Modeliranje procesa u eksperimentalnoj komori za denitrifikaciju produkata sagorevanja biomase

Abstract

In spite of the many advantages that promote biomass as a renewable energy source, its combustion emits certain pollutants, as any other fuel. Although these negative effects are less pronounced compared to the combustion of fossil fuels, they need to be identified and controlled. The nitrogen oxides (NOx) emission generated from the biomass combustion is one of the key challenges, and their controlling is necessary in order to meet the legal emission limit and to develop high-quality biomass combustion technologies. For a better understanding of the process of NOx reduction, the experimental apparatus was designed for testing of the secondary denitrification techniques at the biomass combustion. This paper provides a description of the experimental installation. Before accessing extensive experiments, it is very useful and important to carry out calculations and initial numerical simulations of processes that need to be in detail experimentally examined. The reactions of selective non-catalytic reduction of nitrogen-monoxide (NO) using ammonia (NH3) as a reagent are analyzed here first. The paper presents the dependence of the reaction rates of reduction and oxidation on the relation between NO and oxygen concentrations in the NH3-SNCR process under conditions of biomass combustion products. In the framework of the preparation of detailed experiments, a comprehensive CFD modeling of complex industrial denitrification processes has been applied, with a comprehensive process analysis including simulation of flow, mixing of components and monitoring of local chemical reactions, taking into account the effects of turbulence on global chemical kinetics.