Natural gas is valuable both as a clean source of energy and as a chemical feedstock. To meet future demand for energy, offshore deep-water operations and unconventional offshore gas exploration and production will increase as conventional onshore gas resources dwindle.
This will require more sophisticated marine technologies, exploration in arctic regions and dedicated products. For example, drilling rigs operating in the North Sea and other arctic zones need to be designed for the harsh environment and need to meet stringent specifications.
The offshore gas industry offers many challenges for electrical heat-tracing solutions to ensure secure workflow. Germany-based Eltherm specialises in industrial heat tracing and has devised the following solutions with offshore LNG in mind.
Eltherm divides offshore gas applications for electrical heat-tracing solutions into three areas; winterisation, process and quarters comfort.
The first covers anti-icing or de-icing of escape passages, walkways, staircases and handrails, freeze protection for doors and escape hatches and frost protection for lay-down areas, helidecks, louvers, lifeboat davits and antennas.
The second application protects process pipelines and equipment subjected to cold and arctic weather. The target of trace heating these systems is, in addition to frost protection, temperature maintenance for the production process.
Several heating cables and junction boxes are available, including Elthermís round junction box Ex-It-R, certified for hazardous areas. Eltherm engineers developed the heating cables ELKM-AG-N, ELK-MI-VA, and ELSR-N for heating plants, as well as self-regulating high temperature heating cables ELSR-H and ELSR-SH.
As for protecting crew quarters, it is important to maintain hot water temperature and protect fresh-water pipes against frost. Frozen water pipes will burst, damaging the pipeline system, making it impossible to guarantee a reliable supply.
Process temperature maintenance applications require a properly functioning control system. Because heating systems must always be able to operate, they require built-in redundancy so that if any part of the system fails or shuts down, its back-up can pick up the slack until the primary mode of operation is restored.
Data integration, communication and user-interface preferences must also be considered when designing an integrated control system. These systems must be easily accessible, yet protected from unauthorised access.
The operator should be able to access key parameters locally, while the system should be able to transmit key data using industry-accepted data communication protocols.
It is important to take the ambient temperature, wind velocity and snowfall in the area of operation into account, as well as the water source, when designing the heating system. Eltherm electrical heat-tracing solutions prevent freezing for several applications, including exposed piping, tank vent, instrumentation, recirculation shell valves, overboard discharge and drainage.
The proper design and implementation of electric heat-tracing systems for offshore gas applications is critical to safe, reliable and efficient operations. Failures create significant costs and damages for operators and owners of the offshore facilities.