Occurrence state and oil content evaluation of Permian Fengcheng Formation in the Hashan area as constrained by NMR and multistage Rock-Eval

The Hashan area,neighboring the Mahu Sag that is rich in the shale oil resources,showed commercial oil flow in the corresponding lacustrine shales of the Lower Permian Fengcheng Formation(P)with reserve scale approximately 789 million tons,presenting great potential for oil exploration.Despite their geographical proximity,the hydrocarbon occurrence and oil-bearing capacity of shale in the Hashan area and Mahu Sag greatly differ owing to the complex tectonic evolution.Therefore,understanding the occurrence state and oil content of the Pif in the Hashan area is crucial for ongoing shale oil exploration activities and the development of the northwestern margin of the Junggar Basin.In this study,an in-tegrated investigation,including petrological observations,scanning electron microscopy(SEM)obser-vation,analysis of nuclear magnetic resonance(NMR)Ti-T2 spectra,and conventional and multistage Rock-Eval pyrolysis methods were conducted to evaluate the occurrence state and oil content of the Pif shale in the Hashan area.The results indicate that plagioclase(average 30.7%)and quartz(24.1%)dominate the mineral compositions of the Pf shale samples.A method involving quartz-plagioclase-carbonate minerals is proposed to conduct lithofacies classification.In the Hashan area,the organic matter abundance in the Pf shale is scaled in fair to good range,the thermal maturity ranges from immature to early mature stage,and the primary organic matter types are Types I and Ilj.Intergranular and dissolution pores are the two most common pore types.The free oil is mostly found in the pores and microfractures of the mineral matrix,whereas the adsorbed oil is mostly adsorbed on the surfaces of kerogen and clay minerals.The high organic matter abundance,quartz content,and porosity account for substantial increase in the oil content,the area rich in shale oil resources coincides with that rich in free oil.The most favorable lithofacies in the Hashan area is the calcareous mudstone/shale,which hosts the highest free oil content(average 2.49 mg),total oil content(15.02 mg/g),organic matter abundance CTOC:1.88% and S_(1)+S_(2)=20.54mg/g and orositv(5.97%)

Study on the occurrence state of indium in sphalerite of Dulong Sn–Zn–In polymetallic deposit,Southwest China

The Dulong deposit,located in the Laojunshan area of southeastern Yunnan,China,is an important polymetallic deposit due to its high reserves of tin,zinc,and indium.The occurrence state of indium is critical for understanding its supernormal enrichment mechanism.Previous studies investigated the occurrence state of indium(including the valence state)based on the indium content in sphalerite and the correlation between metal concentrations.However,more evidence is needed to better constrain indium occurrence at the micro-,nano-,or even atomic scale.In this study,EPMA-FIB-SEM-TEM and XPS techniques were employed to investigate the indium distribution characteristics and occurrence state in sphalerite from the Dulong Sn–Zn–In polymetallic deposit.The maximum concentration of indium in the indium-rich sphalerite samples is 0.37%,and the results of the EPMA analysis showed a relatively homogeneous distribution of indium in sphalerite.The FIB-SEM-TEM results demonstrated that the lattice stripes of sphalerite were periodically and continuously distributed at the nanoscale,confirming that sphalerite in the deposit was an excellent single crystal structure,and the peak heights of the various characteristic peaks of indium in the EDX spectra were relatively close to each other,with no distinct peaks of high indium content.In addition,the XPS results indicate that the element valence state of indium in sphalerite is In^(3+),and it combines with S^(2-)to form a bond.These results indicate that indium in sphalerite of the Dulong deposit is uniformly distributed at both the micro-and nanoscale,and there is no indium-independent mineral.In^(3+)enters the crystal lattice of sphalerite by replacing Zn2+in the form of isomorphic substitution.

