High-quality modulating failsafe electric process control valve actuators have been selected for a critical flow control application in the Australian coal mining industry.
Salcan Process Technology manufactures wellhead skids designed for coalmine degassing duties. The remotely sited skids are used in conjunction with the firm’s control and telemetry systems to enable methane and other flammable gases to be extracted from underground coal seams prior to the commencement of mining operations.
Salcan director Vincent Cantwell explains: “The Rotork actuated control valve allows us to control the flow of gas while maintaining back pressure in the coal seam. Bluetooth technology embedded in a failsafe electric positioner package eliminates the need to enter the hazardous area surrounding the valve for set up and diagnostic functions.
“In operation, back pressure on the coal seam is reduced in a controlled manner to protect the seam, thus maximising gas extraction. For a coal mine this is critical for reducing the risk of an underground explosion; for a gas producer it is critical for maximising the yield.”
The successful use of Rotork CVA actuators for similar duties at remote sites on the Queensland LNG project has made an important contribution to the selection decision by Salcan.
Actuators impress in coal mine project
Sarah Kellett explains how an excellent track record helped secure actuator selection for a critical coal seam gas application
High-quality modulating failsafe electric process control valve actuators have been selected for a critical flow control application in the Australian coal mining industry.
Salcan Process Technology manufactures wellhead skids designed for coalmine degassing duties. The remotely sited skids are used in conjunction with the firm’s control and telemetry systems to enable methane and other flammable gases to be extracted from underground coal seams prior to the commencement of mining operations.
Salcan director Vincent Cantwell explains: “The Rotork actuated control valve allows us to control the flow of gas while maintaining back pressure in the coal seam. Bluetooth technology embedded in a failsafe electric positioner package eliminates the need to enter the hazardous area surrounding the valve for set up and diagnostic functions.
“In operation, back pressure on the coal seam is reduced in a controlled manner to protect the seam, thus maximising gas extraction. For a coal mine this is critical for reducing the risk of an underground explosion; for a gas producer it is critical for maximising the yield.”
The successful use of Rotork CVA actuators for similar duties at remote sites on the Queensland LNG project has made an important contribution to the selection decision by Salcan.
Reliable valve control
HART-enabled Rotork CVA modulating electric actuators provide reliable process valve control at approximately 2,000 widely distributed sites. In addition to the natural gas, the CVA actuators also control the flow on the extraction process for coal seam water, a resource that is treated for use by agricultural and industrial customers as well as supplementing domestic water supplies.
CVA actuators deliver continuous, repeatable modulating control with a programmable fail to position option. Resolution, repeatability and hysteresis performance is quoted at less than 0.1% of full scale, offering suitability for the most demanding control valve applications. Among other advantages, innovative CVA electric actuation removes the expense of installing and maintaining instrument air supplies at remote sites, where often the pressure of the gas itself is too low to provide a viable source for actuator operation.
CVAs are also preferred because electric actuation eliminates the release of any environmentally harmful gas into the atmosphere during valve operations. As illustrated by these applications, the low power consumption also enables operation from renewable power sources such as solar panels.
Sarah Kellett is with Rotork. www.rotork.com
