Speciation and thermal transformation of sulfur forms in high-sulfur coal and its utilization in coal-blending coking process:A review

The utilization of high-sulfur coal is becoming more urgent due to the excessive utilization of low-sulfur,high-quality coal resources,and sulfur removal from high-sulfur coal is the most important issue.This paper reviews the speciation,forms and distribution of sulfur in coal,the sulfur removal from raw coal,the thermal transformation of sulfur during coal pyrolysis,and the sulfur regulation during coal-blending coking of high organic-sulfur coals.It was suggested that the proper characterization of sulfur in coal cannot be obtained only by either chemical method or instrumental characterization,which raises the need of a combination of current or newly adopted characterization methods.Different from the removal of inorganic sulfur from coal,the organic sulfur can only be partly removed by chemical technologies;and the coal structure and property,particularly high-sulfur coking coals which have caking ability,may be altered and affected by the pretreatment processes.Based on the interactions among the sulfur radicals,sulfur-containing and hydrogen-containing fragments during coal pyrolysis and the reactions with minerals or nascent char,regulating the sulfur transformation behavior in the process of thermal conversion is the most effective way to utilize high organic-sulfur coals in the coke-making industry.An in-situ regulation approach of sulfur transformation during coal-blending coking has been suggested.That is,the high volatile coals with an appropriate releasing temperature range of CH4 overlapping well with that of H2 S from high organic-sulfur coals is blended with high organic-sulfur coals,and the C–S/C–C bonds in some sulfur forms are catalytically broken and immediately hydrogenated by the hydrogencontaining radicals generated from high volatile coals.Wherein,the effect of mass transfer on sulfur regulation during the coking process should be considered for the larger-scale coking tests through optimizing the ratios of different coals in the coal blend.

Chemical composition and sulfur forms in saline lakes of Kulunda Plain(Russia)

1 Introduction On the territory Kulunda Plain,located to the south-west of the Ob’plateau,there are more than 3,000 fresh and salt lakes with water TDS range from 1 to 430 g/L.The interest in these lakes was associated mainly with the study of

Changes in sulfur form during coal desulfurization with microwave:Effect on coal properties

The changes in sulfur form in coal were analyzed by sulfur K-XANES(K-edge X-ray absorption near edge structures) spectra before and after the coal microwave desulfurization in a Na OH solution. After the desulfurization, the pyritic sulfur content of coal decreased significantly from 53.6% to 39.2%, while the sulfate sulfur content increased from 17.3% to 34.6%. Only a small amount of thiophene sulfur(20.1–16.1%) was removed. Some sulfur-containing components were oxidized to sulfate sulfur. Under the optimum conditions, the ash content decreased, while the volatile content increased. The calorific value of coal slightly decreased with a slight variation in the amplitudes. The overall structure of coal did not change significantly based on Fourier transform infrared(FTIR) spectral analyses. Thus, the desulfurization of coal with microwave irradiation in a Na OH solution did not significantly change the properties of coal.

Sulfur isotopic composition of the Tianqiao Pb-Zn ore deposit,Northwest Guizhou Province,China:Implications for the source of sulfur in the ore-forming fluids

The Tianqiao Pb-Zn ore deposit of Guizhou Province, China, is located in the mid-east of the Sichuan-Yunnan-Guizhou Pb-Zn-Ag multi-metallic mineralization area, which is representative of the Pb-Zn ore de-posits in this area. It consists of three main orebodies, whose Pb+Zn reserves are more than 0.2 million ton. This paper analyzes the sulfur isotopic composition of these orebodies. The data show that the ore minerals (galena, sphalerite, pyrite) in these orebodies are enriched in heavy sulfur, with δ34SV-CDT values varying between 8.35‰ and 14.44‰, i.e. the δ34SV-CDT values of pyrite are between 12.81‰ and 14.44‰, the mean value is 13.40‰; the δ34SV-CDT values of sphalerite are range from 10.87‰ to 14.00‰, the mean value is 12.53‰; the δ34SV-CDT values of galena are range from 8.35‰ to 9.83‰, the mean value is 8.84‰, and they have the feature of δ34Spyrite>δ34Ssphalerite>δ34Sgalena, which indicates the sulfur isotope in ore-forming fluids has attained equilibrium. The δ34S V-CDT values of the deposit are close to those of sulfates from carbonate strata of different ages in the ore-field (15‰), which suggests that the sulfur in the ore-forming fluids should be derived from the thermo-chemical sulfate reduction of sulfates from the sedimentary strata.

