The gas produced in a coal gasification process is called coal gas, town gas, synthetic gas or syngas. In this report the term syngas will be used. The gasification process occurs as the char reacts with carbon dioxide and steam to produce carbon monoxide and hydrogen which are the main components of syngas. The composition of syngas can significantly vary. Depending on the fuel used in the gasification process and the techniques of process it is possible to have from 5% to 50% of hydrogen in the fuel. The high availability of coal and the possible application of biomass make this an attractive process. Biomass is a durable energy source and the possibility of clean combustion makes it also a clean energy source. The application of biomass is a complex process mainly linked with the capability to maintain a constant quality of the biomass in order to produce a gas with constant properties and compositions. In order to use a gas turbine for the conversion of syngas, the equipment to conduct the process and so the model to develop it should be flexible with respect to changes in fuel quality. The efficiency of the whole process is heavily influenced by the efficiency of the combustion process of syngas. It can be improved through the identification of range of parameters such as pressure, temperature and composition of the fuel, in which the ignition and combustion of syngas is evolving in time compatible with the gas turbine application. Indeed, it is necessary to have tools to analyze the dependencies of the kinetic reaction of syngas from different parameters with a significant level of reliability. In this work a kinetic mechanism of syngas oxidation in order to simulate the combustion of a syngas-air mixtures has been identified and developed. This mechanism allows to investigate the behavior of combustion in a wide range of compositions, pressure and temperature, in particular in the operating conditions of a gas turbine (high pressure and low temperature). In particular the ignition delay of syngas/air mixture in turbogas conditions have been studied. Moreover influence of pressure and CO content on ignition delay has been investigated.
A Comprehensive Kinetic Modeling of Ignition of Syngas/air Mixtures at Low Temperatures and High Pressures
de Joannon M;Sabia P;
2009
Abstract
The gas produced in a coal gasification process is called coal gas, town gas, synthetic gas or syngas. In this report the term syngas will be used. The gasification process occurs as the char reacts with carbon dioxide and steam to produce carbon monoxide and hydrogen which are the main components of syngas. The composition of syngas can significantly vary. Depending on the fuel used in the gasification process and the techniques of process it is possible to have from 5% to 50% of hydrogen in the fuel. The high availability of coal and the possible application of biomass make this an attractive process. Biomass is a durable energy source and the possibility of clean combustion makes it also a clean energy source. The application of biomass is a complex process mainly linked with the capability to maintain a constant quality of the biomass in order to produce a gas with constant properties and compositions. In order to use a gas turbine for the conversion of syngas, the equipment to conduct the process and so the model to develop it should be flexible with respect to changes in fuel quality. The efficiency of the whole process is heavily influenced by the efficiency of the combustion process of syngas. It can be improved through the identification of range of parameters such as pressure, temperature and composition of the fuel, in which the ignition and combustion of syngas is evolving in time compatible with the gas turbine application. Indeed, it is necessary to have tools to analyze the dependencies of the kinetic reaction of syngas from different parameters with a significant level of reliability. In this work a kinetic mechanism of syngas oxidation in order to simulate the combustion of a syngas-air mixtures has been identified and developed. This mechanism allows to investigate the behavior of combustion in a wide range of compositions, pressure and temperature, in particular in the operating conditions of a gas turbine (high pressure and low temperature). In particular the ignition delay of syngas/air mixture in turbogas conditions have been studied. Moreover influence of pressure and CO content on ignition delay has been investigated.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
