The heart of the Crystalactor installation is the pellet reactor, partially filled with a suitable seed material such as sand or the target mineral. Feed water is pumped in an upward direction at a superficial velocity of about 40-100 m/h, depending on the application. To crystallize the target component(s) on the pellet bed, a driving force is created by a reagent dosage and for pH adjustment and/or reaching supersaturation. By selecting the appropriate process conditions, co-crystallization of impurities is minimised, and high-purity crystals (pellets) are obtained. The pellets grow and move towards the reactor bottom by gravity.
Research and practice have demonstrated that maximizing the specific surface (m2 pellet surface per m3 reactor volume) near the reactor bottom is the key to the successful operation of the pellet reactors. This requires an integrated approach and control of the hydraulic load, reagent dosing of base and supersaturation.
Intermittently, a quantity of the largest fluidized pellets is discharged from the reactor and fresh seeding material is added. After atmospheric drying, readily handled pellets are obtained and the need for sludge dewatering, drying or hauling of sludge is eliminated. These pellets can be transported for reuse and/or commercial resource recovery, which contributes positively financially to an overall business case.
Product Manager Crystalactor