Sequencing batch membrane photobioreactor for simultaneous cultivation of aquaculture feed and polishing of real secondary effluent

Continuous 3-year outdoor operation of a flat-panel membrane photobioreactor to treat effluent from an anaerobic membrane bioreactor

“…However, their direct discharge into sensitive water bodies is not permitted, since these systems contain a large amount of nutrients (Song et al, 2018) which can lead to eutrophication, i.e. the sudden proliferation of algae in natural waters, which reduces water quality, increases health risks and impairs wildlife (Lau et al, 2019). Microalgae cultivation has emerged as the ideal option to avoid this problem, as it can recover nutrients from AnMBR effluents (González-Camejo et al, 2019a).…”

“…In addition, COD is usually directly related to microalgae biomass(Ambat et al (2018)). sCOD concentration was also expected to show higher influence on MPBR performance as it can be used as an indirect measure of extracellular organic matter (EOM) content.However, the results of the fitted PLS model gave little weight to these variables(Figure 6b), possibly due to the production of these organic compounds being increased either to microalgae activity(Lau et al, 2019), or when algae are under stress(Lee et al, 2018). In addition, the proliferation of competing organisms such as heterotrophs (which hinder microalgae activity) reduces the sCOD in the culture(Galès et al, 2019).The variance in this parameter could thus be influenced by both high and low microalgae and heterotrophic bacteria activity and their correlation pattern could have changed throughout the 3-year operating period, reducing their importance in the overall model.…”

Emerging trends of culturing microalgae for fish‐rearing environment protection

“…Although the replacement of traditional fish diet by living algal cells is considered a promising pathway to eco-friendly aquaculture, the high production cost of microalgae biomass hinders its commercial application. The study by Lau et al (2019), growing microalgae in wastewater to produce biomass as fish diet, estimated that the biomass production costs are 11.1-15.1 USD/kg. 17 Sui et al (2020) reported that the production cost of protein-rich microalgal biomass could reach 11 GBP/kg and the profitable minimum selling price should be 14.4 GBP/kg.…”

“…The study by Lau et al (2019), growing microalgae in wastewater to produce biomass as fish diet, estimated that the biomass production costs are 11.1-15.1 USD/kg. 17 Sui et al (2020) reported that the production cost of protein-rich microalgal biomass could reach 11 GBP/kg and the profitable minimum selling price should be 14.4 GBP/kg. 1 Compared with the current market price of fishmeal (1.7 USD/kg), the microalgae do not show any cost advantages for the commercial application in aquaculture.…”

“…1 Compared with the current market price of fishmeal (1.7 USD/kg), the microalgae do not show any cost advantages for the commercial application in aquaculture. 17 Since the harvesting cost accounts for 20-30% of the total cost of biomass production, a lot of effort has been devoted to the reduction of the harvesting cost. Recently, Gross and Wen (2014) designed a revolving algal biofilm (RAB) system that simplified the biomass harvesting process and cost by growing microalgae on the surface of a supporting material and harvesting the biomass using scraper.…”