Process and system for recovering hydrocarbons from underground formations

摘要

A gas generator for use in a borehole for generating steam and other hot gases for use in recovering hydrocarbons or other fluids from underground formations. The gas generator comprises a housing forming a chamber with a combustion zone at one end and a restricted outlet at the other end. A second zone is located downstream of the combustion zone and a gas and water mixing zone is located between the second zone and the restricted outlet. The generator has a cooling annulus surrounding the chamber with passages leading from the annulus to the gas and water mixing zones. Methane is burned in the combustion zone with just enough oxygen to maintain the flame temperature below the decomposition temperature of methane to convert substantially all of the carbon to carbon monoxide and to form hydrogen. In the second zone, the carbon monoxide and hydrogen are burned with an additional supply of oxygen to increase the temperature and to form carbon dioxide and hydrogen. Water is supplied to the annulus for cooling purposes and for injection into the gas and water mixing zone for cooling the gases therein and for forming steam whereby hydrogen, steam, and carbon dioxide are injected from the restricted outlet.