Sustainable management of hypersaline brine waste: Zero liquid discharge via Joule-heating at supercritical condition

Abstract

Supercritical water desalination is an increasingly attractive alternative treatment methodology for hypersaline brine (produced water) waste streams generated by oil/gas wells. The Joule-heating method provided in this study allows for internal heating of high conductivity fluids, reducing thermal lag and heat losses endemic to external heating methods. This study directly compares the aforementioned method for treating field-derived produced water from a Utica-Point Pleasant Shale well located in Noble County, Ohio with previous results using simulated brines. Experimental results from a prototype process are provided at operating pressures of 230 and 250 bar. At these pressures, a clean vapor was produced with total dissolved solids (TDS) levels of 608.73 ± 57.36 and 1174.52 ± 131.3 mg·L−1, respectively. The liquid outlet was processed through an additional flash vessel to assess further water recovery, producing an additional clean product with a TDS level of 618.0 ± 34.2 mg·L−1. A two-stage flash system model was assessed for the desalinator outlet, introducing a workable design for a zero liquid discharge (ZLD) system at all appropriate brine salt concentrations.