Research on the maceral characteristics of Shenhua coal and efficient and directional direct coal liquefaction technology

In this research,molecular structure models were developed respectively for Shenhua coal vitrinite concentrates(SDV)and inertinite concentrates(SDI),on the basis of information on constitutional unit of Shenhau coal and elemental analysis results obtained from^(13)C-NMR analysis characterization,FTIR analysis characterization,X-ray diffraction XRD and XPS analysis characterization.It can be observed from characterization data and molecular structure models that the structure of SDV and SDI is dominated by aromatic hydrocarbon,with aromaticity of SDI higher than that of SDV;SDV mainly consists of small molecule basic structure unit,while SDI is largely made from macromolecular structure unit.Based on bond-level parameters of the molecular model,the research found through the autoclave experiment that vitrinite liquefaction process goes under thermodynamics control and inertinite liquefaction process under dynamics control.The research developed an efficient directional direct coal liquefaction technology based on the maceral characteristics of Shenhua coal,which can effectively improve oil yield and lower gas yield.

粉煤灰中铝、镓、锂回收技术研究进展

粉煤灰是燃煤电厂产生的主要固废,除了富含Al元素,还含有Ga、Li等有价元素,是铝、镓、锂等有价金属的潜在性提取资源。各种粉煤灰回收铝工艺中,传统碱法工艺、碱溶工艺、酸法工艺等还不能达到低能耗、低试剂消耗、低排放、高回收率的要求,其他新型工艺,如水化学法、真空热还原法、碳热氯化法等,具有产渣量少和绿色环保的优点,但仍处于实验室小试研究阶段;粉煤灰中镓和锂的含量相对较低,回收工艺一般采用沉淀法、溶剂萃取法和树脂吸附法,树脂吸附法具有选择性好、环境污染小的优点,但主要用于碱性体系;铝、镓和锂等多元素协同回收是实现粉煤灰资源化利用的重要途径。“一步酸溶法”工艺技术以氧化铝提取为主线,以镓、锂提取和硅铝基材料制备为副线,是目前粉煤灰资源化利用工艺中最具应用前景的工艺。未来,在粉煤灰中有价金属综合回收方面还需要加强以下几方面研究:研发新型的烧结技术,开发硅钙渣的综合性利用途径,彻底解决碱法工艺能耗高和废渣量大的问题;加大无机非金属材料改性的研发力度,解决酸法工艺的设备腐蚀问题;研发廉价的萃取剂和吸附树脂,或开发更加高效的除杂工艺,从而降低酸法工艺的投资成本。

MTO级甲醇合成系统能效优化研究

甲醇生产过程普遍存在能耗、水耗过高的问题,对该系统进行节能研究具有重要的意义。文章通过夹点分析技术,对MTO级甲醇合成系统换热网络进行分析优化,按照避免热流量通过夹点换热、不应有跨越夹点的传热等原则,以及一次换热处理完一股物流的设计经验,对MTO级甲醇合成系统进行能耗方面的优化。以120万t/a煤制甲醇为例,把合成器出口气体分成2股,一股用来加热原料气,一股用来给预精馏塔底提供热量。优化后反应器出口物流经一次换热后温度比原来降低了近30℃,充分利用了甲醇合成反应器出口物流的热能,同时节省0.56MPa低压蒸汽140 t/h,节约循环水量2 770 t/h,节省整个系统单元的蒸汽和循环水量达98.75%,为甲醇合成单元提高能效、降低系统能耗提供一定的参考。

Modeling and optimization of industrial Fischer–Tropsch synthesis with the slurry bubble column reactor and iron-based catalyst