Sulfur isotopic composition of the Bainiuchang super-large Ag polymetallic deposit,Yunnan Province,China: Implications for the source of sulfur in ore-forming fluids

The Bainiuchang deposit in Yunnan Province, China, is located geographically between the Gejiu ore field and the Dulong ore field. In addition to >7000 t Ag reserves, the deposit possesses large-scale Pb, Zn, Sn reserves and a mass of dispersed elements (i.e., In, Cd, Ge, Ga, etc.). Based on systematic studies of sulfur isotopic composition, the authors conclude: The Bainiuchang deposit experienced two epochs of metallogenesis, i.e., the Middle-Cambrian sea-floor exhalative sedimentary metallogenic epoch and the Yanshanian magmatic hydrothermal superimposition metallogenic epoch. In the two metallogenic epochs, the δ34S values of sulfides were all near 0, showing a tendency of being enriched slightly in heavy sulfur. The δ34S values of sulfides in the early metallogenic epoch are within the range of 2‰–5‰ with a peak value range of 2‰–3‰ and an average of 3.0‰, and those of sulfides in the late metallogenic epoch are within the range of 2‰–6‰ with a peak value of 3‰–4‰ and an average of 3.9‰. For the single metallogenic epoch, sulfur in the ore-forming fluids in the early epoch already reached isotopic equilibrium and was derived mainly from underneath the magma chamber or basement metamorphic igneous rocks. Sulfur in the sulfides in the late epoch was derived mainly from magmatic hydrothermal fluids formed in the process of remelting of the basement metamorphic igneous rocks.

利用纤维素工业废丝/胶高效制备再生纤维素纳米晶

为解决再生纤维素工业丝的废丝以及生产过程中的废丝/胶的再利用问题,设计了以再生纤维素工业废丝或废丝/胶为原料高效制备再生纤维素纳米晶(RCNC)的方法,并通过傅里叶变换红外光谱、马尔文激光粒度仪、扫描电子显微镜、X射线衍射和原子力显微镜等方法,对比了利用新溶剂法再生纤维素工业废丝/胶、粘胶再生纤维素工业废丝和浆粕制得的RCNC、CNC的结构性能上的区别。结果表明:新溶剂法再生纤维素工业丝废丝/胶高取向度、高结晶度和结构简单的特性使其可以在更温和的条件下酸解,制备的RCNC得率高达到65.09%,远大于以浆粕为原料制备CNC的得率,且具有更高的结晶度。与粘胶纤维素工业废丝制得的RCNC相比,两者具有相似的尺寸与形貌,都为纳米级的棒状结构,长度和长径比分别为93 nm±26 nm和35±20,表明此方法对于不同来源的纤维素工业丝废丝具有一定的普适性。

Geology and sulfur isotope geochemistry of Dafulou tin-polymetallic deposit in Dachang orefield, Guangxi, China

No. 22 ore of Dafulou deposit was systematically analyzed for sulfur isotopes. The results show that the δ34S values of sulfide minerals, ranging from 0.154 to +0.218% and with an average value of +0.114 1%, are mostly positive and characterized by rich sulfur(S) content. This suggests that the sulfur of the Dafulou ore deposit is derived from magma and relates to the Longxianggai concealed granite, which points to the important role of magma during mineralization and implyies the product of the active continental margin. By comparison between the Dafulou and the Kengma tin deposit, significant differences exist in the sulfur isotope composition. In the Kengma deposit, the sulfur isotope composition is characterized by the high negative value, which is different from the Dafulou tin-polymetallic deposit. The difference of the enrichment and fractionation of the sulfur isotope is the synthesized result of the metallogenic conditions. It also has the difference in the metallogenic environment and metallogenic characteristics of the deposit in the same ore belt.

Recent progress in fluorinated electrolytes for improving the performance of Li–S batteries

Lithium–sulfur(Li–S) batteries represent a "beyond Li-ion" technology with low cost and high theoretical energy density and should fulfill the ever-growing requirements of electric vehicles and stationary energy storage systems. However, the sulfur-based conversion reaction in conventional liquid electrolytes results in issues like the so-called shuttle effect of polysulfides and lithium dendrite growth, which deteriorate the electrochemical performance and safety of Li–S batteries. Optimization of conventional organic solvents(including ether and carbonate) by fluorination to form fluorinated electrolytes is a promising strategy for the practical application of Li–S batteries. The fluorinated electrolytes, owing to the high electronegativity of fluorine, possesses attractive physicochemical properties, including low melting point,high flash point, and low solubility of lithium polysulfide, and can form a compact and stable solid electrolyte interphase(SEI) with the lithium metal anode. Herein, we review recent advancements in the development of fluorinated electrolytes for use in Li–S batteries. The effect of solvent molecular structure on the performance of Li–S batteries and the formation mechanism of SEI on the cathode and anode sides are analyzed and discussed in detail. The remaining challenges and future perspectives of fluorinated electrolytes for Li–S batteries are also presented.

