Self‐Desulphurization and Self‐Denitrification Properties and Mechanisms in Biobriquette Combustion

Abstract

AbstractTo control pollutant emissions from the combustion of both domestic stoves and small‐capacity industrial boilers, a new artificial solid fuel called biobriquette with self‐denitrification and self‐desulphurization has been developed. It is manufactured from a mixture of coal, biomass (agricultural wastes, cornstalk, etc.), desulphurizer and denitrificator such as limestone, seashell and pulp black liquid (industrial wastes) under a high compression pressure. In this study, the experiments of briquetting, pyrolysis and combustion were performed in order to reveal its characteristics of briquetting, self‐denitrification and self‐desulphurization.The main results are that pulp black liquid and/or biomass improves the briquetting and combustion of biobriquette. The seashell called scallop has high desulphurization efficiency, but they only slightly reduce NOx emissions in biobriquette combustion. The pulp black liquid mixed in the biobriquette has not only a good desulphurization but also significant denitrification result. The denitrification reaction happens mainly in the char combustion stage and slightly in the volatile combustion stage. The denitrification efficiency of about 40% can be obtained when the mixture reaches 10 mass%. The main mechanism of denitrification was considered to originate from NH3 and NaOH included in the pulp black liquid.