Justin Beck

Review of battery safety for emergency communication and tracking systems for underground mining operations

The passage of the MINER Act of 2006 has placed stronger requirements on communication and tracking equipment used in underground mines for emergency operations. This review details the safety concerns of battery chemistries that are expected to see use in emergency communication and tracking equipment. The performance and safety requirements for portable and stationary equipment are summarised. Descriptions are provided for domestic and international standards regarding intrinsic safety. Common concerns for battery charging systems for underground mines are also addressed.

Surface and Electrochemical Behavior of HSLA Steel in Supercritical CO2-H2O Environment

General corrosion was observed on high strength low alloy carbon steel after electrochemical impedance spectroscopy experiments (EIS) performed in H{sub 2}O saturated with CO{sub 2} at 50 C and 15.2 MPa. However, general and localized were observed on the same material surfaces after the EIS experiments performed in supercritical CO{sub 2} containing approximately 6100 ppmv H{sub 2}O at 50 C and 15.2 MPa. The general corrosion areas were uniformly covered by the FeCO{sub 3}-like phase identified by X-ray diffraction (XRD). In the area of localized corrosion, XRD also revealed FeCO{sub 3}-rich islands embedded in {alpha}-iron. The energy dispersive X-ray (EDX) analysis revealed high concentrations of iron, carbon, and oxygen in the area affected by general corrosion and in the islands formed in the area of localized corrosion. The real and imaginary impedances were lower in H{sub 2}O saturated with CO{sub 2} than those in the supercritical CO{sub 2} containing the aqueous phase indicating faster corrosion kinetics in the former.