Microscopic oil occurrence in high-maturity lacustrine shales:Qingshankou Formation,Gulong Sag,Songliao Basin

Occurrence and mobility of shale oil are prerequisites for evaluating shale oil reserves and prioritizing exploration targets,particularly for heterogeneous lacustrine shales.The Qingshankou Formation in the Gulong Sag,Songliao Basin is a classic lacustrine pure shale reservoir that contains abundant shale oil resources.The predicted geological reserves of the shale are 1.268×10^(9) t.In this study,field emission scanning electron microscope(FE-SEM),the modular automated processing system(MAPS),pyrolysisgas chromatography(Py-GC),low-pressure nitrogen gas adsorption(LPNA),Soxhlet extraction,pyrolysis,and 2-D nuclear magnetic resonance(NMR)were integrated to describe the shale oil components,microscopic occurrence,mobility,and the effective pore size distribution.Meanwhile,the related controlling factors are discussed.The shale oil in the Qingshankou Fm exists dominantly in the matrix pores of the clay minerals,with small amounts distributed in the intergranular pores of terrigenous clastic grains,intercrystalline pores of pyrite,intragranular pores of ostracod shells,and micro-fractures.Shale oil is distributed in the pore spaces of variable sizes in different lithofacies.The clay mineral-laminated shales are characterized by the broadest range of pore size and largest volume of pore spaces with shale oil distribution,while the ostracod-laminated shales have limited pore spaces retaining oil.Furthermore,the proposed integrated analysis evaluates the shale oil molecules existing in two states:movable,and adsorbed oil,respectively.The result illustrates that movable oil takes up 30.6%e79.4%of the total residual oil.TOC,mineral composition,and pore structures of the shale joint together to control the states and mobility of the shale oil.TOC values are positively correlated with the quantities of shale oil regardless of the state of oil.The mineral components significantly impact the state of shale oil.Noticeable differences in the states of oil were observed following the changing types of minerals,possibly due to their difference in adsorption capacity and wettability.Clay minerals attract more adsorbed oil than movable oil.Felsic minerals generally decrease the occurrence of total and adsorbed oil.Carbonate plays a positive role in hydrocarbon retention of all the shale oil states.As for the pore structure,the average pore size exerts a critical impact on the total,movable,and adsorbed oil content.The total pore volume and specific surface area of shales play a principal role in controlling the total yields and amounts of adsorbed oil.This research improves the understanding of the occurrence characteristics and enrichment mechanisms of shale oil in terrestrial pure shales and provides a reference for locating favorable shale oil exploration areas.

Control of micro-wettability of pore-throat on shale oil occurrence:A case study of laminated shale of Permian Lucaogou Formation in Jimusar Sag,Junggar Basin,NW China

The control of micro-wettability of pore-throat on shale oil occurrence in different types of reservoir spaces remains unclear.Take the shale oil reservoir of the Permian Lucaogou Formation in the Jimusar Sag,Junggar Basin as an example,the reservoir space in laminated shale and the control of micro-wettability of pore-throat on shale oil occurrence were studied by using scanning electron microscope(SEM),multi-stage pyrolysis,quantitative fluorescence,nuclear magnetic resonance(NMR)and other techniques.The results show that there are mainly two types of laminated shale in the Lucaogou Formation,namely laminated shale rich in volcanic materials+terrigenous felsic,and laminated shale rich in volcanic materials+carbonate.The former type contains feldspar dissolution pores and intergranular pores,mainly with felsic mineral components around the pore-throats,which are water-wet and control the free shale oil.The latter type contains carbonate intercrystalline pores and organic pores,mainly with oil-wet mineral components around the pore-throats,which control the adsorbed shale oil.The oil-wet mineral components around the pore-throats are conducive to oil accumulation,but reduce the proportion of free oil.In the Lucaogou Formation,free oil,with high maturity and light quality,mainly occurs in the laminated shale rich in volcanic materials+terrigenous felsic.

