2018年01期目次

  • Mechanism of coal slime conditioning and equipment development history and industrial application

    MA Liqiang;SUN Xianfeng;HUANG Gen;YU Yuexian;School of Chemical and Environmental Engineering,China University of Mining and Technology(Beijing);

    Coal slime conditioning is an important link before flotation.In order to get a comprehensive understanding of coal conditioning,the mechanism and development history of coal slime conditioning in China were elaborated.Bench-scale test and industrial application of BGT surface-modification conditioning machine were stated to analyse the effect of coal slime conditioning. The main mechanisms of coal slime conditioning includes reagent dispersion,effective collisions between particles,reagents and surface cleaning.The development of coal slime conditioning equipment has gone through from the simple mixing tank to further enhance pulp preparation tank,pulp pre-processor,and then to surface modified slurry machine which has better mineralization. The data of laboratory and industrial tests illustrates that strengthening the conditioning can dramatically improve the coal flotation effect.Sufficient conditioning plays a key role in flotation.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1276K]

  • Research progress on extraction technology and application of lignite humic acid

    ZHANG Chuanxiang;ZHANG Xiaoming;CHENG Gan;College of Chemistry and Chemical Engineering,Henan Polytechnic University;Collaborative Innovation Center of Coal Work Safety;Henan Key Laboratory of Coal Green Conversion;

    Industrialized application of lignite is restricted,due to its high moisture content,low calorific value and poor stability.However,lignite coal contents highly humic acid,and the extraction of humic acid has high biochemical activity,which has been widely used in the fields of agriculture,medicine,environmental protection and other fields.In this paper,the research progress and application on humic acid extraction were reviewed.The process and mechanism of extraction of humic acid by alkali extraction,acid extraction,microorganism were emphatically described.The preparation of the green,stable,low price,high yield humic acid,and its application expansion are the research priority of humic acid.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1324K]

  • Research status and industrial direction of middle and low temperature coal pyrolysis technology

    ZHENG Huaan;State Energy Key Laboratory of Clean Coal Grading Conversion;

    For the rapid development of coal pyrolysis,characteristics and present situation of pyrolysis were elaborated,and methods were proposed for solving problems of pyrolysis technology.At last,future development direction of pyrolysis was forecasted. Coal pyrolysis is an effective path to make the transformation of coal from raw material to raw material and fuels due to its advantages,such as efficiency and clean process,various high-quality products and fully utilization of resource. Based on analysis of principle,technology,product structure and quality,economy and environmental protection,low rank coal is suitable for pyrolysis,and pyrolysis technology is new engine for promoting further development of modern coal chemical industry.Future development direction of pyrolysis technology are to realize the cleanliness,commercialization and high added value of pyrolysis products,to upgrade equipment scale andintegration level of automatic control system,to realize organic fusion of pyrolysis technology and modern coal chemical and petrochemical systems,to increase the application innovation of supporting environmental protection and energy saving technology.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1244K]

  • Performance evaluation and technical status of the small coal furnace

    CHENG Fangqin;PENG Hao;WU Haibin;JIA Yangjie;YANG Fengling;Institute of Resources and Environment Engineering,Shanxi University;State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste Resources;Shanxi Rui En Ze Technology Co.,Ltd.;

    In order to solve problems from coal furnace like high pollution emissions,low thermal efficiency and incomplete combustion,the structure,research status,application and pollutant evaluation methods of small coal furnace at home and abroad were studied. In view of the current living habits and economic conditions of small towns and rural residents in northern China,a kind of environment-friendly coal furnace( NQ-18 C) was designed,which was compared with ordinary boilers in combustion efficiency and pollutant emission. The results show that the heating capacity of NQ-18 C is 1.89 times of that of ordinary boiler,the thermal efficiency is over 65%,the temperature of exhaust gas is 200 ℃,the fly ash and slag carbon content is 6.4%,which conforms to the national standard GB/T 16155—2005.When burning environment-friendly coal,SO_2 and NO_xemissions are less than 200×10~(-6) and 300× 10~(-6) respectively with high combustion efficiency and safe and stable operation.NQ-18 C can suppress NO_xand eliminates black smoke emissions.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1629K]

