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61.
�ӿ쿪�ɹ��ռ�����չ�ƶ����↑��������Ч 总被引:2,自引:0,他引:2
天然气开发生产是一个系统工程,各个环节必须服从天然气生产这个总的目标和总体效益增长。四川天然气生产有相当长的历史,积累了许多经验,但开采工艺却是整个系统工程中的薄弱环节。近年来,开采工艺面临的形势相当严峻:原有的开采系统不适应“东气西调”的格局;有水气田大部分进入开发中后期,工艺难度加大;储量增长中有相当一部分是低渗储量;含硫气田比例增加,腐蚀日趋严重。因而必须进一步解放思想,转变观念,坚持改革开 相似文献
62.
为了解决存在运动对象的场景中的背景恢复问题,采用了一种自适应的背景模型。这种背景模型结合背景的构建与更新为一体,不需要预先存储图像序列、它根据后续差异图像中提供的更新的背景信息,借助于背景颜色程度函数,跟踪记录图像中各象素出现的各种颜色的背景颜色程度变化从而得到最新的背景图像。实验表明这种方法对于背景中对象的运动和运动对象的逗留具有很强的适应能力,能以较快的速度恢复最新的背景图像。 相似文献
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基于排队论的车辆维修保障中维修组个数优化 总被引:2,自引:0,他引:2
利用排队论原理解决车辆维修保障中维修组个数的确定.首先在定点保障中,对维修组进行集中配置,由此确定定点维修中维修组数目.然后以车辆完好率为目标,确定伴随保障中抢修车的数量.最后,将运输任务重要程度对车辆战损率进行加权,确定应配置抢修车的车队的最小车辆数. 相似文献
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66.
阐述精馏工艺的控制要求及影响操作的因素。从产品质量,物料平衡,能量平衡。约束条件四方面控制角度出发,用于回收过程控制的应用,从而达到提高产品质量的目的。 相似文献
67.
In the present paper, influence of a lignin-based biopolymer in improving gold and silver recoveries during cyanidation leaching is discussed. Series of laboratory cyanidation leaching testworks at the absences and the presences of the biopolymer were performed under variations of the biopolymer concentration, NaCN concentration, slurry density and particle size distribution. The ore samples used were from Pongkor Gold Mine of PT. Antam, Tbk. in Indonesia. The biopolymer additive was found to reduce slurry viscosity that leads to a higher dissolved oxygen concentration in the leach solution. The testwork results show that the use of biopolymer improves gold and silver recoveries as well as leaching kinetics. At biopolymer dosage of 800 mg/L, the increases of gold and silver recoveries were 4.5% and 6.4%, respectively. The lignin-based biopolymer is able to disperse fine solid particles and stabilizes the ore suspension in the leach-slurry that results in a better contact between the ore and the leaching agents. The effect of biopolymer on the gold and silver recoveries was found to be more significant at lower cyanide dosages. The addition of biopolymer resulted in the increase of cyanide consumption, lowering final pH and higher dissolved iron which is associated with gold-bearing pyrite dissolution. Enhanced dissolution of gold-bearing pyrite at higher dissolved oxygen concentration was found as the major factor that improves gold recovery at the presences of the biopolymer in addition to lowering slurry viscosity that leads to higher dissolved oxygen concentration and effect of fine particles dispersion. 相似文献
68.
The effect of hydrophobic and magnetic plastic particles having a contact angle of around 83° on flotation performance was evaluated using coal particles of varying degrees of floatability. The magnetic plastic material were recovered by a low intensity magnetic separator and recycled back to the flotation feed for re-use. Flotation rate tests conducted on coal using a conventional cell proved that combustible recovery and flotation rate were significantly enhanced with the addition of the plastic particles, especially for difficult-to-float coals, which was corroborated by flotation column tests. Carrying capacity and particle size-by-size flotation tests further showed that the magnetic plastic particles preferentially increased the recovery of coarse particles by as much as 35 absolute percentage points due to froth stabilization which reduced the selective detachment of coarse and/or weakly hydrophobic particles. The enhanced flotation recovery was attributed to the influence on liquid drainage rate in the froth zone, froth stability, bubble coalescence and flotation rates. 相似文献
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70.
Rabih Murr Mahmoud Khaled Abdul Ghani Olabi 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(18):2207-2218
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