Nutrient extraction and recovery device for isolation and separation of target products from animal produced waste streams

Patent metadata

Field	Value
Publication number	US-10329206-B2
Application number	US-201615381258-A
Country	US
Kind code	B2
Filing date	Dec 16, 2016
Priority date	Dec 16, 2015
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

The present invention provides for nutrient extraction and recovery devices that use the Donnan Membrane Principle (DMP) to cause spontaneous separation of dissolved ions along electrochemical potential gradients, wherein anions and cations such as H 2 PO 4 − , HPO 4 2− , PO 4 3− , Mg 2+ , Ca 2+ , NH 4 + , and K + are moved from manure containing waste streams through cation and anion exchange membranes into a recovery stream thereby precipitating target compounds including but not limited to struvite, potassium struvite and hydroxyapatite.

First claim

That which is claimed is:

1. A process for treating manure in order to isolate a target precipitate, the process comprising:
a) providing a manure medium;
b) introducing the manure medium into a separating system comprising:
a waste compartment and a recovery compartment positioned within the waste compartment, wherein the recovery compartment comprises at least one cation exchange membrane and at least one anion exchange membrane, wherein the at least one cation exchange membrane and the at least one anion exchange membrane are positioned on opposite or adjacent sides on the recovery compartment, and wherein the recovery compartment comprises an inlet and outlet for moving a recovery stream therethrough, and wherein the recovery stream comprises an ionic solution comprising at least one cation and at least one anion, wherein the at least one cation is selected from the group consisting of Na + , K + , and NH 4 + , and the at least one anion is selected from the group consisting of HPO 4 2− Cl − , HO − , HCO 3 − , and HCOO − ; and
c) moving the manure medium into the waste compartment, wherein the manure medium contacts both the at least one cation exchange membrane and the at least one anion exchange membrane, wherein anions in the manure medium will pass through the anion exchange membrane into the recovery stream and cations in the manure medium will pass through the cation exchange membrane into the recovery stream, wherein ions in the recovery stream form a precipitate.

2. The process of claim 1 , wherein the manure medium comprises at least one species selected from the group consisting of H 3 PO 4 , H 2 PO 4 − , HPO 4 2− , PO 4 3− , Ca 2+ , Mg 2+ , NH 4 + , and K + ions.

3. The process of claim 1 , wherein the precipitate is struvite, potassium struvite, or hydroxyapatite.

4. The process of claim 3 , wherein the struvite, potassium struvite, or hydroxyapatite is removed from the recovery stream and used as a fertilizer.

5. The process of claim 1 , wherein the recovery stream has a pH ranging from about 7 to 11.

6. The process of claim 1 , wherein the at least one cation exchange membrane comprises a polymer containing anionic groups including sulfonic and/or carboxylic groups.

7. The process of claim 1 , wherein the anion exchange membrane comprises a polymer containing quaternary or tertiary amine groups.

8. The process of claim 1 , wherein the manure medium is mechanically pretreated to remove any unwanted material, larger solids and excess liquids, wherein the pretreating is selected from screw pressing, centrifuging, vibrate screening, mesh screening, belt filtering, or hydrocycloning.

9. The process of claim 8 , wherein the pretreated manure medium is dehydrated to minimize water content thereby forming a solid fertilizer.

10. The process of claim 2 , wherein the HPO 4 2− anions in the manure medium will pass through the at least one anion exchange membrane into the recovery stream and Mg 2+ and NH 4 + cations in the manure medium will pass through the at least one cation exchange membrane into the recovery stream, wherein a substantially equal amount of Na + cations and Cl − anions from the recovery stream will move into manure medium, and wherein ions in the recovery stream form a struvite, potassium struvite or hydroxyapatite precipitate thereby reestablishing an electrochemical potential gradient across the at least one cation and at least one anion exchange membrane to provide for additional movement of ions through the at least one anion and the at least one cation exchange membranes.

11. The process of claim 10 , where the struvite, potassium struvite or hydroxyapatite is removed from the recovery stream by a separation method.

12. The process of claim 10 , wherein the recovery stream has a pH ranging from about 7 to 11.

13. The process of claim 10 , wherein the cationic exchange membrane comprises a polymer containing anionic groups including sulfonic and/or carboxylic groups.

14. The process of claim 10 , wherein the anion exchange membrane comprises a polymer containing quaternary or tertiary amine groups.

15. The process of claim 10 , wherein the manure medium is mechanically pretreated to remove any unwanted material, larger solids and excess liquids, wherein the pretreating is selected from screw pressing, centrifuging, vibrate screening, mesh screening, belt filtering, or hydrocycloning.

16. A process for treating manure in order to isolate at least one target precipitate, the process comprising:
providing a manure medium;
introducing the manure medium into a recovery system comprising:
a first and second waste compartment and a recovery compartment positioned between the first and second waste compartments, wherein the first and second waste compartments comprise an inlet and outlet for moving a first and second waste stream therethrough, respectively, wherein the recovery compartment comprises an inlet and outlet for moving a recovery stream therethrough, and wherein the first waste compartment is separated from the recovery compartment by at least one anion exchange membrane and the second waste compartment is separated from the recovery compartment by at least one cation exchange membrane;

separating the manure medium into the first and second waste streams for introducing into the inlet of the first and second waste compartments, respectively;
introducing an ionic solution comprising at least one cation and at least one anion, wherein the at least one cation is selected from the group consisting of Na + , K + , and NH 4 + , and the at least one anion is selected from the group consisting of HPO 4 2− Cl − , HO − , HCO 3 − , and HCOO − into the recovery stream, wherein anions in the first waste stream will pass through the at least one anion exchange membrane into the recovery stream and cations in the second waste stream will pass through the at least one cation exchange membrane into the recovery stream, wherein a substantially equal amount of cations and anions from the recovery stream will move into the respective first and second waste stream, and wherein ions in the recovery stream form a precipitate comprising struvite, potassium struvite and/or hydroxyapatite thereby reestablishing an electrochemical potential gradient across the at least one cation and at least one anion exchange membranes to provide for additional movement of ions through the anion and cation exchange membranes thereby forming additional precipitate.

Assignees

• Blaney Lee
• Univ Maryland

Inventors

• Blaney Lee

Classifications

• C05B7/00 Primary

  Fertilisers based essentially on alkali or ammonium orthophosphates (C05B11/00 takes precedence) · CPC title

• A01C3/00

  Treating manure; Manuring · CPC title

• C05B17/00

  Other phosphatic fertilisers, e.g. soft rock phosphates, bone meal · CPC title

• B01D15/363

  Anion-exchange · CPC title

• B01D17/0217

  by centrifugal force · CPC title