Improvement of Double-Flash geothermal power plant design: A comparison of six interstage heating processes

Abstract

In this paper, six different modifications of the Double-Flash power plants are proposed. These modifications are named "interstage heating" and consist of additional heat exchangers properly located in the system. The six interstage heating designs are analysed, optimized and then compared to an optimized Double-Flash reference power plant. The objective function is the power plant specific output (kJ/kg), and the design variables are the separator temperatures (°C) and the split fraction. Optimizations are performed for a wide range of reservoir temperatures (i.e., from 140 °C to 240 °C). Results show that interstage heating processes may increase the specific output of the plant by about 5%, decrease the liquid content in the low pressure turbine by about 50%, and decrease the required cooling capacity of the plant by about 10%. On the other hand, the analysis showed that the new designs proposed have negligible influence on the high pressure turbine liquid content or on the silica saturation coefficient. Keywords

Geothermal power plants with maximized specific power output: Optimal working fluid and operating conditions of subcritical and transcritical Organic Rankine Cycles

“…More specifically, the function fmincon.m is used with an "interior-point" algorithm (MathWorks, 2015). That algorithm has already been used in the context of thermodynamic cycle optimization in literature (e.g., Sarr and Mathieu-Potvin, 2015).…”

Analisis Thermodinamika dan Exergi pada Pembangkit Listrik Tenaga Panas Bumi Sistem Double flash yang menggunakan Interstage Heating

“…Interstage heating merupakan suatu konsep yang menambahkan heat exchanger kedalam sistem pembangkit sehingga dapat memanfaatkan panas internal pembangkit seefisien mungkin dengan tujuan untuk menaikan performa pembagkit. Konsep ini telah dibuat oleh Andrey Raymond Sarr (2015) [7] yang terinspirasi dari Mathieu-Potvin (2013) [8] and DiPippo (2013) [9]. Parameter yang sering menjadi pertimbangan ketika ingin merealisasikan suatu model pembangkit adalah daya output dan exergi, pada penelitian ini dilakukan analisis terhadap desain interstage heating dengan menggunakan analisis termodinamika secara keseluruhan dan analisis exergi yang difokuskan pada heat exchanger karena komponen utama pada interstage heating ini adalah heat exchanger, sehingga dapat terlihat performa setiap tipe pembangkit dan diperjelas fenomenanya dengan analisis exergi.…”

Improving the Environmental Sustainability of Flash Geothermal Power Plants—A Case Study

“…Double-or multiple-flash arrangements, including attractive, complex regenerative heat recovery schemes [20] are not here considered, because the BG3 architecture is already oriented toward the hybridization of a single-flash power plant through addition of an ORC cycle. Moreover, the well flow rate was maintained for all simulations at 121.9 kg/s, with a primary flash at 20 bar: this corresponds to optimal conditions for the present layout according to the well productivity curve, which should be marginally affected by the proposed layout improvements.…”