  • Status and development trend of coal-based activated carbon production technology in China

    JIANG Yu;LIU Deqian;XIE Qiang;School of Chemical and Environmental Engineering,China University of Mining and Technology(Beijing);Datong Coal Mine Group Co.,Ltd.;

    Activated carbon has been widely used in the field of environmental protection,especially the coal-based activated carbon used in water treatment has become the main product of activated carbons.A critical review on status of technology and equipment for coal-based activated carbon production was presented. In addition,the approaches to regulating pore structure of coal-based activated carbon were summarized.Finally,the development trend of coal-based activated carbon industry was briefly analyzed.The results show that with the popularization of the preparation technology of activated carbon by briquetting method and application of multiple hearth furnace,production of coal-based activated carbon on large scale becomes a reality and it is possible to prepare diversified and specialized coal-based activated carbon by coal blending,introducing additives in raw coal and optimizing carbonization and activation process parameters.

    2018 01 v.24;No.113 [Abstract][OnlineView][Download 1680K]

  • Technical progress of underground mine water treatment and zero discharge of waste water

    GUO Qiang;State Key Laboratory of Water Resources Protection and Utilization in Coal Mining;

    In order to solve the problems of low utilization rate of coal mine water and environmental pollution,and to promote the treatment and utilization of mine water,the basic principle,process route,technical characteristics and project cases of underground mine water treatment technology were discussed.Aimed at the question of underground mine water treatment,the solutions were put forward,and the prospect was prospected.The results show that high-density sedimentation,super-magnetic separation and goaf filtration technology can achieve high efficiency and low cost removal of suspended solids,the membrane treatment and low temperature multi-effect evaporation technology can be widely used in mine water desalination,the underground coal reservoir storing concentrated salt wastewater is an effective way to achieve zero discharge of mine water treatment wastewater. It will be the development tendency and direction of underground mine water treatment and utilization that includes to develop efficient,modular and mobile processing units for the underground space,to enhance explosion-proof performance of the processing unit,automatic control performance and safety monitoring performance,to achieve mine water treatment and quality classification with a variety of processing techniques.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1268K]

  • Effect of coal group components on pyrolysis fluidity of raw coal and its mechanism

    BU Lianghui;QIN Zhihong;LI Xiang;School of Chemical Engineering and Technology,China University of Mining and Technology;Key Laboratory of Coal Processing and Efficient Utilization ( Ministry of Education) ,China University of Mining and Technology;

    Y_(DMC)、Y_(LMC)、Y_(HC)、Y_(LC) and (a+b)_(LMC) were related to lg F_(wa) by means of multiple linear regression in order to study the relationship between coal group components and their pyrolysis characteristics with pyrolysis fluidity of raw coal.Stepwise regression analysis was used to explain selection of variables and mechanism of different group components on the fluidity of raw coal was clarified from the component and structure of coal group components standpoint. Results show that heavy component plays a skeleton role in raw coal and it is the main component hindering the fluidity of raw coal.Content of heavy component is the decision factor affecting the fluidity of raw coal.Content of dense medium component only plays an auxiliary role in the fluidity of raw coal although the dense medium component is the main component to promote the fluidity of raw coal.Moderate dense medium component is necessary to produce moderate fluid phase to play a lubrication role.There is synergistic effect between dense medium component and heavy component,which determins the fluidity of raw coal,while light component and loose medium component have no significant influence on the fluidity of raw coal.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2080K]

  • Feasibility study on reverse flotation of pyrite and coal by plasma pre-treatment

    ZHU Ziqi;School of Chemical Engineering and Technology,China University of Mining and Technology;Shengdong Coal Group Select Center;

