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81.
针对郴州某复杂硫化铅锌矿资源的性质特点,采用铅快速浮选后尾矿再磨再选的阶磨阶选工艺,较好地实现了铅锌的高效浮选回收。研究了磨矿方式、捕收剂和调整剂种类及用量等因素对该矿石浮选的影响,确定了最佳浮选条件,通过小型闭路浮选试验,得到了铅品位60.05%、回收率89.63%的铅精矿和锌品位47.01%、回收率88.14%的锌精矿。 相似文献
82.
为了验证在某复杂难选铁矿石的选矿工艺中,应用高压辊磨机和立式搅拌磨的优越性,进行了一系列对比试验。结果表明,与颚式破碎机相比,高压辊磨机产品的粉矿率更高,产品的可磨性更好;与球磨机相比,立式搅拌磨机细磨效率更高、效果更好,相同磨矿细度下,立式搅拌磨机磨矿产品的解离度更高,磁选铁精矿品位也更高;高压辊磨+立式搅拌磨在处理复杂难选铁矿石方面具有显著的优势。 相似文献
83.
84.
The surface chemistry and mineral liberation changes of a porphyry copper ore after high voltage pulse (HVP) electrical comminution have been investigated using X-ray photoelectron spectroscopy (XPS) and mineral liberation analysis (MLA). Previous studies suggest that electrical comminution has the potential to improve downstream flotation recoveries, due to increased mineral liberation. However, until now the effects on the surface chemistry have not been investigated in detail.The mineral liberation results showed that chalcopyrite was more liberated in the electrical comminution product than in mechanical comminution, noticeably in the coarser size fractions. The surface chemistry of pure chalcopyrite was investigated, using XPS, and high resolution scans of iron and sulphur showed that both comminution methods led to iron oxidising preferentially leaving behind a passivating film of copper sulphides. However, the HVP product oxidisation was more severe with more iron oxide being produced and further oxidation of the remaining copper sulphides into copper sulphate. An attrition grinding stage may be useful in removing the oxidised layer from the surface of the particles prior to flotation separation. This paper presents a new application of the HVP technology in hybrid procedures using electrical comminution and mechanical grinding to prepare the flotation feed, rather than using excessive pulse energy to fully disintegrate ore to the flotation size. Better liberation and flotation performance were achieved through the hybrid procedures than the comparative mechanical comminution. 相似文献
85.
《Microelectronics Journal》2015,46(11):1012-1019
This paper presents a voltage reference generator architecture and two different realizations of it that have been fabricated within a standard 0.18 μm CMOS technology. The architecture takes the advantage of utilizing a sampled-data amplifier (SDA) to optimize the power consumption. The circuits achieve output voltages on the order of 190 mV with temperature coefficients of 43 ppm/°C and 52.5 ppm/°C over the temperature range of 0 to 120°C without any trimming with a 0.8 V single supply. The power consumptions of the circuits are less then 500 nW while occupying an area of 0.2 mm2 and 0.08 mm2, respectively. 相似文献
86.
The paper aimed to maximize the fuel burnup performance of plutonium and minor actinides fueled pebble bed high temperature reactor (PBMR-400). The PBMR-400 was designed as a reference core. The neutronic calculations were performed by the code combination MCNP-ORIGEN-MONTEBURNS. In this study, neutronic performances of three different types of nuclear fuels (Reactor Grade Plutonium – RGPu; Weapon Grade Plutonium – WGPu and Minor Actinides – MAs) combined with natural uranium were conducted in a PBMR-400 full core. The neutronic performances were compared with the original uranium fuel designed for this reactor. Neutronic calculations showed that 9.6 wt % enriched uranium has a core effective multiplication factor (keff) of 1.2395. Corresponding to this keff values the natural UO2/RG-PuO2; natural UO2/WG-PuO2 and natural UO2/MAO2 mixture were found 70%/30%, 76%/24% and 63%/37%, respectively. The operation times were computed as ∼2000, ∼2500 and 1400 days whereas, the corresponding burnup values were obtained as ∼163 000, ∼194 000 and ∼116 000 MWD/T, respectively, for end of life keff set equal to 1.08. 相似文献
87.
88.
低压配电系统对建筑电气工程是非常重要的,本文对其安装做论述,针对各种建筑物对配电的要求,对系统做合理的调试,最终实现建筑实体安全用电,同时也确保低压配电系统的稳定性。 相似文献
89.
王小生 《有色金属(选矿部分)》2019,(1):35-38
柿竹园野鸡尾铜锡多金属矿含Cu 0. 18%,含Sn 0. 36%,其它有价元素均较低。由于铜锡有价元素嵌布粒度较细,磨矿粒度较细,采用重选回收率较低,因此采用浮选的方法来回收锡石。本研究采用碳酸钠作为pH值调整剂,硝酸铅作为活化剂,GYB作为捕收剂,松醇油作为起泡剂,采用一次粗选两次扫选三次精选的工艺流程,最终闭路试验结果表明,锡石精矿中锡含量为5. 27%、回收率62. 42%。 相似文献
90.