Abstract: Methods and systems are provided for wastewater treatment that yields zero liquid discharge (ZLD). These include pre-treating provided wastewater from any contaminated water source to remove heavy metals, ultra-filtering the pre-treated wastewater to remove suspended and colloidal solids, nano-filtering the ultra-filtered wastewater to yield treated water (with monovalent ions) and a concentrate, treating the concentrate to remove di- and tri-valent elements and other compounds from the concentrate, and to reduce a level of sulfates to a specified level which is above a solubility level of sulfates—to yield returned water, and sludge, mixing the returned water with the provided wastewater before or at the first treatment stage and/or with the pre-treated wastewater before the ultrafiltration, and removing residual water from the sludge to yield removed solids with ZLD. Advantageously, disclosed processes and systems are efficient, cheaper and more sustainable than prior art systems.

Abstract: Methods and systems are provided for industrial wastewater treatment that yields zero liquid discharge (ZLD). These include pre-treating provided industrial wastewater to remove heavy metals, ultra-filtering the pre-treated wastewater to remove suspended and colloidal solids, nano-filtering the ultra-filtered wastewater to yield treated water (with monovalent ions) and a concentrate, treating the concentrate to remove di- and tri-valent elements and other compounds from the concentrate, and to reduce a level of sulfates to a specified level which is above a solubility level of sulfates—to yield returned water, and sludge, mixing the returned water with the provided industrial wastewater before or at the first treatment stage and/or with the pre-treated wastewater before the ultrafiltration, and removing residual water from the sludge to yield removed solids with ZLD. Advantageously, disclosed processes and systems are efficient, cheaper and more sustainable than prior art systems.

Abstract: System (10) for electrocoagulatively removing contaminants from contaminated water (13), electrocoagulation reactor unit (16), and sedimentation column (302). Electrocoagulation reactor unit (16) includes reactor housing assembly (102) having: lower pair of integrally configured, and complementary upper pair of removably and replaceably configured, electrode positioning, spacing, holding elements, and, two wall electrode or electrode wall electrocoagulatively unreactive zones, each having an interior face of a side wall configured flush against and directly contacting adjacent, nearest neighboring, electrode face, for preventing water flowing and making contact therebetween. Sedimentation column (302) includes first sediments-water separator assembly having a water/sediments distributor assembly, and second sediments water separator assembly having downward flow multi-conduit assembly.