To optimize industrial Fischer-Tropsch （IT） synthesis with the slurry bubble column reactor （SBCR） and iron- based catalyst, a comprehensive process model for IT synthesis that includes a detailed SBCR model, gas liquid separation model, simplified CO2 removal model and tail gas cycle model was developed. An effective iteration algorithm was proposed to solve this process model, and the model was validated by industrial demonstration experiments data （SBCR with 5.8 m diameter and 30 m height）, with a maximum relative error 〈 10% for predicting the SBCR performances. Subsequently, the proposed model was adopted to optimize the industrial SBCR performances simultaneously considering process and reactor parameters variations. The results show that C5＋yield increases as catalyst loading increases within 10-70 ton and syngas H2/CO value decreases within 1.3-1.6, but it doesn＇t increase obviously when the catalyst loading exceeds 45 ton （about 15 wt% concentration）. Higher catalyst loading will result in higher difficulty for wax/catalyst separation and higher catalyst cost. There- fore, the catalyst loading （45 ton） is recommended for the industrial demonstration SBCR operation at syngas H2/ CO = 1.3, and the C5 ＋ yield is about 402 ton＂ per day, which has an about 16% increase than the industrial dem- onstration run result.

Optimization of transport passage with dragline system in thick overburden open pit mine

According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport passage is analyzed in aspects such as the internal dump occupation,dragline operation efficiency,coal transport distance,upper stripping distance and shifting quantities.The middle passage should be given priority in thick overburden open pit mine because the dragline system is only responsible for part stripping task.According to characteristics of middle passage,the transport passage is divided into parallel climbing,vertical climbing and horizontal transport.In addition,the transport passage structure optimization model and shifting distance optimization model are established in this paper.The case study in Heidaigou open pit mine shows that,the parallel climbing height is accounted for about 60%of the total height,and reasonable shifting distances of the first mining area and the second mining area are 240 and 320 m.Sensitivity analysis shows that,the total passage height has important influence on the shifting step,so it is with the stripping height and passage construction cost to the passage structure.

Post-riser Regeneration Technology in FCC Unit

In our present work, a post-riser regeneration technology （PRRT） for fluid catalytic cracking （FCC） units was developed to deal with increasingly heavier feedstock and hereby the larger amount of coke deposited on the catalyst particles during reaction. This technology can make full use of the advantages of riser regenerator, such as high cokeburning efficiency and low residual carbon, and at the same time overcome its disadvantages, such as difficulty in starting combustion. The average particles concentration on the cross section of the system was studied on a large scale cold model experimental set-up. Also a necessary software was developed by combining the hydrodynamics research results in our work with the coke-burning kinetics model and the heat and mass transfer model developed by previous researchers. The simulation results showed that the PRRT could increase regeneration capability by 16.28%-26.24% over the conventional turbulent fluidized bed regenerator under the similar operation conditions, and that the residual carbon could be kept below 0.1 wt %.

A Synergetic Study on Large-Scale Coal Mining and Eco-Environment Protection in Shendong Coal Mining Area

Based on the sharp contradiction between the economic benefits and adverse ecological impact of coal development in China's west,this paper establishes an evaluation model for the synergetic eco-environmental development in Shendong Coal Mining Area through using synergism of five laws and the fuzzy comprehensive evaluation method. The analysis on synergy between large-scale coal mining and the eco-environment protection in Shendong is also conducted,arriving at the conclusion that synergetics of Shendong 's eco-environment protection is"good". And thus,the result sheds light on the fact that while working to quench China's energy demand on its path towards a modernized large coal mine complex,Shendong,as part of Shenhua Group's mining operation,has applied innovative management concepts and models to improve eco-environment for harmony and win-win results between resource exploration and environmental protection.

Study on the change rule of groundwater level and its impacts on vegetation at arid mining area

The shallow groundwater in Shendong mining area was broken because of large-scale underground mining activities. Selecting 32201 working-face as research area, analyzed the change rule of groundwater level and aquifer thickness under mining impact with a large number of water level observation data. Then, the impacts of groundwater level change on vegetation were analyzed by the relationship theory of arid area groundwater and vegetation. The results show that the aquifer structure and the water condition of supply flow and drainage are changed by the water proof mining. The groundwater level recovere only a little compared with the original groundwater level in two years. But the great change of groundwater level do not have notable influences on vegetation of this mining area, and further study indicates that there are certain conditions where groundwater level change impacted on vegetation. When the influence of groundwater level change was evaluated, the plant ecological water level, warning water level and spatial distribution character of original groundwater and mining-impacted groundwater-level change should be integrated.

