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51.
Over 378,000 m3 (100 million gal) of radioactive waste is being stored in hundreds of tanks at several U.S. Department of Energy (DOE) sites. The environment within the tanks is highly radioactive and chemically harsh. The waste typically consists of a heterogeneous sludge layer covered by a layer of supernatant. A few of the tanks have leaked to the environment, while others are corroding. Removing the waste from the tanks and processing it to a stable final form are desired to prevent any additional contamination of the environment. The tanks vary in size and geometric shape and do not have systems for removing the sludge waste.
Mobilization and mixing studies were conducted with a surrogate sludge (e.g., kaolin clay) using submerged jets in two sizes of horizontal tanks with nominal capacities of 0.87 m3 (230 gal) and 95 m3 (25,000 gal). Mobilization efficiencies and mixing times were determined for single and bidirectional jets in both tanks with the discharge nozzles positioned at various locations in the tanks. Approximately 80% of the surrogate sludge was mobilized in the 95-m3 tank using a fixed bidirectional jet (inside diameter = 0.035 m) and a jet velocity of 6.4m/s (21 ft/s). The effective cleaning length, which is defined as the distance between the jet and the edge of the remaining sludge bank, was approximately 3.2 m (10 ft) on each side of the bidirectional jet. 相似文献
Mobilization and mixing studies were conducted with a surrogate sludge (e.g., kaolin clay) using submerged jets in two sizes of horizontal tanks with nominal capacities of 0.87 m3 (230 gal) and 95 m3 (25,000 gal). Mobilization efficiencies and mixing times were determined for single and bidirectional jets in both tanks with the discharge nozzles positioned at various locations in the tanks. Approximately 80% of the surrogate sludge was mobilized in the 95-m3 tank using a fixed bidirectional jet (inside diameter = 0.035 m) and a jet velocity of 6.4m/s (21 ft/s). The effective cleaning length, which is defined as the distance between the jet and the edge of the remaining sludge bank, was approximately 3.2 m (10 ft) on each side of the bidirectional jet. 相似文献
52.
53.
介绍了基于PLC的压缩机一体化控制系统,PLC和现场总线系统(DCS)、安全仪表系统(SIS)、马达一体化控制系统(MCC)等信号之间的相互关系。主要论述了压缩机的防喘振控制理论,防喘振控制器的功能及防喘振控制在赛科乙烯装置裂解气压缩机的应用。 相似文献
54.
基于VOF模型,运用三种不同的造波方法建立了二维数值波浪水槽,并对其进行了比较,选取了在特定波况下较为合适的数值水槽。基于该数值波浪水槽,考察了波浪作用下的运动状态以及受力状态,为波能转换器的设计提供指导。 相似文献
55.
坦克装甲车辆用橡胶履带板的研究开发 总被引:1,自引:0,他引:1
探讨了坦克装甲车辆用橡胶履带板(TTRP)的损坏摸式及其机理,从胶料配合,性能测试等方面评 TTRP的研究开发进展,并对我国TTRP的研究提出了建议。 相似文献
56.
The adsorption of cobalt phthalocyanine dye onto activated carbon in a continuous stirred tank adsorber was studied. The variables investigated were: adsorbent mass, adsorbent particle size and fluid flowrate. Several models based on film, pore and surface diffusion were constructed and fitted to the experimental data. Experimental results showed: (i) the increasing importance of the film mass transfer resistance for increasing adsorbent loads; (ii) the increasing importance of the surface diffusion mechanism for increasing adsorbent loads; and (iii) the better discrimination among different models for higher adsorbent loads and lower flowrate. 相似文献
57.
The aim of this study is to optimize the position and the number of propellers in a non-standard tall vessel. Laser sheet flow visualization experiments were carried out for selected geometrical arrangements which produced stable flow patterns and good transport between the propellers. Four double-propeller arrangements corresponding to frequent industrial cases and a three-propeller system have been chosen. Comparison of LDA measurements in the r-z plane, dimensionless global parameters NQp, Ntm, Np, Ep and spatial distribution of local energy dissipation rate ? shows that a three-propeller system is the most efficient. 相似文献
58.
液氨贮存设计分析 总被引:3,自引:0,他引:3
马朝玲 《硫磷设计与粉体工程》2004,(1):20-22
氨是生产含氮肥料及尿素的基本原料,为确保原料供应,必须设置其贮存设施。介绍了常温中压、降温低压和低温常压三种不同的液氨贮存工艺及其特点,并以某大型氨站设计为例,分析了液氨贮存工艺流程、主要设备、材料的选型和工艺参数的确定。 相似文献
59.
本文针对中压汽包法兰断裂失效原因进行分析,指出汽包上两个法兰同时断裂的原因在于安全阀排汽管路设计上的失误,并提出对安全阀排汽系统的改进措施。 相似文献
60.
叙述了用多晶氧化铝纤维和高铝纤维制成的混合纤维段制品的生产工艺。该制品是一种能在1350℃长期使用的隔热新材料,它用在全电加热玻璃窑供料道后,玻璃液温度稳定,料滴温度长期控制精度可达±1℃,成品率上升到96.6%,能耗降低。 相似文献