Oxygen Transfer in Anoxic Water using a Dispositive of Paddle Wheel Aerators at Low Revolutions

Abstract

The reduction of dissolved oxygen (DO) in water is associated with the effect of climate change. The lack of oxygen in water bodies directly affects the biological species present in different shallow water bodies such as swamps and wetlands, as well as in aquaculture processes. An optimal value in the DO concentration favors the reproduction of these biological species present in both artificial and natural environments. For this, various equipment has been developed to favor the increase of DO in the water to acceptable values. However, some of these systems are expensive, energy inefficient, and noisy which generate adverse impacts in aquatic ecosystems due to perturbances in the water. This study measures the efficiency (KgO2·kWh-1) of introducing DO into the water using a paddle wheel aerator system at low RPMs destined for shallow bodies of water. Tests were performed on anoxic water samples using aerators with 6, 12, and 24 paddles at the laboratory level. By increasing the voltage (6, 9, and 12V), the RPMs applied to each device through a geared motor is also increased. The results show a higher DO transfer rate in the 1 and 5 mg of O2·L-1 range. The best configuration concerning energy consumption worked at low RPMs using the 6-paddle wheel aerator at 6V. This establishes that, in addition to the management of low revolutions, the use of a smaller number of wheels favors an increase in efficiency during the DO restoration process in shallow water bodies.