三峡库区沉积物还原性无机硫形态的分布特征、控制因素及对内源磷释放的影响

还原性无机硫(RIS)包括硫酸盐还原产物和活性铁(FeHR)形成的酸可挥发性硫(AVS)、硫的中间产物元素硫(S0)及沉积物中硫铁元素的最终积累物质黄铁矿硫(Spy),RIS不仅可以影响沉积物重金属的生物有效性,还控制铁还原及内源磷的释放等生源要素的地球化学行为。为了研究三峡库区沉积物中RIS分布特征及其环境意义,于2017年7—8月和12月采集三峡库区云阳至秭归段17个点的表层沉积物样品并测定其RIS含量。结果表明:与其他湖泊、河流相比,三峡库区表层沉积物RIS含量较低,其中,AVS的含量为0.06~0.65μmol/g,S0为0.50~1.66μmol/g,Spy为0.96~17.54μmol/g.AVS和S0含量夏季高于冬季,云阳至秭归段RIS变化趋势大致为先降低后增加再降低,有较明显的季节和地域差异。相关性分析、主成分分析和聚类分析表明,研究区沉积物生物可利用磷(BAP)、FeHR及上覆水体SO42-含量为沉积物RIS的主要限制因子。库区冬季RIS与有机磷(Org-P)和可交换态磷(Ex-P)呈显著相关性,当硫化物含量增加时,会促进Org-P的矿化分解和Ex-P向上覆水体迁移,增加释磷风险。同时,本研究从硫驱动富营养化的角度评估了三峡库区存在污染风险的水域。除库区内已发生过典型水华的重点支流外,长滩河和九畹溪也存在富营养化问题。

喀斯特湿地转变为农用地对土壤有机硫形态及芳基硫酸酯酶活性的影响

【目的】土壤有机硫形态及芳基硫酸酯酶活性能敏感地反映土壤硫库的变化,厘清喀斯特湿地转变为农用地后不同土地利用方式下土壤有机硫形态和芳基硫酸酯酶活性的变化特征及其影响因素,对喀斯特湿地土地合理利用和土壤质量管理具有重要意义。【方法】以典型桂林会仙喀斯特天然沼泽湿地为对照(沼泽湿地),以由其转变而来的5种土地利用方式,即水稻田、旱地、果园、养殖地和弃耕地为研究对象,采集0—10、10—20、20—30和30—40 cm共4个土层的样品,分析各形态有机硫含量及芳基硫酸酯酶活性。【结果】1)与沼泽湿地相比,5种土地利用方式的土壤全硫储量、酯键硫、碳键硫以及残渣态硫含量均呈降低趋势。5种土地利用方式土壤碳键硫、酯键硫和残渣态硫占有机硫的比例分别为39.08%~63.54%、22.91%~34.28%、13.55%~28.46%,与沼泽湿地相比,酯键硫和残渣态硫占比降低,碳键硫占比升高(P<0.05)。2)沼泽湿地土壤有机硫含量范围在158.41~442.18 mg/kg,全硫含量范围在180.22~510.83 mg/kg,全硫平均值为345.53 mg/kg,低于世界土壤全硫含量均值(700 mg/kg)。不同土地利用方式下,0—40 cm土层土壤全硫和有机硫含量均值大小整体表现为:湿地>水稻田>旱地>养殖地>果园>弃耕地,湿地与其他土地利用方式间存在显著差异(P<0.05)。3)在0—40 cm土层中,不同土地利用方式下土壤芳基硫酸酯酶活性均随土层深度的增加而降低。相较于沼泽湿地,5种土地利用方式的土壤芳基硫酸酯酶活性均降低,水稻田、旱地、果园、养殖地和弃耕地降幅分别为18.19%、27.48%、39.72%、33.81%和51.77%(P<0.05)。【结论】会仙喀斯特天然湿地转变为其他土地利用方式后,土壤全硫和有机硫含量显著下降(P<0.05),全硫含量(98.06~222.87 mg/kg)小于我国南方10省耕作层土壤全硫平均值(299 mg/kg)。土壤有机碳、全氮、含水量和芳基硫酸酯酶是土壤有机硫形态含量的主要影响因素。因此,减少湿地人为垦殖,有利于维持会仙喀斯特湿地土壤养分的平衡与生态系统的健康。

