SBIR Phase I: A Novel Photobiological Water Treatment Process for More Efficient Water Recovery in Advanced Water Reclamation and Brackish Groundwater Desalination Facilities

这个小企业创新研究第一阶段项目的更广泛的影响/商业潜力是影响美国及其他地区干旱和半干旱地区水资源短缺的潜力。 所提出的光生物水处理工艺利用光合微生物（硅藻）和阳光的自然力量，而不使用危险化学品或不可再生能源，以从来自先进的水回收和微咸水地下水淡化设施的浓缩废水流（盐水）中去除污染物，如二氧化硅、钙、铁、锰、磷和氮。 额外的清洁，（可再）使用的水可以从处理过的盐水中获得，非常具有成本效益，同时减少50%的盐水体积，并产生藻类生物质作为可销售的副产品。 这项技术将减少对环境的影响，并有可能提高水处理的效率。 这一第一阶段项目将对环境微生物学、水再利用和水资源管理方面的科学和技术进步产生更广泛的影响。 与淡水和海洋环境中发现的硅藻相比，本项目产生的实验数据可以揭示尚未详细研究的微咸水硅藻的许多特征和基本化学和生物学。 第一阶段研究项目的技术目标是研究基于生物降解的光生物工艺去除结垢和营养物的可行性，以从反渗透浓缩液中回收更多的淡水;表征该工艺的副产品，包括有机物和藻类生物量;并研究规模扩大的挑战。 挑战和机遇包括：（1）生物质生长和成分去除的优化，包括硅藻菌株筛选，（2）有毒元素、氯残留物、盐度、pH、温度、光源、强度和持续时间的影响，（3）副产物的形成和表征，（4）合成有机化合物如药物和个人护理产品的去除，（5）光生物反应器配置和水力学;（6）藻类生物质的可能用途和经济价值。 其中，主要的挑战是可能的可溶性有机副产物的形成和相对适度的二氧化硅吸收率。 将进行实验室和中试规模的实验，以优化光生物学过程，从而实现具有合理足迹的全面应用。 仔细的硅藻菌株/物种选择和更详细的化学和生物化学分析也将有助于进一步优化工艺，了解副产品的命运，它们对后续脱盐的影响以及可能的控制策略。

The broader impact/commercial potential of this Small Business Innovation Research Phase I project is the potential to impact water scarcity in arid and semi-arid geographies within the US and beyond. The proposed photobiological water treatment process utilizes the natural power of photosynthetic microorganisms (diatoms) and sunlight without the use of hazardous chemicals or non-renewable energy to remove contaminants such as silica, calcium, iron, manganese, phosphorus and nitrogen from the concentrated waste streams (brines) from advanced water reclamation and brackish groundwater desalination facilities. Additional clean, (re)usable water can be obtained from the treated brine quite cost-effectively, while reducing the volume of brine by 50% and producing algal biomass as a marketable by-product. This technology will reduce the environmental impact and also potentially improve the efficiency of water treatment. This Phase I project will have broader impacts on the advancement of science and technology related to environmental microbiology, water reuse and water resource management. The experimental data to be generated in this project could reveal many characteristics and fundamental chemistry and biology of brackish water diatoms that have not been studied in detail, as compared with those found in the freshwater and marine environment. The technical objectives in this Phase I research project are to investigate the feasibility of a diatom-based photobiological process for scalant and nutrient removal to recover more fresh water from reverse osmosis concentrate; to characterize the byproducts of this process including organic matter and algal biomass; and to investigate the scale-up challenges. The challenges and opportunities include: (1) the optimization of the biomass growth and constituent removal, including diatom strain screening, (2) impacts of toxic elements, chlorine residuals, salinity, pH, temperature, light sources, intensity, and duration, (3) formation and characterization of byproducts, (4) removal of synthetic organic compounds, such as pharmaceuticals and personal care products, (5) photobiological reactor configuration and hydraulics, and (6) possible uses and economic values of algal biomass. Among them, the major challenges are the possible soluble organic byproduct formation and the relatively modest silica uptake rate. Bench- and pilot-scale experiments will be conducted to optimize the photobiological process to enable a full-scale application with a reasonable footprint. Careful diatom strain/species selection and more detailed chemical and biochemical analyses will also facilitate further process optimization and understanding of the fate of byproducts, their impacts on subsequent desalination, and possible control strategies.