• Influence of grading size on slurryability of Shenfu coal

    ZHU Xuedan;College of Chemistry and Chemical Engineering,Xi'an University of Science and Technology;

    In order to enable Shenfu coal to have a better slurryability,analyze its raw coal characteristics. Its slurrying index is 11. 55 which indicates that the coal is difficult to form coal water mixture( CWM). Conduct the screen analysis of different dry coal samples. Taking coarse powder,fine powder and different grading size coal respectively as research object,investigate their slurryability. The results show that,after particle size gradation,the coal samples have double-peak particle size distribution which is benefical to the formation of CWM. The coarse powder can't form CWM alone,the maximum CWM concentration is 61% when using fine powder. When the ratio of coarse and fine coal powder is 1∶ 2,the CWM has good liquidity and stability. The highest CWM concentration can reach 63. 8%,the viscosity is 1000mPa·s. Each indicator meets the standard of industrial CWM preparation. So appropriate grading size helps to form high quality CWM.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 290K]

  • Low separation limit of three-product dense medium cyclone

    HAO Kai;ZHAO Shukai;HU Ting;School of Chemical and Environmental Engineering,China University of Mining and Technology( Beijing);

    In order to determine the low separation limit of non-pressure three-product dense medium cyclone,test the low separation limit of three-product dense medium cyclone of a coking coal preparation plant by the way of clean coal sieve analysis and accumulated ash,clean coal sieve analysis and distribution curve determination. Compare the advantages and disadvantages,application scope of the three ways. The results show that the low separation limit determined by the three ways all are equal or greater than 0. 5 mm. The way of clean coal sieve analysis needs small workload,a short period of time,but it has poor objectivity. The way of clean coal sieve analysis and accumulated ash is greatly influenced by coal slime size composition. The way of the distribution curve determination can determine the low separation limit objectively,which is less influenced by some facts while it needs heavy workload. So the way of clean coal sieve analysis and clean coal sieve analysis and accumulated ash apply to evaluation of equipment performance monthly or quarterly in coal preparation plant,while the way of the distribution curve applies to study of gravity concentration equipment performance and determination of process before new equipment investment in research design department.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 129K]

  • Experimental study on re-preparation technology of tailings of TBS

    FAN Haiwei;YUE Zengchuan;DU Wanlei;WANG Jian;XIAO Xingwang;XU Lei;School of Chemical and Environmental Engineering,China University of Mining and Technology( Beijing);

    In order to improve the utilization of coking coal,taking the tailings of TBS from one coking coal preparation plant as study object,and rod mill trials of different time are experimented. In the end,particle size analysis,density analysis and float experiments are done to the grinding products. The results show that the product grinded for 12 minutes has more appropriate size composition and better dissociation under the condition of the pulp density is 30%,mill speed is 50 r /min,medium filling rate is 40%,the grain of 0. 075 to 0. 250 mm content is as high as 64. 39% while + 0. 250 mm and-0. 045 mm size fraction are little. The dissociation effect is good,intermediate density level of 1. 40 ~ 1. 60 g /cm3 content is 28. 25%,-1. 40 g /cm3 content is 40. 32%. With the help of rougher-cleaner system,the clean coal yield and flotation perfect index is 33. 89% and 24. 30%,clean coal ash is 12. 93%. The best grinding time is 12 minutes.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 264K]

  • Design and application of 45m~3 mechanical flotation machine

    ZHANG Peng;Tangshan Research Institute Co. ,Ltd. ,China Coal Technology and Engineering Group;Coal Separation Engineering and Technology Research Center of Hebei Province;

    Research and design a 45 m3 mechanical flotation machine in order to achieve a large-scale,high efficiency,energy conservation flotation machine. Describe the structure and operating principle of the flotation machine,focus on the structural design of the tank impeller,stator,scraping bubble agencies,steady flow plates in the flotation machine. The performance test by water flotation machine show that,when the impeller speed is 137. 58 m /s,immersion depth is 895 mm,the flotation machine has a optimal process indicators. The application of 45 m3 mechanical flotation machine in Dayangquan coal preparation plant shows that,the ash of clean coal is 10. 69%,the ash of tailings is 55. 35%,the yield of clean coal is 68. 03%. The flotation machine has good recovery effects on different size fractions slime.Compared with FCMC3000 flotation column,in the case of the feed ash has a little difference,the tailings ash,coal yield,combustible body recovery,improve index of the XJM-S45 flotation machine flotation increased by 18. 61%,18. 84%,23. 90%,18. 30%.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 219K]

