| Title | Design and Experimental Validation of Heat Exchangers Equipment for 2 kW Model of Binary Cycle Power Plant |
|---|---|
| Authors | Bambang Teguh P., Himawan S., Suyanto, Taufan S., MD Trisno |
| Year | 2010 |
| Conference | World Geothermal Congress |
| Keywords | geothermal, binary cycle, n-pentane, thermal waste, brine, heat exchangers, turbine |
| Abstract | Currently, 100% of brine at direct-steam geothermal power plant is injected into injection wells. Injected brine generally has a temperature higher than 100oC and mass flow rate around hundred of ton/hour. The rapid estimation showed the content of rejected energy is around hundred millions of watts. Binary cycle plant may be advantageous technology to recover this energy waste. In order to study the implementation above technology, BPPT has developed the 2 kW model of binary cycle power plant using the thermal energy of brine. In this plant, thermal energy of brine is transferred via a heat exchanger to working fluid for use in a fairly conventional Rankine cycle. The power cycle consists of an evaporator, a turbine-generator, a condenser, and feed pump. Other equipment is cooling tower to serve the condenser cooling water. The working fluid used in this plant is n-pentane to achieve a good thermodynamic match to the particular characteristics of brine, especially brine temperature. This paper presents the design and testing of heat exchangers equipments and n-pentane turbine of this binary cycle plant model. From design analysis the heat exchanger equipment to be used are 56.31 kW shell and tube evaporator, 53.68 kW shell and tube condenser. The turbine design is single-stage impulse turbine with five convergent nozzles, 382.3 mm rotor diameter, 60 blades, 16.5 mm height of blade, and 10 mm width of blade. This turbine is designed to operate at 3000 rpm and 65.6% turbine efficiency. Experimental result showed that the system has successfully produced 1.2 kWe. There is 8.5% different in efficiency lower than design condition The method of design and the result of experiment will be discussed in this paper. |