Organic containing sludge to fertilizer alkaline conversion process

• US 8,202,342 B2
• Filed: 05/09/2011
• Issued: 06/19/2012
• Est. Priority Date: 09/15/2005
• Status: Active Grant

• Current Assignee: Profile Products LLC
• Original Assignee: Vitag Corporation
• Inventors: Burnham, Jeffrey C.
• Primary Examiner(s): LANGEL, WAYNE A
• Application Number:
  US13/103,637
• Publication Number:
  US 20110265533A1
• Time in Patent Office: 407 Days
• Field of Search: 71/11, 71/12, 71/13, 71/14, 71/15, 71/17, 71/21, 71/22, 71/25, 71/640.3, 71/641.3
• US Class Current: 71/11
• CPC Class Codes: A45D 20/18 Flexible caps with provision for hot air supply
• CPC Class Codes: C02F 11/06 by oxidation incinerators for burning waste liquors, e.g. sulfite liquor from paper-making plant F23G7/04
• CPC Class Codes: C05B 17/00 Other phosphatic fertilisers, e.g. soft rock phosphates, bone meal
• CPC Class Codes: C05C 11/00 Other nitrogenous fertilisers
• CPC Class Codes: C05C 3/00 Fertilisers containing other salts of ammonia or ammonia itself, e.g. gas liquor
• CPC Class Codes: C05C 7/00 Fertilisers containing calcium or other cyanamides
• CPC Class Codes: C05D 3/02 from limestone, calcium carbonate, calcium hydrate, slaked lime, calcium oxide, waste calcium products
• CPC Class Codes: C05F 11/00 Other organic fertilisers
• CPC Class Codes: C05F 3/00 Fertilisers from human or animal excrements, e.g. manure
• CPC Class Codes: C05F 5/008 Waste from biochemical processing of material, e.g. fermentation, breweries
• CPC Class Codes: C05F 7/00 Fertilisers from waste water, sewage sludge, sea slime, ooze or similar masses
• CPC Class Codes: C05F 9/00 Fertilisers from household or town refuse
• CPC Class Codes: C05G 3/20 for preventing the fertilisers being reduced to powder; Anti-dusting additives
• CPC Class Codes: Y02P 20/145 the feedstock being materials of biological origin
• CPC Class Codes: Y02W 30/40 Bio-organic fraction processing; Production of fertilisers from the organic fraction of waste or refuse

Abstract

This invention is directed to systems, devices and methods for treating organic-containing sludges and converting such sludges to high value fertilizers containing both inorganic and organic fertilizer components, which creates an inorganically-augmented bioorganic fertilizer. The invention describes methods to create a thixotrophic or paste-like material via the application of mixing energy to the organic sludge followed by an alkaline treatment and a subsequent ammoniation. The invention further describes a method to increase the plant nutrient content in the organic containing product to a level which permits the finished granular fertilizer product to compete in the commercial agricultural fertilizer marketplace. Further, the invention reduces odors associated with said organic-containing sludges.

Claims

1. A method of fertilizer manufacture comprising:

creating a thixotropic paste from a composition containing biosolids;

adding an oxidizing agent to the paste;

adding a first amount of ammonia to the paste to produce a pH of 10 or higher;

adding an acid to the paste to produce heat and at pH 7.0 or less and a second amount of ammonia to the paste to raise the concentration of free ammonia to above 10,000 ppm;

adding a granulating agent to the paste;

extruding or granulating the paste; and

drying the extruded or granulated paste to a dryness of 90% or more of solids.

2. The method of claim 1, wherein biosolids are selected from the group consisting of municipal biosolids and sludges, manures and animal residuals, lagoon sludges, organic-containing sludges produced from food fermentation, sludge waste products, pharmaceutical fermentation waste, industrial fermentation products, and mixtures and combinations thereof.

3. The method of claim 1, wherein the oxidizing agent is selected from the group consisting of hypochlorite, sodium hypochlorite, calcium hypochlorite, iron oxide, metal oxide, calcium ferrate, potassium ferrate, sodium ferrate, oxygen, hydrogen peroxide, peroxide, ozone, chlorine dioxide, and combinations thereof.

