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含泥金矿石高效选别流程研究与生产实践

中国矿业 2024年第10期33卷 234-239页

作者：白俊智刘显华李欢刘泽洪紫金矿业集团股份有限公司福建上杭364200 文山麻栗坡紫金钨业集团有限公司云南麻栗坡663600

某金矿选矿厂处理蚀变岩型低硫化物含碲金矿石,该矿石原生矿泥含量高达15%,且矿泥中金有富集现象,采用常规三段破碎+洗矿+两段闭路磨矿+充气式浮选机单一浮选的工艺流程进行选别,存在流程复杂、劳动生产率低、生产组织不顺畅、浮选作业... 详细信息

某金矿选矿厂处理蚀变岩型低硫化物含碲金矿石,该矿石原生矿泥含量高达15%,且矿泥中金有富集现象,采用常规三段破碎+洗矿+两段闭路磨矿+充气式浮选机单一浮选的工艺流程进行选别,存在流程复杂、劳动生产率低、生产组织不顺畅、浮选作业波动较大、尾矿中细粒级金属流失较多、回收率偏低等问题。扩产技改时,采用粗碎+半自磨+球磨的SAB流程取代原碎磨流程,采用浮选柱粗精选、浮选机扫选的柱-机顺序浮选流程取代原单一浮选机浮选流程,后创造性的将柱-机顺序浮选流程改进为浮选柱粗精选、浮选机精扫选的柱-机双精选流程,并对调浆设备进行高效化改造,解决了原工艺流程存在的诸多弊端。劳动生产率提高了25%,吨矿成本降低了20%,金回收率提高了2.44个百分点,年创效益1568.1万元,经济效益和社会效益显著。该高效选别流程的成功实践,对同类型矿石的高效回收具备较强的借鉴意义。

关键词：高含泥金矿石碎磨浮选柱-机联合流程高效调浆

Control Strategy Optimization of Voltage Source Converter Connected to Various Types of AC Systems

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 77-84页

作者： zehong liu Senior Member Xianshan Guo State Grid Corporation of China Beijing 100031China

Connecting the voltage source converters(VSCs) to various types of AC systems results in different operation characteristics and core problems associated with traditional control strategies. Therefore, it is necessary to optimize the control strategies of the VSCs according to the types of AC *** the VSCs connected to islanded renewable power plants, a voltage/frequency(V/f) droop control strategy is proposed to damp fluctuations of AC voltage and frequency in the island,which is vital for bipolar VSC control. In addition, a multibranch impedance equivalent method for renewable power plants is proposed, with which large-scale renewable power plants can be modeled accurately in the frequency domain to prevent wide-band oscillation. For the VSCs connected to strong AC systems, smart AC voltage and coordinated frequency transient control strategies are proposed, which can improve AC system transient stability. For the VSCs connected to weak AC systems, the relationship between the system stability and strength is analyzed, and then the control strategy of inner-loop control parameter optimization and outer-loop power limiting(if necessary) is proposed to improve the stability of the allied system. The proposed strategies are verified by both software simulation and field commissioning.

关键词： Control strategy optimization islanded renewable power plants stability voltage source converter(VSC) AC system

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电-氢-碳耦合促进新能源基地开发模式研究

全球能源互联网 2024年第5期7卷 473-491页

作者：刘泽洪孟婧张瑾轩周原冰李隽全球能源互联网发展合作组织北京市西城区100031

实现全球“碳中和”,核心是推动能源绿色低碳转型,重要举措是推动新能源大规模基地化开发和高效消纳。针对偏远、水电不足地区新能源基地开发面临的低碳调节手段不足、电网配置和消纳能力有限、“风光火”开发模式降碳难等问题与挑战,... 详细信息

实现全球“碳中和”,核心是推动能源绿色低碳转型,重要举措是推动新能源大规模基地化开发和高效消纳。针对偏远、水电不足地区新能源基地开发面临的低碳调节手段不足、电网配置和消纳能力有限、“风光火”开发模式降碳难等问题与挑战,提出了基于电-氢-碳协同的新能源基地发展思路和开发模式,将氢基产业发展与新能源开发消纳、煤电灵活低碳转型深度融合,同时结合绿氢、绿氨、绿色甲醇等氢基产品制取工艺的技术发展和调节能力提升,量化分析绿电与绿色氢/氨/甲醇在终端消费市场的竞争力及经济效益,研判不同时期新能源基地开发与氢基产业协同发展的适用模式及应用时序,展望新能源基地电-氢-碳协同开发模式在中国三北地区以及北非等海外地区的应用前景。

