Research on co-combustion behavior of sewage sludge and coal slime

Abstract

The treatment of the large amount of coal slime and municipal sewage sludge in Shanxi Province and even the country is facing unprecedented challenges. Clean combustion technology is the preferred method for sewage sludge-coal slime co-processing. In order to explore the interaction of sludge - coal mud combustion, provide a basis for cleaning and efficient combustion utilization. This paper uses thermal heavy mass spectral (TG-MS) to study the precipitation characteristics of combustion characteristics and pollutant gas products (CH4, CO, CO2, NH3, HCN, NO, NO2, H2S, CH3SH, COS, SO2, CS2, SO3), in the combustion and coal burning process in sludge and coal mud. At the same time, the Coats-Redfern Integral Law is used to dynamically explore the mid-combustion process of sludge and coal mud alone. The results show that there is a significant interaction in the process of coal burning in sludge and coal mud. Sludge and coal mud promote each other, improve the overall reaction performance, in which the combustion characteristics are optimal when the coal slime is blended 20%. It indicates that the increase in sludge ratio does not affect the combustion performance of the fuel overall. The Em of sludge and coal slime were 51.170 kJ/mol and 78.538 kJ/mol, sludge can reduce the average activation energy of the mixed sample, and the actual Em of the mixed sample is lower than the calculation. The kinetic model is (D3→D4) when the sludge is alone; the combustion kinetic model (F1) when the coal slime is separate, and the interval kinetic model of the mixed sample is (D3→D1→D3/F1), indicating interaction the reaction mechanism during the combustion can be changed. When the coal slime is blended 20%, the inhibition of the greenhouse body (319.742%) is preferably inhibited; when the coal slime is blended 80%, the difference (636.492%) and the inhibitory inhibition containing traditional (534.811%); indicating interaction is a great inhibitory effect on the traditional form of integrated varieties, in which the inhibitory effect of the contaminant contaminated body content is most (319.740%) when the coal slime is blended 20%.

Keywords

• sewage sludge
• coal slime
• tg-ms
• combustion characteristics
• co-combusion
• clean combusion