Testing of a dynamic simulation model for Recirculating Aquaculture Systems to support managerial decisions

Abstract

Economic evaluation for design and operation of Recirculating Aquaculture Systems (RAS) may effectively be supported by an appropriate dynamic simulation model. The complexity of the process requires a detailed analysis, while the experimental work is time consuming and expensive. However, this complexity is manageable for the new modelling methodologies. Accordingly, the problem solving capability can be essentially increased by combining experiments with computational model based studies. Considering the importance of the inherent coupling between structural and functional characteristics in design and control of RAS, Direct Computer Mapping (DCM) of programmable structures has been experimentally implemented for simulation of RAS aquaculture operation by the Research Group on Process Network Engineering in the past year. In the present work, the parameter sensitivity of RAS is studied with the help of the implemented model, using available data for African catfish (Clarias gariepinus) from the literature, as well as from experiments running at NARIC Research Institute for Fisheries and Aquaculture. From model development points of view, various semi-empirical and empirical formulation for weight increase, feed conversion rate, faecal and ammonia excretion, and mortality are applied. To allow further bio-economic calculations, the recent work focuses on the effect of the ratio of freshwater supply and the efficiency of the biofilter on the operation in a given stage of the process. The simulation model enables us to determine the economic impact of these factors.