Ultrasonic sound treatment of process water in aquaculture- and wastewater treatment facilities

Within the UvPAA- project the use of high frequent ultrasound for disinfection of process water from Recirculating Aquaculture Systems (RAS) and wastewater plants will be studied. This include the physicochemical and microbiological analysis of the process water before and after ultrasound treatment in order to detect any reduction of dissolved organic substances and bacterial load, changes in the bacterial community composition as well as changes in the main parameters required for the correct maintenance of the reared species and the biofilters of the RAS.

The goals of the project are to develop and construct a prototype, to test it under real commercial conditions, and to describe the method under standardized and controlled settings in a RAS under different input features of the effluent to be cleaned. Using molecular biological methods for microbial identification and quantification such as FISH/CARD-FISH and qPCR, will allow to monitor the success of the disinfection process and to assess the taxonomic composition of the microbial community under diverse environmental conditions according to the treatment intensity and exposure period. Moreover, the viability of the bacterial population will be assessed to evaluate the frequencies to which the disinfection process is more effective in aquaculture context. The degradation of dissolved organic substances will be determined by chemical methods, e.g. GC-MS. A clear proof of the disinfection and cleaning effects for the user will be achieved by combing these methods.

With a successful completion of the project, common methods for disinfection and purification in aquaculture could be complemented with ultrasonic treatment and this offer a gate for a broader application within wastewater treatment industry and ballast water treatment. With the required adjustments of the work protocols the prototype will be able to process up to 10 m³/h wastewater and to operate in a RAS with a total volume up to 250 m³.