Feasibility of Using Air Lift Pump for Lifting Raw water from Turbine shaft Seal in Rosaries hydro-power Plant

Abstract

The pressure effect on performance of airlift pump (ALP) was examined experimentally, to use in turbine pit of Rosaries power station. An airlift pump is a device that pumps a liquid or slurry using only gas injection. In this study, the liquid used was water and the injected gas was air. The effect of the pressure was determined by measuring the water discharge from an airlift pump with constant submergence ratio (SR) and main diameter of pump (101.6mm and 7.5mm nozzle diameter), then repeating the tests with changing the submergence ratio and total lift (TL) . For total lift three types of pumps was used, one pump (lift=150cm and SR=30.23%), two pumps (lift=75cm and SR=46.43% for each) in series and three pumps (lift=50cm and SR=56.52% for each) in series. The induced water flow was measured using an accumulated rigid tank. Tests were run for air pressures ranging from 3 to 12 bars gauge. The result show that water flow increased with pressure increase till the optimum point and then decrease, and optimum pump to used is two pumps(lift=75cm and SR=46.43% for each) in series with absolute pressure 10 bar.