A Comprehensive Geothermal System in the Usage of Oilfield Associated Water from Abandoned Oil Wells

orc2019 Tracking Number 153

High water-cut oil wells are weak in exploitation of crude oil but cost a lot for maintenance, an appropriate way to deal with this problem is making full use of the waste heat from the oilfield associated water. A comprehensive geothermal system was proposed to the cascade utilization of the geothermal water from the oil well, and it consisted of a power generation system based on organic Rankine cycle (ORC), a gathering heat tracing system, an absorption refrigeration system for house cooling, and a house heating system. Exergy and sensitivity analysis about the ambient temperature were conducted to evaluate the thermal performance of the comprehensive system, and heat consumption equivalent was applied to assess its economic performance. Results showed that the best evaporating pressure of ORC subsystem was 650kPa, and the overall system could work with a exergy efficiency higher than 42.5% the whole year. Moreover, nearly 8916 tons of kgce could be saved every year. The work done may provide some guidance for researchers in the usage of the geothermal water based on high-cut oil wells.