Patent ID: 11858823
Assignee: BION ENVIRONMENTAL TECHNOLOGIES, INC.
Field: Chemical engineering (Chemistry)
Classification: CPC C  B  Y | IPC B  C

Claim 15:
16. A process to treat waste containing ammonia nitrogen comprising:
treating waste using anaerobic digestion creating a biogas and a digestate;
treating said biogas to separate and concentrate carbon dioxide in said biogas from other gases in said biogas forming a concentrated carbon dioxide biogas;
treating said digestate at a temperature of at least 80 degrees Celsius to create a gas and, without the addition of chemicals that are not inherently present in the waste, converting substantially all ammonia in the waste to gaseous form in the gas, said gas also containing carbon dioxide and water vapor;
treating said gas from digestion containing gaseous ammonia, carbon dioxide, and water vapor, using partial condensation, or repeated partial condensation, operating at a temperature of at least 80 degrees Celsius, without the use of chemicals that are not inherently present in the waste, to remove from said gas a significant amount of water vapor and organics in liquid condensate form, causing formation of a condenser effluent concentrated gas containing higher concentrations of ammonia gas and carbon dioxide gas than before condensation;
treating said concentrated carbon dioxide biogas and said condenser effluent concentrated gas using absorption or adsorption operating at a temperature of between about 20 and 50 degrees Celsius to form concentrated ammonium carbonate and ammonium bicarbonate;
crystallizing the concentrated ammonium carbonate and ammonium bicarbonate at a temperature of less than about 35 degrees Celsius to form solid ammonium bicarbonate and ammonium carbonate.