Johnson Matthey’s Noble Metals business in San Jose, US fabricates nickel-titanium alloys into tubing, sheets and other fabricated components which are used by our customers to make medical devices
One of the main constituents in the raw material is nickel and much of the processing involves grinding, drawing, etching and cleaning, so nickel is prevalent in all of the effluent streams, from rinse water to simple 'mop water' used for ordinary cleaning purposes.
Until May 2011, the site placed its various aqueous based hazardous waste streams into drums and disposed of them through a hazardous waste contractor. The site has grown over the last ten years and these disposal costs had risen to become of one the highest manufacturing support costs at the site.
So in early 2010, the site determined to find a less expensive means of disposal. Evaporation was established as the best alternative but with hazardous waste, it was not straightforward. A consultant was appointed to help the site understand the regulatory requirements. Once these initial steps had been taken, a natural gas fired waste water evaporator was installed and the site applied for a 'permit by rule' – a type of permit, light on bureaucracy, that is available for certain activities in the US.
In May 2011, the evaporator was commissioned. The equipment takes all types of waste water, from sheet rinse water to the mop water used in cleaning the Rest Rooms. Some of it is highly acidic, some only mildly acidic – but it is all grist to the evaporator!
The year before the evaporator came into operation (2010/11) is taken as the baseline, when 188 drums of aqueous hazardous waste (10,356 gallons) were disposed of at a total cost $95,000, including the drums. The following year, the volume of effluent evaporated – instead of being disposed of in drums – was 9,540 gallons. The evaporator is powered by natural gas, but even with the fuel costs, a saving of over $92,204 was achieved in the first year of operation.