Preparation, characterization and salt-resistance of a coal based super absorbent composite

Potassium humate was extracted from brown coal. A novel super absorbent composite, poly （acrylic acid-co-acryla- mide）/potassium humate （PAA-AM/KHA）, was prepared by graft polymerization of acrylic acid, acrylamide and coal based potassium humate using N, N＇-methylenebisacrylamide as a crosslinker and potassium peroxydisulfate as an initiator. The effects of reaction temperature, degree of neutralization of the poly （acrylic acid） and the amounts of crosslinker, initiator and potassium humate were investigated. Salt resistance tests were also carded out. The composite prepared under optimal conditions had a potassium bumate content of 10% and exhibited a water absorption of 770 g/g in distilled water, and 349, 286 and 41 gig in 0.5 mol/L KC1, MgC12 and A1CI3 solutions respectively. The results indicate that the salt resistance of PAA-AM/KHA was superior to that of poly （acrylic acid-co-acrylamide） because of the collaborative effect of functional groups of the coal based potassium humate. The PAA-AM/KHA micro powder was characterized by IR spectroscopy and the micrographic surface was characterized by scanning electron microscopy. Introduction of potassium humate into the poly （acrylic acid-co-acrylamide） structure creates a composite more suitable for use as a water-managing material in the renewal of arid and desert environments. The salt resisting property of the composite is improved, production costs are reduced and the growth stimulant effect is still present.

Coal Tar Derived Metallocene Catalyst for Polymerization of 1-Decene into Low-viscosity Poly-α-Olefin Lubricating Base Oil

The production of poly-α-olefins(PAOs)has attracted attention due to their excellent viscosity-temperature dependence,wear characteristics,oxidative properties,and high thermal stability.In this study,indene extracted during coal tar refining was used as a raw material to synthesize a bis(indenyl)zirconium dichloride metallocene catalyst.A PAO with low viscosity and a high viscosity index was produced via the oligomerization of 1-decene in the presence of both the prepared metallocene and a methylaluminoxane(MAO)co-catalyst.Notably,the effects of different synthesis reaction parameters,such as Al:Zr ratio,amount of catalyst,and reaction temperature,on the conversion ratio and product selectivity were investigated in detail.The produced PAO was thoroughly characterized using Fourier-transform infrared,^(13)C,and^(1)H nuclear magnetic resonance spectroscopies;gas chromatography;and viscosity measurements.At 70℃,the metallocene catalyst created more stable active sites.In addition,the alkylation effect of MAO was noticeable.Interestingly,the obtained catalysis results demonstrated that a high conversion ratio of~93%was achieved at a low reaction temperature of 70℃,with a catalyst dosage of 0.0848 mmol and Al:Zr ratio of 8.48mmol:0.0848mmol.Moreover,under these optimal conditions,the kinematic viscosity of PAO was 4.25 mm2/s at 100℃,and the viscosity index was 139,indicating good viscosity-temperature properties.

Effects of Surface-activated Coal Gangue Aggregates on Properties of Cement-based Materials

Effects of calcined coal gangue （CG） aggregates treated by the surface thermal activation on the flowability and strength, and paste-CG aggregate interfaces of the cement-based material were investigated. The experimental results show that the compressive and flexural strength of the cement-based material with the calcined CG aggregates is much higher than that of the material with the natural CG aggregates, but the flowability of the material with calcined CG is significantly reduced with the calcined time. The strength of the material with the calcined CG aggregates only increases little with the calcined time at the same w/c ratio, but is reduced with the calcined time at the same flowability. The CG aggregates calcined by the surface thermal activation obviously overcomes the disadvantages of fully calcined CG.

In Situ Synthesis of NaY Zeolite with Coal-Based Kaolin

NaY zeolites were in-situ synthesized from coal-based kaolin via thehydrothermal method. The effects of various factors on the structure of the samples were extensivelyinvestigated. The samples were characterized by N_2 adsorption, XRD, IR and DTG-DTA methods, andthe results show that the crystallization temperature and amount of added water play an importantrole in the formation of the zeolite structure. The 4A and P zeolites are the competitive phasepresent in the resulting product. However, NaY zeolites with a higher relative crystallinity,excluding impure crystals and the well hydrothermal stability, can be synthesized from coal-basedkaolin. These zeolites possess a larger surface area and a narrow pore size distribution, and thismeans that optimization of this process might result in a commercial route to synthesize NaYzeolites from coal-based kaolin.

