A Design of Water Injection System for Gas Turbine by Numerical Analysis at Garri Power Plant

Abstract

The Thermal power plants play an important role in converting chemical energy to electrical and heat energy.Gas turbines are used for power electrical generation, operating airplanes and for several industrial applications.At garri electrical stationThe gas turbine designed for power output 42 MW but because of many reasons (as specified by the International Standardization Organization (ISO) Therefore, the air inlet conditions are: air temperature 15 °C, relative humidity 60%, absolute pressure 101.325 k Pa at sea level) the actual power decreased to 30 MW, and the Environmental pollution increased according to the type of fuel used. So we will try the possibility of using a water injection system to avoid the pollutions (〖NO〗_x, 〖SO〗_x, CO) and also improving the over hall performance and efficiency. The objectives of this research are To Increase output power & efficiency produced from gas turbine and To Decrease environmental impact. Gas turbine power enhancement technologies such as water injection may have on the operational integrity of the gas turbine to reducing 〖NO〗_x formation also to reduce the flame temperature by introducing a water or steam into the flame zone. Both water and steams are very effective at achieving this goal. Generally, the amount of water is limited to the amount required to meet the 〖NO〗_x requirement in order to minimize operating cost. The results show that using water injection systems increased Net work output, efficiency and the heat rate. Without using water injection the total Network output was (30MW) and the efficiency about 29.3% but when we used the same flow rate of fuel and water .total Network output became 31.7MW an increase about (5.67%) also the efficiency become (31%)an increase about(5.8% )when we use water flow rate equal half of fuel flow rate total Net work output became 30.9MW an increase about (3%)also the efficiency become(31.2%)an increase about(6.47%) that’s mean the total work and the efficiency directly affected with the percentage of the water injection.