Mercury in extraction and refining process of crude oil and natural gas

Abstract

Crude oil and natural gas are predominantly composed by hydrocarbon atoms, water and a wide spectrum of elements at low levels such as arsenic, vanadium and mercury. The presence of mercury in crude oil and natural gas varies in each stage of extraction and transformation process because it distributes unequally among the vapour, condensate and aqueous phase in function of the pressure and temperature. Mercury causes a wide range of problems for refiners as for example: equipment degradation, toxic waste generation, health impacts and poisoning of catalysts. In order to remove the contaminant, there are different technologies based on adsorption, chemical oxidation, precipitation or ion exchange treatments. The use of each one depends on the concentration and the physical and chemical state of mercury in crude oil or natural gas.