Advanced modelling for improved mixing of an Algal Biological Reactor (ABR) for sustainable water treatment within variable environments

新立法强调需要减少废水排放中的营养物质，如磷，以保护环境。水处理行业目前使用金属盐剂量（MSD）将磷沉淀成污泥，然后可以去除和处理。因此，对铁（最常用的MS）的需求大幅增加。目前的预测显示，到2025年，铁的供应将出现30%的短缺。此外，英国脱欧和COVID - 19的影响进一步加剧了供应链问题。因此，替代的非化学除磷方案是一个有吸引力的主张，并正在由英国水广泛试验。微藻是一种单细胞水生生物，它们可以利用光能从环境中吸收简单的营养物质以及二氧化碳。当在受控系统中使用时，微藻可用于去除废水中的污染物。藻类还可以去除其他有害物质，如重金属、化学物质和药物，有效地清洁水。通过支持Innovate UK的“A4I”竞赛，I-PHYC与世界领先的建模设施国家物理实验室和TÜV SÜD国家工程实验室合作。A4I，阶段1证明了CFD模型是可靠的，可以帮助决策以提高性能：*光谱和混合方法的调整显着增加了ABR内支持的生物量，而不会增加过程能耗。在装有5个浸没灯的同一反应器中，生物质产量增加了124%*通过增加垂直喷射臂（长管道，沿其长度有1mm孔，用于向水箱中注入空气以促进藻类混合的方法）获得了最高产量。然而，当安装在现实世界的废水处理厂时，沿混合臂的1mm孔很快被丝状细菌堵塞。盘式或管式扩散器用于“脏”废水应用-如混合污泥罐。这些系统使用先进的材料和防污涂层来减少污垢。一些膜被设计成在过程停止时放气，关闭孔洞。A4I的第二阶段将使用经过调整的模型来确定ABR在不同废水环境（固体和细菌负荷）中的理想位置和扩散器类型。一旦建立了稳健的模型，I-PHYC就可以做出明智的多层投资决策，从而使I-PHYC流程建立起具有竞争力、可持续的WW流程

New legislation has highlighted the need for nutrients, such as phosphorous, in wastewater (WW)discharges to be reduced to protect our environment. The water treatment industry currently usesmetal salt dosing (MSD) to precipitate the phosphorous into a sludge which can then be removedand disposed of. There has therefore been a massive increase in demand for ferric (the most used MS). Current forecasts predict there will be a 30% shortfall in supply of ferric by 2025\. In addition, supply chain issues are furtherexacerbated byeffects of Brexit and COVID 19\. Therefore, alternative nonchemical solutions for P removal are anattractive proposition and are being widely trialled byUK water.Microalgae are single-celled aquatic organisms that can use the energy from light to take up simple nutrients from their environment along with CO2\. When used in a controlled system, microalgae can be used to remove contaminants from WW. Algae can also remove other hazardous substances e.g. heavy metals, chemicals, and pharmaceuticals, effectively cleaning the water.Through the support of Innovate UK's 'A4I' competition I-PHYC collaborated with the National Physical Laboratory and TÜV SÜD National Engineering Laboratory, world leading modelling facilities. A4I, Stage 1 demonstrated that the CFD models are reliable and can help in decision making for improved performance:* Adaptations of light spectrum and mixing method significantly increased the biomass supported within the ABR without increasing process energy consumption. The biomass yield from the same reactor with 5 submerged lights increased by 124%* The highest yields were achieved with the addition of vertical sparging arms (long pipes with 1mm holes along their length, used here as a method of injecting air into the tank to promote mixing of the algae)However, when installed in real world wastewater treatment works the 1mm holes along the mixing arm quickly became blocked with filamentous bacteria.Disc or tube diffusers are used within 'dirty' wastewater applications -- such as mixing sludge tanks. These systems use advanced materials and antifouling coatings to reduce fouling. Some membranes have been designed to deflate when the process stops, closing the holes.Stage 2 of A4I will use the adapted models to determine the ideal locations and diffuser type for the ABR within variable wastewater environments (solids and bacterial loads).Once a robust model is created I-PHYC can then make informed multi-layered investment decisions, allowing the I-PHYC process to establish itself has a competitive, sustainable WW process