Furnace firing is the biggest single operating expense in
any refinery. Consider a medium-size refinery (250,000 bpd) that consumes
2,000 MMBtu/h. At a cost of $5/MMBtu, thats $87.6 MM/yr
being spent on fuel. A meager improvement of 1% in firing
efficiency would yield $0.876MM/yr in savings and a reduction
in CO2 emissions of 91,600 mtpy.