Across Chemring, we are developing a sustainable water policy and seeking further water conservation opportunities throughout the organisation.
One such example is at Chemring Nobel in Norway. Chemring Nobel manufactures specialized energetic chemicals for the defence and civilian industries.
Wastewater from the chemical industry often contains high concentrations of organic compounds and treating it is essential. So, back in 2019, Chemring Nobel invested in a new, onsite wastewater treatment facility.
The £1.6m facility has two reactors, each with a capacity of 220m3. The facility processes around 3,000m3 of water per week. To put that into perspective, the average household uses around 164m3 of water over the course of a whole year.
The plant consists of two sedimentation tanks in parallel. The plant removes suspended material from the water. This mostly consists of explosive residues that are later destroyed at the fireground. The cleared water goes through for automatic sampling and water volume measurement. It is then released into the fjord, approximately 120 meters out and 52 meters depth on the seabed.
During the treatment process, bacteria ingest the hydrocarbons dissolved in the water, and air, heat and nutrients are fed into the reactors to create a favourable environment for the bacteria. Dead bacteria turn into sludge, which can then be discarded. The ‘bacteria-house’ within the plant measures is the equivalent area of 21 football pitches!
Chemical oxygen demand (COD) is used to measure the amount of organic compounds in the wastewater. The COD test is often used to monitor water treatment plant efficiency. The lower the COD figure, the more efficient the treatment plant. Since the plant became operational in 2019, the amount of COD accumulated weekly has reduced by a massive 80%.