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61.
众所周知,矿物质的成分是多种多样的,社会的发展和科学的进步需要运用到多重金属矿物质,在专业人员的勘探与挖掘中,发现了黄沙坪铅锌多金属矿,这个矿区中有丰富的有色金属,这个矿的发掘为研究成矿规律提供了物质基础,同时也为深部找矿提供了可靠的依据。本文主要分析黄沙坪铅锌多金属矿的成矿规律及深部找矿远景。  相似文献   
62.
青海省格尔木市西大滩东多金属矿出露地层主要为早-中三叠世昌马河地层走向呈北西~南东向,与区域构造线方向基本一致。是测区的主要矿源层,为后期矿化提供了物质基础。比较发育的北西向、北西西向逆断层具有明显的多期活动特点,多形成破碎带,为热液活动、成矿元素富集提供了良好空间,对本区矿化起着一定的控制作用,破碎蚀变带控制了土壤异常展布。本文对西大滩东多金属矿控矿因素及找矿前景进行分析探讨。  相似文献   
63.
针对云南某铜矿嵌布粒度粗细不均、嵌布关系复杂、部分铜矿物易过磨损失,从而导致铜精矿中铜和伴生金、银回收率低的技术难点,通过采用铜选择性捕收剂BK901G和"铜快速浮选—中矿再磨再选"工艺流程,获得了较好的选矿指标,其中铜精矿中铜的品位和回收率分别达到23.79%和93.66%;伴生金、银的回收率分别达到43.92%和67.93%。该工艺技术可为同类型矿山提供借鉴。  相似文献   
64.
《Ceramics International》2020,46(7):8561-8566
ZrB2–SiC–graphite composites with 0–35 vol% graphite flakes were densified via hot-pressing route at the temperature of 1800 °C under the uniaxial pressure of 40 MPa for 1 h. Consolidation, mechanical properties, and microstructure of hot-pressed composites were investigated by variation of graphite content. By the addition of graphite, the relative density of composites increased, and at this hot pressing condition, fully densified composites were fabricated. The highest flexural strength of 366 MPa was measured for composite containing 7.5 vol% graphite, while the maximum Vickers hardness resulted in 2.5 vol% graphite doped one, and its value was equal to 20.8 GPa. Phase analysis of hot-pressed samples revealed the formation of the Zr3C2 and B4C phases besides the main existing ZrB2, SiC, and graphite phases. The newly carbide phases formed at the surface of ZrB2 grains. The addition of graphite into the ZrB2–SiC composites improved the sintering process and caused a fine-grained microstructure.  相似文献   
65.
《Ceramics International》2020,46(6):7888-7895
Graphite carbon nitride (g-C3N4) is an appealing metal-free photocatalyst for hydrogen evolution, but the potential has been limited by its poor visible-light absorption and unsatisfactory separation of photo-induced carriers. Herein, a facile one-pot strategy to fabricate carbon self-doped g-C3N4 composite through the calcination of dicyanamide and trace amounts of dimethylformamide is presented. The as-obtained carbon self-doped catalyst is investigated by X-ray photoelectron spectroscopy (XPS), confirming the substitution of carbon atoms in original sites of bridging nitrogen. We demonstrate that the as-prepared materials display remarkably improved visible-light absorption and optimized electronic structure under the premise of principally maintaining the tri-s-triazine based crystal framework and surface properties. Furthermore, the carbon doped g-C3N4 composite simultaneously weakens the transportation barrier of charge carriers, suppresses charge recombination and raises the separated efficiency of photoinduced holes and electrons on account of the extension of pi conjugated system. As a result, carbon self-doped g-C3N4 exhibits 4.3 times greater photocurrent density and 5.2 times higher hydrogen evolution rate compared with its bulk counterpart under visible light irradiation.  相似文献   
66.
The separation of iron oxide from banded hematite jasper(BHJ) assaying 47.8% Fe, 25.6% Si O2 and 2.30%Al2O3 using selective magnetic coating was studied. Characterization studies of the low grade ore indicate that besides hematite and goethite,jasper, a microcrystalline form of quartzite, is the major impurity associated with this ore. Beneficiation by conventional magnetic separation technique could yield a magnetic concentrate containing 60.8% Fe with 51% Fe recovery. In order to enhance the recovery of the iron oxide minerals, fine magnetite, colloidal magnetite and oleate colloidal magnetite were used as the coating material. When subjected to magnetic separation, the coated ore produces an iron concentrate containing 60.2% Fe with an enhanced recovery of56%. The AFM studies indicate that the coagulation of hematite particles with the oleate colloidal magnetite facilitates the higher recovery of iron particles from the low grade BHJ iron ore under appropriate conditions.  相似文献   
67.
An energy audit was conducted on a base metal milling facility where a top-down, bottom-up approach was presented to balance data measurements and estimates. The relation between throughput and specific electricity consumption, presented as a part-load efficiency curve for a milling operation, was established from the audit data. Unsurprisingly, the most efficient use of electricity occurred when the mill was operating at design capacity, but a survey of 14 metal mills operating in Ontario showed that 12 were operated under design capacity during 2012. For base metal flotation mills, 16–36% electricity cost savings could be realized by modification to the operating schedule, which would ensure that these facilities operated at design capacity even if plant operation was intermittent. With the Ontario electricity tariff arrangements, additional cost savings from strategic scheduling could reduce demand during coincident peak hours, which could provide financial benefit to these milling facilities.  相似文献   
68.
非洲某铜钴矿原矿含铜2.11%,钴0.090%,其中的钴品位较低,难以有效回收,且含钴矿物嵌布粒度不均匀,与黄铜矿、黄铁矿共生关系复杂,严重影响选矿过程中含钴矿物的综合回收。根据原矿性质,采用"铜钴依次优先"浮选工艺流程,结合使用高效选择性捕收剂BKAP,实现了铜、钴资源的综合回收,实验室所得铜精矿铜品位35.08%,铜回收率93.42%;钴精矿钴品位2.27%,钴回收率51.82%。  相似文献   
69.
新疆某硫化铅矿石中铅品位为13.35%、伴生银品位473g/t,铅主要赋存在方铅矿中,部分呈白铅矿、铅矾、磷氯铅矿形式存在。针对该矿石特点采用一次粗选、两次扫选、两次精选的闭路浮选试验,得到的铅精矿品位为铅66.12%、银1913g/t;铅精矿中铅、银回收率分别为:铅93.47%、银76.63%。试验结果可以为合理开发该矿石资源提供依据。  相似文献   
70.
吉尔吉斯斯坦某金多金属矿石中伴生多种有价元素,有用矿物嵌布状态复杂且嵌布粒度细。针对矿石性质,采用铜优先浮选—金钴混合浮选工艺流程,可初步实现该金多金属矿石中有价金属的有效分选。闭路试验可获得Au品位228.00 g/t、Au回收率12.19%,Ag品位974.00 g/t、Ag回收率37.71%,Cu品位27.590%、Cu回收率80.65%的铜精矿,以及Au品位65.00 g/t、Au回收率57.22%,Ag品位28.00 g/t、Ag回收率17.86%,Co品位0.5500%、Co回收率53.02%的金钴精矿。  相似文献   
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