    In order to increase the floatability difference between pyrite and coal,the idea of using low-temperature air plasma modification was put forward.SEM,EDS,XPS and contact angle were carried out to measure the surface property of pure pyrite before and after plasma treatment.SEM detectes that the surface of pyrite changed is little,while the surface morphology of organic matter change drastically with the number of cracks,depth and width increase significantly.XPS results show that the content of O increases gradually and the content of S decreases on the surface of pyrite.While,the content of O increases gradually and C decreases on the surface of organic matter.Moreover,the content of C—C,C—H decreased and C—O,COO— increases sharply. The contact angle and flotation test results indicate that the difference of contact angle between pyrite and coal treated for 1-5 min increases by 3.5-9.7 times.The floatation yield of pyrite and organic matter decrease when treated with flotation alone,and the yield of organic matter significantly reduce. The plasma modification significantly expandes the difference between pyrite and organic matter,and it is feasible to inhibit the reverse flotation of coal.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2547K]

  • Pilot plant study on 240 t/d pulverized coal pyrolysis technology with solid heat carrier

    JING Xuye;WANG Kun;DONG Pengfei;MENG Guangjun;ZHU Zhiping;LYU Qinggang;Institute of Engineering Thermophysics,Chinese Academy of Sciences;University of Chinese Academy of Sciences;

    Taking the cascade utilization of pulverized coal as the background,a pulverized coal pyrolysis technology with solid heat carrier was proposed in this study.The proposed technology mainly includes the pyrolysis-gasification coupled system based on circulating fluidized bed,the system for removing coal ash and waste heat recovery from gasification gas and the system of deashing,purification and separation for pyrolysis oil-gas. The pilot plant of this technology has achieved a continuous and stable operation for 72 hours at the end of 2016.In the pilot experiment,the coal of 0-10 mm was used as the raw material and the feed amount of raw coal was a full load of 240 t/d.The experimental results show that the volume content of CH_4 and H_2 in the pyrolysis gas are 35. 3% and 12. 5%,and the calorific value of the pyrolysis gas is over 20 920 kJ/Nm~3; the yield of pyrolysis tar is 9. 24%,which is 81. 8% of the Gray-King tar yield of raw coal; the dust content of the product tar is 0. 47%,and the mass fraction of N-heptane soluble in tar is 84. 3%; the fixed carbon content in the pyrolysis semicoke is 86. 3% and the calorific value of the semicoke is 29 985 kJ/kg.For the pilot plant that operated continuously and steadily for 72 hours,the calculated mass balance deviation and energy efficiency are 1. 93% and 87. 95%,respectively.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1954K]

  • Influencing factors of electroflotation-electrocoagulation seperation of coal macerals

    ZHAO Wei;QU Jinzhou;LI Zhen;YANG Zhiyuan;ZHOU Anning;College of Chemistry & Chemical Engineering,Xi'an University of Science and Technology;Key Laboratory of Coal Resources Exploration and Comprehensive Utilization,Ministry of Land and Resources;

    The separation of coal macerals was studied by an electroflotation-electrocoagulation method.The effect of the pH of pulp,voltage intensity,flotation time,pulp concentration and electrocoagulation on separation was investigated.Separation effect was evaluated by the enrichment and recovery rate of the coal vitrinite and inertinite.The results indicate that the pH of pulp,the voltage,flotation time and pulp density can be controlled to adjuste the rate of flotation recovery and enrichment of coal macerals.The flotation separation of coal macerals can be intensified effectively with the electrocoagulation.The effect of the electrocoagulation is controlled by the concentration of aluminum ion in the reaction process,and the higher the concentration of aluminum ions is,the faster the formation rate of flocculation will be.The adjustment of the electrochemical reaction rate of the anode can change the aluminum concentration and its hydrolysis form in the solution and control the effect of flotation separation.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 3240K]

  • Three peak fractal grading coal water slurry concentration technology

    ZHOU Yongtao;China Coal Shaanxi Yulin Energy and Chemical Co.,Ltd.;

