Automatic control of soot and unburnt hydro carbons from flares in oil and gas industry

Flaring is a high-temperature oxidation process used to burn waste gases from industrial operations. Smoke results from combustion, depends on waste gas components, quantity and distribution of combustion air. Flares stacks are used in industries are often assisted with steam to ensure complete combustion and to avoid any unburnt hydro carbons. In this process, flares are often sooty due to insufficient steam. This results in black carbon from flares. Soot particles in the air are a contributing factor in respiratory diseases. The fine particles less than 3micron are the worst causes of lung damage due to their ability to penetrate into the deep air passage. This paper explains the health effects of soot and particulate matter. New scientific evidence has led to recognition of the significant role of black particles (black carbon - BC) as one of the short-lived climate forcers. Measures focused on BC and methane is expected to achieve a significant short-term reduction in global warming. The black carbon or soot from flares can be minimized by controlling steam to flare by automation. Flare gas flow measurement by ultrasonic flow meter gives a high turn down ratio of 2000:1. This paper explains the methodology of control of soot from flares by steam to hydro carbon ratio control and how the combustion efficiency varies with the amount of steam. The economical benefit of saving steam by automation is not only credit to the company but also carbon credit to the world.