Process to recover ammonium bicarbonate from wastewater

A process to treat waste containing ammonia nitrogen comprising:

• treating waste in an anaerobic digester creating a digestate;
• treating the digestate using an ultra filter to remove solids of greater than 0.5 micron in size from the digestate;
• heating the filtered digestate to a temperature of at least 80 degrees Celsius and treating the heated, filtered, digestate using a membrane filter device, without addition of chemicals that are not inherently present in the waste, to separate liquid creating a vapor containing water vapor, ammonia, and carbon dioxide;
• cooling the vapor to between 35 and 50 degrees Celsius forming dissolved ammonium carbonate and ammonium bicarbonate in a liquid condensate;
• concentrating the dissolved ammonium carbonate and ammonium bicarbonate to achieve saturation in the liquid condensate using reverse osmosis operating at a temperature between 35 and 50 degrees Celsius;
• and
• crystallizing the concentrated dissolved ammonium carbonate and ammonium bicarbonate condensate at a temperature of less than about 35 degrees Celsius to form solid ammonium bicarbonate and ammonium carbonate.