Response surface optimization, combustion characteristics and kinetic analysis of mixed fuels of Fenton/CaO conditioned municipal sewage sludge and rice husk

The co-combustion characteristics and kinetics of Fenton/CaO conditioned MSS, and biomass rice husk (RH) are studied by thermogravimetry, and the condition optimization was carried out by response surface methodology (RSM). The results show that the mixed fuel with RH is helpful to decrease T-i and T-b values and increase combustion characteristic index (CCI). The CCI of MSS after conditioning is 0.59-0.88 times lower than that of the pure MSS. In addition, the total E-m of S2, MSS/RH mixed combustion after Fenton/CaO conditioning is lower, the combustion reactivity is stronger. According to RSM, the optimum conditions are considered to be: RH mixing ratio 56%, Fenton/CaO conditioner dosage 147 mg g(-1) dry solids, heating rate 30 K min(-1), the maximum CCI 25.3305 x 10(-7)%(2) degrees C-3 min(-2), and the minimum E-m 10.6403 kJ min(-1). This study supplies new insights into combustion technology of sludge.

Automated summary

This study investigated the co-combustion characteristics and kinetics of Fenton/CaO conditioned MSS and biomass rice husk (RH) through thermogravimetry, utilizing response surface methodology for condition optimization. Results showed that mixing with RH can enhance combustion characteristic index (CCI) and reduce combustion temperatures, while improving combustion reactivity. Optimal conditions included RH mixing ratio of 56%, Fenton/CaO conditioner dosage of 147 mg g(-1) dry solids, heating rate of 30 K min(-1), maximum CCI of 25.3305 x 10(-7)%(2) degrees C-3 min(-2), and minimum total E-m of 10.6403 kJ min(-1), providing new insights into sludge combustion technology.