Systems and methods for recovering ammonium and phosphorus from liquid effluents

Patent metadata

Field	Value
Publication number	US-2016347630-A1
Application number	US-201615170129-A
Country	US
Kind code	A1
Filing date	Jun 1, 2016
Priority date	Jun 1, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

A system and method for capture of ammonia and phosphorus from an ammonia and phosphorus containing liquid effluent. The invention allows for the precipitation of phosphorus from said liquid effluent that has been under low aeration and has a pH of greater than about pH 9.

First claim

We claim:

1 . A system for reducing ammonia and phosphorus concentration in liquid effluents comprising: at least one gas permeable membrane manifold in an ammonia removal tank allowing for the diffusion of ammonia gas from said liquid effluent into said membrane in said manifold, a reservoir containing a stripping solution, a delivery system for (i) delivering the stripping solution from the reservoir to said membrane manifold to chemically change the ammonia gas to ammonia salts, and (ii) for carrying the salts to said a reservoir containing said stripping solution; wherein said delivery system comprises a pump having an intake end and a discharge end, and at least two hollow tubes, a first tube having one end attached to the discharge end of the pump and a second end attached to a first side of said gas permeable membrane manifold; and a second tube having a first end attached to a second side of said gas permeable membrane and a second end disposed above or in said reservoir for discharging ammonium salts to said reservoir; a reservoir containing a phosphorous precipitating agent, and a delivery system for adding the phosphorus precipitating agent to said effluent.

2 . The system of claim 1 further comprising adding a phosphorus precipitating compound to a liquid effluent having phosphorus in an amount to precipitate at least about 93% of said phosphorus in said liquid effluent wherein said liquid effluent has a pH greater than about 9.

3 . The system of claim 1 further comprising a phosphorus removal tank wherein said phosphorus precipitating compound is added to said phosphorus removal tank receiving liquid effluent from a ammonia removal tank having said gas permeable membrane manifold, wherein said effluent has been stripped of ammonia and has a pH greater than about 9.

4 . The system of claim 1 wherein said phosphorus precipitating compound is added to an ammonia separation tank of said system wherein said ammonia separation tank has at least one gas permeable membrane manifold and an ammonia and phosphorus containing liquid effluent under low aeration having a pH greater than about 9.5.

5 . A method for producing ammonium salt and phosphorus from an ammonia- and phosphorus-containing liquid effluent comprising:
capturing ammonia from a liquid effluent containing ammonia within the confines of a gas-permeable membrane manifold, contacting said ammonia with a stripping solution to produce ammonium salts, and transporting the salts to a reservoir for collection; adding a phosphorus precipitating agent to said liquid effluent, allowing said precipitated phosphorus to settle in a tank, and collecting said precipitated phosphorus.

Assignees

• Us Agriculture

Inventors

• Vanotti Matias B
• Szogi Ariel A
• Dube Patrick J

Classifications

• C02F2101/105

  Phosphorus compounds · CPC title

• B01D19/0031

  by filtration · CPC title

• C02F1/20

  by degassing, i.e. liberation of dissolved gases (degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D) · CPC title

• B01D21/01

  using flocculating agents (for purifying water C02F1/52; for liquid radioactive waste G21F9/10) · CPC title

• C02F1/5236 Primary

  using inorganic agents · CPC title