  • Select on anthracite washing and processing technology in Nuodong mine

    JI Yinghua;ZHANG Zhenhong;Yongcheng Coal Company,Henan Energy and Chemical Industry Group;

    To improve the separation effects of anthracite,taking Nuodong mine as research object,analyze the coal quality characteristics,size composition,washability and floatability. The results show that the raw coal is low and low-medium ash,high-medium and high sulfur,low phosphorus,extra-low anti-breaking strength anthracite,the sulfur in coal is in the form of inorganic iron sulfide. Higher fine coal determines that its separation needs to be strengthened,the coarse slime can be individually sorted,the products are easy to dehydrate,the coal washability is medium optional. Combined with the properties of raw coal,determine the product positioning of Nuodong coal preparation plant is that,the seventeenth coal separation lump coal is used in coal chemical industry,clean coal is used in blast furnace blowing. The twentieth coal separation lump coal is used in coal chemical industry,clean coal is used in pulverized coal injection into blast furnace. Through analyzing the features of the common preparation methods and process,determine the anthracite sorting scheme in Nuodong coal preparation plant. Before separation,treat the + 100( 80) mm size with hand picking method,separate the-100( 80) mm size with jigging,coarse slime with teetered bed separator,select the fine slime with flotation,concentrate the tailings by filter pressing.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 122K]

  • Measures of reducing moisture of fine clean coal in Sitai coal preparation plant

    AN Yao;Sitai Coal Preparation Plant,Clean Coal Branch of Datong Coal Mine Group Co. ,Ltd.;

    To reduce the moisture of fine clean coal of Sitai coal preparation plant,analyse the product composition and moisture,find that high moisture of coarse slime and filter cake are the main reasons. To resolve this problem,take the following measures. First,replace the traditional sieve bend with the intelligent vibratory one,flip the screen surface regularly,add belt to screen surface in order to slow the speed of slurry. Second,increase the sieve seam of FC1200 centrifuge from 0. 375 mm to 0. 500 mm and adjust the operation parameters of hydrocyclone group. Third,improve maintenance of filter and adjust process parameters promptly according to the feed concentration.Fourth,introduce a vertical filter HVPF-120 m2,and increase ash to lower moisture by adding coal screening system. By these measures,the moisture of fine clean coal decrease from 15. 72% to under 14. 00%,which reduce the belt slipping in product transportation system and decrease the labor intensity. Beyond that,the clean coal no longer freeze the railway cars. The measures ensure the normal outward transport of Sitai coal preparation plant and saves transport costs 5. 4 × 106 yuan.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 102K]

  • Present situation and prospect of steam coal separation in China

    QIAN Aijun;Tangshan Research Institute Co. ,Ltd. ,China Coal Technology and Engineering Group;Coal Washing and Engineering Technology Research Center of Hebei Province;

    In order to improve the separation proportion of steam coal,introduce the separation features. Optimize process of separating steam coal by the contrasting dry coal preparation,discharge of refuse by jigging,discharge of refuse from lump coal by dense medium separation without small coal feed,three products H. M. cyclone separation of all raw coal and discharge of refuse by H. M. vessels and cyclone.It is necessary to select energy-efficient and water saving equipment with large capacity of unit to reduce cost of production and capital investment. Provide that large-scale,efficiency,generalized and modularization is the development tendency. Introduce large-scale efficient packaged technologies and key equipments used for the separation of lump coal,slack coal and fine coal in ten-million-ton steam coal separation. Meanwhile,develop matching large-capacity sizing crusher and medium drainage or dehydration equipments.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 104K]

  • Improvement of products calorific value in Lijiahao coal preparation plant

    SUN Jingyang;Beijing Huayu Engineering Co. ,Ltd. ,China Coal Technology and Engineering Group;

    The analysis of raw coal supplied to Lijiahao coal preparation plant show that,it's low-medium ash and sulfur,extra low phosphorus,high calorific value non-caking coal and long flame coal. There are lots of gangue in raw slime and the gangue is easy to degrade,so it needs to minimize the contact time between coal,gangue and water during separation. The ash of secondary slime is 74. 23%,the gangue degrade seriously and mainly exist in-0. 045 mm fine slime. Transform the coal preparation plant by improving management,reforming coal handing equipments,adding supplement coal system,fine slime and gangue discharging systems. After transformation,the raw coal moisture reduces by an average of 3%,the supplement of high-quality coal can improve the coal delivery situation in raw coal bunker,products bunker and coal handing equipments. The fine slime can be recycled rapidly,the calorific value of lump clean coal and mixed slack coal can be improved obviously,the coal preparation plant increases profits 3 × 107 yuan per year.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 110K]

