In gas streams mercury typically exists in two forms; mercuric oxide (HgO) and elemental mercury (Hg). Mercuric oxide forms when the metal is exposed to air for long periods at elevated temperatures. At around 400°C mercuric oxide converts to elemental mercury. Mercuric oxide and elemental mercury are toxic substances which can be absorbed into the body by inhalation , through the skin and by ingestion. They are irritating to the eyes, the skin and the respiratory tract and may have effects on the kidneys, resulting in kidney impairment. In the food chain, bioaccumulation takes place, specifically in aquatic organisms causing higher food chain members to concentrate mercury.  Atmospheric mercury is produced from a number of industrial processes including coal fired power (65%), gold production (11%), cement production (6%), and non-ferrous metal smelters (like lead)(7%).

Mercuric Oxide (HgO) and Elemental Mercury (Hg)


As mercury typically exists in two forms, it is important to design a removal system based on the quantities of each.  Mercuric oxide exists as a fine particulate in industrial gas streams.  It is largely insoluble in water, hence particulate collectors such as fabric filters are used.

Elemental mercury is a gas, which is soluble in water, hence a gas scrubbing solution is needed.  This can be removed either through a chemical scrubber (absorption) or by activated carbon (adsorption).

Mercury removal plants typically have two stages either:

1. A particulate removal device (fabric filter or venturi scrubber) followed by a packed bed scrubber.

2. An activated carbon injection/mixing system followed by a fabric filter.

Please contact us so that we can determine what is right for your plant.

Equipment Options

Chemical Scrubbers

Chemical Scrubbers

Dry Scrubber (Including AC injection and fabric filter)

Dry Scrubber (Including AC injection and fabric filter)

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+61 (0)2 4272 5233