By turning waste into byproduct our Clitheroe, UK, site is helping reduce the amount of waste to sent to landfill
One product's waste is another product's raw material. This is the idea behind the circular economy: old things can be used anew. The principle also applies to waste streams from manufacturing. Our teams are always looking for new and innovative ideas to reuse waste from production processes in a completely different process or product. An effluent stream can become a byproduct ready for further use.
In 2013/14 new byproduct routes were identified for two effluent streams at our manufacturing site at Clitheroe in the UK.
The volume of liquid waste the Clitheroe site produces will drop significantly
To be classed as a byproduct, the waste must be capable of being used directly without further treatment. In 2013/14, 3,233 tonnes of one such byproduct, weak ammonium nitrate solution, was used as a raw material by a fertiliser manufacturer.
In April 2013 a successful outcome was reached with a new partner and the concentrated sodium nitrate was proven as a beneficial byproduct. This is because it is directly used as a 'sewer sweetener' - the sodium nitrate provides a form of chemical oxygen to the sewage / waste water process, required to assist aerobic digestion. This reduces the amount of mechanical agitation needed to provide the oxygen, reducing electricity consumption for the Waste Water Treatment Works. Also, in long sewer pipelines, it is the most practical method for waste treatment and corrosion prevention. The oxygen supports and helps the useful bacteria in the Waste Water Treatment Plant multiply so they can effectively treat the waste water. This development has resulted in nearly all of the sodium nitrate being utilised as a beneficial byproduct.
Complementing the work done to reuse waste solutions as byproducts, progress on reducing solid non-hazardous waste sent to landfill has been equally impressive. In 2012/13 the figure stood at 45 tonnes; in 2013/14 it dropped to 10 tonnes – a reduction of 78%. This is because all general waste that can't be recycled is now being sent for energy recovery, instead of landfill, by the general waste contractor.
The concept of waste having its own value underpins the various initiatives in waste reduction. In reducing overall landfill tonnages and turning waste into byproduct, the Clitheroe site is making a strong contribution to Johnson Matthey's target of sending zero waste to landfill by 2017.