US 4,199,024 A · Multistage gas generator

Abstract

A multistage gas generator for use in a borehole for recovering hydrocarbons from the subsurface formations. The gas generator has an upper end and a lower restricted outlet. A pilot stage is located at the upper end and a plurality of spaced apart intermediate stages are located between the pilot stage and the lower restricted outlet. Hydrogen and oxygen are fed to the pilot stage for ignition. Oxygen is fed to a first intermediate stage and hydrogen and oxygen are fed to each of the other intermediate stages for injection into the gas generator. Excess hydrogen from the pilot stage is burned in the zone of the first intermediate stage and hydrogen and oxygen of each succeeding stage is ignited by the preceeding stage. Water for cooling purposes also is fed to each intermediate stage. Downhole valves selectively controllable from the surface are provided for the pilot stage and each of the intermediate stages. These valves allow the intermediate stages to be selectively operated to increase or decrease the BTU output or to vary other characteristics of the output.

Claims14

Dependent claims

A system for recovering hydrocarbons or other materials from underground formations penetrated by a borehole comprising:

a gas generator including,
means defining a main chamber having an upper end and a lower outlet for the passage of heated gases,
a pilot stage disposed at the upper end of said gas generator and including a pilot chamber having a restricted outlet communicating with said main chamber,
a plurality of spaced apart intermediate stages located between said pilot stage and said lower outlet,
a predetermined number of said plurality of intermediate stages including fuel and oxidizing fluid nozzles communicating with said main chamber,
means adapting said gas generator for insertion into a borehole to a level adjacent underground formations penetrated thereby;
means for supplying fuel and an oxidizing fluid to said pilot chamber for ignition therein;
and,
means for supplying fuel and an oxidizing fluid to each of said predetermined number of said intermediate stages for injection into said main chamber through the fuel and oxidizing fluid nozzles, respectively, for ignition at a plurality of spaced apart zones.

6 more elements

A system for recovering hydrocarbons or other materials from underground formations penetrated by a borehole comprising:

a gas generator including,
means defining a main chamber having an upper end and a lower outlet for the passage of heated gases,
a pilot stage disposed at the upper end of said gas generator and including a pilot chamber having a restricted outlet communicating with said main chamber,
a plurality of spaced apart intermediate stages disposed between said pilot stage and said lower outlet,
a predetermined number of said plurality of intermediate stages comprising a fuel nozzle, an oxidizing fluid nozzle and a water nozzle, communicating with said main chamber,
means adapting said gas generator for insertion into a borehole to a level adjacent underground formations penetrating thereby;
means for supplying fuel and an oxidizing fluid to said pilot chamber for ignition therein;
means for supplying fuel and an oxidizing fluid to each of said predetermined number of said intermediate stages for injection into said main chamber through the fuel and oxidizing fluid nozzles, respectively, for ignition at a plurality of spaced apart zones;
and
means for supplying water to each of said water nozzles of said predetermined number of said intermediate stages for injection into said main chamber.

7 more elements

Dependencies are inferred from the claim text.

Multistage gas generator

Life of this patent

Multistage gas generator

Life of this patent

Abstract

Claims14