Status quo and prospect of the development for underground coal mine refuge chamber

As one form of the energy resources, coal is becoming more and more important. Due to the particularity in coal mine production, mine accidents some time occur in countries all over the world, which result in large casualties and economic losses. As equipment that can provides the miners with an emergency shelter when the coal mine accidents occur, the under ground coal mine refuge chamber is paid more and more attention by coal mine enterprises, and the application of the refuge chamber is increasingly widespread. The general functions, the classification, and the successful applications of the underground coal mine refuge chamber are illustrated first, and the research significance on the tmderground coal mine refuge chamber is stated. Following, the development status quo at home and abroad for the refuge chamber is introduced. Then, the implementation methods for the key functions of the underground coal mine refuge chamber are demonstrated. Finally, the prospect for the development of the underground coal mine refuge chamber is stated.

Pyrolysis and co-pyrolysis of lignite and plastic

The study firstly discusses the pyrolysis characteristics and kinetics by thermogravimetric analysis （TGA）, and then investigates the pyrolysis of lignite and co-pyrolysis with plastic （polyethylene or polypropyl- ene） in tube furnace. Meanwhile, the research focuses on the co-pyrolysis products under different mix- ing ratios as well as pyrolysis products at different testing temperatures and heating rates. The results show that higher final testing temperature and lower heating rate contribute to bond fission in lignite pyrolysis, resulting in less char product. In co-pyrolysis, lignite acts as hydrogen donor, and the yields of char and water rise with increasing amount of plastic in the mixture, while the yields of gas and tar decrease; and a little admixture of plastic will promote the production of gas and tar. Kinetic studies indi- cate that in temperature range of 530-600℃, activation energies of lignite are higher than those of lig- nite/plastic blends, and as plastic mass ratio increases from 0% to 10%, samples need less energy to be decomposed during co-pyrolysis.

大准铁路快速相控阵钢轨探伤技术研究

随着大准铁路运量逐年增加,钢轨伤损数量增多,种类复杂化,危及铁路行车安全。目前大准铁路钢轨探伤主要采用手推式探伤仪,效率低,成本高。近年来国内各铁路企业逐渐引进国外大型钢轨探伤车,取得了一定的使用效果,但受对中不良等因素制约,核伤漏检率高,无法适应国内重载铁路钢轨探伤需求。本文基于国际先进的快速相控阵技术,提出一种相控阵超声波探头布局方式,在高速、高效检测前提下,可较好兼容不同轨型或不同打磨量钢轨,有效克服了对中不良等问题对检测的影响,提升了钢轨缺陷尤其是轨头核伤的检出率,节省了探伤成本。

Factors affecting the dynamic response of pre-stressed anchors after transient excitation

The wide application of pre-stressed bolting technology in coal mine tunnels has made the nondestructive stress wave reflection method of determining bolting quality an important one. The effect of the support plate on the dynamic response of the pre-stressed anchor is of particular interest. A theoretical analysis and numerical simulations are used to identify the factors affecting the contact stress between the support plate and the rock wall. A formula allowing the calculation of contact stress is presented. Stress wave propagation through the nut, support plate, and rock wall are predicted. The dynamic response signals were measured in the field using prestressed anchors pre-tightened to different torques. The effects from the support plate on the dynamic response were recorded and the results compared to the predictions of pre-stressed anchor. This work provides a theoretical reference for the signal processing of dynamic reflected wave signals in anchor bolts.

