Dioxins
Description
Dioxins are persistent environmental pollutants, they contain chlorine atoms and have a base chemical formula of C₄H₄O₂. They tend to have no colour or odour, and are extremely stable at atmospheric conditions..
Sources
Dioxins are largely produced as a product of the combustion of chlorine containing substances. Small amounts of dioxins can also be formed in the production of some solvents..
Environmental Impact
Dioxins are persistent organic pollutants (POPs), which means once they are released into the atmosphere, they take a long time to break down. Dioxins are highly toxics and can damage the human immune system and cause cancer. Exposure to high concentrations of dioxins can be fatal.
Control
Dioxins can be controlled by improving combustion efficiency to gain complete combustion. This can be done in several ways, by altering parameters such as air-to-fuel ratio, combustion temperature and turbulence or by use of a secondary combustion chamber. Absorption and filtration may also remove dioxins dependent on the properties of the media used..
Measurement
Alkali Environmental perform periodic measurements of dioxins in a gaseous streams from stationary sources in line with the standard reference method BS EN 1948:2006 and method implementation document EA MID 1948. We are currently working towards accreditation for this method whereby the reported results will carry UKAS and MCERTS accreditation where the method can be performed to the standard.
These measurements are taken using a manual sampling train whereby a single result is obtained for a gas sample taken from the duct.