Mono-fermentation of chicken manure: Ammonia inhibition and recirculation of the digestate

• Published in: Bioresource technology Vol. 178; pp. 238 - 246
• Main Authors: Nie, Hong, Jacobi, H. Fabian, Strach, Katrin, Xu, Chunming, Zhou, Hongjun, Liebetrau, Jan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-02-2015
• Subjects: Ammonia; Ammonia - pharmacology; Ammonia inhibition; Ammonia stripping; Animals; Batch Cell Culture Techniques; Bioreactors; Chicken manure; Chickens; Continuously stirred tank reactors; Fatty Acids, Volatile - analysis; Fermentation; Hydrogen-Ion Concentration; Inhibition; Liquids; Manure; Manure - analysis; Nitrogen - analysis; Recycled; Stripping; Tanks; Time Factors; Volatilization; Waste Products; Ammonia stripping; Chicken manure; Fermentation; Ammonia inhibition
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2014.09.029

•Mono-fermentation of chicken manure was performed for several hundred days.•Controlled recirculation of ammonia stripped fermenter-liquid was applied.•Ammonia-levels during fermentation were steadily controlled.•Stable process was performed at levels of total ammonia nitrogen of above 6g/L.
The effects of ammonia concentration on the performance and stability of mono-fermentation of chicken manure were investigated in a lab-scale continuous stirred tank reactor at 40°C. Technical stripping was performed to remove ammonia from the liquid fraction of digestate, and the entire product was recycled to the fermenter to control ammonia concentration in the fermenter. Organic loading rate (OLR) of 5.3gVS/(Ld) was achieved with an average free ammonia nitrogen (FAN) concentration of 0.77g/L and a specific gas yield of 0.39L/gVS. When OLR was increased to 6.0gVS/(Ld), stable operation could be obtained with an average FAN concentration of 0.86g/L and a specific gas yield of 0.27L/gVS. Mono-fermentation of chicken manure was successfully carried out at high ammonia concentrations. Controlled recirculation of treated liquid fraction of digestate could be a solution in large-scale application for both: to avoid ammonia inhibition and minimize digestate.