Nitrification Denitrification in Intermittent Aeration Process for Swine Wastewater Treatment

• Published in: Journal of environmental engineering (New York, N.Y.) Vol. 127; no. 8; pp. 705 - 711
• Main Authors: Cheng, Jiayang, Liu, Bin
• Format: Journal Article
• Language: English
• Published: Reston, VA American Society of Civil Engineers 01.08.2001
• Subjects: Aeration; Agriculture, rearing and food industries wastes; Ammonia; Anaerobic processes; Anaerobic treatment; Applied sciences; Bacteria; Biological and medical sciences; Biological treatment of waters; Biotechnology; Environment and pollution; Environmental engineering; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Nitrates; Nitrification; Nitrites; Other wastewaters; Pollution; TECHNICAL PAPERS; Wastes; Wastewater; Wastewater treatment; Wastewaters; Water treatment and pollution; Anaerobiosis; Intermittent running; Animal slurry; Nitrogen compounds; Liquid waste; Biological purification; Aeration; Nitrification; Denitrification; Agricultural waste; Waste water purification; Performance; Animal waste; Rearing by-product
• ISSN: 0733-9372; 1943-7870
• DOI: 10.1061/(ASCE)0733-9372(2001)127:8(705)

A continuous-flow intermittent aeration (IA) process has been studied for nitrogen removal from anaerobically digested swine wastewater with high ammonium content. High nitrogen removal efficiency of average 91% total Kjeldahl nitrogen and 92% NH4-N was achieved in an IA system with an alteration of 1-h aeration and 1-h nonaeration. Nitrification and denitrification were found to be responsible for the nitrogen removal in the system. Nitrite and nitrate in the effluent were less than 1.0 mg L and 8.0 mg L, respectively. The specific nitrification and denitrification rates of the single-sludge IA culture were determined through batch experiments as 2.79-3.70 mgNO3-N g volatile suspended solids-h and 0.59-1.03 mgNO3-N g volatile suspended solids-h, respectively. In the IA process, the aeration period created favorable conditions for nitrifying bacteria (dissolved oxygen = 4-6 mg L and oxidation-reduction potential = 80-100 mV), while the nonaeration period provided good environment for denitrifying bacteria (dissolved oxygen < 1 mg L and oxidation-reduction potential as low as 0 mV). Ammonia volatilization in the IA process was negligible (<0.008%). Denitrification activity in the IA process prevented nitrate from accumulation and significant pH change in the system, which is critical for nitrogen removal from swine wastewater with high ammonium content.