4. The method of claim 1, further comprising adding additional acid after the step of adding a second amount of ammonia.

5. The method of claim 1, wherein, after addition of the first amount of ammonia, the mixture is pH 11 or higher.

6. The method of claim 1, wherein the ammonia is aqueous or anhydrous ammonia.

7. The method of claim 1, wherein the dried paste has a pH of between 5.0 and 7.0.

8. The method of claim 1, wherein the concentration of ammonia is at least 20,000 ppm.

9. The method o claim 1, wherein the concentration of ammonia provides a dry weight nitrogen concentration of 6%.

10. The method of claim 1, wherein the concentration of ammonia provides a dry weight nitrogen concentration of 10%.

11. The method of claim 1, wherein the concentration of ammonia provides a dry weight nitrogen concentration of 14%.

12. The method of claim 1, wherein the acid is selected from the group consisting of phosphoric acid, sulfuric acid, sulfamic acid, hydrochloric acid, nitric acid and combinations thereof.

13. The method of claim 1, wherein, after treating with the acid, the paste is pH 7.0 or less.

14. The method of claim 1, further comprising blending a plant nutrient with the thixotropic paste to increase one or more of nitrogen, phosphorus or iron content of the paste.

15. The method of claim 14, wherein the plant nutrient content of the dried paste is at least 8% nitrogen by dry weight.

16. The method of claim 14, wherein the plant nutrient content of the dried paste is at least 12% by dry weight.

17. The method of claim 14, wherein the plant nutrient content of the dried paste is at least 15% by dry weight.

18. The method of claim 1, wherein odor associated with the dried paste is reduced.

19. The method of claim 1, wherein the thixotropic paste is treated with an oxidizing agent such that odorant emission from the dried paste is reduced simultaneously with increasing plant nutrient concentration.

20. The method of claim 1, wherein the extruded paste formed into pellets or granules.

21. The method of claim 20, wherein the pellets or granules are coated.

22. The method of claim 1, further comprising storing the dried paste in a dry environment.

23. The method of claim 1, further comprising applying the dried paste to plants as a fertilizer.

24. The method of claim 1, further comprising applying an antimicrobial stress during any step.

25. The method of claim 24, wherein the microbial stress is selected from the group consisting of a pH greater than pH 10, a pH greater than pH 11.0;

free ammonia concentration in the paste at greater than 1,000 ppm, free ammonia concentration in the paste at greater than 10,000 ppm;

free ammonia concentration in the paste at greater than 15,000 ppm;

heat at greater than 80°

C.;

greater than 100°

C., heat at greater than 121°

C. and combinations thereof.

26. The method of claim 1, further comprising adding a fertilizer to the dried pellets or granules to provide nutrient enhancement.

27. The method of claim 26, wherein the fertilizer is selected lion the group consisting of dry fertilizers, liquid fertilizers, ammonium sulfate, ammonium nitrate, mono-ammonium phosphate, di-ammonium phosphate, urea, urea ammonium nitrate (“

UAN”

), liquid urea, N-P-K fertilizers, 16-4-8, 10-8-8, 6-14-6, and combinations thereof.

28. A method of converting biosolids into fertilizer, comprising:

mixing the biosolids to a homogenous paste;

adding a first amount of ammonia to the homogenous paste to raise the pH of the homogenous paste to above 10.0;

adding an acid to the basic homogenous paste to lower the pH of the basic homogenous paste to below 7.0;

adding second amount of ammonia to the acidic homogenous paste to raise the concentration of free ammonia to above 10,000 ppm; and

adding nutrients to the paste to create the fertilizer.

29. The method of claim 28, further comprising adding additional acid after the step of adding a second amount of ammonia.

30. The method of claim 29, wherein the fertilizer has a final pH of between 5.0 and 7.0.

31. The method of claim 28, further comprising:

adding a granulating agent to the paste;

granulating the paste; and

drying the granulated paste to a dryness of at least 90% of solids.

32. The method of claim 31, wherein the granulated paste is formed into pellets or granules.

33. The method of claim 32, wherein the pellets or granules are coated.

34. The method of claim 28, wherein the biosolids are selected from the group consisting of municipal biosolids and sludges, manures and animal residuals, lagoon sludges, organic-containing sludges produced from food fermentation, sludge waste products, pharmaceutical fermentation waste, industrial fermentation products, and mixtures and combinations thereof.

35. The method of claim 28, wherein the ammonia is aqueous or anhydrous ammonia.