Blue Grass plant personnel are enhancing auxiliary systems to the Energetics Neutralization Reactors (ENR) to decrease formation of hydrogen cyanide and keep the workforce safe.

Over the past ten years, scientists have conducted a series of validation tests at bench and pilot scale of the chemical destruction processes that will eventually be used at the Blue Grass plant. During one of these tests, they determined that low levels of hydrogen cyanide could be formed during the energetics neutralization process. These levels have the potential to affect workers farther down the line working with a secondary treatment process to remove dissolved aluminum from one of the process streams.

Although these cyanide levels would be below worker safety regulation standards and pose no public or environmental risk, project leadership decided to enhance the system as a precautionary step to further ensure worker safety.

Enhancements to the energetics neutralization system consist of installing insulation around each of the three ENRs, installing an additional heat exchanger to increase ENR batch temperatures by approximately 60 degrees Fahrenheit (F) and installing equipment to cool samples that must be collected for laboratory analysis.

This increase in temperature will safely and efficiently destroy most of the cyanide without compromising the neutralization process or the secondary supercritical water oxidation process. The optimum temperature for the heating process is 300 degrees F.

One such construction activity for this redesign is to install piping and support work for the additional heat exchanger to be set in the second level of the secondary heat transfer room. Workers are also placing the sample cooler on the sampling line.

Next steps for this process include recertification in September 2015 to meet the American Society of Mechanical Engineers standards for the increased pressure and temperature.