TECHNICAL STUDY OF WATER PURIFICATION FROM WATER DOMINATED GEOTHERMAL BRINE FIELD USING LIME SODA TECHNIQUE AND DIRECT CONTACT MEMBRANE DISTILLATION

• Main Author: Delonix Regia Sugiarto, Lanang
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/87141
• Institution: Institut Teknologi Bandung

Geothermal brine is an alternative source for lithium, silica, and water. The increasing demand for raw materials used in electric batteries highlights the importance of lithium extraction from geothermal brine. Furthermore, excess brine in geothermal fields, which is often not fully reinjected due to evaporation in ponds, can be utilized as a raw material for producing environmentally friendly hydrogen. This study simulates the purification process of geothermal brine to simultaneously enhance lithium concentration, purify water, and separate silica. The process involves pretreatment and separation of the brine, with simulations conducted using Aspen Plus® and MATLAB software. The preliminary design indicates that the brine stream can produce 63.83 kg per batch of silica sludge in the form of CaSiO?, requiring 75.9 kg per batch of lime. The system is capable of producing 30 tons per hour of distilled water, offering the potential to generate 3,357.5 kg of hydrogen gas per hour in a 185 MW setup. The treated brine achieves an Mg/Li ratio of 8,26 ×10?6, with a final lithium concentration of 212.29 ppm—representing a 9.39-fold increase from the initial lithium concentration in the brine.