    For improving conversion efficiency of coal gasification,principle and characteristics of three peak fractal grading pulping technology were discussed.Single grinder slurry process and three peak fractal grading pulping process were contrasted,which slurryability were analysed through the laboratory research.Based on single grinder slurry unit,industrial demonstration of three peak fractal grading coal water slurry concentration technology was carried out in China Coal Shaanxi Yulin Energy and Chemical Co.,Ltd. Through analysing project feasibility and project technical scheme,operation effect was contrasted before and after operation. The results show that coal water slurry concentration is only 61. 4% with unreasonable grain size distribution and bad fluidity and stability in condition of single grinder and 0. 18% ZM additive.In three peak grading process,when the best three peak particle size ratio is 85 ∶ 10 ∶ 5,coal water slurry concentration can increase to 65.5% which increases by 4.1% than single grinder slurry.At the same time,liquidity and stability of coal water slurry are improved significantly.Industrial operation results show that in the same conditions,coal water slurry tank slurry concentration becomes from 61.7% to 65.5%.Coal and oxygen consumption of 1 000 Nm~3 CO+H_2 are reduced by 40.76 kg and 33. 44 Nm~3,and synthesis gas content is increased by 1.48%.Quality and gasification efficiency of gasified coal water slurry have been significantly improved with three peak fractal grading technology.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1530K]

  • Research on jet-stirring coupling coal slime flotation device

    ZHU Jinbo;HAN Youli;FEI Zhikui;WANG Chao;ZHOU Wei;ZHU Hongzheng;WANG Hainan;ZHANG Yong;FENG An'an;School of Materials Science and Engineering,Anhui University of Science & Technology;

    Froth flotation is an effective separation method for fine minerals.Incorporated the principle of the flotation equipment with less power consumption,high energy conversion,two new types of flotation devices were designed by coupling jet technology.The effect of jet inspiration and stirring inspiration on particle size distribution of bubbles,bubble mineralization and flow field uniformity were researched.Jet inspiration and stirring inspiration aare combined in the Ⅱ type,which can realize large inspiratory capacity,uniform distribution of bubble size and stable flow field.The Ⅱ type is able to get large inspiratory capacity and uniform three phase flow field under the lower energy consumption and lower speed.The energy transformation and flotation efficiency are affectd by operating mode and structural parameters,such as inflow pressure,gas-liquid ratio,nozzle spacing,section ratio and so on. The flotation device achieves the purpose of pretreatment and flotation.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1294K]

  • Effect of technological conditions on residence time of coal particle in internal rotating reactor

    MA Dong;LI Wenbo;PEI Xianfeng;BAI Xiaoyan;China Coal Research Institute;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 provide theoretical guidance for the residence time and mixing effect of particles in the internal rotating reactor,the characteristics of residence time distribution( RTD) of coal particle as filling materials and tracers in an internal rotating reactor were investigated with the pulse method.The condition parameters tested included the length of the shaft,shaft speed,particle size and feed rate etc.The results show that the back mixing exists in the reactor with 60° propeller blades for the appearance of large trailing distance and the peaks at rear of average RTD curve.The particle flow pattern in the reactor lies between the ideal plug flow and completely stirred flow.The relationship between average residence time and the length of rotating shaft is linear,which is exponential with the rotating speed.Axial mixing is intensified and the average residence time are shortened by increasing speed.With the increase of coal particle size,both the average residence time in the reactor and the degree of the axial backmixing decrease.In addition,some lager particles would be broken during the transportation process,and percentage of particle breakage of 5-6 mm coal particles is 35.39%.Maintaining a constant rotating speed,the feed rate changes the amount of filler in the reactor and further influenced the RTD,as well the average residence time decreases with the feed rate.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2421K]

  • Differences between Xinjiang and inland coking coals

    WANG Feng;WU Qiang;ZHU Zizong;SHI Guojing;BAI Dayong;College of Material Science and Engineering,Chongqing University;Xinxing Ductile Iron Pipes Co.,Ltd.;

