Advanced modelling for improved separation efficacy from Industrial Phycology’s algal wastewater treatment process – Reducing the CAPEX and OPEX of sustainable water treatment process

New legislation has highlighted the need for nutrients, such as phosphorous and ammonium in wastewater (WW) discharges to be reduced to protect our environment. The water treatment industry is currently heavily dependent on the use of chemicals to promote phosphate-precipitation into a sludge which must then be removed and disposed of. There has been a massive increase in demand for ferric (the most used common chemical option). Current forecasts predict there will be a 30% shortfall in supply of ferric by 2025\. Therefore, alternative nonchemical solutions for nutrient removal is of significant interest within the WW sector.

Industrial-Phycology (I-Phyc) has developed a process based on the industrial application of microalgae for the sustainable and environmentally friendly treatment of WW. The I-Phyc process utilises the algal cell as a biocatalyst, which ensures fast and effect removal of phosphate, ammonium, and a wide range of emerging containments simultaneously. The I-Phyc process has been designed to be retrofitted onto small WW treatment works, removing the need chemicals.

The use of the algal biomass and the quality of the treated water are critical to the process and are both dependent on the technology used to separate the algae from the water. However, this is known to be challenging due to the low biomass to liquid ratio, small cell sizes, and specific gravities very similar to that of the medium, creating a stable suspension. I-Phyc currently employs the best-known technology, centrifugation, to separate the algal material, however the technology is prohibitively expensive and represents ~30% of the total energy required for the whole I-Phyc process. It also requires significant and complex maintenance. Water operators are well known to be risk averse, therefore the separation technology selected must meet I-PHYC's requirements and be relatively well known in the water industry.

I-Phyc has been screening several separation technologies, however each of technology has multiple variables that can be altered to affect the efficiency of separation making optimisation time consuming. Through the support of Innovate UK's 'A4I' competition I-Phyc will collaborate with TÜV SÜD National Engineering Laboratory (NEL) a world leading modelling facility. I-Phyc has previously worked with NEL and understands the impact modelling can have on the depth and speed of decision making. Working with leading experts to model and optimise the separation technologies would significantly reduce I-Phyc's capital and operational costs and increase the number of potential wastewater sites, which often have limited electrical capacity