Method for oxy-fueled combustion

A combustion method comprising the steps of:

• providing a furnace having a controlled environment, the furnace having substantially no in-leakage from an external environment, and configured to substantially prevent the introduction of air;
• supplying oxygen having a predetermined purity;
• supplying a carbon based fuel;
• feeding the oxygen and the carbon based fuel into the furnace in a stoichiometric proportion to one another;
• limiting an excess of either the oxygen or the carbon based fuel to less than 5 percent over the stoichiometric proportion;
• and
• controlling the combustion of the carbon based fuel to produce a flame temperature in excess of about 4500° F., and to produce an exhaust gas stream from the furnace having substantially zero nitrogen-containing combustion produced gaseous compounds from the oxidizing agent.

A method for operating a furnace comprising the steps of:

• providing a furnace having a combustion region and having a burner, the furnace configured to substantially prevent the introduction of air;
• supplying a carbon based fuel into the combustion region through the burner;
• supplying oxygen at a predetermined purity into the furnace for combustion with the carbon based fuel;
• and
• controlling the combustion of the oxygen and the carbon based fuel to produce a flame temperature of more than about 3000° F. and to produce an exhaust gas stream from the furnace having a temperature of not more than about 1100° F.

A combustion method comprising the steps of:

• providing a furnace having at least one burner, and configured to substantially prevent the introduction of air;
• supplying oxygen at a predetermine purity greater than 21 percent;
• supplying a carbon based fuel;
• feeding the oxygen and the carbon based fuel into the furnace in controlled proportion to each other;
• and
• controlling the combustion of the carbon based fuel to produce a flame temperature in excess of 3000° F.