Demonstration scale chemical–physical treatment and agricultural reuse of highly saline textile wastewater

Abstract

This study aimed to develop an energy‐efficient process for treating highly saline textile wastewater (TWW) in a 10 m3/day pilot plant and evaluate forage sorghum irrigation with treated wastewater in terms of crop production and soil and irrigation device performance. The TWW treatment pilot plant, consisting of a coagulation/flocculation unit followed by a sand filter and an anion exchange resin column, produced treated effluent that complied with the permissible limits specified in the ISO 16075‐2:2020 standard for Category C irrigation water. The corresponding average energy consumption was 1.77 kWh/m3. Reusing treated TWW for forage sorghum irrigation over a 13‐week cycle yielded crop performances comparable with freshwater irrigation, with no negative impact on the irrigation system. Although soil profiles were similar between treated TWW and freshwater irrigation, both soils featured an increase in electrical conductivity, which may reversibly or irreversibly affect soil quality and damage salt‐sensitive crops. These findings demonstrate the effective treatment and reuse of saline TWW for irrigating salt‐tolerant crops, offering significant implications for industrial wastewater management and cropping patterns in arid and semi‐arid regions.