Enhancing combustion with variable composition process gas

摘要

Method and apparatus for enhancing the combustion of a process gas of variable composition which gas is used for steam generation in producing heavy oil. The mass flow of the process gas containing hydrocarbons, carbon dioxide and water is measured. It is assumed that the process gas is saturated with water vapor and the water content of the process gas is then obtained. The content of carbon dioxide in the process gas is nominally obtained with an oxygen analyser measuring the flue gas from a steam generator thereby giving a close approximation of hydrocarbon content and allowing an expedited calculation of the energy content and air required. The nominal carbon dioxide value is compared with the calculated carbon dioxide value based on the actual flow of process gas and purchase gas and the oxygen content so that the quantity of carbon dioxide is approximated. If increased flow of the process gas is required, changes in the flow of the introduced air can be quickly made without relying exclusively on oxygen analysis of the exhaust gas from the steam generation process. Steam of a desired energy content and quantity for well injection purposes may also be produced.