  • Measures of reducing medium consumption of Kaida coal preparation plant

    ZHANG Gangjian;Beijing Huayu Zhongxuan Clean Coal Engineering Technology Co. ,Ltd.;

    Analyse the causes of high medium consumption of Kaida coal preparation plant from technology loss and management loss. The results show that,bad effects of raw coal desliming and dewatering,low efficiency of medium draining screen and magnetic separator,poor quality of magnetite powder,unreasonable medium adding way,unstable density of medium collection system,delayed screen surface clean,poor management of magnetic separator and so on are the main causes. Reform the coal preparation plant by optimizing performance of magnetic separator,increasing efficiency of desliming screen and medium draining screen,realizing the automation control of medium system and strengthening daily management. After transformation,the efficiency of magnetic separator reaches above 99%,the medium in products decrease. Medium system tends to more stable and products quality is ensured. The medium consumption decrease from 1. 99 kg /t to 1. 10 kg /t,and the plant saves about 4. 26 × 106 yuan per year.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 109K]

  • Improvement of lump coal yield in Longshan coal preparation plant

    SONG Jingling;Longshan Coal Preparation Plant,Anyang Xinlong Coal Mining Group Co. ,Ltd.;

    In order to increase the lump coal yield in Longshan coal preparation plant,analyze the raw coal properties. The results show that,the raw coal is medium and high ash,extra low sulfur No. 2 anthracite. There is less primary slime and the gangue is harder which is difficult to crush and grind. There is obvious degradation phenomenon. When lump coal ash is above 12%,the raw coal is easy to wash.The analysis of the process flow of coal preparation plant show that,low screening efficiency,frequent collision and high drop distance lead to low lump coal yield. To resolve these problems,replace the drum screen with linear vibrating screen,the raw coal bunker or lump coal point install spiral chute and take other measures to reduce coal breakage. After transformation,the lump coal yield increase by 1. 74%,the medium-sized lump coal increase by 0. 51%,the small lump coal increase by 1. 23%,the plant creates benefits 2. 3868 ×106yuan per year.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 289K]

  • Feasibility study on flotation in Huaheng coal preparation plant

    ZHAO Jianjun;ZHANG Zhongwei;REN Fuqian;Shandong Huaheng Mining Co. ,Ltd.;Shandong Mining Management Technology Services Group Co. ,Ltd.;

    To resolve the problems such as single coal separation method and low slime recovery in Huaheng coal preparation plant,test the flotability through screen analysis,standard substep release test and flotation test. The results indicate that the proportion of + 0. 5 mm particles in the slime is only 0. 18%,which is suitable for the flotation conditions,the content of-0. 25 mm particles is 99. 23%,which meets the requirement of particle size in the flotation. The optimized reagent schedule is that the ratio of light diesel and GF is 9∶ 1,the dosage of mixed reagents is 1000 g /t,while the productive rate of the clean coal is 46. 28%,the clean coal ash is 11. 76%,the recovery of combustible materials is 73. 99%. So the flotation is suitable for the separation of the slime. According to the practical situations of the coal preparation plant,the necessity of the slime flotation is analyzed,and the economic benefits has been estimated,the program of slime flotation system is feasible in the construction space and processing layout. The blend of clean coal of the slime flotation and the washing clean coal can hold the moisture of clean coal,decrease the overstock of coal slime,relieve the operating pressure and increase the sales revenue by 1. 5309 × 107 yuan per year.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 118K]

  • Optimizing research of different coal mix processing dynamic control model

    YANG Zhiwen;Technical Center,Datong Coal Mine Group;

    In order to improve products quality in preparation of unsized raw coal,based on lump coal production index and technical parameters of Yanzishan coal preparation plant as well as the mixing ratio of two kinds of raw coal,taking Jurassic and carboniferous raw coal in Datong coal mine as research object,establish and optimize dynamic control model between technical parameters and products quantity and quality. Forecast the dynamic change trend of product quantity and quality,lump coal separation density. The results show that the optimized production rate of lump coal,ash content,moisture content and calorific value optimization model of the correlation coefficient R increase by 0. 07245,0. 22410,0. 15157,0. 16059 respectively,lump coal production index dynamic control model is improved significantly.After regulation,the yield and calorific value of product increase by 1. 10% and 0. 45 MJ /kg,the ash decrease by 1. 28%. The regulation realizes the effective control of coal products quality.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 361K]

