Community Wastewater Treatment with Attached Growth Assisted Constructed Wetland Reactor

Abstract

Constructed wetlands are systems of artificial wastewater treatment which consists of shallow ponds or channels that have been planted with aquatic plants. The treatment is based on the natural, biological, physical and chemical treatment of wastewater. The technique is reported to be cost effective as compared to other methods. The constructed wetlands have impermeable clay or synthetic coatings and artificial structures for controlling the direction of flow, liquid retention time and the water level. However, there are certain limitations of constructed wetland system, which need improvement for its wide adoptability. As such the effort was made to assist the constructed wetland system with attached growth system with the aim to design an economical and user friendly waste water treatment option for the small community. The laboratory scale model was fabricated using GI sheet of thickness 0.5 mm. The overall capacity of the model was 275 L. The laboratory scale reactor model consisted of four compartments out of which first three compartments were based on attached growth system and the fourth compartment acted as constructed wetland reactor. All the three compartments were packed with different types of artificial, semi-artificial and natural media. The fourth compartment consisted of media packed from bottom as aerocon stone layers 03 in numbers followed by snail shell, followed by a soil layer of 80 mm thick which holds the plants in rows. The reactor was operated as continuous flow reactor with varying detention time and change of different type of media packed in the reactor. The performance of Customized Constructed Wetland reactor was observed under various operating conditions for removal of BOD, COD and TS parameters. The paper presents the details regarding the development of the reactor model, operation of the reactor model and results obtained during the course of study. The paper also cover the discussion regarding the improved performance of reactor noted during the study and adoptability of the developed reactor model for community waste treatment.