Analysis of the microstructure and elemental occurrence state of residual ash-PM following DPF regeneration by injecting oxygen into non-thermal plasma

Particulate matter(PM)capture tests were carried out on clean diesel particulate filters(DPFs)under different loads(25%,50%,75%and 100%).DPFs were regenerated by a non-thermal plasma(NTP)injection device.Raman spectroscopy and x-ray photoelectron spectroscopy were used to investigate changes in the microstructure and element occurrence state of the sediment in DPF channel before and after regeneration.The order of the PM samples decreased before NTP treatment as the load increased;the amorphous carbon content was high,and the oxidationactivity was higher.After NTP treatment,the carbon atoms at the edge of the microcrystalline structure in the ash-PM samples were oxidized,and the structure was reorganized;in addition,the amorphous carbon content decreased,and the structure was more diversified.Before NTP,the C element of PM samples was the main component,and the content of the O element was relatively low.The C element occurred in the form of C–C,C–OH,and O–C=O functional groups,and O atoms were mainly combined with C–O.After NTP,the content of Na,P,S,Ca,and other inorganic elements in ash-PM samples was prominent because C atoms were removed by NTP active substances.There were two forms of S element occurrence(SO42-and SO32-);the proportion of SO42-was approximately 40%,and the proportion of SO32-was approximately60%.Study of the microstructure and element occurrence of the residues in the DPF channels improved our understanding of the mechanism of the low-temperature regeneration of DPFfrom NTP.

Chemical composition of the ore and occurrence state of the elements in Jingbaoshan platinum-palladium deposit

The Jingbaoshan platinum-palladium deposit is China’s largest independent PGM (platinum-group met- als) deposit so far discovered. There are eleven kinds of useful components in the ore: Pt, Pd, Os, Ir, Ru, Rh, Au, Ag, Cu, Ni, and Co. The platinum-group elements, gold and silver occur in the form of minerals in ores. twenty-five kinds of precious metal minerals have been found, of which twenty one belong to the platinum-group minerals. The minerals are very small in grain size. Copper occurs mainly as copper sulfide with a small amount of free copper oxide, and the beneficiated copper accounts for 95.21%. Nickel occurs mainly as nickel sulfide, and some nickel silicate and nickel oxide occur in the ore. The beneficiated nickel accounts for 72.03%. Cobalt occurs mainly as co- balt sulfide, and there are some cobalt oxide and other kinds of cobalt. The beneficiated cobalt accounts for 77.58%.

The occurrence state of vanadium in the black shale-hosted vanadium deposits in Shangling of Guangxi Province, China

The Shangling vanadium deposit, which occurs in the Lower Devonian Tangding formation black rock series strata, has V2O5 reserves of more than 1.5 million tons and prospective reserves of more than 2 million tons. Preliminary studies on the occurrence state of vanadium(V) in this deposit have been conducted by artificial heavy minerals concentrates, leaching experiments, scanning and transmission electron microscopy and X-ray powder diffraction.These experiments have revealed no independent vanadium mineral occurrences in the Shangling vanadium deposit and the percentages of water-soluble vanadium, hydrochloric acid soluble vanadium and HF soluble vanadium were1.93 %, 21.42 % and 76.47 %, respectively. Based on our data and earlier research, we estimate that the valences state of V absorbed onto the surface of organic matter or clastic particles are +5 and +4, accounting for 10.00 % and13.35 % of the total amount of V, respectively and the valences state of V that exist in the octahedral crystal lattice of authigenic illite include +3 and +4, accounting for71.64 % and 4.83 % of the total amount of V, respectively.By calculating the correlation between the total organic carbon and V, we infer that after deposition and before entering the crystal lattice of illite, V occurs in the form of humate complex or is adsorbed by organic matter. About4.24 % of the Al is in the octahedral crystal lattice of illite,which was replaced by the vanadium under the metallogenic environments of Shanglin.

THE INFLUENCEN OF STAND STATE ON THE OCCURRENCE OF DENDROLIMUS SUPERANS (BUTLER) IN DAXING'AN MOUNTAINS

Dendrolimus superans (Butler) occurred in the vast areas of Daxing'an Mountains forest. in Heilongjiang Province, in 1990. Stands damaged by D.Superans seriously, intermediately and lightly show patch shape distribution within damaged area. By ordination analysis and correlation analysis between ordination factors and coordinate axis. It was found that occurrence of D. Superans in different extent is owing to the effect of forest age. composition and exposure. The tended young pure forests grown on the sunward slopes are most seriously damaged and non-tended middle-age mixing stands grown on the sunless slopes are most lightly damaged. Therefore, in order to prevent D.superans from seriously damaging larch forests. relatively large crown density (P>0. 7) should be kept,and broadleaftrees should be also properly preserved.