Migration behaviors and kinetics of phosphorus during coal-based reduction of high-phosphorus oolitic iron ore

To understand the migration mechanisms of phosphorus(P)during coal-based reduction,a high-phosphorus oolitic iron ore was reduced by coal under various experimental conditions.The migration characteristics and kinetics of P were investigated by a field-emission electron probe microanalyzer(FE-EPMA)and using the basic principle of solid phase mass transfer,respectively.Experimental results showed that the P transferred from the slag to the metallic phase during reduction,and the migration process could be divided into three stages:phosphorus diffusing from the slag to the metallic interface,the formation of Fe P compounds at the slag metal interface and P diffusing from the slag metal interface to the metallic interior.The reduction time and temperature significantly influenced the phosphorus content of the metallic and slag phases.The P content of the metallic phase increased with increasing reduction time and temperature,while that of the slag phase gradually decreased.The P diffusion constant and activation energy were determined and a migration kinetics model of P in coal-based reduction was proposed.P diffusion in the metallic phase was the controlling step of the P migration.

Experimental Study on Chemical Looping With Oxygen Uncoupling Using Copper Based Oxygen Carrier and Different Volatiles Contained Coal Chars

采用溶胶一凝胶法制备CuO／CuAl204氧载体，研究了该氧载体在N2气氛下的释氧性能，发现氧载体774℃时开始释氧，且随着温度的升高氧气含量不断升高。随后，在流化床反应器中研究了挥发分含量不同的6种煤焦的化学链氧解耦燃烧（chemicalloopingwithoxygenuncoupling，CLOU）特性，结果表明，挥发分含量的增加和温度的升高均会加速煤焦燃烧，煤焦中碳元素转化率达到95％所需要的时间随着挥发分含量及温度的升高不断减少，相应的碳的平均转化率也不断增加；然而，较高的挥发分含量和反应温度都会导致CO2捕集率的下降。对于挥发分含量低的高平煤焦和东欢坨煤焦，C02捕集率超过99％，而对于挥发分高的胜利褐煤焦，C02捕集率不足95％。

Making Ferronickel from Laterite Nickel Ore by Coal-Based Self-Reduction and High Temperature Melting Process

Based on the process of coal-based self-reduction and melting separation at high temperature, it was investigated that the effect of process factors on the reduction of iron and nickel oxide, the metal yield and the nickel content in ferronickel about the laterite nickel ore, was from Philippines and contented low nickel, high iron and aluminum. The results showed that if the C/O mole ratio was not higher than 0.5 and the reduction temperature was kept as 1200°C and then increased up to 1500°C, the metal could not separate from molten slag for the A series of experiments, which were only added CaF2. However, when the C/O ratio was added up to 0.6 - 0.8, the metal could separate well from the slag, and the yields of Fe and Ni increased gradually. But the nickel content in the metal declined from 1.79% to 1.34%. When the C/O ratio increased to 1.2, and the temperature of melting products obtained at 1200°C and rose to 1550°C, the separation of metal from slag could not be realized in B group of tests, which were only added hydrated lime. However, when both of CaF2 and hydrated lime were added, the metal could separate from slag in C group. In order to increase the content of nickel in the metal, it is necessary to restrain the reduction of iron oxide. When the C/O mole ratio is 0.6, the nickel content of metal could be 1.79%, which was higher than the theoretical ratio 1.65% of Ni/(Ni + Fe) of the latcritic nickel ore, but the yield of nickle was only 71.3%.

Conjunctive Utilization of Water Resources at the Yulin Coal-Mine Base in China

Shortages in water resources and the fragile ecosystem by coal-mine water affect the Yulin coal-mine base in northwest China, so taking coal-mine water into account is an important issue for the sustainable management of water resources. This paper aims to explore how the Yulin coal-mine base can improve its conjunctive utilization of water resources. Integrated utilization is proposed by establishing a multi-objective, multi-water-source, optimal-allocation model;setting up an integrated information platform;and giving very useful measures and policy suggestions to the local government. Finally, this research can also serve as an example of integrated water utilization for other energy bases.

