Dry steam cycle application for excess steam utilization: Kamojang geothermal power plant case study. (March 2018)

• Record Type: Journal Article
• Authors: Prananto, Lukman Adi; Juangsa, Firman Bagja; Iqbal, Riza Mochamad; Aziz, Muhammad; Soelaiman, Tubagus Ahmad Fauzi
• Is Part Of: Renewable energy. Volume 117(2018)
• Page Start: 157
• Page End: 165
• Publication Date: 2018-03
• Subjects: Dry steam cycle -- Geothermal power plant -- Kamojang -- Steam jet ejector -- Liquid ring vacuum pump; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2017.10.029
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: This study investigated the utilization of available excess steam by the Kamojang geothermal power plant, which, owing to the vapor-domination of the steam, utilizes a dry steam cycle. A model of the system was validated against actual Kamojang Unit-2 data and found to produce accurate results within a low discrepancy level (<5% error). The modeled performance of the proposed system was obtained through optimization of the non-condensable gases (NCGs) gas removal system (GRS) based on heat balance calculations and assuming content of NCGs in the working fluid based on real operational data. To optimize the model, five GRS configurations were investigated: one-stage steam ejector, two-stage steam ejector, one-stage liquid ring vacuum pump (LRVP), two-stage LRVP, and hybrid system (ejector plus LRVP). To set constraints on the optimization, the allowable condenser pressure was defined based on the cooling water temperature and the maximum temperature difference. Under the best design configuration (a one-stage LRVP), the proposed plant generated a gross electric power of 15.9 MW with a parasitic power consumption of 755.2 kW. The proposed system to convert unused discharge steam into electricity suggests that its installation will result in an increase of the Kamojang geothermal power plant capacity. Highlights: Excess steam discharged to the atmosphere is utilized using dry-steam cycle. Model of the system was developed and validated against actual power plant. Gas removal system configurations are also examined for optimization. The proposed system can deliver additional 7.6% of power to the current capacity.