Research on the Influence of Combustion Methods on NO_x Emissions from Co-combustion of Various Tannery Wastes

Abstract

To further increase combustion efficiency and reduce nitrogen oxide pollution caused by tannery wastes, three raw materials, including tannery sludge, chrome-tanned buffing dust, and chrome shavings, were burned together in a dual-bed model reactor under various conditions. In addition, a thermogravimetric analysis of co-combustion of three tannery wastes was studied in this study, which was conducive to understanding the combustion characteristics and positive effects. The comprehensive combustibility index S, the flammability index K r, and the stable combustion characteristic index G b all increased when the tannery sludge was blended with chrome-tanned buffing dust and chrome shavings, indicating that the combustion behavior was improved by co-combustion. For normal combustion, decreasing the gas volume flow and temperature resulted in a decrease in the oxidation of nitrogen compounds, consequently lowering the NO x emission. During air staged combustion, at an appropriate secondary gas ratio of about 10–40%, the NO x reduction would be increased from 10.9 to 19.3%. By increasing the tertiary gas volume flow from 0.2 to 1.1 L/min in decoupling combustion, an average relative NO x reduction efficiency of 47% was attained compared with normal combustion. The results offered a viable technology that resulted in a lower NO x emission and realized the application of decoupling combustion.

Numerical simulation on influencing factors of co-firing of municipal solid waste and leather

“…As an industrial waste, leather has a high organic matter content, and its direct combustion will cause serious pollution to the environment; therefore, the sustainable treatment of industrial waste is particularly important (Muralidharan et al 2022). Zhang et al (2022) studied the co-combustion process of tannery waste and found that parameters such as integrated combustion index and stable combustion characteristics index were increased, which indicated that effective combustion was achieved through co-combustion. Kluska et al (2020) studied the co-combustion of pelletized leather tannery waste and hardwood pellets on a grate.…”

State-of-the-Art and Recent Advances in the Abatement of Gaseous Pollutants from Waste-to-Energy

“…Urea can also be applied in its pure, solid form. Two processes are important for the removal of nitrogen from flue gases: SNCR and SCR [45].…”