Multiform Harvest Inc.

North Carolina State University

Washington State University

Ostara Nutrient Recovery Technologies Inc.

Keith E Bowers

Philip W Westerman

Shulin Chen

Tianxi Zhang

Joseph H Harrison

Methods and systems for removal and recovery of phosphorus from wastewater and producing inorganic phosphorus complexes including digestate recycle.

Methods and systems for recovering phosphorus from wastewater including digestate recycle

Methods and compositions for chemical drying and for producing struvite.

Methods and compositions for chemical drying and producing struvite

Methods and systems for recovery of phosphorus from wastewater and producing inorganic phosphorus complexes.

Process and system for recovering phosphorus from wastewater

Particular aspects provide a method for recovering phosphate, comprising: obtaining an effluent or wastewater, etc. having calcium-sequestered phosphate; adding to the effluent or wastewater a calcium chelating or sequestration agent suitable to chelate or sequester Caions from the calcium-sequestered phosphate to facilitate release of phosphate from the calcium-sequestered phosphate; transferring, facilitated by said Caion capture and in the presence of sufficient concentrations of NHand Mgions, of the phosphate into struvite (magnesium ammonium phosphate hexahydrate or MgNHPO.6HO), or hydrated magnesium ammonium complex of phosphate; and recovering the struvite, or the formed hydrated magnesium ammonium complex. Preferably, the method further comprises acidification of the effluent or wastewater to facilitate release of Caions from the calcium-sequestered phosphate and chelation of sequestration of the Caions by the calcium chelating or sequestration agent. Additional aspects provide a phosphate-containing fertilizer comprising struvite, and methods for making same.

Compositions and methods for wastewater treatment

An apparatus and method for removing phosphorus from a wastewater effluent stream from a hog waste lagoon. The wastewater effluent is introduced to the bottom of an inverted cone-shaped continuous crystallizer including a fluidized bed of struvite therein. An effective amount of ammonia is introduced to the wastewater effluent at the bottom of the crystallizer to elevate the pH of wastewater effluent a predetermined amount. An effective amount of magnesium is also introduced to the wastewater effluent at the bottom of the crystallizer. The composition adjusted wastewater effluent is then continuously passed upwardly through the fluidized bed of struvite to reduce the total phosphorus content of the wastewater effluent a predetermined amount of up to about 80% or more. The treated wastewater effluent stream is removed from the top of the crystallizer, and struvite crystals that grow large enough to sink from the bottom of the crystallizer are periodically removed from a collection chamber therebeneath.

Growing community of inventors

Seattle, WA, United States of America

Keith E Bowers