关键词：新能源基地化开发沙戈荒电-氢-碳协同灵活调节资源绿色氢基产业

Sample Numbers and Optimal Lagrange Interpolation of Sobolev Spaces W_(1)^(r)

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Chinese Annals of Mathematics,Series B 2021年第4期42卷 519-528页

作者： Guiqiao XU zehong liu Hui WANG Department of Mathematics Tianjin Normal UniversityTianjin 300387China

This paper investigates the optimal recovery of Sobolev spaces W_(1)^(r)[-1,1],r∈N in the space L_(1)[-1,1].They obtain the values of the sampling numbers of W_(1)^(r)[-1,1]in L_(1)[-1,1]and show that the Lagrange interpolation algorithms based on the extreme points of Chebyshev polynomials are optimal ***,they prove that the extreme points of Chebyshev polynomials are optimal Lagrange interpolation nodes.

关键词： Worst case setting Sampling number Optimal Lagrange interpolation nodes Sobolev space

Fractal model of lightning channel for simulating lightning strikes to transmission lines

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Science China(Technological Sciences) 2009年第11期52卷 3135-3141页

作者： HE JinLiang ZHANG XueWei DONG Lin ZENG Rong liu zehong Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Department of UHV Construction State Grid Corporation of ChinaBeijing 100031China

How to accurately evaluate the direct-strike lightning protection is one of the key issues in the design of transmission lines. In this paper, three important issues in applying the fractal simulation to the lightning protection of transmission lines were discussed, including the criteria and implementation of upward leader inception, the connection with the magnitude of lightning current, and the calculation and control of fractal dimensions. Then we conducted the simulation iterately, leading to statistical results, which indicate that even if the transmission line satisfies the perfect shielding condition, shielding failure fault remains possible. Furthermore, we calculated the shielding failure fault rates of an EHV line with different ground obliquities and distribution of strike points over the interval between two neighboring towers along a UHV-DC line to find out the weak point of transmission-line lightning protection. This work provides a promising approach for improving the lightning protection property of transmission lines by optimizing the configuration of shielding wires and phase or pole conductors.

关键词： lightning shielding failure transmission line fractal theory dielectric breakdown model electrogeometric model

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云南某白钨矿加温浮选尾矿再回收试验研究

中国钨业 2024年第2期39卷 46-52,69页

作者：刘泽洪白俊智刘显华李彬李欢文山麻栗坡紫金钨业集团有限公司云南文山663600 紫金矿业集团股份有限公司福建上杭364200

云南某白钨矿采用常温粗选、加温精选的浮选工艺,目前该白钨矿加温精选尾矿WO3品位达到0.27%,因此对该加温浮选尾矿进行浮选回收钨金属试验研究具有经济意义。由于该加温浮选尾矿矿浆浓度偏低为10.20%,且在加温浮选作业过程经水玻璃高... 详细信息

云南某白钨矿采用常温粗选、加温精选的浮选工艺,目前该白钨矿加温精选尾矿WO3品位达到0.27%,因此对该加温浮选尾矿进行浮选回收钨金属试验研究具有经济意义。由于该加温浮选尾矿矿浆浓度偏低为10.20%,且在加温浮选作业过程经水玻璃高温、长时间搅拌,白钨矿受到强烈抑制,再浮选回收率低,精矿品位难以得到提升。经过探索试验研究,将加温浮选尾矿矿浆浓度预先浓缩到40%,添加500 g/t水玻璃、400 g/t氧化石蜡皂进行粗选,可获得粗精矿WO3品位为1.741%,回收率为73.09%的粗选指标。选出的粗精矿经添加高效组合抑制剂(水玻璃15000 g/t+高效抑制剂BTF 15000 g/t)进行常温一粗三精的开路精选试验,可获得精矿WO3品位为11.65%、回收率为43.86%的精选指标。最终闭路试验流程为:加温浮选尾矿经过一次粗选二次扫选得到粗精矿后,经一次粗精选三次精选,可获得钨精矿WO3品位为10.52%、回收率为51.79%的选矿指标。

关键词：尾矿浮选矿浆预先浓缩常温精选高效组合抑制剂

Research on key technologies in±1100 kV ultra-high voltage DC transmission

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High Voltage 2018年第4期3卷 279-288页

作者： zehong liu Fuxuan Zhang Jun Yu Keli Gao Weimin Ma State Grid Corporation of China Xicheng DistrictBeijing 100031People's Republic of China DC Department State Grid Corporation of ChinaXicheng DistrictBeijing 100031People's Republic of China China Electric Power Research Institute Haidian DistrictBeijing 100192People's Republic of China State Grid Economic and Technological Research Institute Beijing 102209People's Republic of China

