Details

Autor(en) / Beteiligte

• Yin, Fang-Fang
• Guo, Hui-Fang

Titel

Influence of additional methanol on both pre- and post-denitrification processes in treating municipal wastewater

Ist Teil von

• Water science and technology, 2022-03, Vol.85 (5), p.1434-1443

Ort / Verlag

England: IWA Publishing

Erscheinungsjahr

2022

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Changes in functional properties of biological denitrification in the long-term use of methanol were explored in both pre- and post-denitrification processes. The two systems employed were sequencing batch reactor (SBR) using post-denitrification in temporal sequence, and Carrousel oxidation ditch, which was equipped with a separate pre-denitrification zone. In the SBR, stable nitrate reduction rates reached after 37 days elapsed with addition of methanol (TOC/N = 1.4-1.8) at the start of anoxic phase, and specific denitrification rate increased from 0.378 mgNO -N·(gVSS·h) to 2.406 mgNO -N·(gVSS·h) . Besides, by means of nitrogen uptake rate (NUR) batch tests based on methanol-adapted sludge, the appropriate range of TOC/N ratios for complete denitrification was estimated to be 1.10-2.68. By comparison, the Carrousel oxidation ditch that was fed with methanol in the anaerobic zone took fewer days (29 days) to obtain a constant effluent nitrate. Moreover, the denitrification yield in ditch was elevated from an initial value of 0.082 mgTN/mgCOD to 0.123 mgTN/mgCOD, and the nitrogen removal efficiency reached up to a level of 68%. The focus on denitrification potential with external methanol is valuable to provide information for developing carbon dosage control, as well as predict the nitrate effluent quality of the plant.