    Xinjiang has abundant coking coal resource,but Xinjiang coke used by Xinjiang coking coals exhibits high reactivity and low strength after reaction.So it is difficult to translate effectively the resource advantage of Xinjiang into cost advantage.In order to obtain the specificity of Xinjiang coking coal,four typical Xinjiang coking coals and another four inland coking coals of same rank were studied by coal properties analysis,vitrinite reflectance analysis and FTIR analysis. The results show that the differences between low-rank Xinjiang coking coal and low-rank inland coking coal are not obvious.Ash and sulfur content of medium-rank Xinjiang coking coal are lower than medium-rank inland coking coal,which is benefit for decreasing ash and sulfur content of coke.Furthermore,medium-rank Xinjiang coking coal has relatively lower mean maximum vitrinite reflectance,maximum thickness of plastic layer and aromatic condensation in comparison with medium-rank inland coking coal,while the amount of branched aliphatic side-chains and hydroxyl of medium-rank Xinjiang coking coal is higher than medium-rank inland coking coal.It indicates that metamorphism degree of medium-rank Xinjiang coking coal is lower than that of medium-rank inland coking coal.The similar phenomenon is also observed in high-rank Xinjiang coking coal.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2115K]

  • Evaluation of coal/char gasification reactivity under condition of entrained flow coal gasification

    HUANG Yuyi;XIE Qiang;School of Chemical and Environmental Engineering,China University of Mining and Technology(Beijing);

    In order to establish a method for evaluating gasification reactivity suitable for entrained flow gasification,an index,H_(PO) ,is proposed with the aid of a gasification apparatus similar to the modern coal gasification process.The validity of H_(PO) on the gasification reactivity of coal/char was verified according to the gasification experimental data of the typical coal/char samples.The results show that the CO_2 concentration after gasification or/and CO_2 reduction ratio are not capable of evaluating the gasification activity of coal/char accurately;whereas the H_(PO) can avoid interference from gasifiable components and quickly and accurately assess the coal/char's gasification reactivity under entrained flow condition.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1151K]

  • Experiment on the performance of complexation extraction process

    WANG Jikun;DU Song;Coal Science and Technology Co.,Ltd.;State Key Laboratory of Coal Mining and Clean Utilization;

    In order to obtain the optimum technological parameters of phenol complexation extraction process,the extraction experiment was carried out using 40% TOA-60% kerosene as complexing agent.The effect of different factors on the removal of phenol was determined by single factor experiment,and the effect of different factors on the extraction efficiency was studied through orthogonal experiment. Finally,the optimal process parameters were obtained. Extraction efficiency was achieved under the optimal process parameters. The results show that the phase ratio will be increased when the extraction rate increases,and pH and temperature decrease.The influence of the 4-step conditions on the extraction rate is extraction rate >the phase ratio >pH> temperature.The best process parameters can be achieved when the extraction series is four grade,phase ratio is 1 ∶ 3,pH is 4,the temperature is 25 ℃,and the total phenol extraction rate is 94%.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2660K]

  • Separation of phenolics-aromatic hydrocarbons-naphthenes from low-rank direct coal liquefaction oil

    FAN Wenjun;CHEN Pengju;FENG Jie;LI Wenying;Training Base of State Key Laboratory of Coal Science and Technology Jointly Constructed by Shanxi Province and Ministry of Science and Technology,Taiyuan University of Technology;

    In order to explore the method of direct coal liquefaction( DCL) oil fraction separation and to optimize the separation system to fit the whole liquefaction system.The 180-200 ℃ fraction of DCL,which contained the typical components of phenol,aromatic and cycloalkanes compounds,were chosen as the liquid-phase separation target. By using the triethylene glycol and sulfolane as the extractants solvents,DCL fraction were studied and thermodynamic data was used to build a separation system that included the extractive distillation unit following with extraction unit.The results show that the simulation of combined separation system can archive the purity of aromatic compounds 79.94%,paraffin 81.15% and crude phenol 95.75% respectively,the yield of crude oil recovery is 99.23%.The analysis of energy consumption indicate that the phenol removal process contributes to the most 68.66% of the total energy consumption.The modified separation process can save 70.53% of energy consumption through minimizing the amounts of extractant solvents,and the unit product energy consumption decreases 46.67%.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2790K]