Based on completely mastering±800 kV transmission technologies,the first±1100 kV direct current(DC)transmission demonstration project is being constructed in *** theoretical analysis and a large number of experiments,the margin of switching overvoltage in converter stations,the configuration scheme and performance of lightning arresters,the shielding angles of ground lines under different geographical conditions,and the maximum air gap of lines have been *** switching impulse flashover characteristics of equipotential sphere and typical rod-plane air gaps are also *** external insulation is designed differently for light,medium,and heavy pollution *** the±1100 kV project,if the 8×1250 mm^(2)conductors are applied,the pole gap is 26 m and the height of the line is 25 m,all the electromagnetic parameters will meet the requirement of international electromagnetic *** key design points of±1100 kV converter transformers,smoothing reactors,converter valves,and wall bushings are researched and the 75 mH smoothing reactors,±1100 kV/5000 A converter valves,and±1100 kV/5523 A wall bushings are successfully *** optimised hierarchical connection modes and coordination control measure of the±1100 kV project are studied and the results can provide sufficient technical support for the demonstration project.

关键词： ±1100 smoothing insulation

组合药剂提升菱锌矿与白云石分选效果的机理研究

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金属矿山 2024年第9期 84-91页

作者：白俊智陈逸凡陈享享印万忠李欢刘泽洪紫金矿业集团股份有限公司福建龙岩364200 文山麻栗坡紫金钨业集团有限公司云南文山663600 中国冶金地质总局第二地质勘查院福建福州350108 福州大学紫金地质与矿业学院福建福州350108

易选硫化锌矿资源因大量开发而日趋枯竭,以菱锌矿为代表的氧化锌矿资源的高效开发利用愈发重要。菱锌矿与白云石同属碳酸盐类矿物,晶体结构相似,表面性质相近,浮选分离困难。通过浮选试验,系统研究了以油酸钠、十八胺、苯甲羟肟酸、水... 详细信息

易选硫化锌矿资源因大量开发而日趋枯竭,以菱锌矿为代表的氧化锌矿资源的高效开发利用愈发重要。菱锌矿与白云石同属碳酸盐类矿物,晶体结构相似,表面性质相近,浮选分离困难。通过浮选试验,系统研究了以油酸钠、十八胺、苯甲羟肟酸、水杨羟肟酸及其组合为捕收剂,四聚磷酸钠和氯化钙作为组合抑制剂条件下,菱锌矿与白云石的浮选特性。结果表明,单一捕收剂体系中,菱锌矿与白云石难以有效分选;水杨羟肟酸和油酸钠的捕收剂组合具有良好的协同效应,四聚磷酸钠与氯化钙的抑制剂组合具有较高的选择性,可实现菱锌矿与白云石的高效分选。采用晶体化学模拟计算、动电位分析、捕收剂吸附量分析等手段,对浮选结果与作用机理进行了阐释与验证。

关键词：菱锌矿白云石浮选组合药剂

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超高比例新能源弱电网系统供电关键问题研究

新型电力系统 2024年第3期2卷 282-296页

作者：刘泽洪周原冰李隽燕志宇郑炜全球能源互联网发展合作组织北京100031

随着电力系统中新能源并网规模快速增加,系统形态特征与运行机理发生深刻变化,特别对远离主网、缺乏传统能源的地区,面临电力保供和系统安全稳定等严峻挑战。现有研究多从源网荷储某一环节切入,提出中高比例新能源电力系统供电可靠性提... 详细信息

随着电力系统中新能源并网规模快速增加,系统形态特征与运行机理发生深刻变化,特别对远离主网、缺乏传统能源的地区,面临电力保供和系统安全稳定等严峻挑战。现有研究多从源网荷储某一环节切入,提出中高比例新能源电力系统供电可靠性提升方法,缺乏对超高比例新能源弱电网系统特有难题的针对性考虑及系统性、前瞻性解决方案。为此,文中以新能源电量占比超过80%、新能源并网点短路比低于1.5的弱电网系统为研究对象,提出含电源及灵活调节资源优化配置、电网组网模式、暂态稳定运行分析的总体研究框架,并以我国西部某超高比例新能源弱电网系统为例开展实证研究。研究成果表明,所提方案以超高比例新能源发电为基础,以弱联电网为载体,以多元储能及负荷柔性调节为灵活性支撑,以构网控制技术为安全支撑,能有效保障系统可靠供电,为未来超高比例新能源新型电力系统的构建提供借鉴参考。

关键词：超高比例新能源弱电网电力电量平衡暂态建模仿真多元储能构网控制

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