  • Application of low thermal stability and low-rank coal in crushed coal pressurized gasification process

    HAN Yufeng;DING Jianchu;Xinjiang Longyu Energy Zhundong Coal Chemical Co. ,Ltd.;

    In order to improve the effects of low thermal stability and low-rank coal in crushed coal pressurized gasification,adopt the crushed coal pressurized gasification processes in Henan and Xinjiang Province,investigate the influence of thermal stability of low-rank coal on crushed coal pressurized gasification. The results show that single gasifier oxygen load can only reach about 70% of design load when use low stability and low-rank coal,about 40% less than the high stability and low-rank coal. Thermal stability of coal is lower and the higher dust content in raw gas affects the gas-water separation,it also influents the transform and follow-up processes. The effects of low thermal stability and low-rank coal in crushed coal pressurized gasification can be improved through investigating the thermal stability of different particle size of coal,determining minimum grain size of pulverized coal into the gasifier and the particle size of pulverized coal in the crushed coal pressurized gasification process,improving the dust removal system,selecting the reasonable gasification pressure,combining gasification process.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 156K]

  • Medium consumption reduction methods in Tongyuan coal preparation plant

    WANG Dongxing;Engineering Design Center,Tangshan Branch of Tiandi Science and Technology Co. ,Ltd.;

    The medium consumption for per ton raw coal is up to 3 kg due to imperfect technique,equipments and operation in the early stage of debugging in Tongyuan coal preparation plant. The medium consumption is an important indicator to measure the technological and management level as well as the economic benefits of coal preparation plant. To reduce medium loss and improve the economic benefits of plant,change the equipments parameters,stabilize the raw coal quality,improve the operation level of workers by analyzing the raw coal properties,process and actual production. After transformation,the medium consumption reduce to less than 2 kg for per ton raw coal.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 106K]

  • Experiment and application of middle and high sulfur lean coal blending coking technology

    ZHANG Ligang;Shaanxi Shaanhua Coal Chemical Group Co. ,Ltd.;Shaanxi Coke Chemical Co. ,Ltd.;

    In order to expand the coking coal resources and reduce the cost of coal blending,taking the middle and high sulfur lean coal as the test sample,which is taken from No. 10 coal seam of western areas of Weibei coalfield in the southern of Erdos Basin. The middle and high sulfur lean coal contains low ash,its bond index and thickness of plastic layer is higher than that of generally lean coal,the inert and alive of petrography is close to 2,and the coking property is well. Through the coking test of middle and high sulfur lean coal,simulated coal blending of coal petrography,industrial coke oven coking test,verify the feasibility and determine the optimizations of middle and high sulfur lean coal blending coking. The results show that middle and high sulfur lean coal can be used in coal blending for coking,the blending content of middle and high sulfur lean coal should be controlled below 10%,and high content of strong caking index blending coal can enhance the thermal state index of coke. According to coal blending coking in industrial application of middle and high sulfur lean coal,show that using middle and high sulfur lean coal coking can produce quality qualified coke blending ratio of 3% ~ 7%,expand coking coal resources and reduce the cost of blending coal using middle and high sulfur lean coal coking.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 192K]

  • Influence of briquetting and pyrolysis on lignite slurryability

    GAO Jingjing;CHU Mo;LYU Hailong;ZHAO Man;YANG Xiaomin;School of Chemical and Environmental Engineering,China University of Mining and Technology( Beijing);

    To improve the slurryability of lignite,taking Xinjiang lignite,lignite semi-coke and briquette semi-coke as raw material,compare their slurryability. The results show that the optimum gradation of semi-coke is that the mass ratio of coarse powder and fine powder is 6∶ 4,the best dosage of additives is 1. 2%,the greatest coal water mixture( CWM) concentration is 60. 1%,the apparent viscosity is1153 mPa·s. Under the same gradation and additives dosage,the greatest CWM concentration of lignite and semi-coke are 48. 7% and56. 8%. Proximate analysis and the surface structure research of coal sample show that the moisture and volatile of Xinjiang lignite,semi-coke and briquette semi-coke decrease,fixed carbon increase,the pore radius decrease,specific surface area increase,pore volume change is not obvious with the increase of upgrading modification. So for lignite,upgrading and modification can improve the degree of coalification and slurryability,make the structure more close,decrease the porosity.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 268K]

