Performance of Canna Indica based microscale vertical flow constructed wetland under tropical conditions for domestic wastewater treatment

Abstract

Constructed wetlands (CWs) have great potential as low-cost natural wastewater treatment in developing countries. The present study appraises the performance of the vertical flow constructed wetland for domestic wastewater treatment. More specifically, the potential of Canna Indica in the removal of carbon, nitrogen, and phosphorus (CNP) from wastewater under tropical conditions. CW cell was fabricated with a vegetative layer of Canna Indica and tested with domestic wastewater. Based on the test results, Canna Indica shows a high Removal Efficiency (RE) of Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD₅) on the order of 87% and 91%, respectively. Similarly, nutrients removal efficiency for total nitrogen (TN), total phosphorus (TP) was found to be 97% and 98%, respectively. The investigation also revealed that there is considerable removal of sulfates with efficiency equal to 78.4%. Overall, the Canna Indica based CWs were found to be suitable for wastewater treatment in the tropical regions, provided a viable medium for treating the wastewater in peri-urban and rural areas of developing countries.

Novelty statement

This study investigates the performance of Canna indica based vertical flow wetlands for greywater treatment. The study investigates the results at different hydraulic retention times and loading rates.

There are no much studies reporting the performance of this variety of plant species under a tropical humid climate.

The results from the study can encourage adoption of this plant variety, indigenous to this part of the country, for wastewater treatment

Highlights

• It could emphasize the importance of familiarity with constructed wetlands to comprehend the RE of various climatic zones.

• It is possible to highlight the Canna-based CW's efficiency in removing organics and nutrients from domestic wastewater.

• The possibility for field-scale Canna-based CW to remove pollution in tropical climates was investigated, and

• Decentralization of wastewater treatment at the household level to apply CWs that will improve wastewater quality.

Keywords:

• Constructed wetlands
• trophical climate
• Canna indica species

Acknowledgment

Dr. RM gratefully acknowledges the funding support from Water Technology Initiative, Department of Science and Technology, Government of India through the project DST/DD/TM/WTI/2k17/0079.