西藏拿若铜(金)矿床硫、铅同位素组成及成矿物质来源

为探讨多龙矿集区拿若铜(金)矿床的成矿物质来源,研究矿床成矿机制,本文在详细的野外地质调查和矿石学研究基础上对矿石样品进行硫和铅同位素分析,并对成因意义进行讨论。研究结果表明,17件金属硫化物的δ^(34)S值变化于-2.3‰~2.3‰之间,均值为-0.1‰;其中13件黄铁矿δ^(34)S值变化范围为-2.3‰~2.3‰,均值为0.2‰;4件黄铜矿的δ^(34)S值变化范围为-1.5~-0.8‰,均值为-1.1‰。δ^(34)S值频率直方图总体具有塔式分布特征,平均值接近于零,具幔源硫特征。金属硫化物的^(208)Pb/^(204)Pb介于38.209~38.854之间,平均值为38.635;^(207)Pb/^(204)Pb变化范围为15.541~15.665,平均值为15.605;^(206)Pb/^(204)b为17.942~18.580,平均值为18.461,具有正常铅的特征。铅同位素μ值变化范围为9.40~9.57,均小于9.58,表明矿床铅主要来自幔源物质。拿若矿床的硫和铅同位素特征与多龙矿集区斑岩型矿床类似,成矿物质主要来源于岛弧环境下幔源物质,可能存在壳源物质的混入。

西藏洞嘎金矿床地质特征、原位硫同位素组成及成因探讨

洞嘎金矿位于西藏雄村矿集区,是冈底斯成矿带较早发现且投入开采的金矿,但研究程度低,矿床成因存在较大争议。本文通过系统的矿床地质特征研究,开展了硫化物原位硫同位素测试,分析成矿物质来源,进而探讨洞嘎金矿的成因。洞嘎金矿体受控于雄村组凝灰岩中的裂隙系统,矿体呈脉状产出,已探获金金属资源量9.55 t,达到中型规模。矿石构造主要为脉状-细脉状构造,金主要以包裹金和粒间金的形式赋存于黄铁矿和黄铜矿中。根据脉体穿插关系及矿物共生组合特征,将洞嘎金矿的成矿过程划分为热液成矿期与表生氧化期,其中热液成矿期为主成矿期,可进一步划分为3个成矿阶段:成矿早阶段、成矿主阶段及成矿晚阶段。洞嘎金矿床硫化物的硫同位素δ^(34)S=–1.57‰~+5.26‰,平均值+1.69‰,具明显的塔式分布,表明硫源具岩浆硫的特点。结合前人已发表的数据,我们认为洞嘎金矿属于斑岩铜金成矿系统外围的热液脉型金矿床,深部可能存在斑岩型铜金矿床,找矿潜力极大。洞嘎金矿的成矿物质来源主要为地幔,有少量的地壳物质(俯冲沉积物)加入。洞嘎金矿床的金与绿泥石密切相关,该绿泥石主要为溶蚀-迁移-结晶机制形成,绿泥石形成过程导致含金热液流体成分及物理化学性质发生改变,使得成矿流体中的金发生卸载,最终在凝灰岩的裂隙系统中形成洞嘎金矿床。

基于高硫煤不同添加比例的配煤炼焦试验研究

合理利用不同类型的高硫炼焦煤资源以及提升其在炼焦配煤中的比例,其为实现炼焦过程中降本增效的有效手段。以工业实际生产炼焦配煤为基础,分别选取1种高硫焦煤和高硫肥煤,利用工业分析、黏结指数、胶质层指数、吉氏流动度、奥阿膨胀度等分析高硫煤与基础配煤中低硫煤的基本煤质特性,利用X射线光电子能谱(XPS)、红外光谱(FTIR)、核磁波谱(^(13)C NMR)分析确定不同炼焦煤的硫赋存形态及碳结构参数,利用40 kg焦炉炼焦试验对比分析不同比例高硫煤的配入对配煤焦炭质量的影响。结果表明,高硫焦煤和肥煤碳结构中的脂肪链长度较长,使得成焦过程中能够分解产生更多的含氢基团,软化熔融产生的胶质体的流动性好、塑性温区宽,能够与配煤中其他煤种进行更有效黏合。高硫焦煤和肥煤中硫化物、亚砜、砜等形态硫在炼焦过程中分解及与含氢组分结合生成的含硫气体随挥发分释放,单独炼焦脱硫率分别达到32.78%和42.61%。炼焦配煤中高挥发分、高流动度的高硫肥煤配入比例过高,成焦过程膨胀压力、焦炭收缩应力、焦炭孔隙率的增加,使焦炭强度出现下降。高硫焦煤和高硫肥煤分别以2%和3%配入炼焦配煤,得到焦炭的机械强度与基础焦炭相近,但反应后强度提升至56.0%。

