CAREER: Impacts of Marine Algal Blooms on Disinfection Byproduct Formation in Seawater Desalination

题目：职业：海水淡化中藻华对消毒副产物形成的影响名称：Ning Dai提案号：1652412基于反渗透（RO）的海水淡化是满足日益增长的全球用水需求的最重要技术之一。在反渗透海水淡化厂的进水处，通常添加消毒剂（例如氯）以抑制微生物对处理单元，特别是反渗透膜的污染。这些消毒剂可与海洋有机物反应形成有害的消毒副产物（DBPs）。最近，由于藻华期间高浓度的藻有机物（AOM），海洋藻华被证明会导致严重的膜污染，从而中断海水淡化作业。虽然消毒剂对控制藻华期间的污染至关重要，但高AOM浓度对淡化过程中DBP形成的影响尚未得到考虑。在这个项目中，PI将调查与海洋藻华有关的藻类物种形成DBP，并将为海水淡化作业制定减缓DBP的战略。教育活动将侧重于提高所有学位水平的环境工程专业学生的专业能力，并扩大未被充分代表的群体在科学、技术、工程和数学（STEM）领域的参与。该项目将侧重于海洋藻类形成DBP的基本原理以及将研究结果应用于海水淡化作业。该项目将包括四个研究目标。首先，在模拟藻华期间海水淡化消毒的条件下，评估与藻华相关的海洋藻类物种的DBP形成潜力。有代表性的物种将根据它们与美国海岸海藻繁殖的相关性来选择。藻类培养物和提取的细胞内和细胞外AOM将受到一系列消毒剂、氯、氯胺、二氧化氯、臭氧、高锰酸盐及其组合的影响。其次，将评估来自不同藻类生长阶段的新鲜AOM和经过生物和非生物转化的老化AOM的DBP形成。第三，确定海藻细胞形成DBP的机制和重要的DBP前体。海水淡化情景下DBP形成的基本知识将是设计海水淡化设施DBP预防策略的基础。最后，研究AOM转化对消毒过程中膜污染电位的影响，提出在膜污染控制和DBP预防之间取得平衡的策略。分析工具，如气体、液体、尺寸排除色谱、质谱和分光光度法将被用于监测DBP的形成和表征AOM的转化。整体教育活动将包括研究生研究培训和指导，为本科生提供研究经验，在研究生和本科生环境工程课程中纳入基于合作设计项目的学习，以及以高中和初中教师发展为重点的K-12外展。

Title: CAREER: Impacts of Marine Algal Blooms on Disinfection By-Product Formation in Seawater DesalinationPI Name: Ning Dai Proposal Number: 1652412 Reverse osmosis (RO)-based seawater desalination is one of the most important technologies for meeting the growing global water demand. At the intake of RO desalination plants, disinfectants (e.g., chlorine) are often added to suppress fouling of the treatment units, especially RO membranes, by microorganisms. These disinfectants can react with marine organic matter to form harmful disinfection by-products (DBPs). Recently, marine algal blooms were shown to interrupt desalination operations by causing severe membrane fouling, as a result of the high concentration of algal organic matter (AOM) during algal blooms. While disinfectants are crucial for controlling fouling during algal blooms, the implications of high AOM concentrations on DBP formation in desalination have not been considered. In this project the PI will investigate the formation of DBPs from algae species relevant to marine algal blooms and will develop DBP mitigation strategies for desalination operations. Education activities will focus on promoting professional competencies of environmental engineering students at all degree levels and on broadening participation of underrepresented groups in science, technology, engineering, and mathematics (STEM). This project will focus on both the fundamentals of DBP formation from marine algae and the application of findings to desalination operations. The project will encompass four research objectives. First, the DBP formation potential of bloom-relevant marine algae species will be evaluated under conditions simulating disinfection in seawater desalination during algal blooms. Representative species will be selected based on their relevance to marine algal blooms along the US coasts. The algae culture and the extracted intra- and extra-cellular AOM will be subjected to a suite of disinfectants, chlorine, chloramine, chlorine dioxide, ozone, permanganate, and their combinations. Second, DBP formation will be evaluated for fresh AOM derived from different algae growth stages and aged AOM after biotic and abiotic transformation. Third, the mechanisms of DBP formation from marine algae cells and the important DBP precursors will be identified. The fundamental knowledge of DBP formation under desalination scenario will be the basis for designing DBP prevention strategies for desalination facilities. Lastly, the effects of AOM transformation upon disinfection on its membrane fouling potential will be characterized to suggest strategies to achieve a balance between membrane fouling control and DBP prevention. Analytical tools such as gas, liquid, and size exclusion chromatography, mass spectrometry, and spectrophotometry will be employed to monitor DBP formation and characterize AOM transformation. The integral educational activities will include graduate student training in research and mentoring, providing research experience for undergraduates, incorporating cooperative design project-based learning in graduate and undergraduate environmental engineering courses, and K-12 outreach focusing on high school and middle school teacher development.