| Title | Study of the Selection of Gas Removal System in Geothermal Power Plant |
|---|---|
| Authors | Lina Agustina, Abdurrachim, Bambang Teguh Prasetyo |
| Year | 2013 |
| Conference | Indonesian Geothermal Association Conference |
| Keywords | geothermal, steam jet ejector, vacuum pump, motive steam, auxiliary power |
| Abstract | Utilization of the geothermal resource for power generation is always related to the presence of non condensable gases, as natural components of geothermal fluid. It is necessary to remove the gases in the condenser, in order to optimize thermodynamic efficiency of the power plants. The gases disturb the vacuum process in the condenser, lowering turbine efficiency and decreasing total power output of the power plant. There are 2 (two) types of gas removal system which are commonly used in Indonesia, i.e. steam jet ejector and liquid ring vacuum pump (LRVP). The optimum selection of gas removal system directly affects the power generation, steam consumption and the initial and operational cost of the geothermal power plant. Steam jet ejectors have no moving parts, therefore this is a relatively low-cost device. It requires low maintenance but need a lot of steam to operate the system. On the other hand, vacuum pump does not consume steam in the process but the cost of investment and maintenance can be more than steam jet ejector and consumes electricity. Steam jet ejectors are commonly used in the first generation of geothermal power plants in Indonesia. At present, new geothermal power plants like Kamojang geothermal power plant unit 4 utilize mostly a combination between vacuum pumps and steam jet ejectors (hybrid system), as alternatives to the steam jet ejectors only. The Kamojang geothermal power plant unit 2 and 3 use 2 (two) ejectors which are installed in series. The consumption of the steam is relatively high. The thesis evaluates and analyzes themodinamically and economically the substitution of steam jet ejectors system by hybrid system in Kamojang geothermal power plant unit 2 and 3 which has capacity 2x55 MW with referring to the experience of Kamojang geothermal power plant unit 4. From simulation, it was shown that total saving of steam consumption for hybrid system application in Kamojang geothermal power plant unit 2 and 3 is 397 kW (each plant). |