  • Preliminary exploration of extracting phenolic compounds in medium and low temperature coal tar by glycerin solution

    ZHAO Yuan;MAO Xuefeng;ZHANG Xiaojing;HUANG Peng;DU Shufeng;GU Xiaohui;Beijing Research Institute of Coal Chemistry,China Coal Research Institute Co. ,Ltd.;State Key Laboratory of High Efficient Mining and Clean Utilization;

    Glycerin solution is determined as extractant phenolic compounds in medium and low temperature coal tar by the screening of organic solvent. Take 170 ℃ to 240 ℃ of medium and low temperature coal tar as extraction material. Drawing a conclusion through single factor analysis and orthogonal test. Glycerin addition has the most important influence on extraction rate and it is followed by residence time,water addition and temperature. The optimum extraction condition is that,the mass ratio of glycerin to material is 3∶ 1,the water content of glycerin solution is 5%,the temperature is 30 ℃,the mixing time is 30 minutes. The single-stage extraction rate is up to 92%.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 265K]

  • Optimization of methanol double-effect distillation system

    NING Limin;LI Guozhong;SHAN Junjie;Tangshan Zhongrun Coal Chemical Industry Co. ,Ltd.;

    The methanol double-effect distillation system is simulated and analyzed with the process simulation technology. The optimization scheme is proposed on the basis of the simulation data and the actual condition. The results show that,the simulation production of350. 4 t /d is in accordance with the actual production of 350 t /d. The Wilson in activity coefficient model is used for the simulation. The simulation study show that the methanol double-effect distillation system of steam required amount is 9. 83 t /h,and the use of steam in actual operating condition is 12. 2 t /h,the steam practical usage is still too large. The optimum reflux of the pressured distillation tower 1.50 through simulation study,and the optimum reflux of distillation tower is 0. 94. The twenty-fifth tower plate in the pressured tower is the sensitive plate,the eighteenth tower plate and the thirty-eighth tower plate in the atmospheric distillation tower is the sensitive plate. The temperature above the tray should be focused on daily operation index.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 301K]

  • Quality evaluation of coking coal and problem analysis

    ZHOU Jinhui;DING Ling;College of Chemical Engineering and Technology,Wuhan University of Science and Technology;Hubei Coal Conversion and New Carbon Materials Key Laboratory;

    To improve the accuracy of coking coal quality evaluation,analyze relevant evaluation methods from the aspects of coking coal washability,chemical features,technological characteristics,coal rock characteristics,marks determination,data compilation,expert system.Point out that,the accuracy of evaluation can be improved by optimizing expert system,sampling and preparing operation,measurement instrument accuracy,strengthening the application of coal rock parameters and data statistics. Through above methods,the coking coal can be used properly and the coke quality can be promoted steadily.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 120K]

  • Simulated distillation curve of medium and low temperature coal tar

    QI Wei;WANG Shiyu;Beijing Research Institute of Coal Chemistry,China Coal Research Institute;National Energy Technology and Equipment Laboratory of Coal Utilization and Emission Control( China Coal Research Institute);State Key Laboratory of High Efficient Mining and Clean Utilization of Coal Resources( China Coal Research Institute);

    Translate the simulated distillation curve of medium and low temperature coal tar into theanalogous actual boiling point distillation curve using the analysis function of Origin software. By taking the derivatives of the simulated distillation curve,obtain the analogous actual boiling point distillation curve,which is similar to the actual boiling point distillation curve and shows the relationship between the boiling point and relevant substance content. The curve indicates that as temperature increase,the light component decrease,the heavy oil increase,and the asphalt content increase from 30% to 50%. There are some peak wave of the analogous actual boiling point distillation curve between 350 ℃ and 420 ℃,and the relevant substance content is less in turn with the increase of coal sample terminal pyrolysis temperature. The main reaction of low temperature pyrolysis is depolymerization,high temperature and high energy is good for breakage of high bond energy link,low temperature and low energy is good for breakage of low bond energy link.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 264K]