Cs/CoAl-LDO@X催化剂制备及甲苯侧链烷基化反应性能研究

以X分子筛为载体,在其表面生长CoAl-LDH层状氢氧化物,浸渍Cs后焙烧,制备得到一系列不同CoAl-LDO含量的Cs/CoAl-LDO@X催化剂。利用XRD、SEM、TPD表征催化剂的结构、形貌及酸碱性质,在固定床微反应器上评价催化剂的甲苯侧链甲醇烷基化一步制苯乙烯的反应性能,研究不同CoAl-LDO含量对催化性能的影响。结果表明,随着CoAl-LDO含量的增加,催化剂的酸、碱活性中心的量有一定的增加;不同CoAl-LDO含量的催化剂对甲苯侧链烷基化反应都具有良好的催化性能。在最优反应条件下,甲苯转化率2.55%,苯乙烯选择性41.61%,苯乙烯和乙苯的总选择性可达92.51%。

Feasibility Ananlysis of Building Pithead Power Plants in North Shaanxi and Ningxia Coal Bases

North Shaanxi and Ningxia are extremely abundant in coal resources, with excellent geographical positions and transport facilities, suitable to build large size pithead power plants. This paper details the coal resources in North Shaanxi Province and Ningxia Autonomous Region, fuel coal and transportation conditions for building large size pithead power plants, and carries out the analyses of economic benefits and electricity prices of bidding for access to grid for the six recommended power plants. The analyses show that these power plants, after built up, will have strong competitive powers and make contributions for the sustainable development of power industry in North China and Shandong Province.

煤电化基地大宗固废“三化”协同利用基础与技术

我国14个大型煤炭基地及89个大宗固体废弃物综合利用示范基地建设,标志着矿区大宗固废利用已被纳入全国战略发展布局。长期以来煤炭资源高强度的开发与利用,造成矿区浅埋煤层资源临近枯竭,煤电化基地大规模固废堆积及地表沉陷,已成为制约矿区绿色低碳、高质量发展的难题。大宗煤基固废协同利用与绿色充填是解放“三下一上”压煤,延长矿井服务年限,实现固废无害化、资源化、规模化“三化”利用的有效途径。基于产煤大省山西省、“华东能源粮仓”安徽两淮基地及宁东能源化工基地的煤基固废种类和产量,详细阐述了以煤矸石、粉煤灰、炉底渣、气化渣和脱硫石膏等为主要材料的煤基固废通过重金属吸附解吸和络合钝化技术实现无害化处置,列举煤基固废分类应用于低热值煤基固废发电、制备建筑材料如水泥、砖瓦等资源化利用途径,对比分析煤基固废采煤沉陷区复垦回填及井下充填规模化利用途径,突出煤基固废井下充填的优越性。基于煤电化基地深部煤炭资源,提出绿色充填开采理论与关键技术,包括深部煤矸石源头减量与采选充协同技术、充填材料高效制备与深部井下输送技术及煤基固废充填材料深部多场耦合机理,探究多源煤基固废从源头、过程到终端的深部充填开采全过程的技术原理与方法,以解决矿区深部井下充填的技术难题。根据宁东基地任家庄煤矿、山西省霍尔辛赫煤矿及淮北矿区地质条件和充填目的,分别提出超前钻孔注充低位充填方案、关键层非典型特征条件下多离层梯级注浆方案和煤基固废协同利用关键技术,综合矿山固废处置与利用、深部煤炭资源开发利用、地表沉陷控制、生态环境保护等优势,形成煤电化基地大宗固废协同利用与绿色开采模式,为煤炭开采高质量化和环境低损伤化提供参考。

玻璃纤维改性煤基固废胶结充填材料性能研究

基于煤矸石、粉煤灰等煤基固废再生资源利用和胶结充填材料性能优化问题,研究了玻璃纤维掺量、长度和养护龄期对煤基固废胶结材料输送性能和力学性能的影响规律,探讨了玻璃纤维增强机理。实验结果表明:玻璃纤维改性煤基固废胶结材料坍落度随纤维长度和掺量的增大而减小,但均大于200 mm,满足输送性能要求;抗压强度和抗拉强度随纤维长度的增大呈先增高后降低,随纤维掺量的增加而增高的变化规律;当玻璃纤维长度为6 mm、掺量为0.3%时,质量分数为79%的煤基固废胶结材料的综合性能最佳;玻璃纤维改性煤基固废胶结材料水化反应后,生成的针状和团状产物填充了材料细小裂隙且附着于纤维表面,能够有效提高材料的力学性能。

