Denitrification of high-nitrate, high-salinity wastewater

• Published in: Water research (Oxford) Vol. 33; no. 1; pp. 223 - 229
• Main Authors: Glass, Charles, Silverstein, JoAnn
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1999; Elsevier Science
• Subjects: activated sludge acclimation; Applied sciences; Biological and medical sciences; Biological treatment of waters; Biotechnology; denitrification; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; high salinity wastewater; Industrial applications and implications. Economical aspects; industrial wastewater treatment; Industrial wastewaters; ionic strength; nitrate nitrogen; nitrates; Pollution; salinity; sequencing Batch Reactor; wastewater; wastewater treatment; Wastewaters; Water treatment and pollution; activated sludge acclimation; sequencing Batch Reactor; high salinity wastewater; denitrification; industrial wastewater treatment; Activated sludge; Bioreactor; Batchwise; Industrial waste water; Medium effect; Denitrification; pH; Chemical concentration; Waste water purification; Biological purification; Salinity
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/S0043-1354(98)00177-8

Denitrification of a wastewater containing 36,000 mg/L NO 3 − (8,200 mg/L NO 3–N) with ionic strength of 3.0 has been achieved using activated sludge in bench-scale sequencing batch reactors. An activated sludge culture was acclimated to denitrify the wastewater at pH 9, by step-wise increase in wastewater nitrate concentration from 2,700 mg/L NO 3–N to 5,400 mg/L NO 3–N and finally to 8,200 mg/L NO 3–N. Simultaneously, wastewater ionic strength was increased from 0.8 to 2.7 and to 3.0 (5, 16, and 18% total dissolved solids (TDSI). Although complete denitrification occurred, the maximum specific nitrate reduction rate decreased from 50 to 19 mg NO 3–N/g MLSS/h as wastewater nitrate and TDS concentration increased. Also, accumulation of nitrite increased and the maximum nitrite reduction rate decreased. A similar attempt to acclimate activated sludge to denitrify the high-TDS, high-nitrate wastewater at pH 7.5 was unsuccessful.