  • Combustion characteristics of Shenhua coal boiler under low NO_x combustion

    YANG Ming;GU Hongwei;LI Xiaowei;LIU Jiali;Shenhua Group Co. ,Ltd.;Xi'an Thermal Power Research Institute Co. ,Ltd.;

    The ignition and burn-out properties of Shenhua coal are very well,and its nitrogen and sulfur content is very low,which allows the Shenhua coal boiler use low oxygen and large-scale low NOx combustion techniques to obtain high economic benefits and to make low NOx emission. The low content of sulfur characteristic of Shenhua coal can make sure that the H2S content is not high and there is no obvious high temperature corrosion tendencies in the boilers under hypoxic conditions. Under low NOx combustion,the combustion intensity of the burners zone can be reduced,the slagging in the boiler can be alleviated,and the blending proportion of Shenhua coal is increased. Some boilers can use total Shenhua coal while they could not before. Using low oxygen technique combined with low NOx combustion technology can make sure that the Shenhua coal boiler has better economy and security,and lower NOx emission than other typical bitumite boilers. The research shows the advantages of Shenhua coal and also provide technology support for Shenhua coal boilers under low NOx combustion in domestic.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 242K]

  • Influence of heating rate on mixed coal sample pyrolysis and dynamic analysis

    WANG Ruijie;SONG Changzhong;JIN Zhenyi;LI Rong;LI Yuyin;DAN Hong;College of Energy and Power Engineering,Inner Mongol University of Technology;

    In order to save steam coal and reduce power cost,and to provide theoretical guidance for the boiler combustion,the pyrolysis test was carried out on lignite and coal gangue using thermogravimetric analysis and different thermal analysis. Get different situations of TG curves,DSC curves and conversion rates curve by changing the heating rate. The mass ratio of lignite to coal gangue is 2∶ 3,the heating rate is 10 ℃ /min,30 ℃ /min,50 ℃ /min. The heat releasing areas of the coal sample are close when the heating rate is 10 ℃ /min,50℃ /min,while the heat releasing area is small when the heating rate is 30 ℃ /min. The results show that,30 ℃ /min is not suitable for heat releasing. The dynamic analysis show that,the activation energy,frequency factor,pyrolysis kinetics parameters change as the heating rate changes.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 305K]

  • Influencing factors of coal tar yield and quality from low-temperature coal pyrolysis

    MIAO Qing;ZHENG Huaan;ZHANG Shengjun;LI Xueqiang;CHEN Jingsheng;ZHANG Zhigang;Shaanxi Coal and Chemical Technology Institute Co. ,Ltd.;State Energy Key Laboratory of Clean Coal Grading Conversion;

    Coal tar,the main product of low-temperature coal pyrolysis,is an essential chemical material. The yield and quality of coal tar is an important indicator to evaluate the pyrolysis. Investigate the influencing factors of coal tar yield and quality from the aspects of raw coal characteristics such as coal types and coal particle size,structure of pyrolysis reactors and technical conditions including raw coal pretreatment,reaction temperature and pressure,heating rate,gas residence time,reaction atmosphere and catalysts. The results show that the yield and quality of coal tar can be improved by using proper coal and pyrolysis reactors,choosing appropriate technical conditions,adopting catalytic hydrogenation pyrolysis and the like.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 200K]

  • Comparison of combustion characteristics between forest-based and straw-based biomass pellet

    ZHU Fudong;Jiangsu Donggong Biomass Energy Research Institute Co. ,Ltd.;

    Larch and korean pine were used as forest-based biomass pellet,cotton and corn straw were used as straw-based biomass pellet. Burning characteristics,pollutants discharge and bottom ash slagging characteristics of four biomass particles were analyzed with the biomass pellet burner developed by Jiangsu Donggong Biomass Energy Research Institute Limited Company. The results show that the lower moisture,ash content and the higher volatile matter,the shorter the ignition time. The forest-based and straw-based biomass pellet can full combustion during the running stage,and concentration of CO emission is the smallest,the emission of NOxin flue gas concentration is lower than the national standard,the NOxemission concentration is proportional to the content of N,the formation of NOxis mainly the fuel type reaction mechanism. The higher the softening temperature,the lower the slagging rate. There is no evidence of slagging when the softening temperature is above 1390 ℃.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 339K]

  • Characteristics of large circulating fluidized-bed boiler in high altitude area

    ZHANG Shixin;WANG Pengli;GAO Hongpei;HAN Ying;ZHAO Pengbo;JIN Senwang;LIU Haifeng;LIU Dong;Huaneng Clean Energy Research Institute Co. ,Ltd.;

