Adapting membrane system operation and cleaning to varying raw water quality

根据不同的原水水质调整膜系统的运行和清洁

• 批准号: 485558-2015
• 负责人: Bérubé, Pierre
• 金额: $ 1.38万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=600141
• 关键词: Adapting; membrane; system; operation; cleaning

Membrane technologies are commonly used for water treatment applications throughout Canada and Internationally. The relatively rapid adoption of this novel technology over the past decade is largely due to its ability to produce high quality drinking water. During treatment, material that is retained at/in the membrane must be removed to prevent an excessive increase in the resistance to the permeating water. Hydraulic cleaning is typically used to remove most of the retained material (i.e. foulants). However, some of the foulants can only be removed chemically. Although effective at removing residual foulants, it is becoming increasingly evident that the use of chemical agents for membrane cleaning can negatively impact membrane performance. Over time, as a result of the impact of multiple chemical cleaning events, the membrane material is considered to have 'aged' beyond a trigger point and must be replaced. Coagulation-flocculation is commonly used prior to membrane filtration to improve the removal of contaminants in membrane systems, particularly components of dissolved organic matter that contribute to fouling. Because coagulation/flocculation affects the raw water matrix, it is also expected to impact the retention and accumulation of material by the membrane, and therefore chemical cleaning requirements as well as membrane ageing. Variations in source water quality are also expected to affect the performance of coagulation-flocculation and membrane systems and therefore chemical cleaning requirements. However, to-date, limited knowledge exists with respect to the effect of raw water quality and coagulation/flocculation practices on chemical cleaning requirements. The specific objectives of this study are to develop coagulation/flocculation protocols targeted specifically at the treatment of raw waters with highly variable characteristics, with the aim of identifying conditions that minimizing chemical cleaning requirements while maintaining water quality targets (concentration of organics, DBP precursor reduction).

膜技术通常用于加拿大和国际上的水处理应用。在过去十年中，这项新技术的相对快速采用主要是由于它能够生产高质量的饮用水。在处理过程中，必须去除保留在膜处/膜中的材料，以防止对渗透水的阻力过度增加。水力清洁通常用于去除大部分保留的材料（即污垢）。然而，一些污垢只能通过化学方法去除。虽然在去除残留污垢方面是有效的，但越来越明显的是，使用化学试剂进行膜清洁会对膜性能产生负面影响。随着时间的推移，由于多次化学清洁事件的影响，膜材料被认为已经“老化”超过触发点，必须更换。凝结-絮凝通常在膜过滤之前使用，以改善膜系统中污染物的去除，特别是有助于结垢的溶解有机物质的组分。由于凝聚/絮凝会影响原水基质，因此预计也会影响膜对材料的保留和积累，从而影响化学清洗要求以及膜老化。水源水质的变化预计也会影响凝聚-絮凝和膜系统的性能，从而影响化学清洗要求。然而，到目前为止，有限的知识存在的原水水质和混凝/絮凝的做法对化学清洗要求的影响。本研究的具体目标是开发专门针对具有高度可变特性的原水沃茨处理的混凝/絮凝协议，目的是确定在保持水质目标（有机物浓度，DBP前体减少）的同时最大限度地减少化学清洗要求的条件。