THERMODYNAMIC STUDY OF BINARY CYCLE LAHENDONG GEOTHERMAL POWER PLANT

• Main Author: GOZALY (NIM : 13106109); Pembimbing : Dr. Ir. Ari Darmawan Pasek; Prof. Dr. Ir. T. A. Fauzi S., JOAN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/16176
• Institution: Institut Teknologi Bandung

Geothermal energy is one form of energy that is clean and abundant in Indonesia. Geothermal is one form of alternative energy that can replace fossil energy which is more harmfull to the environment. Geothermal fluid produced <br /> <br /> <br /> from production wells is usually in the form of fluid mixture between brine (liquid phase) and vapor. Geothermal power plant cycle generally use only the vapor form, whereas the brine can be used also because they still have enough energy. <br /> <br /> <br /> This final project concerns about brine used in binary cycle geothermal power plant. The data is taken from one of many wells in Lahendong. In binary cycle geothermal power plant, brine acts as a heat source that will vaporize a <br /> <br /> <br /> secondary working fluid. The secondary working fluid vapor will rotate turbine and generator to generate electrical power. Secondary working fluid that can be used in binary cycle for among others are iso-pentane, normal pentane, iso-butane, and normal-butane. To get the best secondary working fluid that generates the largest net electrical power, a study must be conducted on these fluids. <br /> <br /> <br /> The study shows that parameters that affect the performance of the binary cycle are the kind of secondary working fluid; the working pressure of the evaporator; the heat exchanger pinch temperature; the type and the possibility to make the heat exchanger; and the silica content in brine. Preferred working fluid chosen for a binary cycle for one of many wells in Lahendong is normal-pentane. <br /> <br /> <br /> The selected working conditions are 147 o kPa evaporator pressure and 5oC pinch temperatur. Beside the above study, this final project also designed the heat exchanger <br /> <br /> <br /> components consisting of preheater, evaporator, and condenser. Preheater AET was designed in 1.45 m shell diameter; 7.315 m long tube; using 1 inch BWG 16 <br /> <br /> <br /> pipe arranged at an angle of 45o. Evaporator was designed to have the type of AKT with 1.4 m shell diameter; 9.753 m long tube; and also using 1 inch BWG 16 pipe which is arranged at an angle of 45o. Tube material for the preheater and the evaporator is Duplex Stainless Steel SAF 2205 whereas the material for the shell is ASTM A516-60. Condenser was designed to use air cooling media; will <br /> <br /> <br /> has dimension of 14x19 m, using six induced flow fans with 4.7 m diameter for each fan, and requires 624 kW power. Net power correction result after the heat exchanger design is 2.7 MW.