Apparatus and method for progressive reduction of flue gas

A method for reducing pressure of a flue gas, said method comprising:

• providing an apparatus comprising:
• an orifice chamber having:
• an inlet pipe for receiving the flue gas;
• a flow region defined downstream of an exit of the inlet pipe and having at least a first section and a second section, the first section defined downstream of the inlet pipe and the second section defined downstream of the first section;
• and
• an outlet pipe to disperse a pressure reduced flue gas;
• wherein the first section having a flow developer means and at least one auxiliary orifice plate;
• and
• wherein the second section having a plurality of orifice plates spaced apart along a flow length of the second section.
• the method further comprising:
• introducing the flue gas into the inlet pipe of the orifice chamber;
• achieving progressive reduction of pressure of the flue gas between successive orifice plates including the at least one auxiliary orifice plate of the first section and the plurality of orifice plates of the second section;
• and
• dispersing the pressure reduced flue gas through the outlet pipe.