Convection Recuperators

Convection recuperators (also referred to as "flue" or "canal" recuperators) are tubular heat exchangers that utilize convection heat transfer to preheat combustion air or gas for the purpose of saving fuel. By recovering heat from the hot waste gas exiting a furnace and transferring it to the combustion air feeding the burners, fuel usage can be reduced by an average of twenty-five percent (25%), and in many cases, greater savings are realized. Waste gas temperatures entering convection recuperators are usually in the 1500°F to 2000°F range, and combustion air preheat temperatures are usually in the 800°F to 1200°F range.

Convection recuperators are comprised of tube bundles with the tubes welded to the tube sheets to assure gas tightness. Tube arrangement, tube material and flow pattern are based on the specifics of each individual application, including temperatures, compositions, pressure drop limits and space availability. In a typical design, the hot waste gas from the furnace flows horizontally through the recuperator, passing outside of vertical tubes. Combustion air en route to the burners makes two or more passes inside the tubes in a counter cross-flow pattern.

Steel soaking pits Steel reheat furnaces Steel heat treat furnaces Steel anneal and pickle lines Steel galvanizing lines Direct reduced iron furnaces Aluminum melting furnaces Aluminum de-lacquering systems Aluminum heat treat furnaces Ceramic and refractory kilns Thermal oxidizers Waste incinerators