  • Effect of calcination parameters on the reaction performance of pyrite cinder in chemical looping combustion

    LI Yanbing;Shenhua Guohua(Beijing) Electric Power Research Institute Co.,Ltd.;

    Calcination process of oxygen carrier is the premise of its application in chemical looping combustion system,which is critical for the influence of its reaction characteristics.Pyrite cinder was applied as the candidate of oxygen carrier,the comprehensive influence of critical calcination process parameters( calcination heating rate,calcination temperature and calcination duration time) on the reaction performance of pyrite cinder was investigated,orthogonal experimental design was used for the optimization of calcination process parameters.The study shows significant difference in the effect of three calcination parameters on the reaction performance of pyrite cinder oyxgen carrier,in which the calcination temperature shows the greatest impact,the pyrite cinder with the best performance is obtained at calcination heating rate of 15 ℃/min,calcination temperature of 1 050 ℃ and calcination duration time of 60 min,therefore it is more suitable for high-purity CO_2 capture in chemical looping combustion.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 3871K]

  • Optimize flexibility of four-angle cut round anthracite boiler combustion system

    XIONG Yingying;TAN Houzhang;Department of Power Engineering,Shanxi University;Laboratory of Thermo-Fluid Science and Engineering,Ministry of Education,Xi'an Jiaotong University;

    In order to solve problems in the anthracite boiler combustion,such as poor ignition performance,low burnout rate,unstable combustion of boiler,efficiency decline,large area of heating surface and so on.Optimize flexibility of combustion system in a 220 t/h anthracite boiler was researched.Influence of coal powder fineness,boiler load,coal mill start and stop,tertiary air,secondary air,gas and other factors on coal fire was studied in thermal test.Tertiary air,secondary air and primary air were obtained,and tie-floating test,hearth and wall velocity were studied in cold test.Scheme of optimize flexibility in a 220 t/h anthracite boiler is confirmed.Imaginary cut circle size and actual cut circle size are 700 mm and 4 000 mm,respectively.V type of lower primary air is changed from vertical to level,and V-gutter of upper primary air horizontal bias burner is replaced by straight plate.Refractory belt area is adjusted from 80.64 m~2 to 63.36 m~2,and four mashgas flow neter are installed.According to experimental results,calculation formula of actual cut circle size is obtained,and correction factor Kxs is determined to 1.132,moreover,the relationship between actual cut circle and primary air speed,secondary air speed is made.After transforming,test unit reduces boiler heating surface coking maximally,improves operation properties of mixed burning inferior coal,and unburned carbon content is controled to 3.29%.The optimization scheme can be popularized in the flexible transformation of anthracite combustion boiler.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2468K]

  • Combustion process model of gangue and its application in the design of a circulating fluidized bed boiler

    ZHANG Jianchun;HUANG Yiqun;ZHANG Man;LIU Aicheng;YANG Hairui;LYU Junfu;Taiyuan Boiler Group Co.,Ltd.;Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Tsinghua University;

    In order to study the combustion performance of gangue with heat value less than 8.374 MJ/kg in the CFB boiler.The combustion process of coal gangue was investigated by modeling,and the burnout time and resident time of different particle size and varies kinds of coal waste were predicted.The maximum coal gangue particle diameters,bed inventory,pressure of primary air fan were obtained from the prediction.These results were applied in the design of a 220 t/h CFB boiler that purely fired the coal gangue.The 4 years operation proves that the design of the larger section size air distributor,low gas velocity in the riser,stronger momentum secondary air nozzle,higher collection efficiency cyclone,which are based on the model prediction,are reasonable.Coal gangue with heat value about 6.281 MJ/kg,the stable combustion as well as the loading ability achieve.It is found that the boiler could operate stably even with the coal gangue of low calorific value as 3.350 MJ/kg.The primary air pressure in the wind box is 11 kPa,and the bed temperature is 890 ℃ with the gas temperature of 910 ℃ at the inlet and outlet of the cyclone at rated load.The boiler operation thermal efficiency is 79.37% due to the higher heat loss carried by the bottom ash and exhaust flue gas.The loss on ignition of both the bottom ash and fly ash are less than 3%.The emission concentration of SO_2 and NO_x are controlled very low and matches the local policy.The continuous running time is more than three months.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2682K]

