Burners individual ratio controls

Individual ratio controls at every burner make it easy to modify the input profile pattern up and down or across a furnace without having to reset the ratio of each burner afterward. 

Burners. If at all possible, burners should have individual air/fuel ratio controls, with air primary, that is, air adjusted by heat demand (temperature), and fuel adjusted to follow air flow changes. If the air/fuel ratio control is fuel primary, the furnace might be accidentally filled with a rich mixture—a condition that is difficult to correct without crossing the explosive limit of the fuel. There should be a quick-shutoff fuel valve (reachable without a ladder) at the nearest exit. 

Carbon Monoxide Carbon monoxide is a key intermediate in the oxidation of all hydrocarbons. In a well-adjusted combustion system, essentially all the CO is oxidized to CO2 and final emission of CO is very low indeed (a few parts per million). However, in systems which have low temperature zones (for example, where a flame impinges on a wall or a furnace load) or which are in poor adjustment (for example, an individual burner fuel-air ratio out of balance in a multiburner installation or a misdirected fuel jet which allows fuel to bypass the main flame), CO emissions can be significant. The primary method of CO control is good combustion system design and practice. 

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