Practice and adaptable conditions classification of aquifer-protective mining in longwall coalface for shallow seam with thin bedrock

A set of adaptable conditions classification of aquifer-protective mining in the Iongwall coalface for shallow coal seams with thin bedrock was put forward to deal with the conflict between water protection and high efficiency for the mining field in west China. This classification was suitable for shallow coal seams with different thickness and was beneficial to the local environmental protection. Using the 3-Universal Distinct Element Code （3DEC） numerical software, the height of the fractured zones for shallow coal seams with thin bedrock was calculated and analyzed, and its predicting formula was achieved. Meanwhile, according to the lithology and the weathering degree of the shallow coal seam the thickness of the protective layer was determined as 10 m and the overlying water body of loose water-bearing sand for shallow coal seams with thin bedrock was divided into three types, namely, weak, medium and strong. Based on these, the necessary bedrock thickness of the Iongwall coalface for shallow coal seams with thin bedrock was confined according to the different mining height and water yield nature of the overlying loose water-bearing sand. Combined with the present mining status, a set of new methods of adaptable conditions classification of aquifer-protective mining technology in the Iongwall coalface for shallow coal seams with thin bedrock was put forward.

Clean Energy： Opportunities and Challenges

Human existence depends on energy, which is our basic material safeguard. Energy is imperative for economic and social development, and energy technology is an important conduit through which energy is harnessed and utilized, thereby promoting social development and progress.

浅谈新建火电厂选用AP系列风机的系统配置和性能要求

AP系列风机即动叶可调轴流式风机,现阶段在火电厂的运用最为普遍。根据不同的用途可分为一次风机、二次风机、引风机等。锅炉引风机由于长期在烟气温度高、烟气含尘量高并且烟气存在酸露腐蚀的恶劣条件下运行,因此要求新建机组选用的AP系列风机具有合理的系统配置和良好的性能。论文以神华国能集团有限公司重庆发电厂迁建项目2×660MW超超临界机组为例,根据AP系列风机的工作原理,探讨了选用AP系列风机的系统配置和性能要求。

Synergetic Management Theory for Coal-Based Energy Engineering and the Engineering Practice of Shenhua

To deal with problems in synergetic development of coal-based energy engineering,this paper,guided by the philosophy of engineering,proposes the synergetic management philosophy of "factors coordination,systems synergy,dynamic optimization and three-dimension planning." The paper also establishes the synergetic management system characterized by systems factor synergy,resource-environment synergy and systems boundary extension and supported by the "two-wheel driven"management innovation and technological innovation.In addition,the paper presents a multi-objective dynamic optimization model for energy engineering,designed based on Shenhua's own engineering practice,to analyze Pareto optimal solution in three scenarios:best resource allocation,minimal environmental impact and maximal value creation.This provides important reference to synergetic development strategies and decision-making in engineering management.

Development of a supercritical and an ultra-supercritical circulating fluidized bed boiler

The supercritical circulating fluidized bed(CFB)boiler,which combines the advantages of CFB combustion with low cost emission control and supercritical steam cycle with high efficiency of coal energy,is believed to be the future of CFB combustion technology.It is also of greatest importance for low rank coal utilization in China.Different from the supercritical pulverized coal boiler that has been developed more than 50 years,the supercritical CFB boiler is still a new one which requires further investigation.Without any precedentor engineering reference,Chinese researchers have con ducted fundamental research,development,design of the supercritical CFB boilers independently.The design theory and key technology for supercritical CFB boiler were proposed.Key components and novel structures were invented.The first 600 MWe supercritical CFB boiler and its auxiliaries were successfully developed and demonstrated in Baima Power Plant,Shenhua Group as well as the simulator,control technology,installation technology,commissioning technology,system integration and operation technology.Compared with the 460 MWe supercritical CFB in Poland,developed in the same period and the only other supercritical one of commercial running in the word beside Baima,the 600 MWe one in Baima has a better performance.Besides,supercritical CFB boilers of 350 MWe have been developed and widely commercialized in China.In this paper,the updated progress of 660 MWe ultra-supercritical CFB boilers under development is introduced.

