18 September 2017, News release from Omya International AG
New Remineralization Process for desalinated water providing stable, turbidity free pristine water quality
Wednesday September 27th 2017 at 9:00am PDT/ 6:00pm CEST / 5:00pm BST
Learn about Omya’s new and innovative desalinated water stabilization process known as “Omya Advanced Remineralization Process” (OARP) which exploits the technical and economic advantages that calcium carbonate has over lime and addresses the drawbacks of calcite contactors.
Over the course of the past few years, Omya has been working on processes that use Omyaqua® a micronized calcium carbonate for the remineralization of desalinated water and thereby exploit the technical and economic advantages that calcium carbonate has over lime, but at the same time address the drawbacks of calcite contactors, including its slow reactivity and large footprint required. The result is a new and innovative water stabilization process known as Omya Advanced Remineralization Process (OARP). At the heart of the patented process is the Membrane Calcite Reactor (MCR) – a reactor containing a submerged microfiltration membrane immersed in a suspension of micronized calcium carbonate. The use of modular components provides redundancy in the system, makes the process flexible in operation and allows for easy capacity expansions. Carbon dioxide is added to the calcium carbonate suspension, which in turns reacts to form a calcium bi-carbonate solution. The membrane acts as a barrier between the dissolved and undissolved calcium carbonate enabling a perfectly clear solution to be extracted from the reactor, and therefore ensuring a pristine water quality. This concentrated calcium bi-carbonate solution is then dosed into the desalination permeate to increase both the hardness and alkalinity of the mineral-deficient water. The use of submerged membranes prohibits the introduction of turbidity as seen in the current techniques, whether due to the precipitation of calcium carbonate within lime processes or from the loading of new product into the calcite contactors. The use of Omyaqua® micronized calcium carbonate with its specially engineered properties for rapid dissolution, in combination with the Membrane Calcite Reactor (MCR) allows for the generation of higher concentrations, and much decreased contact times with increased carbon dioxide efficiencies in comparison to calcite contactors. Short contact times also ensures the plant can respond very rapidly to changes in plant flow rate. Furthermore, a major advantage of the OARP process is the absence of generation of any backwash waste water since membrane backwash is made into the Membrane Calcite Reactor. This removes the requirement for backwash waste water treatment and sedimentation systems and thus allows for a zero-waste generating and handling process.
Nicholas Charles Nelson,
Head of Competence Centre for Water Treatment at Omya International
For further information please email Omya International AG