  • Synthesis and characterization of high propene selectivity FMTP catalyst

    WANG Qi;MAO Xikang;WANG Xiaolong;YANG Wenwu;XIAO Tiancun;Huaneng Clean Energy Research Institute;State Key Laboratory of Coal-based Clean Energy;Science and Technology Research Institute,China University of Petroleum(Beijing);College of Chemical Engineering,Beijing University of Chemical Technology;

    In order to improve the propene yield and inhibit coking,a synthetic method of hierarchical porous SAPO-34 using in-situ self-etching in phosphoric acid-triethylamine buffer solution was proposed. The synthetic products were characterized through X-ray diffraction,scanning electron microscope and nitrogen adsorption and catalytic testing.Results show that the crystal grows preliminary and it is etched in the H_3PO_4-TEA buffer in a later period resulting in mesopores and macropores,the mesoporous volume of which is as high as 53.7% of micro-mesoporous volume.With the increase of crystallization/etching time,the four side surfaces of the crystal are etched diagonally to etching and non-etching zones,parallelepiped SAPO-34 crystal even becomes pyramid. The in-situ self-etching SAPO-34 achieves 45.5% selectivity of propene,together with the coke selectivity less than 2%,and triple lifetime.This method has been successfully applied in a 2 m~3 stirred tank for industrial scaling-up,and the catalyst is active during 250 min with WHSV of 1.5 h~(-1).

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 3038K]

  • Experimental study on new catalyst in the MTO unit

    SUN Xiaowei;LIANG Xuhui;HAO Yong;LI Jingwei;Shaanxi Yanchang China Coal Yulin Energy & Chemicals Co.,Ltd.;Grace Catalysts (Qingdao)Co.,Ltd.;

    In order to improve the performance of industrial MTO unit,properties of GCQ-NF8 catalyst and reference catalyst were contrasted through lab-scale test.Industrial trial of GCQ-NF8 catalyst were conducted to validate lab-scale test results in industrial MTO unit.Specific area and pore volume of GCQ-NF8 catalyst were determined through N_2 physisorphtion,and size distribution was obtained by laser particle size analyzer.Results show that wear resistance of GCQ-NF8 catalyst is better than reference catalyst,and it meets the requirements of industrial MTO unit.Selectivity of GCQ-NF8 catalyst has an optimum value with reaction time lasting in fluidized-bed reactor.According to the monthly statistics of the product yields during industrial trial,when the average turnover rate of GCQ-NF8 catalyst increases from 14% to 77%,selectivity of light olefin in charge gas increases from 77.72% to 79.78%,and light olefin yield and ethylene to propylene ratio increase to 32.56% from 31.54% and to 1.017 from 0.960 respectively under 110% load.The performance of industrial MTO unit,such as light olefin yield and ethylene to propylene ratio,are improved by applying GCQ-NF8 catalyst.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1558K]

  • Intrinsic kinetics study of sodium sulfite oxidation inhibition

    ZHANG Wenfeng;HUANG Zhanggen;HOU Yaqin;HAN Xiaojin;State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences;University of Chinese Academy of Sciences;

    In order to improve the competitiveness of the dry-integrated desulfurization and denitrification technology,high-concentration SO_2 generated from sulfur and flue gas from coal-fired flue gas was utilized to prepare high-value added sodium sulfite.Kinetic model was used to evaluate the inhibiting effect of different inhibitors valued by Inhibition Power(IP).It was found that the stronger oxidation inhibition effect was brought by adding ascorbic acid during sodium sulfite preparation process.Effects of different factors,including sodium sulfite concentration,ascorbic acid concentration,reaction temperature,pH value,carbonate ions and mercury ions,on sodium sulfite oxidation rate was investigated.The results show that ascorbic acid is a powerful inhibitor. The induction time lasts 90 minutes during the oxidation process in the presence of ascorbic acid and its IP is 7.54×10~8,higher than other inhibitors.Lower p H is benefit to the oxidation inhibition and carbonate ions and mercury ions can weaken the inhibiting effect.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2596K]