    Based on the start debugging of 4 × 480 t /h circulating fluidized-bed( CFB) boiler in heating center of Qinghai Saline Lake Industrial Co.,Ltd.,through theoretical analysis and practical application,research the characteristics of large circulating fluidized-bed boiler in high altitude area. Resolve the coking problem of high load boiler. Point out the normal operation of fluidized-bed boiler to maintain the fluidization wind speed range. The calculation of fluidization wind speed should choose standard state air flow velocity in high altitude area,which is in accordance with the calculation in the low altitude. The technique has practical reference and operability.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 248K]

  • Coal-electricity-chemical integration cascade efficient utilization of lignite in Eastern Inner Mongolia

    YAN Aihua;Research Center of State Administration of Work Safety P. R. C;

    Eastern Inner Mongolia is abundant in lignite resources,while its utilization is quite simple and inefficient. Taking a surface coal mine in Eastern Inner Mongolia as research object,a new way of lignite coal-electricity-chemical integration cascade efficient circular utilization is proposed. Specifically,lignite is exploited by surface mining,then by drying and low temperature carbonization,high calorific value semi-coke,coal tar,natural gas are produced. Finally,gasoline,diesel,naphtha and other products are generated by liquefaction hydrogenation. Semi-coke is used for power generation. All of above are the basis for building a circular economy industrial system which achieves energy saving and environmental protection. The project has better economic benefits,its successful implementation can change the way of lignite utilization and provide theoretical basis for large-scale lignite integrated utilization.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 328K]

  • Energy performance contracting in marketization of industrial pulverized coal boiler

    JI Renshan;China Coal Research Institute;National Energy Technology and Equipment Laboratory of Coal Utilization and Emission Control( China Coal Research Institute);State Key Laboratory of High Efficient Mining and Clean Utilization of Coal Resources( China Coal Research Institute);

    In order to explore the reasonable management mode of pulverized coal fired industrial boiler island,introduce the profiles of industrial boilers and the new technology system of pulverized coal industrial boilers island and the basic theory of energy performance contracting( EPC). At the same time,the energy saving effects,other practical application effects,economic projects,risk analysis and control of contract in pulverized coal fired boiler in the specific application and EPC model bring to the market advantages of efficient pulverized coal fired boiler were analyzed by cases. The results show that the EPC model is suitable,effective mode for the popularization of efficient pulverized coal boiler,which provides a successful case for the commercialized and industrialized of other high-tech energy-saving products. Building an energy performance contracting alliances,which provides a good exchange platform for the development of the parties involved in a project,and it is the future trend.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 112K]

  • Mercury removal from flue gas by lignite activated coke

    BAI Zhonghua;SHI Yawei;ZHANG Xuhui;YANG Wenhui;ZHANG Xiangzhou;SHI Changjiang;ZHAO Yubing;Energy Management and Environmental Protection Company of ,NARI Group Corporation;State Grid Electric Power Research Institute;Beijing Guodian Futong Science and Technology Development Co. ,Ltd.;Qinghai Electric Power Design Institute;S. Y. Technology Engineering and Construction Co. ,Ltd.;

    Coal-fired power plant mercury pollution has attracted a growing concern,now the current mercury removal method which has an application prospect is the adsorption of mercury removal,and therefore the development of cost-effective mercury removal sorbent been studied extensively. An experiment was conducted to study the effects of lignite activated coke on the mercury adsorption using a bench-scale fixed bed,including the inlet concentration of mercury pollutants,the quality of adsorbent,the composition of flue gas and the type of adsorbent and so on. The results show that the lignite activated coke has some adsorption capacity for mercury in flue gas,the activated coke adsorption rate increases with the increase of entrance mercury concentration and the quality of activated coke. The SO2,NO in flue gas can improve mercury adsorption capacity of activated coke. Although the mercury adsorption capacity of activated coke is lower than activated carbon with S solution and activated carbon only for mercury adsorption,the improvement of activation way of activated coke can enhance the performance of its mercury adsorption.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 412K]

  • The removal of Fe~(2+) in acid coal mine water

    FAN Zewen;HE Liping;XU Ximeng;LI Zongquan;LI Canting;HUANG Mei;Zhenxiong Environmental Research and Monitoring Station;Yunnan Institute of Environmental Sciences;Chemical and Biological Technology,Yunnan University of Nationalities;

