Evaluation of the performance of a new freeze desalination technology

Abstract

The use of desalination technologies which produce concentrated brines is acutely limited by inadequate waste brine disposal mechanisms such that the brine does not contaminate fresh water resources. The treatment of highly saline brine using freeze desalination technique trade marked as HybridICE TM technology was investigated at pilot scale. The capacity of the HybridICE TM process to generate fresh water by freeze desalination of brine was investigated in this study. Brine samples to feed into the HybridICE process unit were prepared in tanks with volume capacities between 1.0 and 10.0 m 3 by dissolving common salt into tape water. The effects of refrigerant temperature, initial brine concentration, energy consumption were evaluated in relation to product ice quality. Feed brine samples were processed in batches in a closed system where it was continuously re-circulated to generate product ice and more concentrated residual small volume of brine stream. The quality of ice produced could be turned into potable water it terms of its low total dissolved salts and conductivity. The salt removal, based on the average chloride concentration in the ice samples, was 96 %. The energy utilization efficiency amounted to an average of ZAR 10.0/m 3 water assuming energy cost of ZAR 0.39/kWh. The HybridICE TM technology was shown to be a better option than other desalination technologies currently in use, in terms of energy utilization and cleaner byproducts.

Freeze desalination as point-of-use water defluoridation technique

“…It is known that when soluble solutes freeze partially, a high extent of salt rejection occurs (Baker 1967;Melak et al 2016). However, the angle of the container used for freezing and surface roughness highly influence the inclusion of salt ions into the ice (Mtombeni et al 2013;Hao et al 2014).…”

Experimental of Seawater Desalination Using Thermosolar Energy

“…Given the shortage of fresh water in the world, water desalination has become a viable technique in many countries for more than 50 years (American Membrane Technology Association (AMTA), 2000; Fischetti, 2007;Youssef, Al-Dadah, & Mahmoud, 2014) and currently, around 44 Mm 3 of water is desalinated every day, (IDA Desalination, 2017), but is an intensive energy consumption process (Erlbeck et al, 2017), with a high environmental impact (Guevara & Stabridis, 2008). Freezing desalination has the advantage of being the most energy efficient process, being able to save up to 70%, with respect to the most used thermal techniques (Ahmad & Williams, 2011;Mtombeni, T., Maree, J.P., Zvinowanda, C, 2013), (Thermal desalination provide 62% of seawater desalted), in addition to other advantages, such as low corrosion, does not need pre-treatment (as reverse osmosis, which desalinates the largest amount of water in the world), and its high separation rate. (Johnson, 1979;Mandri et al, 2011;Rahman, Ahmed, & Chen, 2007).…”

Electrosorption for organic pollutants removal and desalination by graphite and activated carbon fiber composite electrodes

“…To achieve effective desalination, many physical and chemical methods have been widely investigated, including thermal dynamic method, chemical method and membrane method (Greenlee et al 2009;Jing et al 2009;Mtombeni et al 2013;Zhao et al 2011). As a novel method for seawater and industrial wastewater desalination, electrosorption has the unique features of low cost, high antipollution ability, environmentally friendly and simple operation (Wang et al 2012).…”