The occurrences and geochemical characteristics of thorium in iron ore in the Bayan Obo deposit, Northern China

The Bayan Obo deposit in northern China is an ultra-large Fe–REE–Nb deposit.The occurrences,and geochemical characteristics of thorium in iron ores from the Bayan Obo Main Ore Body were examined using chemical analysis,field emission scanning electron microscopy,energy dispersive spectrometer,and automatic mineral analysis software.Results identified that 91.69%of ThO2 in the combined samples was mainly distributed in rare earth minerals(bastnaesite,huanghoite,monazite;56.43%abundance in the samples),iron minerals(magnetite,hematite,pyrite;20.97%),niobium minerals(aeschynite;14.29%),and gangue minerals(aegirine,riebeckite,mica,dolomite,apatite,fluorite;4.22%).An unidentified portion(4.09%)of ThO2 may occur in other niobium minerals(niobite,ilmenorutile,pyrochlore).Only a few independent minerals of thorium occur in the iron ore samples.Thorium mainly occurs in rare earth minerals in the form of isomorphic substitution.Analyses of the geochemical characteristics of the major elements indicate that thorium mineralization in the Main Ore Body was related to alkali metasomatism,which provided source material and favorable porosity for hydrothermal mineralization.Trace elements such as Sc,Nb,Zr,and Ta have higher correlation coefficients with thorium,which resulted from being related to the relevant minerals formed during thorium mineralization.In addition,correlation analysis of ThO2 and TFe,and REO and TFe in the six types of iron ore samples showed that ThO2 did not always account for the highest distribution rate in rare earth minerals,and the main occurrence minerals of ThO2 were closely related to iron ore types.

Mineral occurrence for Dachang gold deposit and its impact on gold recovery rate in Qumarleb County,Qinghai

Based on X-ray diffraction,optical microscopy and scanning electron microscopy analysis of the Dachang gold ore,it is showed that the sulfide of ore is the main carrier minerals of gold. A majority of gold is embedded in pyrite and tetrahedrite as the form of inclusion and a small amount intergrowth with pyrite and gangue mineral,occasionally the presence is in form of monomer natural gold. The main factors which influence the recovery rate are sulfide mineral particle size,and the fine grained sulfide is beneficial for the dissociation and flotation of gold bearing minerals. The monomer dissociation degree of gold bearing minerals can reach91. 3%,when the grinding fineness is less than 0. 074 mm and grain level accounts as 80%. It is not conducive to the flotation of sulfide if the grinding fineness is low or high. It is difficult to completely dissociate the monomer if there is a small amount of pyrite and arsenopyrite in the ore. Therefore,before leaching the gold,it must conduct pretreatment to reach the ideal recovery rate of the gold,like roasting oxidation,pressure oxidation and biological oxidation. The fine microscopic gold has little influence on the gold recovery rate.

利用AMICS测试技术分析冶炼矿渣中Cu-Co元素的赋存状态

铜作为一种战略资源,是支撑经济社会发展的工业金属;钴在保障我国战略性新兴产业发展、保障国家能源资源安全方面有着非常重要的意义。采用矿物自动定量分析系统(AMICS)结合化学分析、化学物相、扫描电镜(SEM)及能谱仪(EDS)等多手段,系统地对某铜钴精矿冶炼渣进行工艺矿物学分析。在查明了矿渣的化学成分、组分组成、颗粒嵌布与结晶特征、粒度分布等关键信息的同时,对制约和影响其中Cu、Co元素提取利用的矿物学因素进行了分析。结果显示,经冶炼后的铜钴精矿渣组成现大多已不是矿物形态,而是由不同元素结合而成的“组分”;Cu元素的富集载体较多,主要以独立组分形式存在,而Co元素的赋存形式较为单一,且以类质同象替代形式为主。研究成果为矿渣的再利用提供理论参考依据,同时为同类型及相似类型的尾渣提供研究及利用思路。

