results show that production of 1 ton coal-based oil,the total discharge of gaseous pollutants is 16. 56 t,among which CO_2 is about 98.03% of the total emissions.It is mainly from the adjustment of C/H atomic ratio in the processing step and combustion discharge in the energy power generation step,being 53.9% and 25.87% respectively.The total amount of greenhouse gas emissions calculated by CO_2 is about 16.23 t,acidification gas is 33.847 kg SO_2,eutrophic composition is 30.483 kg PO_4,and photochemical smog generated is 2.651 3 kg C_2H_4,as well as dust is 0.834 kg.The total discharged wastewater is 8.204 4 t/t oil,and 68.74% of which is from the production process.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 198K]

  • Technical and economic analysis of compressed natural gas production with coal-bed methane

    LI Xuefei;Coal Chemistry Branch of China Coal Research Institute;State Key Laboratory of Coal Mining and Clean Utilization;National Energy Technology & Equipment Laboratory of Coal Utilization and Emission Control;

    In order to increase the utilization rate and extend the utilization routes of low concentrated coal-bed methane,the equipments selection,utility consumption and project investment as well as economy and cost were calculated on the basis of as-developed low concentrated coal bed methane( CBM) upgrade to compressed natural gas( CNG) technology,with an annual output of 20 million standard cubic meters natural gas project as example.The results shows that the electricity consumption is 15.625 6 million kWh; the water consumption is 26.72 thousand tons; the gas consumption is 0.96 million Nm~3; the floor area is 18 thousand m~2.The total investment of this project is $ 78.46 million; while the construction investment is $ 69.9 million. The construction cost is $ 56. 21 million and the other costs are $ 22. 25 million.Accordingly,when the selling price of CNG is $ 2.6 per Nm~3,financial internal rate of return of the project is 31.87%( after tax);while the investment recovery period is 4.44 years( including 1.5 years construction period).And the unit product cost is $ 1.3 per Nm~3.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 138K]

  • Optimization on key technologies of GSP dry pulverized coal gasification

    MA Yinjian;JING Yunhuan;Shenghua Ningxia Coal Industry Group Co.,Ltd.;

    In order to solve the problems in GSP dry pulverized coal gasification technology,such as ignition,water wall burner face burning,burn-through of water wall,crude gas with serious ash,and high solid content in washing water,the combination of gasifier burner and crude gas washing system were optimized and the performance was analyzed.Through the methods of high energy ignition improving hightemperature-resistance of oxygen nozzle,accessing high pressure steam,changing cooling system of cooling water in ignition burner,increasing gas liquid separation tank,bubbling tower and tray,redesign of washing water process,optimization of bypass flash system,setting the static mixer,the burner ignition success rate is increased up to more than 98% from 40%,and synthetic gas dust content is reduced to below 0.5 mg/m~3 from 20.5 mg/m~3.Effective gas production reaches up to 143 856 m~3/h,and heat loss of water cooled wall is reduced.Operating time of the gasifier in 2012 is extended 2-3 times higher than that of 2011.It solves the technical bottleneck of long-term operation of the device,and gradually makes the gasification device to achieve a full load,long period and stable operation.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 127K]

  • Experimental research on blunt body reforming of 20 t/h pulverized coal industrial boiler

    GUO Mengmeng;LIANG Xing;ZHOU Jianming;WANG Yongying;China Coal Research Institute;China Coal Research Institute Company of Energy Conservation;State Key Laboratory of Efficient Mining and Clean Utilization of Coal Resources;National Energy Technology and Equipment Lab of Coal Utilization and Emission Control;

    In order to improve the combustion efficiency of 20 t/h coal-fired industrial boilers in Shendong mine,combined with the structural characteristics of the double-cone center reverse-blown burner developed by China Coal Research Institute,the conical blunt body was designed in the burner.After the hot body bench test,it is found that the combustion efficiency of pulverized coal is improved and the flame rigidity is enhanced.During the field modification test,the steam output is stable and the negative pressure fluctuation of the furnace is reduced when the blunt body is installed,as well the temperatures of the burner and the coking furnace are reduced.The comparison of the four-blunt bodies with the width aspect ratio of 0.60,0.65,0.70 and 0.75 are carried out. The results show that the optimum ratio of blunt body with a width aspect of 0.65 in the 14 MW burner with 20 t/h boiler in Shendong mine achieves the highest efficiency of boiler combustion and less ash-like residual carbon rate.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 584K]

  • Low NOx combustion retrofit on a low volatile coal tangentially fired boiler

    LI Jieyi;LIU Xing;LI Bing;LIU Yingjin;MO Qingfeng;ZHEN Zhiguang;TAN Houzhang;Shijiazhuang Liangcun Thermal Power Co.,Ltd.;Schol of Energy and Power Engineering,Xi'an Jiaotong University;

    In order to solve the problems of low volatile coal that usually shows poor ignition performance and higher NO_x emission,traditional low NO_x combustion technology may lead to worse ignition condition for the pulverized coal.A low volatile coal tangentially fired 330 MW utility boiler was retrofitted by adopting ignition enhancement and low NO_x burner technology.Compared with the results before the retrofit,the NO_x emission is decreased from 550-600 mg/Nm~3( 6% O_2) to 350-400 mg/Nm~3.The consumption of liquid ammonia is reduced from 150-200 kg/h to 100-150 kg/h.And the NO_x emission at the stack is decreased from 70 to 35 mg/Nm~3 after modification.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 239K]

  • Research and application of hydrogen sulphide prevention and cure technology with stent coal

    CHENG Li;China Coal Technology and Engineering Group Chongqing Research Institute;

    In order to solve the problem of over-limit of local concentration of hydrogen sulfide gas during the operation of Wudong Coal mining,the measuring points were set up to monitor the diffusion and distribution of disturbance and emission of hydrogen sulfide from support caving.The key influencing factors of hydrogen sulfide treatment was studied by spraying absorption liquid.Accordingly the the processing technology for discharging hydrogen sulfide from the scaffolding by spraying the absorption liquid was carried out.The design and layout of the spray absorption liquid device were also investigated.The process parameters for controlling the hazard of hydrogen sulfide emission from the coal support during coal caving were optimized through the experimental study on the spray absorption liquid.The practical results show that the hydrogen sulfide in the chute and the side-walk drop to 186×10~(-6) and 32.6×10~(-6) respectively after 6 m of downwind flow,and the reduction efficiency of hydrogen sulfide are 86.1% and 84.6% respectively after placing the coal on the support. Eventually,good control effects are achieved.

    2018 02 v.24;No.114 [Abstract][OnlineView][HTML全文][Download 310K]
    • 下载本期数据


Clean Coal Technology            京ICP备05086979号-19

Website  Copyright © 2019 Clean Coal Technology 
Coal Tower, Hepingli, Chaoyang District, Beijing, China. 100013
Tel:  86-10-87986452 / 010-87986451           E-mail:  jjmjs@263.net