Combustion characteristics of co-combusted municipal solid wastes and sewage sludge

ABSTRACT

Incineration is an effective way to manage and utilize sewage sludge (SS). In this study, thermogravimetric analysis and infrared spectroscopy were used to study the characteristics of co-combusted municipal solid wastes (MSW) and SS, as well as the pollutant emission characteristics. Positive interaction was found in the co-combustion. Combustion characteristic index increased from 1.71 × 10⁻⁶ min⁻²°C⁻³ to 1.73 × 10⁻⁶ min⁻²°C⁻³ when the mass fraction of SS increased from 0% to 10%. Activation energy decreased as the proportion of sludge increased. Activation energy of the main reaction stage of MSW and SS was 321.12 KJ/mol and 63.15 KJ/mol, respectively. The emission of HCl and NO decreased during co-combustion. Considering combustion intensity, activation energy, and pollutant emission, 10% SS was the optimal blend. CaCO₃, CaO, Ca(OH)₂, or natural limestone decreased the emission of HCl and NO, and decreased the activation energy in the first stage but increased it in the second stage.

KEYWORDS:

• Calcium-based absorbents
• co-combustion
• combustion characteristics
• municipal solid wastes
• sewage sludge

Additional information

Funding

This work was supported by Guangzhou Science and Technology Program key projects [201804020082], Guangdong Key Laboratory of Efficient and Clean Energy Utilization, South China University of technology [2013A061401005], General Administration of Quality Supervision, State Administration for Market Regulation Science and Technology Project (No. 2017QK152).

Notes on contributors

Limei Chen

Limei Chen obtained Bachelor degree in Thermal Energy and Power Engineering from South China University of Technology in 2016. She is currently a doctoral candidate in South China University of Technology. Her research interests are efficient and clean utilize of energy.

Yanfen Liao

Yanfen Liao obtained Ph.D. degree in Engineering Thermophysics from Zhejiang University in 2003. She is currently professor and doctoral supervisor at South China University of Technology. Her research interests are efficient and clean utilize of energy.

Yuqing Xia

Yuqing Xia obtained Bachelor degree in Energy and Power Engineering from South China University of Technology in 2018. He is currently a Master degree candidate in south China University of Technology. His research interests are efficient and clean utilize of energy.

Xiaoqian Ma

Xiaoqian Ma obtained Ph.D. degree from Huazhong University of Technology in 1995. He is currently professor and doctoral supervisor at South China University of Technology. His research interests are efficient and clean utilize of energy.