Research Initiation: Micromixing Effects in Fast Aluminum Neutralization-Precipitation

研究启动：快速铝中和-沉淀中的微混合效应

• 批准号: 8808817
• 负责人: Mark Clark
• 金额: $ 7.8万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-06-01 至 1991-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8808817&HistoricalAwards=false
• 关键词: Research; Initiation; Micromixing; Effects; Fast

The objective of this project is to determine whether combining mathematical models of flow and small scale mixing with kinetic models for the neutralization-precipitation of aluminum in water treatment processes could predict the nature of the speciation of aluminum that occurs during fast-base neutralization in small, batch turbine reactors. While equilibrium chemical models have advanced the understanding of the chemistry of the aluminum system and its efficacy as a chemical coagulant for the treatment of potable waters, current approaches are unable to provide a prediction of the commonly observed effects of variable mixing and reactant injection techniques on final aluminum product distribution during treatment of drinking waters with aluminum coagulants. This project involves a study of the kinetics of aluminum product transformation in near-homogeneous base neutralization experiments (stopped-flow technique). Membrane filtration techniques and photon correlation spectroscopy will be used to monitor the formation of aluminum polymers and precipitate particles. The kinetic data will be incorporated in trial kinetic expressions and combined with specification for large and small scale mixing ("micromixing") of aluminum and base in turbulent reactors. The predictions of this mathematical model will be compared with experimental results for aluminum product speciation in larger scale aluminum neutralization studies with variable mixing and reactant injection techniques. Results of this work are likely to be applied toward improving the engineering design of water and wastewater treatment processes and systems.

本项目的目的是确定将流动和小规模混合的数学模型与水处理过程中铝的中和-沉淀动力学模型相结合，是否可以预测小型间歇式涡轮反应堆中快速碱中和过程中铝的形态的性质。虽然平衡化学模型促进了人们对铝体系化学及其作为化学混凝剂处理饮用水的有效性的理解，但目前的方法无法预测在使用铝混凝剂处理饮用水期间通常观察到的可变混合和反应物注入技术对最终铝产品分布的影响。本项目研究了铝产品在近均相碱中和实验(停流技术)中的转化动力学。膜过滤技术和光子相关光谱将用于监测铝聚合物和沉淀颗粒的形成。动力学数据将被合并到试验动力学表达式中，并与湍流反应器中铝和碱的大小规模混合(“微混合”)规范相结合。该数学模型的预测结果将与采用可变混合和反应物注入技术的大型铝中和研究中铝产品形态的实验结果进行比较。这项工作的结果可能应用于改进水和废水处理工艺和系统的工程设计。