Development of a Paddle Wheel Aerator for Small and Medium Fish Farmers in Nigeria

Pond aeration systems were developed to sustain large quantities of fish and biomass materials. In this study the importance and functions of aeration were examined and prototype paddle wheel aerator was developed. The main features of the paddle wheel aerator wereelectric motor used as prime mover which was of one horse power capacity, Paddle hubs with six paddles all mounted on a shaft made of stainless steel and brass materials. Aeration experiment was conducted in water basin made up of plastic. Paddle-wheel aerator performance evaluation was conducted using unsteady state test.Physico-chemicalproperties of water sampled from the tested ponds were determined in accordance with the American Public Health Association standards (APHA, 2005). Performance test carriedout showed that the overall oxygen transfer co-efficient (KLa) was observed to be as high as 8.19 hr -1 and standard oxygen transfer rate (SOTR) and standard aerator efficiency (SAE) ranged from 1.1 – 1.2 kgO2hr -1 and 1.1 – 1.3 kg O2KW -1 hr -1 respectively. The paddle wheel aerator improved the water quality by addition of oxygen leading to appreciable increase in the fish stock density which has been a major setback of low-income fish farmer in Nigeria.