Treatment of an industrial wastewater for phosphorus and fluoride recovery by a process coupling block freeze concentration and precipitation

Sustainable production of activated carbon from indigenous Acacia etbaica tree branches employing microwave induced and low temperature activation

“…In the present study, Phosphoric acid was used as an activating agent with the precursor material ( Acacia etbaica tree branches) as it can increase the porous structure, provide high surface area and total pore volume, which in turn increases the yield, adsorption capacity, active free valances, surface reactivity, and thermal stability [ 23 , 24 ]. Furthermore, it was easy to treat the wastewater produced during the washing of activated carbon, either by addition of metal salts to precipitates that were removed by solids separation processes, by evaporation in treatment basins or by neutralisation with calcium salts [ 25 ].…”

Eco-friendly and sustainability assessment of technologies for nutrient recovery from human urine—a review

“…Because of the density variance between ice and salt, both solids can be easily separated by gravity (Moriwaki et al, 2020). This technology is employed in eutectic freeze crystallization in industrial operations and wastewater purification as a low-energy and effective purification technique (Guessous et al, 2023;Hu et al, 2023). Lind et al (2001) observed that by subjecting urine to a temperature of −14°C, it is possible to concentrate around 80% of the nutrients in just 25% of the original volume.…”

Study on the effect of an ultrasound assisted reaction on the crystallization properties of recovered cryolite

“…16 However, these methods generate a large amount of high concentration uoride wastewater during the treatment process, which has become a thorny problem. 17,18 The common treatment methods for uoride containing wastewater include chemical precipitation method, 19 coagulation precipitation method, 20 crystallization precipitation method, 21 adsorption method, 22 ion exchange method, 23 etc. Some methods have problems such as complex equipment, large operating capacity, high energy consumption, and high treatment cost in the treatment process, making it difficult to be widely applied.…”