    In order to increase the removal efficiency of Fe2+ in acid coal mine water,the coagulant sedimentation without aeration oxidation was carried out to treat acid coal mine water. The effects of pH value and coagulant dosage on the Fe2+ removal efficiency is investigated.The results show that,the Fe2+ removal rate reaches 99. 88% when the pH value is 8. 5 which is adjusted by 5% lime emulsion. So 8. 5 is the optimum pH value. First add 1 mL 0. 1% PAM to the acid coal mine water,then adjust the pH value to 8. 5 by 5% lime emulsion. At last,add 30 mL 0. 1% PAC. The removal efficiency of Fe2+ can reach 100% and the suspended solids can be removed easily. The appropriate pH value and flocculants dosage can remove Fe2+ in acid coal mine water efficiently.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 126K]

  • Utilization technology integrated evaluation model of coalbed methane

    AN Bin;HAN Haitao;MAO Qingguo;Beijing Research Institute of Coal Chemistry,China Coal Research Institute Co. ,Ltd.;Xinwen Mining Group Co.,Ltd;Nanjing Design and Research Institute Co. ,Ltd. ,China Coal Technology and Engineering Group;

    To evaluate the economic value of coalbed methane under different technical economic conditions,taking the utilization technology of coalbed methane as research object,build a synthetic evaluation model involving technological,economic and environmental factor.The model is mainly quantitative evaluation,supplemented by qualitative evaluation. Moreover,discuss the calculation methods of two grade index,three grade index and integrated index. The built of model has great significance for the theoretical research and actual development of coalbed methane.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 165K]

  • Experimental study on deoxidization of coalbed methane with non-catalytic combustion method

    ZHANG Keda;WANG Peng;DONG Weiguo;TANG Nan;LI Xiaoliang;Beijing Research Institute of Coal Chemistry,China Coal Research Institute;Beijing Key Laboratory of Coal Based Carbon Materials;

    Low heat value and concentration of coalbed methane make it can't meet the requirement of industry utilization. So it should be concentrated. The oxygen in coalbed methane increases dangers for concentration process. So it is necessary to remove oxygen from the gas before concentrating. Several deoxidization methods of coalbed methane are briefly represented,and experimental study on the deoxidization of coalbed methane with non-catalytic combustion method in a deoxidization reactor is carried out. The results show that the concentration of oxygen can be reduced to less than 1% with non-catalytic combustion method. The fuel used for deoxidization should have the characteristics of good reactivity and low calorific value. The loss rate of methane is less than 5%,while the deoxidization temperature is close to600 ℃,the pyrolysis of methane is the main reason of methane loss.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 441K]

  • Comprehensive utilization of alumina extraction from fly ash

    YANG Lei;CHI Junzhou;WANG Yongwang;CHEN Dong;ShenHua Zhunneng Resources Comprehensive Development Co. ,Ltd.;

    Discuss the necessity of extracting alumina from fly ash from two perspectives which are the dangerous of fly ash to environment and the current situation of China's bauxite resources. Then,describe the latest technologies and research progress in extracting alumina from fly ash with alkali,acid method,combined method and step by acid digestion method. The results show that the last method has short technological process,low raw material consumption and production cost,and in the production process,there is almost no secondary pollutants. The technology is more suitable for high aluminum ash. Finally,summarize the current application of fly ash and calls for doing more work on studying the utilization of fly ash.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 109K]

  • Environmental management of coal industry in Western China and suggestions

    QIAO Jiao;LI Jia;CHEN Hongbo;Assessment Center of Environmental Engineering,Ministry of Environmental Protection;

    With the changes of coal development layout in China,the environment of western region affected by the coal development is highlighted further. It also produced a series of problems,such as soil erosion,ground subsidence,groundwater damage and the like. In order to further understand the current situation of coal exploitation in western area,environmental protection measures,achievements,existing problems and development of environmental impact to the typical region of coal projects,through collecting the basic situation of coal projects in the western region development and environmental management in recent years,analyse the main environmental problems in the coal industry in western area,from the angle of environmental management,put forward the development of ecological red line index,optimize the layout of coal development,develop project EIA and implementation of environmental protection acceptance check by stages,perfect the compensation mechanism of ecological environment restoration countermeasures. The analysis provides reference for strengthening environmental management of coal industry in western regions.

    2014 04 v.20;No.92 [PaperDigest][OnlineView][Download 105K]