Application of Airlift Pumps in the Aquaponics Industry

Abstract

Aquaponics is a combined food production system that cultivates fish and plants in a single self-sustaining loop. In this system, Fish waste is broken down by bacteria to be consumed as nutrients by plants. This reduces water toxicity due to waste accumulation. Aquaponics has recently gained popularity, but limited research and high operating costs have impeded the commercial growth in this field. The goal of this thesis is to utilize advanced airlift technology to reduce the overall cost and make this an economically viable industry. Traditional aquaponics systems utilize pumps and blowers for water circulation and aeration. In contrast, airlift pumps provide water conveyance and aeration thereby combining the two systems into one. An experimental study was conducted to evaluate the feasibility of a novel airlift pump in a mid-sized (2700 L) aquaponics system. Extensive data was collected and analysed including water quality, plant and fish health. A mass transfer model was formulated to predict the VMTC (Volumetric mass transfer coefficient) of the pump. This can be used as a predictive tool to design aquaponics systems and in the integration of airlift pumps in different applications.