铜陵天马山硫金矿床矽卡岩矿物学特征及矿石硫同位素地球化学研究

天马山硫金矿是铜陵矿集区典型的层控热液叠加改造型矿床,层状矿体中发育大量的矽卡岩矿物。为查明该矿床中矽卡岩矿物的类型及形成环境,探讨矽卡岩与硫、金成矿之间的关系,对主要的矽卡岩矿物开展了矿物学及矿物化学研究,并对矿石进行了硫同位素地球化学研究。研究表明:矿区内的矽卡岩矿物以石榴子石和辉石为主,其中石榴子石以钙铁榴石为主,属于钙铁榴石-钙铝榴石固熔体系列(Gro 0~18.73 And 80.54~99.00 Spe+Pyr+Alm 0.54~1.47);辉石以透辉石为主,其次为钙铁辉石,属于透辉石-钙铁辉石系列(Di 62.35~97.65 Hd 1.89~36.27 Jo 0.31~1.55)。天马山硫金矿的矿物组合(钙铁辉石+透辉石)属于氧化型矽卡岩,表明矽卡岩形成于相对高温和高氧逸度的条件。石榴子石和辉石端元组分特征及辉石Mn/Fe值(0.02~0.07)具有典型的矽卡岩型铜、金矿床特征。矿石硫同位素具有岩浆源的特征,与区内燕山期岩浆-成矿作用形成的矿石一致,而明显区别于喷流-沉积作用形成的矿石,显示成矿作用与燕山期岩浆活动具有密切的成因联系。燕山期中酸性岩浆交代碳酸盐岩围岩形成大量矽卡岩,矽卡岩矿物的形成增加了岩石的孔隙度和渗透率,为晚期硫、金矿床的形成提供了有利条件。

湘东北正冲金矿床成因:年代学和硫同位素制约

正冲金矿床是湘东北地区典型的金矿床,其矿体受NNE和NW向2组断裂控制,赋存于低变质程度的冷家溪群中,矿床成矿时代和成矿物质来源尚存在争议。借助LA-(MC)-ICP-MS分析方法,对正冲金矿床中含金石英脉中的绢云母进行原位Rb-Sr定年和黄铁矿原位S同位素分析,以确定其成矿时代和成矿物质来源,进而明确矿床成因。绢云母原位Rb-Sr定年结果显示:正冲金矿床的年龄在(219.1±6.0)~(215.8±7.7)Ma之间,黄铁矿的δ^(34)S值(-3.85‰~1.95‰)接近于0,且具有由负值向正值移动的趋势,表明深部岩浆(或幔源物质)可能是正冲金矿床成矿物质的主要来源,有少量地层物质参与成矿。结合矿床地质特征、成矿年代学和硫同位素地球化学特征,认为正冲金矿床形成于印支期陆内造山环境下,属于与深部岩浆活动有关的金矿床。

宁东煤田红墩子矿区煤中硫分布特征及成因分析

宁夏油气资源贫乏,宁东能源化工基地高速发展,煤炭资源需求逐年增大。红墩子矿区是宁东能源化工基地的重要原煤产地,但矿区高硫煤资源量占矿区煤炭总资源量的13.56%,很大程度上限制了煤炭资源的开发与利用,因此开发利用高硫煤是解决宁东地区能源安全及保障能源供应的重要途径。在利用煤炭勘查及相关研究成果资料的基础上,完成了红墩子矿区煤岩层对比,分析了矿区各成煤时代的沉积环境及古地理特征,揭示了煤中硫空间非均质性的分异机制及赋存特征。结果表明:从平面分布来看,山西组4煤为低硫煤,原煤全硫(S_(t,d))为0.07%~2.05%,平均0.74%,呈北高南低的分布态势;太原组8煤为中高硫煤,原煤全硫(S_(t,d))平均2.58%,高硫煤零星分布,矿区中部和西部地区中高硫煤分布较广;太原组9煤原煤全硫(S_(t,d))平均2.49%,矿区东部硫分整体较高,高硫煤分布于东部及南部。矿区内煤中硫分的富集整体呈由东向西的迁移规律。从形成时代来看,山西组到太原组的煤中硫含量显著增加,体现了煤中硫分的富集受海相沉积和陆相沉积的差异影响。