湖北宜昌磷矿伴生稀土元素分布规律、赋存状态及其开发利用前景分析

【研究目的】湖北省宜昌磷矿中伴生有稀土元素,研究其分布规律及赋存状态,对稀土元素的回收利用具有重要意义,其作为伴生矿产的综合利用将成为未来稀土矿的重要来源。【研究方法】本文以含稀土磷块岩为主要研究对象,在系统取样的基础上,开展岩矿鉴定、全岩地球化学分析、XRD衍射分析、SEM观察、LA-ICP-MS测试等工作。【研究结果】磷块岩中稀土元素总量ΣREE+Y为63.5×10^(-6)~271.8×10^(-6),不同层位或不同岩性的磷块岩中稀土元素含量有所差异。【结论】稀土元素含量受岩性控制明显,由白云岩→白云质磷块岩→致密块状磷矿石→泥质条带磷块岩→泥岩,含量逐渐升高。微量元素反映出宜昌磷矿的古气候以干热为主,西北部略表现出温暖湿润特点;Ce异常、V/Ni和Y/Ho比值反映海水中EH条件从底部到顶部,即从Ph22成磷期到Ph13成磷期,形成水体环境逐渐氧化。宜昌磷矿中稀土元素总量整体较低,且泥岩较磷块岩中含量高,表明吸附态稀土较类质同象稀土含量高。宜昌伴生稀土磷矿资源丰富,利用合理的技术对稀土元素进行综合回收,对宜昌磷矿资源的合理利用和经济发展有重要意义。

大宝山含钨褐铁矿中钨的赋存状态与嵌布特征

通过多种分析方法,探究广东大宝山含钨褐铁矿的物相组成、元素分布等工艺矿物学特征,以揭示矿石中关键金属钨的赋存状态与嵌布特征。X射线荧光分析(XRF)、粉末X射线衍射(XRD)以及扫描电子显微镜和能谱(SEM-EDS)结果表明:矿石中主要矿物为含钨褐铁矿和石英,关键金属钨品位为1.35%。微区X射线衍射(Micro-XRD)和矿物解离度分析仪(MLA)结果表明:钨主要赋存于高铁钨华((W,Fe)(O,OH)_(3))中,而高铁钨华则以剥离和带状形式紧密分布在褐铁矿中。同时,还定量分析了有价元素在各主要矿物中的赋存和分布情况,并讨论了含钨褐铁矿风化演变和形成机制。最终提出了一种选冶联合分选回收流程,为高效回收含钨褐铁矿中关键金属钨提供理论基础。

深层页岩纳米孔隙中气水微观动用机理

深层页岩气已成为我国天然气产量增长最现实的领域之一。已有研究结果证实深层页岩纳米孔隙发育,但页岩储层在高温高压含水条件下气水的动用复杂程度加剧。传统页岩岩心尺度的解吸和驱替实验成本高、周期长,难以解析纳米孔隙中气水在深层储层条件下的微观动用机理。为此,基于分子模拟方法,在考虑气水质量扩散传递的基础上,提出了1套页岩气水动用模拟方法,并模拟了深层页岩双重介质复合纳米孔隙中的甲烷和水分在2种不同模式下的动用机理,并量化了甲烷吸附气、溶解气和自由气,揭示了孔隙水和甲烷不同赋存状态的微观动用机理。研究结果表明:①页岩中伊利石对甲烷的亲和性强于干酪根,伊利石亲水性远大于干酪根;②2种动用模式下,伊利石中赋存的水分基本不发生动用,干酪根表面水分团簇可发生动用;③双重介质复合纳米孔隙中,甲烷的自由气动用率最大,溶解气和吸附气动用率较低,是后期页岩气储量挖潜的重要潜在资源。结论认为,深层页岩纳米孔隙中气水的微观动用理论研究对深层页岩气可采储量评估、产能评价和提高采收率等方面具有重要理论意义。

