Exhaust stack for glass melter

An exhaust stack for a submerged combustion melter, the exhaust stack comprising:

• a lower flue that includes a circumferential shell having an interior surface that defines an exhaust flow passage of the lower flue, the circumferential shell of the lower flue also defining an internal cooling passage configured to circulate a coolant through the circumferential shell of the lower flue;
• an upper flue that includes a circumferential shell having an interior surface that defines and exhaust flow passage of the upper flue, the circumferential shell of the upper flue also defining an internal cooling passage configured to circulate a coolant through the circumferential shell of the upper flue;
• an expansion joint disposed between the lower flue and the upper flue and which compliantly couples the lower flue and the upper flue together;
• a hood coupled to the upper flue and that includes a circumferential shell, the circumferential shell of the hood having an interior refractory liner that defines an exhaust flow passage of the hood, wherein the circumferential shell of the hood defines one or more dilution inlets, and wherein each of the one or more dilution inlets extends through the circumferential shell of the hood to the exhaust flow passage of the hood.

A method of cooling an exhaust material exiting a submerged combustion melter, the method comprising:

• discharging combustion products from one or more submerged combustion burners directly into a glass melt contained within an interior of a tank of a submerged combustion melter to heat and agitate the glass melt;
• directing an exhaust material generated within the interior of the tank through an exhaust outlet of the tank and flowing the exhaust material through an exhaust stack that is connected to the tank of the submerged combustion melter, the exhaust stack comprising a lower flue coupled to the tank and in fluid communication with the exhaust outlet, an upper flue in fluid communication with the lower flue, and a hood in fluid communication with the upper flue;
• cooling the exhaust material in the lower flue with a coolant that circulates within an internal cooling passage of the lower flue and/or by spraying a cooling fluid directly into the exhaust material as the exhaust material flows through the lower flue;
• cooling the exhaust material in the upper flue with a coolant that circulates within an internal cooling passage of the upper flue and/or by spraying a cooling fluid directly into the exhaust material as the exhaust material flows through the upper flue;
• cooling the exhaust material in the hood by directly mixing a diluent into the exhaust material as the exhaust material flows through the hood;
• and
• flowing the exhaust material out of the hood, through a hood outlet, and downstream of the exhaust stack.