Method for producing ammonia or ammonium by fermentation

Abstract

The invention provides a process for producing ammonia or ammonium from an organic material, the method by contacting the organic material with at least one hydrolytic enzyme, in a medium, to produce a medium including hydrolyzed or partially hydrolyzed organic material suitable for microbial fermentation. The hydrolyzed or partially hydrolyzed medium with organic material is then fermented in the presence of at least one microorganism capable of ammonification, wherein the fermenting is under conditions, and for a sufficient period of time, to produce a fermentation product that comprises ammonia or ammonium. The organic material includes nitrogenous compounds suitable for conversion to ammonia or ammonium.

What is claimed is: 
     
         1 . A process for producing ammonia or ammonium from an organic material, the method comprising:
 (a) contacting the organic material with at least one hydrolytic enzyme, to produce medium comprising hydrolyzed or partially hydrolyzed organic material suitable for microbial fermentation,   (b) fermenting the medium comprising hydrolyzed or partially hydrolyzed organic material in the presence of at least one microorganism capable of ammonification, wherein the fermenting is under conditions, and for a sufficient period of time, to produce a fermentation product that comprises ammonia or ammonium;   wherein the organic material comprises nitrogenous compounds such as amines and/or proteins suitable for conversion to ammonia or ammonium.   
     
     
         2 . The process of  claim 1 , wherein the medium of step (b) is enriched with a carbohydrate suitable for promoting microbial growth. 
     
     
         3 . The process of  claim 1 , wherein at least one microorganism is a bacterium selected from the group consisting of a genus of  Aeromonas, Citrobacter, Clostridium, Bacillus, Enterobacter, Enterococcus, Klebsiella, Pseudomonas  and  Staphylococcus.    
     
     
         4 . The process of  claim 3 , wherein the bacteria is selected from the group consisting of  Clostridium perfringens, Clostridium beijerinckii  or  Clostridium butyricum  or a combination thereof. 
     
     
         5 . The process of  claim 3 , wherein the bacteria is an isolate deposited as VTT-E-123272 or is an isolate deposited as VTT-E-123273. 
     
     
         6 . The process of  claim 1 , wherein the hydrolytic enzyme is selected from the group consisting of an amylase, cellulase, protease, phytase and combinations thereof. 
     
     
         7 . The process of  claim 1 , wherein the hydrolytic enzyme is selected from the group consisting of Alcalase®,  Aspergillus oryzae  acidic protease,  Aspergillus oryzae  alkaline protease,  Bacillus clausil  protease,  Bacillus lentus protease, Bacillus stearothemophilis  protease,  Bacillus subtillus  protease, bromelain, collagenase type 2, Flavourzyme® protease mix from  Aspergillus oryzae , papain, pepsin, proteinase K, porcine pancrease trypsin and combinations thereof. 
     
     
         8 . The process of  claim 1 , wherein the hydrolytic enzyme is a Flavourzyme® present in the medium in a concentration of about 300 mU through about 40,000 mU. 
     
     
         9 . The process of  claim 1 , further comprising recovering ammonia or ammonium from the fermentation product. 
     
     
         10 . The process of  claim 9 , wherein the ammonia or ammonium is recovered by the steps of:
 (a) dehydrating the fermentation product to provide a dry fermentation product;   (b) collecting ammonia or ammonium-water or gas mixture released during the dehydrating step (a); and   (c) recovering the ammonia or ammonium   (d) converting the recovered ammonia or ammonium to a unified form; and   (e) recovering the unified form;   wherein the unified form is selected from the group consisting of: ammonium nitrate, ammonium sulphate, ammonium chloride, ammonium phosphate, diammonium phosphate and monoammonium phosphate and combinations thereof.   
     
     
         11 . The process of  claim 1 , wherein the organic material is selected from the group consisting of meat-and bone meal (MBM), feather meal, slaughterhouse waste, whey, municipal waste, fish meal, beet root, legumes, fruit, food industry waste streams, sugar industry waste streams and combinations thereof. 
     
     
         12 . The process of  claim 1 , wherein the fermenting step is conducted at a pH ranging from about pH 2 to about pH 14 and at a temperature ranging from about 20° C. to about 70° C., or preferably wherein the fermenting step is conducted at a pH ranging from about pH 6.0 to about pH 9.0, and at a temperature ranging from about 30° C. to about 45° C. 
     
     
         13 . The process of  claim 1 , wherein the hydrolysis step is conducted at a pH ranging from about pH 2 to about pH 14, and at a temperature ranging from about 20° C. to about 80° C. or preferably wherein the hydrolysis step is conducted at a pH ranging from about pH 5 through about pH 9, and at a temperature ranging from about 45° C. through about 60° C. 
     
     
         14 . A fermentation product produced by the process of  claim 1 . 
     
     
         15 . A  Clostridium  bacterial strain deposited as VTT-E-123272 or a  Clostridium  bacterial strain deposited as VTT-E-123273.