Characteristics of atmospheric volatile organic compounds in urban area of Beijing: Variations, photochemical reactivity and source apportionment

Atmospheric volatile organic compounds(VOCs)were observed by an on-line gas chromatography-flame ionization detector monitoring system from November 2016 to August 2017 in Beijing.The average concentrations were winter(40.27±25.25μg/m3)>autumn(34.25±19.90μg/m3)>summer(32.53±17.39μg/m3)>spring(24.72±17.22μg/m3).Although benzene(15.70%),propane(11.02%),ethane(9.32%)and n-butane(6.77%)were the most abundant species,ethylene(14.07%)and propene(11.20%)were the key reactive species to ozone formation potential(OFP),and benzene,toluene,ethylbenzene,mxylene+p-xylene and o-xylene(54.13%)were the most reactive species to secondary organic aerosol formation potential(SOAFP).The diurnal and seasonal variations indicated that diesel vehicle emission during early morning,gasoline vehicle emission at the traffic rush hours and coal burning during the heating period might be important sources.Five major sources were further identified by positive matrix factorization(PMF).The vehicle exhaust(gasoline exhaust and diesel exhaust)was found to be contributed most to atmospheric VOCs,with 43.59%,41.91%,50.45%and 43.91%,respectively in spring,summer,autumn and winter;while solvent usage contributed least,with 11.10%,7.13%,14.00%and 19.87%,respectively.Biogenic emission sources(13.11%)were only identified in summer.However,both vehicle exhaust and solvent usage were identified to be the key sources considering contributions to the OFP and SOAFP.Besides,the contributions of combustion during heating period and gasoline evaporation source during warm seasons to OFP and SOAFP should not be overlooked.

Progress of circulating fluidized bed combustion technology in China:a review

Circulating fluidized bed(CFB)technology plays an important role in the utilization of low-grade coal in China.This article reviews CFB combustion technology development in China and summarizes recent achievements.Since 1990 Chinese engineers and researchers have been undertaking work to improve CFB boiler technology.A completely novel CFB boiler design theory was developed and used in the domestic manufacturing of CFB boilers with various capacities.China is the largest supplier and customer of CFB boilers in the world due to the widespread use of CFB boilers.In 2007,the lower energy consumption CFB technology was successfully developed by re-specifying the fluidization state,which reduced the power consumption of forced fans and solved the potential erosion problems on the water wall.Afterwards,in order to increase the electric power generation efficiency,the supercritical CFB(SCCFB)boiler was developed and the first 600 MW SCCFB boiler was demonstrated and put into commercial operation in 2013.The success of the technology is evident with over 80 SCCFB boilers on order with capacities of 350 MW to 660 MW.Chinese scientists and engineers are also developing technology to lower the emissions of CFB combustion to meet the requirements of China’s strict emission regulations.This emission reduction is through high-efficiency desulfurization by limestone injection into the furnace and low NOx combustion,ultra-low emission of SO2 and NOx in the furnace can be realized by improving the bed quality and increasing the solid circulation rate.There is currently further research and design development being undertaken to develop a 660 MW ultra-supercritical CFB(USCCFB)boiler.The new boiler is expected to be operational before 2020 resulting in higher efficiency and lower energy consumption and emissions.

Crystalline mesoporous transition metal oxides： hard-templating synthesis and application in environmental catalysis

Mesoporous silicas such as MCM-41 and SBA-15 possess high surface areas, ordered nanopores, and excellent thermal stability, and have been often used as catalyst supports. Although mesoporous metal oxides have lower surface areas compared to mesoporous silicas, they generally have more diversified functionalities. Mesopor- ous metal oxides can be synthesized via a soft-templating or hard-templating approach, and these materials have recently found some applications in environmental cata- lysis, such as CO oxidation, N20 decomposition, and elimination of organic pollutants. In this review, we summarize the synthesis of mesoporous transition metal oxides using mesoporous silicas as hard templates, high- light the application of these materials in environmental catalysis, and furnish some prospects for future develop- ment.