| abstract |
A process for removing sulfate includes combining a calcium compound and a fluid comprising sulfate to form a composition; adjusting the pH to be greater than or equal to 12; introducing, to the composition, an electrode comprising aluminum or a noble metal; contacting the composition with a material comprising aluminum if aluminum is absent from the electrode; applying a voltage to the electrode to oxidize the aluminum and to form aluminum ions; contacting the composition with the aluminum ions; and forming a precipitate to remove sulfate from the composition, the precipitate having a crystal structure including calcium, aluminum, and sulfate. A system for removing sulfate includes a first container to receive a composition comprising a calcium compound and a fluid comprising sulfate; a first transfer member to communicate the composition to a second container that includes a first electrode of and a second electrode to produce a precipitate of calcium, aluminum, and sulfate; and a second transfer member to communicate the precipitate and composition to a third container. |