不定型煤基活性焦制备及预处理影响研究

我国煤炭燃烧排放大量的SO2和NOx等导致了严重的空气污染,需要寻找一种清洁高效的烟气联合脱硫脱硝技术.煤基活性焦因其脱除效率高,再生能力强等诸多优点备受关注,但目前的研究主要集中在柱状和粉末状活性焦上.为研究大粒径煤基活性焦的制备参数和预处理对活性焦理化特性的影响,对原煤颗粒进行高温空气预氧化处理,并通过炭化-水蒸气活化两步法制备活性焦.结果表明:低温长时间活化可使炭化料内部孔隙充分刻蚀,显著提高比表面积和孔容,以水蒸气作为活化剂有利于微孔和介孔协同发展,适合制备大粒径分级孔结构活性焦.700℃活化3 h制得的府谷煤活性焦比表面积为429.54 m^(2)/g,介孔占比27.80%;850℃活化3 h制得的大同煤活性焦比表面积为892.20 m^(2)/g,介孔占比21.46%.高温空气预氧化能够改变原煤内部结构,对府谷煤颗粒在200℃下预氧化15 h后,氧化煤内部成分和结构基本稳定,脂肪结构被消耗的同时生成了大量含氧官能团.预氧化处理对炭化过程的影响较为显著,氧化煤在炭化过程中热塑性特征显著降低,减少了焦油对孔隙的堵塞,此外,含氧官能团的交联作用也促进了煤中大分子的缩聚和孔隙的形成,从此促进初步孔隙的发展.虽然预氧化使得活性焦的比表面积和孔容都有所增大,但活化剂和样品之间的成孔路径未产生改变.

煤基压块活性炭的制备及吸附水溶液中Cr(Ⅵ)的能力研究

为了降低压块活性炭的制备成本,以大同不黏煤为主料,桃山焦煤和重相沥青为黏结成分,以高温煤焦油和水为成型助剂制备压块活性炭。依靠调节配煤比例和改变活化条件来调控活性炭孔结构。利用碘吸附值、亚甲蓝吸附值、耐磨强度等表征活性炭常规性能;研究了样品吸附水溶液中Cr(Ⅵ)的能力,并考察了活性炭再生效率和质量损耗情况。结果表明:在大同不黏煤、桃山焦煤、重相沥青、高温煤焦油和水的配比为51∶24∶9∶7∶9的基础上,活化温度和时间分别为875℃和2.5 h的条件下制备出的压块活性炭性能最优,其耐磨强度为90%,碘吸附值为902 mg/g,亚甲基蓝吸附值为270 mg/g,比表面积为992.6 m^(2)/g;对水溶液中Cr(Ⅵ)最大吸附容量可达27.3 mg/g;质量分数为5%的硝酸溶液对饱和活性炭在50℃条件下再生8 h效果最佳,再生5次以后,其质量损耗率为21%,性能恢复率为70.06%。

气体水合物合成研究进展

水合物法捕集与封存CO_(2)气体可服务于大规模减排的技术需求,加速“碳中和”目标的实现,对应对气候变化具有重要意义。从气体水合物的基本性质、生成机理及模型,多孔介质中水合物合成,水合物合成的分子动力学模拟等方面,综述了前人针对水合物合成领域的研究现状,提出了气体水合物合成过程中存在的科学问题,并对气体水合物的发展及煤系地层CO_(2)水合物的封存方向进行了评价。研究认为,CO_(2)气体的溶解度是限制准确计算多孔介质中水合物储气量的关键因素;气体水合物的局部结构化(成核)机制复杂,仍需深入研究;高纬度及永久冻土区煤系地层可作为水合物法封存CO_(2)气体的地下空间。

黄河流域煤炭-煤电-煤化工场地特征精准智能识别方法及应用

黄河流域是“能源流域”,兼具生态环境治理和经济社会发展的重任,涉煤产业场地类型、数量及特征的精准智能识别是流域能源资源-低碳发展-生态保护的关键基础问题。研究融合多源数据与深度学习算法,从流域-基地-场地尺度对黄河流域13个大型煤电基地的煤基场地特征精准解析,获得煤电基地高精度、高质量的本底信息,提出一种实时实景智能识别涉煤产业空间特征的新方法。(1)筛选Google image、GF-6影像、Sentinel-2影像等多源数据,采集13个大型煤电基地煤基场地样本,构建煤炭场地(露天)、煤炭场地(井工)、煤电场地、煤化工场地4类数据集,涵盖21种样本类型。按照每种样本六面体设定6×10个样本,共计1 260个场地样本,分析得出最适样本数量-最高识别效率-最优识别模型的置信区间为80%~86%。(2)建立了煤基场地类型量化模型(Coal-based Site Classification Quantitative Model, CSCQM)和煤基场地范围特征模型(Coalbased Site Range Characteristic Model, CSRCM),模型平均精准度为0.837。明析了黄河流域涉煤产业场地本底信息,提出Google image底图叠加场地智能识别模型解算结果的高精度场地智能识别方法。(3)解析了流域神东煤炭-煤电产业集聚区精准本底数据,依据遥感生态指数(Remote Sensing Based Ecological Index,IRSE)分析,煤基场地分布2 km核心区地表生态质量受煤炭、煤电产业影响明显,5 km缓冲区则影响不明显,而8 km控制区基本不受煤炭、煤电产业影响,从而给出了“动态修复”与分区域、分阶段重点治理等低碳路径。(4)解析了流域宁东煤炭-煤电-煤化工产业集聚区精准本底数据,2022年煤炭场地17.81 km^(2)、占比34.1%,煤化工场地22.3 km^(2)、占比42.6%,煤电场地12.2 km^(2)、占比23.3%,煤化工场地>煤炭场地>煤电场地。进而采用PSR(Pressure-State-Response)模型得到风险管控综合得分53.93分,较2003年提高了27.2%。划分生态维护区、生产监测预警区、损毁修复重建区、其他调控区的分区管控模式。研究为涉煤产业煤基场地潜在污染控制、场地治理及区域生态修复提供技术方法与实践支撑。