南襄盆地泌阳凹陷古近系核桃园组页岩含油性及烃类赋存特征

南襄盆地泌阳凹陷古近系核桃园组发育优质湖相页岩层系,页岩油资源潜力巨大。前人针对该层系页岩含油性及烃类赋存状态的研究相对薄弱,可能是制约泌阳凹陷页岩油勘探突破的重要因素之一。以泌阳凹陷南部Y1井核三段Ⅲ亚段页岩为研究对象,通过岩石热解、多温阶热解、X射线衍射等地球化学分析技术,系统开展了页岩含油性、烃类赋存特征及影响因素研究。研究结果显示:核三段Ⅲ亚段页岩岩相组合主要包括长英质页岩相、云灰质页岩相和混合质页岩相,纹层结构发育。烃源岩类型整体处于好—优质范围,热演化程度处于生油阶段。有机显微组分以腐泥型为主,有机质类型为Ⅰ—Ⅱ1型。页岩含油性随埋深增大呈递增趋势,烃类赋存特征由中上部以吸附烃为主,过渡至下部以游离烃为主。碎屑矿物及有机碳含量是控制游离烃和吸附烃含量的主要因素。总体认为,核桃园组下部页岩含油饱和度指数整体高于100 mg/g,游离烃含量平均高于3 mg/g,具备较好的页岩油勘探开发前景。

外源有机酸对复垦土壤中重金属Cr的活化效果研究

为了探究低分子有机酸(柠檬酸和苹果酸)对Cr污染土壤中Cr形态分布的影响,以淮南市潘一矿煤矸石山周边的复垦土壤为研究对象,通过模拟不同浓度Cr污染土壤,分析柠檬酸(CA)和苹果酸(MA)对土壤中Cr赋存形态的影响机制。结果表明:(1)随着外源Cr浓度的增加,土壤中Cr的活性有效提高。(2)柠檬酸和苹果酸的加入均可增加土壤中可交换态Cr的占比,即Cr的有效性得到提高,且随着柠檬酸和苹果酸浓度的升高,对土壤中Cr活化效果持续上升,柠檬酸的活化效果优于苹果酸。(3)随着老化时间的延长,有机酸对Cr的活化效果会减弱,弱结合态Cr将逐渐向强结合态Cr转化。因此,土壤重金属Cr污染修复中,可以考虑选用活化效果较好的柠檬酸作为修复辅助剂,来提升土壤Cr修复效率。研究结果可为矿区复垦土壤重金属Cr污染修复提供指导。

山东南吕—欣木金矿床金的赋存状态及富集机制

为探讨南吕—欣木金矿床金的赋存状态及富集机制,结合矿区地质特征,采用能谱和电子探针(EPMA)对研究区内采集的岩(矿)石标本进行分析,获取矿物生成顺序,分析金矿物的形态、粒度、成色和赋存状态,探讨金的富集机制。研究表明:南吕—欣木金矿床成矿阶段可划分为4个阶段,即黄铁矿—石英(Ⅰ)、金—石英—黄铁矿(Ⅱ)、金—石英—多金属硫化物(Ⅲ)和石英—方解石(Ⅳ),其中第Ⅰ、Ⅲ阶段是金的主要成矿阶段。金的赋存状态有晶隙金(占49.87%)、裂隙金(占42.81%)和包体金(占7.32%)。裂隙金的大小为7~20μm。金成色变化范围在886~943之间,平均成色为845,变化系数为11.72%。相关分析结果显示:相关性显著的元素是Ag和Ag、Fe和S。金与其他元素的相关性大小依次是Au→Ag→Cr→Fe→S,与Pb、Cu和Zn等元素相关性不大。黄铁矿是主要的载金矿物。金从矿源层(古老变质岩和玲珑复合岩体)溶滤出来,以简单的氯化物和络合物等迁移,富集在2个成矿阶段叠加部位。研究结果为揭示区域金的赋存状态和矿床成因提供了证据,也为总结焦家金成矿带成矿规律提供了科学依据。

