Patent ID: 11897791
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Environmental technology (Chemistry)
Classification: CPC C | IPC C

Claim 7:
8. A method comprising:
flowing a blowdown water stream from a cooling tower to a blowdown water storage tank, the blowdown water comprising phosphorus;
flowing the blowdown water stream from the blowdown water storage tank to an ion exchange vessel, the ion exchange vessel comprising an ion exchange resin packing;
contacting the blowdown water stream with the ion exchange resin packing, such that at least a portion of the phosphorus from the blowdown water stream adsorbs to the ion exchange resin packing to produce a water stream having a phosphorus content that is less than a phosphorus content of the blowdown water stream;
flowing a regenerant stream from a regenerant storage tank to the ion exchange vessel, the regenerant stream comprising sodium chloride;
contacting the regenerant stream with the ion exchange resin packing, such that at least a portion of the phosphorus that has adsorbed to the ion exchange resin packing, desorbs from the ion exchange resin packing to produce a spent regenerant stream;
flowing the spent regenerant stream from the ion exchange vessel to a reaction vessel;
flowing a first reactant stream to the reaction vessel, the first reactant stream comprising magnesium ions;
flowing a second reactant stream to the reaction vessel, the second reactant stream comprising ammonium ions;
mixing the spent regenerant stream, the first reactant stream, and the second reactant stream in the reaction vessel to produce a product comprising struvite;
flowing at least a portion of the water stream from the ion exchange vessel to a first backwash storage tank;
circulating at least the portion of the water stream back from the first backwash storage tank to the ion exchange vessel to remove at least a portion of solids from the ion exchange resin packing to produce a backwash stream;
flowing the backwash stream from the ion exchange vessel to a second backwash storage tank; and
storing the backwash stream in the second backwash storage tank for subsequent processing or disposal.