大宗煤基固废膏体充填材料少水化配比优化研究

为解决西部采煤区固废多、处理难的问题,以宁东矿区的脱硫石膏、粉煤灰、水泥为主要原料,对原料的微观形态及少水配比的煤基固废膏体充填材料的成分进行分析,以初期流动性、脱模后7 d和28 d的抗压强度为指标进行充填材料配比优化。设计了3因素3水平17组配比方案,建立响应面回归模型,分析单因素及多因素交互作用对少水充填材料强度和流动性的影响。研究结果表明,粉煤灰与水泥质量比是影响少水充填材料强度的重要因素,料浆质量分数是影响少水充填材料流动性的重要因素。少水配比的煤基固废膏体充填材料的最优配合比:脱硫石膏质量分数53%,粉煤灰与水泥质量比2∶1,料浆质量分数74%。波速与强度的响应关系表明,可以利用充填体的波速来预测其强度。

煤的结构基因与煤基碳材料构建研究进展

“双碳”目标的实现必将带来煤炭作为燃料用量的迅速减少,寻找煤炭的高附加值利用途径是煤炭行业可持续发展的迫切需求。简要介绍了基于单原子组装的无烟煤催化石墨化研究和焦炭催化石墨化研究,以及碳化硅炉炉芯石墨产品和特征,其晶体片径可达100um及以上,且受煤及煤基中间体结构的影响较少。重点介绍了无烟煤、烟煤、褐煤的结构特征与碳材料构建,研究发现煤的结构基因对煤基碳材料的构建有着决定性影响。无烟煤高固定碳含量的稳固碳结构有利于形成高强度的多孔炭和增碳补强剂等碳材料,无烟煤基高温石墨片径在几微米左右,片层平行度较差、交叉较多,适用于制备大规格炭电极的多晶石墨电极、电解槽、化学惰性通道。以烟煤为原料的煤沥青和焦炭中的炭青质是构成褶皱石墨的良好前驱体,煤沥青经针状焦石墨化因包含晶体液相生长过程,晶体片径尺寸可达数十微米以上,所形成的褶皱石墨经球团和浸渍包覆可以作为锂离子电池良好的负极储锂材料;焦炭中非晶态的固定碳也是制备硬碳材料的良好原料。褐煤稀疏的大分子架构和多孔颗粒形态有利于浸渍类碳材料的构建,是制备催化剂载体的优质原料。

保供降碳目标下能源转型模式及转型时点分析

应对气候变化目标要求全球能源系统进行广泛而深刻的转型。由于资源禀赋、能源战略、技术水平等差异,各国能源转型进程呈现出明显的异质性特征。通过对主要国家能源转型特征与减煤路径的分析,归纳了4种典型模式:能效提高模式、增气减煤模式、煤炭洁净利用模式、新能源替代模式,不同模式在不同时间点上与经济社会发展交互影响形成了国际能源转型的内在驱动机制。采用面板数据模型识别了影响能源转型模式的重要因素,并利用历史趋势分析方法对我国化石能源消费“拐点”与减煤时间节点进行研究。研究表明,当人均GDP达到25500美元时,发达国家即出现化石能源减少拐点。国家创新指数和城镇化与煤炭消费占比呈负相关,第二产业增加值占比与煤炭消费占比呈正相关。我国预计减煤时间范围在2028-2035年,化石能源消费减少时点在2040年左右。考虑到我国以煤炭为主的能源资源禀赋,我国能源转型目标的实现须依赖于煤炭洁净利用为主的转型路径,大力发展低碳化现代煤基能源体系,改变传统煤炭利用理念与方式,为未来多能耦合的新型能源体系提供重要支撑。