Techno-economic assessment of minimal liquid discharge (MLD) treatment systems for saline wastewater (brine) management and treatment

The management and treatment of brine (saline wastewater) are of great importance, as its discharge to the environment poses a significant threat. A new strategy called minimal liquid discharge (MLD) appears to be a promising and more cost-effective option than zero liquid discharge (ZLD) as it uses only membrane-based technologies, leading to up to 95 % freshwater recovery. This research study introduces and presents for the first time a techno-economic assessment of five MLD treatment schemes that can be implemented in the brine treatment. The technologies included are reverse osmosis (RO), high-pressure RO, forward osmosis (FO), osmotically assisted RO (OARO), and membrane distillation (MD). Results showed that the MLD schemes costs ranged from US$0.79/m(3) to US$1.36/m(3), while the freshwater recovery ranged from 78 % to 89 %. In schemes 2 and 5, the implementation of MD substantially increased the energy consumption (>20 kW h/m(3)), however, these schemes were more economical (

Automated summary

Effective management and treatment of brine is crucial, with MLD technology showing promise for efficient water recovery. Cost and freshwater recovery varied among different MLD schemes, with some schemes showing increased energy consumption but greater cost-effectiveness.