Effects of foam fractionation and chemical disinfection on the removal of different microalgae cultures

Ozone application in different industries: A review of recent developments

“…Additionally, ozone has been used to reduce organic matter in RAQS, by promoting flocculation of organic matter [73] ; thus reducing the total suspended solids (TSS), chemical oxygen demand (COD) and dissolved organic carbon (DOC); the load on the biofilters and oxygenators is also reduced via ozonation [105] . The application of ozone for shellfish depuration [107] , removal of algal toxins [108] , the improvement of fish taste and odour [109] , and water colour elimination [110] have also been reported. More importantly, the overall enhancement of the water quality via disinfection against bacteria and viruses (including Aeromonas hydrophilia [111] , Vibrio parahaemolyticus [73] and Motile Aeromonas septicaemia [112] ) is well documented.…”

Removal of microparticles and bacterial inactivation in freshwater RAS by use of foam fractionation, H 2 O 2 and NaCl

“…Direct and indirect impacts of these particles on fish performance and RAS operation have recently been described (Becke et al, 2020;. Recent aquaculture studies have demonstrated methods to control and remove the waterborne bacterial load by removing microparticles or inactivating bacteria (Bentzon-Tilia et al, 2016;Fossmark et al, 2020;Huyben et al, 2018;de Jesus Gregersen et al, 2020;Wold et al, 2014). However, there is still a need to test and develop alternative, simple and cost-effective water treatment methods that can improve water quality in RAS.…”

“…The limited or absent use of FF in freshwater is primarily associated with a suboptimal removal efficiency due to larger bubble sizes and less surface tension compared to seawater. Recent studies have shown that ozone can improve FF treatment efficacy in seawater (Figueiras Guilherme et al, 2020; Park et al, 2015), although using ozone is challenging due to its toxicity and safety issues for fish and staff (Bregnballe, 2015). Hydrogen peroxide (H 2 O 2 ) is a milder alternative to ozone with similar characteristics (i) can be used to oxidize organic matter (Cuerda‐Correa et al, 2020) (ii) is easily degradable, (iii) do not form harmful by‐products (Schmidt et al, 2006) and (iv) is commonly applied in aquaculture systems (Arndt & Wagner, 1997; Bögner et al, 2020; Pedersen & Pedersen, 2012; Rach et al, 1998; Saez & Bowser, 2001).…”

A Bioflocculant Made from Chitosan and Modified Shrimp Waste Might Collect Fresh and Saltwater Microalgae

“…Since microalgae have certain features, it is essential to choose the best flocculation technique for harvesting them. Several methods are adopted for the efficient harvesting of microalgae 7 , centrifugation 9 , foam fractionation 10 , filtration 11 , flocculation 12 and gravity sedimentation 13 . Even more energy-intensive and costly than modern cell harvesting techniques like centrifugation and filtering 14 .…”