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improve the efficiency of biological-activated carbon filters through a combination of biodegradation and adsorption (Lu et al. 2020).
5.2.2.20 Reverse Osmosis
The wastewater after the secondary treatment, filtration and activated carbon filter is
further treated with reverse osmosis based on end-use requirement. Reverse osmosis
is already explained in Sect. 5.2.1.8.
5.2.2.21 Electrodialysis
Electrodialysis is a separation process in which ions move through an ion-selective
membrane under the influence of an electric field.
5.2.2.22 Air Stripping
Air stripping is a process in which volatile compounds in a liquid is driven into air.
The contaminants stripped include ethylbenzene, xylene, benzene, toluene and
ammonia. In this process, water contaminated with volatile pollutants are sprayed in
a tower where in volatile contaminants move out of contaminated water.
5.2.2.23 Ion Exchange
Ion exchange is done after secondary treatment and removal of suspended solids in
filtration and organic matter in activated carbon filter. The process is already briefly
explained in Sect. 5.2.1.6.
5.2.2.24 Sludge-Drying Beds
Sludge-drying beds are provided to allow excess sludge that is removed from the
process to dry for easier handling. Improper operation often leads to poor sludge
handling that leads to non-usability of sludge drying beds making them hard with
plants growing on it (Fig. 5.13).
5.2.2.25 Sludge Thickening
Sludge thickening is a process of reducing the volume of sludge by removal of free
water in sludge. Thickening is done by vacuum filtration, centrifugation, gravity and
floatation.
5.2 Engineering Control
improve the efficiency of biological-activated carbon filters through a combination of biodegradation and adsorption (Lu et al. 2020).
5.2.2.20 Reverse Osmosis
The wastewater after the secondary treatment, filtration and activated carbon filter is
further treated with reverse osmosis based on end-use requirement. Reverse osmosis
is already explained in Sect. 5.2.1.8.
5.2.2.21 Electrodialysis
Electrodialysis is a separation process in which ions move through an ion-selective
membrane under the influence of an electric field.
5.2.2.22 Air Stripping
Air stripping is a process in which volatile compounds in a liquid is driven into air.
The contaminants stripped include ethylbenzene, xylene, benzene, toluene and
ammonia. In this process, water contaminated with volatile pollutants are sprayed in
a tower where in volatile contaminants move out of contaminated water.
5.2.2.23 Ion Exchange
Ion exchange is done after secondary treatment and removal of suspended solids in
filtration and organic matter in activated carbon filter. The process is already briefly
explained in Sect. 5.2.1.6.
5.2.2.24 Sludge-Drying Beds
Sludge-drying beds are provided to allow excess sludge that is removed from the
process to dry for easier handling. Improper operation often leads to poor sludge
handling that leads to non-usability of sludge drying beds making them hard with
plants growing on it (Fig. 5.13).
5.2.2.25 Sludge Thickening
Sludge thickening is a process of reducing the volume of sludge by removal of free
water in sludge. Thickening is done by vacuum filtration, centrifugation, gravity and
floatation.
5.2 Engineering Control