SECTION 2.4 ENVIRONMENTAL ISSUES (NEW)

A bromine spill or leak is very quickly indicated by the reddish - brown vapours and the harsh irritating odours. After someone becomes aware of a bromine leak, he should escape the irritating fumes while putting on the escape gas mask (if available), and walk quickly to towards a safe spot. From this safe spot, the person should warn other people not to go in the area and alert the police and the nearest fire department. Properly protected and trained responders should attempt to stop the leak, using emergency repair materials (i.e. wooden cones, lead wool, etc.), or by freezing the bromine at it's escape opening.

Attention is needed for the following environmental issues:

Bromine vapour

To avoid evaporation of bromine, several techniques are available:

  • Cover bromine by foam. Be aware that certain fire fighting foams have varying effectiveness in reducing the evaporation of bromine. The foams do not neutralise the bromine and are not instead of neutralisation materials.
  • Water spray can be used to knock down bromine vapours. When spraying water and when a bromine puddle is drenched with the water, there may be a temporary increase in bromine vapour emission. Once a water layer is formed the vapours will decrease. Also in this situation bromine is not neutralised.
  • Bromine vapours can be neutralised with ammonia vapours. Ammonia vapours should be released in the direction of the bromine vapour until a white cloud is formed (ammonium bromide). Using ammonia should be done by well-trained people. Ammonia itself is a dangerous substance.

Emission to water (sewer systems)

If bromine containers are stored within a bunded area then bromine leaks that  occur can be covered by a layer of water to minimize bromine vapours.  A minimum water layer of 15 cm is recommended.  Fire fighting foam (AFFF)  can also be used if more readily available though it could possible complicate remediation efforts.  Bromine spills contained in a bunded areas, ditches or sewers can be pumped out to a waste treatment facility for neutralisation or recovery.  Be aware that bromine and its vapours may persist in pits, hollows, depressions, sewers and confined spaces.

Bromine can be 'neutralised' in several ways as described in section 2.2. From and environmental point of view three situations might result from remediation efforts.

  • Bromine is absorbed in or on a material, but no chemical reaction has taken place.   Such materials should not be washed into waterways.  Post treatment is recommended.
  • Bromine has been converted, in part, to a bromate.  Bromates are substances with a high toxicity level for the aqueous environment.  Consequently, bromate emissions should be avoided at all time.  Bromates should be to reacted further to form bromides using neuralization chemicals described in section 2.2 (thiosulphate, bisulphite).
  • Conversion to bromides. This is the best solution to reduce the possibility of emissions that could harm the environment. It's not always possible to do this in one step. Sometimes one of the two above-mentioned steps is needed.

Soil pollution

To contain a bromine spill on the ground, earth and sand-bag dams should be built around the spill and the contained bromine neutralised with dry soda ash or a slaked lime-water slurry. 

Soils suspected of containing bromine residues should be collected as soon as access is available.  Slaked lime can be added to the soil to neutralise the bromine. The remediated soil should be put in emergency drums and disposed of according to local regulatory requirements.

Realisation: TiDi Graphics