  • Adsorption properties and mechanism of coal-based polyaniline to phenol wastewater

    LIU Zhuannian;SHAO Huafan;HAN Xiaogang;FAN Aping;ZHANG Yuanyuan;College of Geology and Environment,Xi'an Uninversity of Science and Technology;

    In order to effectively remove the persistent and refractory organic pollutants phenol in water. Coal-based polyaniline was prepared by lignite coal milled with high energy ball.Various measures such as SEM and FTIR were used to characterize the structure of coalbased polyaniline and raw coal powder.Adsorption properties and mechanism of coal-based polyaniline to phenol solution were studied with raw coal powder as the control experiment.The results show that pore structure and distribution of the coal-based polyaniline adsorbent are better than that of raw coal powder and it has more mesopores and microporous,which is conducive to increase the adsorption capacity.When pH is 4,the removal rate of raw coal powder and coal-based polyaniline are 22.74% and 45.32%,respectively.In acidic conditions,the adsorption effect of the adsorbents on phenol solution are better. The adsorption effect of coal-based polyaniline on phenol solution is better than that of raw coal powder,which optimum dosage is 1 g/L,and the removal rate and adsorption capacity are 45. 32% and 32.52 mg/g,respectively.The adsorption of coal-based polyaniline adsorbent on phenol follows the Lagergren second-order adsorption kinetics model and the Freundlich adsorption isotherm model.Coal-based polyaniline adsorbent has good potential for industrial applications due to its simple preparation procedure and easily available raw materials.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 1846K]

  • Low nitrogen combustion of pulverized coal furnace and SNCR denitration technology

    ZHANG Pan;FAN Xiangzi;Hangzhou Environmental Protection Research Institute of China Coal Technology & Engineering Group;

    In order to solve problems of denitrifying pulverized coal furnace,such as high NO_x concentration and spatial constrains,a 130 t/h boiler of Baogang group thermal power plant was selected to analyze its technical principles and challenges in the denitrifying process,and finally a " low nitrogen combustion & SNCR" process route suitable for denitrifying pulverized coal furnace was proposed with features,such as low nitrogen combustion reconstruction of the main burner,reducing the elevation of the main burner and increasing over fire air outlets at high positions,installing multiple layers of spray guns above the combustion chamber in a scattered layout; using urea as the denitration reducing agent; using high-flow single-hole nozzles.The results show that this process route has an overall denitrifying rate above 70% and keeps the concentration of discharged NO_x below 180 mg/Nm~3,which can effect satisfy the requirements on environmental protection.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2639K]

  • Analysis of flue dust characteristics of 600 MW ultra-low emission coal-fired unit

    ZHAO Bin;GAO Mingfei;WANG Zhen;JIN Shanshan;DONG Changwei;College of Metallurgy and Energy,North China University of Science and Technology;Hebei Electric Power Design and Research Institute;

    In order to develop ultra-low emission reconstruction for the coal-fired power stations in case of current environmental pollution problem.Based on a 600 MW unit,standards and technical methods of ultra-low emission was discussed. The fine particles were sampled from import and export of wet flue gas desulfurization system( WFDG),in order to analyze the emission and component characteristics.The results show that WFGD system has a great removal effect on the large particles in flue gas and the mass concentration of particle size under PM_(2.5) is increased.After desulphurization,the pattern of fine particles is changed from the chain structure to the cluster structure,which the volume is smaller.The main elements of the particles do not change.The content of Ca,Mg and S increase slightly,while the content of Si and Al decrease.Composition of limestone and gypsum is increased in the particles,which is carried out by WFGD system after desulphurization.

    2018 01 v.24;No.113 [Abstract][OnlineView][HTML全文][Download 2234K]



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