Multi-Species Slurry Pipeline Transportation

多品种浆体管道输送

• 批准号: 0085645
• 负责人: M. Ebadian
• 金额: --
• 依托单位: Florida International University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-10-01 至 2001-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0085645&HistoricalAwards=false
• 关键词: Multi; Species; Slurry; Pipeline; Transportation

Pipeline systems are widely used in transportation industries. Examples are transportation of coal, iron ore, mineral concentrates, ore tailings, sewage sludge, and nuclear waste. In many of these applications, transported slurries are complex multi-species mixtures. In the past, most of the theoretical and experimental studies dealt with only single-component slurries such as sand- or coal-water mixtures; little is known about multi-species slurries. The design of pipeline systems based on the studies of single-component slurries causes substantial limitation of safety and efficiency. Thus, there is a significant need to study multi-species slurry transportation in order to build a scientific basis for better pipeline system design in the future. It is proposed to study multi-species slurry transportation both experimentally in the lab-scale flow loop and numerically, using commercially available solvers as well as developing new computer codes. Both two- and three-component slurries will be used in the study to focus research on the effects of slurry component density on transport characteristics. Materials such as glass particles, sand, aluminum oxide, and nickel oxide will comprise slurry components in studying density ratios of heavier to lighter material in the range of 1.2 to 5.0. Different particle sizes of slurry components in the range of 50m to 500m and different relative component concentrations in the slurry will be tested. In addition, we will study solids concentrations in the range of 5% to 40% by volume for each slurry recipe. A flow loop for slurry transport experiments will be constructed. The flow loop and its instrumentation will be calibrated by performing experiments with clear water. Next, slurry transport experiments in the flow loop will be performed. Important engineering parameters such as critical deposition velocity and pressure drop versus flow velocity will be of interest. Flow patterns associated with different flow regimes will be examined by using flow visualization techniques such as Particle Image Velocimetry (PIV). A wide range of Reynolds numbers from 500 to 100000 will be considered to cover laminar, transitional, and turbulent flow regimes. Critical deposition velocity will be determined by visual observations of particle settling and from the turn point on the pressure drop versus mean flow velocity curve. Rheology studies of slurries under investigation will be performed. A reasonable numerical model of multi-species slurry flow will be developed. Experimental data will be used to improve numerical model. Improved model will then be used for parametric study to obtain detailed information about the effects of solids densities, particle sizes, and solids concentrations on slurry transport characteristics. In addition, we will study re-suspension phenomenon to investigate pipeline restart feasibility and characteristics. Slurry will be allowed to fully settle in the loop and then mean slurry velocity will be increased gradually until the settled bed is completely removed.Correlations and numerical models obtained from this research will be useful in designing next-generation pipeline systems for multi-species slurry transportation. The study will also contribute to the improved fundamental understanding of physical phenomena associated with multi-phase flows.This award is made under the Exploratory Research on Engineering the Transport Industries (ETI) program solicitation.

管道系统广泛应用于运输行业。例如煤炭、铁矿石、矿物精矿、尾矿、污水污泥和核废料的运输。在许多这些应用中，输送的浆料是复杂的多组分混合物。过去，大多数理论和实验研究只涉及单组分浆料，如砂或煤水混合物；人们对多物种浆液知之甚少。基于单组分浆料的管道系统设计在安全性和效率方面存在很大的局限性。因此，有必要对多品种浆液输送进行研究，为今后更好地设计管道系统奠定科学依据。建议利用商业上可用的求解器和开发新的计算机代码，在实验室规模的流环中实验和数值上研究多物种浆体输运。本研究将采用双组份和三组份浆体，重点研究浆体组份密度对输运特性的影响。在研究较重和较轻材料的密度比在1.2到5.0范围内时，玻璃颗粒、沙子、氧化铝和氧化镍等材料将包含浆料成分。测试50m ~ 500m范围内不同粒径的料浆组分，以及料浆中不同相对组分浓度。此外，我们将研究固体浓度范围在5%至40%的体积为每个浆料配方。将构建一个用于浆体输运实验的流环。流动回路及其仪器将通过用清水进行实验来校准。接下来，将进行流环内浆体输运实验。重要的工程参数，如临界沉积速度和压降相对于流速将是感兴趣的。与不同流动状态相关的流动模式将通过使用流动可视化技术，如粒子图像测速（PIV）进行检查。将考虑从500到100000的广泛雷诺数范围，以涵盖层流，过渡和湍流流型。临界沉积速度将通过颗粒沉降的目视观察和压降与平均流速曲线的转折点来确定。将对所调查的浆料进行流变学研究。建立合理的多组分浆体流动数值模型。实验数据将用于改进数值模型。改进后的模型将用于参数化研究，以获得固体密度、颗粒大小和固体浓度对浆体输运特性影响的详细信息。此外，我们将研究再悬浮现象，以探讨管道重启的可行性和特点。泥浆将被允许在循环中完全沉降，然后平均泥浆速度将逐渐增加，直到沉降床被完全移除。本研究所获得的相关关系和数值模型将有助于设计下一代多品种浆体输送管道系统。该研究也将有助于提高对与多相流相关的物理现象的基本理解。该合同是在运输工业工程探索性研究（ETI）项目招标下获得的。