长江中下游斑岩-矽卡岩铜多金属矿床共伴生碲、硒资源现状和成矿规律浅析

斑岩-矽卡岩铜多金属矿床常伴生大量的碲、硒资源,提供了全球目前几乎所有的碲、硒产量,但碲、硒在这些矿床中的成矿规律还不清楚。长江中下游成矿带多处铜多金属矿床都伴生有硒和/或碲资源,但其资源现状、赋存状态和成矿规律的研究还较为薄弱。本文基于已有的研究资料,对长江中下游伴生碲、硒资源量进行了估算,对碲、硒的赋存状态和分布规律以及成矿规律进行了探讨。目前长江中下游已探明的伴生碲、硒资源量分别为9061 t和10574 t,相当于18个大型碲矿床、21个大型硒矿床,这些矿产资源已部分回收利用。其中九瑞矿集区的资源量最大。碲、硒主要以独立矿物形式存在,发育4种产状碲的独立矿物和2种产状硒的独立矿物,它们均形成于硫化物阶段,后者主要形成于晚硫化物阶段。根据资源量相对规模,该成矿带上的矿床类型可分为硒矿床、碲硒和硒碲矿床三种。以岩体为中心向外,碲、硒含量由低到高依次为斑岩型矿体、矽卡岩型矿体和层间交代型矿体。本文初步揭示了长江中下游成矿带碲、硒矿化的成矿规律,可为资源评价和找矿勘查提供科学依据。今后应加强对斑岩-矽卡岩铜金成矿系统中碲、硒富集机制的研究。

某选厂硫尾矿工艺矿物学研究

为了提出尾矿资源化利用的合理利用方法,本文结合化学分析方法和矿物解离自动定量分析系统(MLA)针对某选厂的硫尾矿进行了工艺矿物学研究。化学分析结果表明,硫尾矿中SiO2、Al2O3和SO3含量分别为70.10%、11.85%和5.04%,高S影响了硫尾矿的直接利用。MLA分析表明,硫尾矿中主要矿物为石英、地开石、明矾石、黄铁矿和绢云母,S主要以硫酸盐和硫化物赋存于明矾石和黄铁矿中。粒度分析表明,硫尾矿-0.074 mm粒级占比48.69%,61.89%的SO3主要分布于该细粒级中;硫尾矿-0.01 mm粒级产率为16.21%,含泥量较高。矿物嵌布特征分析表明,硫尾矿中石英粒度相对较粗,明矾石和地开石具有在较细粒级富集趋势;硫酸盐矿物明矾石与石英、地开石、绢云母呈浸染状复杂连生,其在+0.043 mm粒级产品中解离度低于70%,总解离度为63.11%。为了脱出硫尾矿中的明矾石,需先脱泥脱硫后,细磨后再采用浮选进行分离。

安徽庐枞矿集区沙溪斑岩型铜金矿床中硒、碲的赋存状态及富集规律研究

硒和碲是重要的战略性关键金属,在现代工业和国防建设中有着广泛的应用。硒和碲通常很难形成独立矿床,目前全球大部分硒和碲来自斑岩型铜金矿床。长江中下游成矿带是我国东部重要的斑岩-矽卡岩型铜金矿床成矿带之一,前人虽然对成矿带内矽卡岩型矿床中伴生关键金属已开展了相关研究,但对成矿带内斑岩矿床中关键金属的赋存状态、分布和富集规律尚关注较少。本次工作以成矿带内沙溪斑岩型铜金矿床为研究对象,系统采集了矿床不同深度、不同类型的岩矿石样品,通过扫描电子显微镜、全岩化学分析、TIMA及矿物原位LA-ICP-MS微量成分测试等分析技术方法对矿床中硒和碲等关键金属开展了系统的研究。结果表明,沙溪矿床中硒和碲元素发生显著富集,与主成矿元素铜具有明显的正相关关系。估算矿床中伴生硒资源量约为1196t、碲资源量约为96.6t,其中硒达到大型规模,具有潜在利用价值。与成矿带内其他典型矽卡岩矿床(包括斑岩-矽卡岩矿床)相比,沙溪斑岩型矿床中硒和碲的含量明显偏低,这可能是深部成矿岩浆演化过程的差异导致的。矿床中有91.64%的硒、87.48%的碲是以独立矿物形式存在。沙溪矿床硒、碲与主成矿元素铜和金的富集规律一致,流体混合过程中氧逸度的变化可能是硒和碲的主要的沉淀机制。