Generation and disposal of petroleum processing waste that contains mercury

The origins and fate of mercury found in hydrocarbons are discussed from th e perspective of waste minimization, treatment and disposal, Mercury is a c ommon and naturally occurring component of petroleum. Petroleum processing often is accompanied by generation of waste streams that contain some mercu ry. These waste streams become problematic when the mercury concentration i n process feeds exceeds a few ppb because of the highly toxic nature of mer cury. Waste is minimized by mercury removal systems that are now prevalent for ma ny processes, but the main incentive to employ such systems is to protect e quipment and catalysts. The removal systems have varied waste disposal cons equences depending on their chemical properties and process location. Absen t mercury removal systems, mercury contamination results in sludge, sedimen ts, contaminated treatment fluids and a variety of other waste streams that must be carefully controlled segregated and treated for disposal. Waste containing mercury is characterized by chemical analysis that is capa ble of speciating the various forms of mercury and mercury compounds so as to be able to select treatment and disposal options. In many locations wher e the mercury concentration in process feeds is high, treatment systems for mercury are not readily available resulting In storage of toxic material f or long periods of time. Both chemical and thermal treatment systems are co mmercially available, but access to cost effective treatment is extremely l imited in the petroleum industry.