Performance of an anaerobic baffled reactor and hybrid constructed wetland treating high-strength wastewater in Nepal—A model for DEWATS

Centralized wastewater treatment systems require sophisticated technologies and skilled manpower for their operation and maintenance (O&M). These systems have huge construction as well as O&M costs. Therefore, a Decentralized Wastewater Treatment System (DEWATS) rather than a centralized system might be especially beneficial in developing countries. A model for DEWATS is developed in Nepal with Anaerobic Baffled Reactor (ABR) and hybrid Constructed Wetland (CW). The DEWATS treats high-strength wastewater from 80 households (400 PE). This paper summarizes the performance of the DEWATS from July 2006 to August 2007 in the removal efficiencies of TSS, BOD5, COD, NH4–N, TP and FC. The ABR is very effective in the removal of organic pollutants and could achieve TSS removal up to 91%, BOD5 up to 78% and COD up to 77%. The average removal efficiencies of the DEWATS

[1]  Tony Hoong Fatt Wong,et al.  Hydraulics efficiency of constructed wetlands and ponds , 1999 .

[2]  Peter A. Vanrolleghem,et al.  Constructed wetlands in Flanders: a performance analysis , 2004 .

[3]  J. Vymazal Horizontal sub-surface flow and hybrid constructed wetlands systems for wastewater treatment , 2005 .

[4]  H. Hahn,et al.  Performance of very small wastewater treatment plants with pronounced load variations. , 2007, Water science and technology : a journal of the International Association on Water Pollution Research.

[5]  David C. Stuckey,et al.  The use of the anaerobic baffled reactor (ABR) for wastewater treatment: a review , 1999 .

[6]  J. A. Álvarez,et al.  Anaerobic digesters as a pretreatment for constructed wetlands , 2008 .

[7]  F. Brissaud,et al.  Microphyte and macrophyte-based lagooning in tropical regions. , 2005, Water science and technology : a journal of the International Association on Water Pollution Research.

[8]  R. Shutes,et al.  Reed beds and constructed wetlands for wastewater treatment , 1997 .

[9]  Rafael Mujeriego,et al.  Effect of key design parameters on the efficiency of horizontal subsurface flow constructed wetlands , 2005 .

[10]  W Green,et al.  Small scale sanitation technologies. , 2005, Water science and technology : a journal of the International Association on Water Pollution Research.

[11]  Jan Vymazal,et al.  The use of sub-surface constructed wetlands for wastewater treatment in the Czech Republic: 10 years experience , 2002 .

[12]  H. D. Stensel,et al.  Wastewater Engineering: Treatment and Reuse , 2002 .

[13]  Hans Brix,et al.  The use of vertical flow constructed wetlands for on-site treatment of domestic wastewater: New Danish guidelines , 2005 .

[15]  F. Brissaud,et al.  Mosquito development and biological control in a macrophyte-based wastewater treatment plant. , 2005, Water science and technology : a journal of the International Association on Water Pollution Research.

[16]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[17]  Manuel Soto,et al.  Performance of an anaerobic digester-constructed wetland system for a small community , 2008 .

[18]  S. Pillay,et al.  The anaerobic baffled reactor (ABR): An appropriate technology for on-site sanitation , 2007 .

[19]  Jaume Puigagut,et al.  Subsurface-flow constructed wetlands in Spain for the sanitation of small communities: A comparative study , 2007 .

[20]  F Brissaud,et al.  Low technology systems for wastewater treatment: perspectives. , 2007, Water science and technology : a journal of the International Association on Water Pollution Research.