The ovens are fueled by natural gas. We have propane back-up systems. Propane storage can be several thousand gallons. These furnaces are fueled with natural gas with propane back-up as described in process 1 above. We do utilize chlorine in these processes.
Gaseous chlorine is pumped into liquid aluminum to react with and remove impurities.
We are aware that the chlorine process is covered under the PSM standard but are not sure about the propane used as a fuel in the same process. Thank you for your interest in occupational safety and health. If we may be of further assistance please contact us.