Aerobic in-vessel co-composting of dewatered sewage sludge with mixed municipal wastes under subhumid and semiarid atmospheric conditions

ABSTRACT

Recent trends in fecal sludge management evoke the need for improving facilities for co-composting with municipal wastes having spatiotemporally varying compositions under changing atmospheric conditions. The present study is an attempt to recognize the need for locating an aerobic in-vessel co-compost unit in the vicinity of an overloaded sewage treatment plant aiming at synergistic waste management through minimizing water and land resources requirement. Dewatered sewage sludge was incorporated at selected proportions to differently degradable wastes under semiarid and subhumid conditions. The results indicate that the prevailing atmospheric conditions elongated the spray cover from surface aerators in the downwind direction, enabling the compost to receive augmented moisture supply with susceptible aerobic organisms towards achieving faster stability within 35 days. The results also suggest that temporal redistribution of nitrogenous compounds, as well as reduced emission of volatile organics, generally followed the proportion of partially digested sludge in the mixture. The study emphasizes the suitability of combined sludge dewatering and composting system for promoting sustainable and integrated waste management without adverse environmental impacts.

KEYWORDS:

• Aerobic composting
• atmospheric conditions
• co-composting
• dewatered sewage sludge
• municipal solid waste

Acknowledgments

The authors would like to acknowledge the support rendered by the management and staff of Bannari Amman Institute of Technology, Sathyamangalam.

Additional information

Funding

This research was funded by Science and Engineering Research Board, Department of Science and Technology, Government of India under Swacch Bharat Mission [ECR/2016/001114/ES].

Notes on contributors

M Vasudevan

M Vasudevan is working as Assistant Professor in the Department of Civil Engineering at Bannari Amman Institute of Technology Sathyamangalam, Tamil Nadu, India. He obtained PhD in Environmental (Civil) Engineering from Indian Institute of Technology Madras in 2015. He works in the area of sustainable waste management, clean technology, groundwater contamination assessment and modeling.

K Karthika

K Karthika obtained her UG in Civil Engineering from Bannari Amman Institute of Technology Sathyamangalam, Tamil Nadu, India in 2018. Her UG main project was on this topic.

S Gowthaman

S Gowthaman obtained his UG in Civil Engineering from Bannari Amman Institute of Technology Sathyamangalam, Tamil Nadu, India in 2018. His UG main project was on this topic.

K Karthick

K Karthick obtained his PhD in Environmental Science from Bharathiar University, Tamil Nadu, India in 2016. He works in the area of water and wastewater treatment, adsorption and nanotechnology for water treatment.

P Balaganesh

P Balaganesh is working as a research scholar at Bannari Amman Institute of Technology Sathyamangalam, Tamil Nadu, India. His areas of interest include wastewater treatment and bioenergy conversion.

S M Suneeeth Kumar

S M Suneeeth Kumar is working as Professor in the Department of Civil Engineering at Bannari Amman Institute of Technology Sathyamangalam, Tamil Nadu, India. He obtained PhD in Environmental (Chemical) Engineering from Indian Institute of Technology Kanpur in 1998. His areas of interest include environmental engineering and water supply and infrastructure.

N Natarajan

N Natarajan is working as Associate Professor in the Department of Civil Engineering at Dr. Mahalingam College of Engineering and Technology, Pollachi, Tamil Nadu, India. He obtained PhD in Water Resources (Civil) Engineering from Indian Institute of Technology Madras in 2012. We works in the area of environmental modeling and assessment, clean technology, groundwater contamination assessment and modeling.