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1.
目前我国绝大多数中小型老矿山残矿回收面临一系列问题,包括资料缺失无法准确判定老采空区及剩余资源位置,无法准确掌握剩余资源形态及可回收量,回收方案设计与实际资源相差较大等。通过将三维探测及建模技术应用于老矿山残矿资源精准定位及回收方案设计中,有助于解决以上问题。以福建浦城屏峰硫铅锌矿为例,通过对老采空区采用三维激光扫描构建采空区三维模型,结合三维建模计算,构建了目前可回收的剩余资源三维模型。通过模型划分及切割,按照矿体实际形态,在三维模型中布设采切及穿孔工程,并将其导入平面施工图中,不仅可以减少设计工作量,而且能够精准匹配矿体,减少设计偏差。由于周边存在大量老采空区,为保障安全,在采空区及剩余资源精准三维模型的基础上,制定了采空区稳定性监测方案,布设了监测传感器,保障了资源回收安全。  相似文献   
2.
杨懿 《石化技术》2020,(2):54-54,333
随着我国石油需求量不断增加,致密油藏的开发也愈发重要。如何高效开发致密油藏是一项重点难点,其中致密油藏注天然气提高采收率是一个极具潜力的研究方向。因此,本文着重介绍以天然气作为能量补充介质在国内外的研究现状和应用现状,并且从两相特征等方面总结了理论研究中的一些机理,对致密油藏注天然气提高采收率的发展前景进行了一定的展望。  相似文献   
3.
In this study the potential of cloud point extraction formed by a non-ionic surfactant was used in order to separate polyphenols from industrial residues of camu-camu. The effects of operational conditions of the cloud point extraction (CPE) on the polyphenol recovery and volumetric ratio were investigated. The results showed a maximum recovery of 95.71% that was obtained using 7.0 wt% Triton X-114, native pH (3.25), and 80 wt% polyphenol extract at 30 °C. The use of cloud point extraction was successful to recover the polyphenols from agroindustrial residue since it is a simple as well as of low-cost technique.  相似文献   
4.
为了更加准确地检测出图像中的显著性目标,提出了多先验融合的显著性目标检测算法。针对传统中心先验对偏离图像中心的显著性目标会出现检测失效的情况,提出在多颜色空间下求显著性目标的最小凸包交集来确定目标的大致位置,以凸包区域中心计算中心先验。同时通过融合策略将凸包区域中心先验、颜色对比先验和背景先验融合并集成到特征矩阵中。最后通过低秩矩阵恢复模型生成结果显著图。在公开数据集MSRA1000和ESSCD上的仿真实验结果表明,MPLRR能够得到清晰高亮的显著性目标视觉效果图,同时F,AUC,MAE等评价指标也比现有的许多方法有明显提升。  相似文献   
5.
针对国内某选矿厂铜浮选工艺泡沫速率不稳定,精矿品位波动大,回收率不理想等特点,设计了一套浮选专家控制系统,该系统结合泡沫影像分析技术,在线品位分析技术,PID控制与模糊逻辑控制技术。系统架构简明合理,逻辑层次清晰有效,投入运行一段时间后,在不同原矿品位前提下,都能实现稳定泡沫速率,减少精矿品位波动,提高回收率等指标优化,同时药剂添加量也有明显减少。这表明该系统运行效果良好,值得应用推广。  相似文献   
6.
针对四川某稀土矿选矿工艺存在的稀土回收率低的问题,开展了一系列选矿试验研究。试验结果表明,在矿浆质量浓度为30%,粗选NaOH用量为600g/t,水玻璃用量为3000g/t,EF1106用量为3500g/t,起泡剂用量为60g/t情况下,采用一粗、三精、两扫、中矿按顺序返回的选矿流程,可获得稀土REO的品位和回收率分别为66.32%和79.88%的稀土浮选精矿。与该选厂的生产指标相比,稀土回收率提高了13.93%。  相似文献   
7.
Proton induced X-ray emission (PIXE) technique and factor analysis were used to study the recovery of making-technology of Chinese Longquan celadon made in the late Southern Song Dynasty (1127–1279 CE). Based on factor analysis, for the raw material for body and the recipe for glaze, there is a close but slightly different relationship between these Longquan celadons unearthed from the core area of Dayao and the non-core area, despite all the Longquan celadons belong to the high-calcium-glaze system. The chemical compositions of most of the tentative body and glaze samples are very close to those of Longquan celadons unearthed from the core area of Dayao and the non-core area. This study can provide a guidance for recovery of making-technology of Longquan celandon.  相似文献   
8.
The race between the development of technologies and energy demand has drawn the guidelines of energy strategies for the next two decades. Indeed, the governmental organizations as well as the private sectors are spending huge effort to come up with new adequate strategies that allow to decrease energy consumption. Having said that, heat pump becomes an essential system in our daily life not only in residential building but also in hospital, industrial and touristic building. Nonetheless, (HP)s have very high energy consumption rate. Thus, and to be in line with the new trends in energy strategies, it is convenient to find new methods to enhance the performance of heat pump in order to reduce energy consumption. In this frame, the present paper suggests an approach to enhance the performance the heat pumps using the heat recovery from generators. For this purpose, an in-house code is developed allowing to simulate two new proposed systems (condenser upstream exhaust gases heat recovery system (CU-EGHRS) and condenser downstream exhaust gases heat recovery system (CD-EGHRS). It has been shown that the increase in the performance of the heat pump depends on the capacity of the generator. Also, the CD-EGHRS is shown to be the best. For instance, in the case of a 15 kVA generator, the enhancement could reach 42% for the CD-EGHRS. This enhancement increases to 5640% in the case of a 180 kVA generator.  相似文献   
9.
This study presents information obtained by the synthesis of Fe(3) oxide/hydroxide nanoparticles sol (NanoFe) and NanoFe-impregnated granular activated carbon as adsorbents for boron removal from solutions. The research describes an adsorption method for cleaning a solution containing boron contaminants followed by recovery of the adsorbent and the adsorbed material for safe removal or further reuse. The technology provides an efficient method of boron removal from water. A marked effect of NanoFe and NanoFe-impregnated GAC adsorbents concentration and pH level on boron removal efficiency was demonstrated. At least 95–98% boron recovery efficiency is possible using NanoFe sol and Fe-impregnated GAC that in fact also recover the adsorbent for reuse. Boron adsorption onto the NanoFe-impregnated GAC adsorbent may be described by pseudo-second-order reaction kinetics and the Langmuir isotherm model. The boron adsorption capacity on iron (3) oxide nanoparticles and Fe-impregnated GAC at an equilibrium concentration of 0.3 mg/dm3 as B in the solution is much higher than these values for similar adsorbents reported in the literature.  相似文献   
10.
Efficient gas recovery and separation in a hydrate-based system was investigated for a model gaseous mixture of R22 and nitrogen. The formed hydrate settled in the recovery vessel; excess water was recycled and the hydrate was subsequently decomposed by releasing pressure from the vessel. The gas uptake rate of R22 gas from the vapor phase and the gas recovery rate from the hydrate were determined from hydrate formation and decomposition, respectively. The gas recovery rate of R22 gas gradually increased with time. On the contrary, the nitrogen gas recovery rate was a maximum in the initial stage of hydrate decomposition. A high separation factor (S.F.) was achieved by first separating the N2-rich gas generated during initial hydrate decomposition. An efficient hydrate-based gas separation and recovery process is proposed.  相似文献   
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