Open AccessNutrient Removal Performance on Domestic Wastewater Treatment Plants (Full Scale System) between Tropical Humid and Cold Climates
Author(s) -
Pongsak Noophan,
Rawiwan Rodpho,
Pimook Sonmee,
Martha Hahn,
Suthep Sirivitayaphakorn
Publication year - 2018
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.16
H-Index - 2
ISSN - 2287-075X
DOI - 10.35762/aer.2018.40.2.3
Subject(s) - denitrifying bacteria , wastewater , effluent , sewage treatment , nitrification , biochemical oxygen demand , environmental science , nutrient , organic matter , denitrification , activated sludge , nitrate , phosphorus , environmental engineering , chemical oxygen demand , environmental chemistry , waste management , nitrogen , ecology , chemistry , biology , engineering , organic chemistry
Two full scale systems of oxidation ditches for domestic wastewater treatment plants (WWTP) were used as study sites: Phuket Province, southern Thailand (representative of tropical humid climates) and Plum Creek, Castle Rock, Colorado, USA (representative of cold climates). The treatment systems at both sites were designed for biological nutrient removal (BNR) fromextended activated sludge. Nitrogen is removed by nitrification-denitrification processes. The solid retention time (SRT) for both treatment plants was ≥ 10 das recommended by theory for complete nitrification in activated sludge wastewater treatment plants. Influents and effluents from these sites were compared in respect to flow rate, biochemical oxygen demand (BOD), organic nitrogen, ammonium, nitrate, total nitrogen, and phosphorus concentrations. At both sites, nutrient removal reached more than 75% because there was sufficient carbon for denitrifying and phosphate accumulating organisms. Furthermore, low dissolved oxygen concentration, long SRT, and hightemperature could be key factors to promote activity of some groups of bacteria in consuming organic matter and nutrients in wastewater in warm climates. For this reason, plant design and operating procedures for wastewater treatment in cold climates might not be always be applicable to warm climates.