Life Cycle Comparison of Two Ro Concentrate Reduction Technologies

Desalination and water reuse technologies are critical for solving water problems. Unlocking water resources through the minimization of reverse osmosis (RO) concentrate volume offers sustainable opportunities to meet the challenge. A pellet softening lime intermediate concentrate chemical stabilization (ICCS) reactor and a conventional lime softening ICCS for the treatment of RO concentrate were evaluated. Process performance, footprint, chemical usage, energy consumption, residual volume and dewatering characteristics for the conventional and pellet softening ICCS were compared. To evaluate the overall environmental impact of the two ICCS, a process based Life Cycle Assessment (LCA) was performed for the conventional and pellet softening ICCS technologies. The LCA quantifies the resource and energy needs and wastes generation through the process’ life from raw material acquisition to production, use, and disposal. It is based on careful energy and materials balances for all stages. The LCA factored resource inputs (minerals, fossil fuels, land use, etc.) and environmental outputs (damage to natural resources, ecosystem quality and human health, air emissions, toxicityweighting, global warming potential, ozone depletion potential, eutrophication potential, etc.). This paper will present a comprehensive comparison of the two ICCS technologies including pilot testing results and LCA.