SEPARATION OF NATIVE NANO-DISPERSE CLAY SORBENT SUSPENSION BY FLOCCULATION AND SEDIMENTATION

The growth of industrial and agricultural production inevitably leads to an increase in freshwater deficiency, and this is indeed observed on all continents of our planet. The only way to overcome this challenging problem is to develop effective methods for purifying circulating water from dispersed and soluble substances, including heavy metal ions and water-soluble components petroleum products (Toluene, Benzene, Phenol, and similar ones.) It is generally recognised that the simplest, most accessible, and cheapest way to purify water from soluble contaminants is the use of ultrafine clay sorbents. Studies on the process of separating clay suspensions have been conducted using samples of clays mined from deposits in Ukraine. The samples were treated with anionic flocculants. The effectiveness of flocculants, their optimal dose, and the optimal medium shear rate in the flocculator were defined using the device UltraFloc-Tester “UFT-TFS-029”. It was found that, depending on the properties of the clay, the treatment of the clay suspension (3 g/l) for 6 seconds in a flocculator at a medium shear rate of 1000–1500 s-1 followed by subsequent separation in a flow-through horizontal micro-settler for 55 seconds, allowed to achieve the residual suspension concentration around 0.18–0.42 g/l. Additionally, it has been found that Magnafloc 5250 can be regarded as the most effective and commonly used all-purpose flocculant for the studied clay suspensions.