贵州织金县以那地区龙潭组煤质特征及其沉积环境指示

成煤环境与煤质特征关系紧密,泥炭沼泽期陆源输入强度、海水进退以及氧化还原条件对煤中元素分布和组成具有重要影响。本次研究利用贵州织金县以那地区三个煤矿勘查区共46口钻孔主采煤层的煤质分析结果,分析了龙潭组自下而上煤质参数分布特征,并在此基础上探讨了硫分和灰成分指数对成煤环境的指示作用。研究结果表明:(1)以那地区无烟煤全硫分含量较低,平均为2.19%,以无机硫为主,煤灰分中主量元素以SiO_(2)为主,Al_(2)O_(3)和Fe_2O_(3)次之,其他含量较低;(2)各煤层全硫含量、有机/无机硫在全硫中占比、主量元素组合(Fe_2O_(3)+CaO+MgO和SiO_(2)+Al_(2)O_(3))含量呈现相互匹配的变化规律,煤灰成分指数变化规律不明显;(3)以那地区龙潭组自下而上经历了三期海水进退过程,发育潮坪下三角洲平原、三角洲分流间湾和潮坪-瀉湖三种成煤环境,硫分与灰成分指数在成煤环境指示作用上具有较好的一致性。

不同填料对硫自养反硝化深度脱氮效能的影响研究

利用硫自养反硝化工艺提高餐厨垃圾沼液MBR尾水水质。利用自然挂膜的方式启动硫自养反硝化滤池,考察不同成型方式的硫质填料对餐厨垃圾沼液MBR尾水脱氮效果的影响。粉末压制成型的硫质填料相较于熔融滴制成型的硫质填料,其启动速度更快、脱氮和COD降解效能更高、消耗的碱度更少,且强度大于35 N粉末压制成型的硫质填料不会影响实际运行,因而其更适合作为硫自养填料用于餐厨垃圾沼液MBR尾水处理。此外,利用自然挂膜的方式启动硫自养反硝化滤池能富集95%以上的反硝化菌种,装置实际运行中自养反硝化菌Thiobacillus和Sulfurimonas属于优势菌,总氮去除率可达到90%以上。

新安煤田深部煤中硫分布特征及成煤环境分析

新安煤田位于河南省西部,处于太行构造区、嵩箕构造区和崤熊构造区交界部位,煤田主体位于太行构造区内。为了解新安煤田深部煤中硫分布特征及成煤环境,对研究区二_(1)、二_(2)煤层硫分含量的进行了分析和归纳,阐述了二_(1)、二_(2)煤层硫含量特征以及硫分平面分布特征。根据煤中各形态硫所占比例以及成因,探讨了煤层中硫分布特征及成煤环境。结果表明,二_(1)煤层贫煤以中—中高硫煤为主,无烟煤原煤以低—中高硫煤为主;二_(2)煤层贫煤以低—中硫煤为主,无烟煤以低—中高硫煤为主。二_(1)、二_(2)煤层煤中硫以硫化铁硫为主,占全硫的60%~90%。山西组成煤环境为浅水河流和海水潮汐共同控制的三角洲沉积体系,煤层的形成受淡水和海水的双重影响。

西藏那不定铅锌矿床S、Pb、H、O同位素组成及成矿物质来源示踪

西藏那不定铅锌矿床位于冈底斯成矿带中东段,是新发现的矽卡岩型铅锌矿床,目前研究程度较低。本文在野外地质调查的基础上,运用S、Pb同位素研究方法,对那不定铅锌矿床的物质来源进行初步的探讨。结果显示:(1)那不定铅锌矿石金属硫化物的δ^(34)SV-CDT值分布范围较宽,主要集中在-2.0‰~6‰之间,在硫同位素直方图上呈塔式分布,总体具有黄铁矿>闪锌矿>方铅矿的特征;(2)铅同位素组成比较均一,同位素比值变化较小,显示出普通铅的特征,显示出铅同位素来源以上地壳铅为主,少量造山带铅相结合的特征;(3)将那不定矿床6件脉石矿物中石英包裹体氢同位素值在-83.5‰~167.8‰之间,石英包裹体中δ^(18)O水‰值在-2.81‰~3.6‰范围内,显示明显受到大气降水加入。