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991.
《矿业科学技术学报(英文版)》2019,29(2):313-317
Current use of enrichment and processing technologies of ores requires the introduction of closed circuits of water treatment. A decrease in technological properties is caused by accumulations of ion-molecular components in the circulating water. The objective of the simulation is to determine the maximum allowable concentrations of ions and molecules as well as the choice of conditions for deposition or adsorption. First of all, our examinations decrease the concentration of copper ions and fatty acids in the circulating water. By pre-mixing water with the highest concentration of these ions, a reduction of copper ion and fatty acid concentrations in the recycled water occurs. The results do not only ensure the achievement of the maximum permitted concentration (MPC) of copper and iron, significantly reducing the amount of oxidized copper, they also make it possible to use the united sewage as current water for the flotation process. Mixing and adding filtrate of tailings, discharges of urban wastewater treatment and effluent of ash pit of thermal power stations (TPS) to recycled water causes an increase in the capacity of the enrichment plant by 15–17%. 相似文献
992.
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994.
A laboratory scale rotary furnace has been developed for gaseous reduction of ultrafine metallurgical dusts to produce iron, zinc and other metal resources at submelting point temperatures. The kinetics of this process is much higher than say static or moving bed systems. By way of example, using dust with 38%Fe and 10%Zn, a 17?min treatment at 900°C produces an iron product of ~92%Fe and a zinc product of ~86%Zn. 相似文献
995.
It is estimated that Europe alone will need to add over 250,000 km of transmission capacity by 2050, if it is to meet renewable energy production goals while maintaining security of supply. Estimating the cost of new transmission infrastructure is difficult, but it is crucial to predict these costs as accurately as possible, given their importance to the energy transition. Transmission capacity expansion plans are often founded on optimistic projections of expansion costs. We present probabilistic predictive models of the cost of submarine power cables, which can be used by policymakers, industry, and academia to better approximate the true cost of transmission expansion plans. The models are both generalizable and well-specified for a variety of submarine applications, across a variety of regions. The best performing statistical learning model has slightly more predictive power than a simpler, linear econometric model. The specific decision context will determine whether the extra data gathering effort for the statistical learning model is worth the additional precision. A case study illustrates that incorporating the uncertainty associated with the cost prediction to calculate risk metrics - value-at-risk and conditional-value-at-risk - provides useful information to the decision-maker about cost variability and extremes. 相似文献
996.
Sibel Duman Bülent Kaya Fatma Caf Barış Enez Sema Aguloğlu Fincan 《International Journal of Hydrogen Energy》2021,46(29):15410-15430
For the first time in this innovative study, microorganisms such as Bacillus simplex bacteria, mostly used in biological activity studies, are used as a bio-supporter agent of iron to release hydrogen from sodium borohydride hydrolysis at 25.0 ± 0.1 °C. The goal is to investigate thoroughly sodium borohydride hydrolysis catalyzed by Fe2O3 nanoparticles impregnated on microorganism such as Bacillus simplex (BS) bacteria (Fe2O3@BS NPs) known with strong antibacterial properties, which makes innovative them a candidate for hydrolysis reaction. This study was focused on the preparation, identification, and catalytic use of biocatalyst-like Fe2O3@BS NPs for hydrogen release from the sodium borohydride hydrolysis at 25.0 ± 0.1 °C. The characterization results made after and before hydrolysis reaction using by SEM/SEM-EDX, FT-IR, XRD, UV–vis, XPS, DLS, ELS Zeta potential, ESR, and TEM techniques reveal the formation of highly active, stable, durable, and long-lived biocatalysts-like Fe2O3@BS NPs. 相似文献
997.
针对2002年铜地质勘查规范中一般工业指标存在的问题,基于大量实际生产数据,对铜矿床实际采用的边界品位指标、最低工业品位、矿床平均品位、最小可采厚度、夹石剔除厚度、开采技术条件等进行研究,论证了铜矿床的一般工业指标,并首次明确了铜矿床工业指标的适用条件,解决了铜矿床一般工业指标体系应用不一致和指标区间取值主观性的问题。 相似文献
998.
The Technology Readiness Level (TRL) scale is one of the most popular maturity assessment techniques used by industrial firms worldwide. However, it is not a panacea that will work for every firm or every industry in its original form. Consequently, for the scale to be truly useful, it has to be adapted to fit the unique features of different firms and industries. In this article, we propose a revised and domain-specific TRL scale for evaluating technology maturity in iron and steel industries. This revised scale takes into account the idiosyncrasies of such firms, for example, product/process interdependencies, scaling problems, the reliance on pilot and demonstration experiments, and the fact that input and output materials are ingredients rather than components. The revised TRL scale helps managers to assess technology maturity and reduce risk by delivering better project and technology evaluations and providing a ‘common language’. 相似文献
999.
湖北某难选金银矿选矿工艺流程试验研究 总被引:1,自引:0,他引:1
针对湖北某难选金银矿氧化率高,金、银嵌布粒度细微的性质特征,试验研究通过浮选、重选、浸出工艺等对比试验,最终确定采用全泥氰化的工艺流程回收矿石中的金、银,获得的选矿指标为:金、银的浸出率分别为68.32%、64.13%。该工艺的研究为合理开发此类金银矿提供了技术方向,同时提出了高氧化率金银矿的有效回收途径。 相似文献
1000.