Jul-2022

Safety in turnaround power services

Renting power systems during a turnaround or unexpected shutdown must take into account the health and safety of contractors and plant personnel working around temporary generators, compressors, switchgear and other related electrical and thermal equipment.

Rene Gonzalez
Editor, PTQ

Article Summary

Given that temporary power requirements can suddenly develop in regions where hydrocarbon processing facilities are vulnerable to natural disasters, such as hurricanes along the U.S. Gulf Coast, the shut-down may be temporary but the risk can be higher than when the plant is operating normally.

That explains why safety of all personnel on-site is the most critical issue, especially around damaged machinery. Almost every thermally intensive conversion unit eventually encounters the need for rapid, often urgent, temporary power and temperature control deficits. This is when the need to quickly formulate a solution includes making certain that safety is never compromised.

Stewards of first-mover safety strategies are well-aware of the quantifiable benefits that a Best Practices safety approach can deliver for projects needing power and temperature control support. Sought-after benefits include options for safely building additional layers of redundancy at no additional costs. 

When considering critical utilities, such as the supply of power, the earlier a plant can consider a few key items, the more successful (and less stressful) a safe project can be. According to information from Aggreko LLC’s years of experience in helping the refinery and petrochemical industry resolve situations ranging from abnormal transients to over-current protection, best practices strategies have been developed when planning temporary power utility configurations, as follows:
Ensure that proper safety labelling and personnel protection equipment (PPE) protocols are followed: Safety labelling and PPE requirements have significantly reduced the threat of an ARC flash, which has been a danger for many different types of industrial processes and commercial projects.

Equipment placement and cable routing: After arranging for connection of generators for plant equipment and machinery/tools used during the turnaround, its optimal placement at the project site should be selected. In the case of relatively large projects, a distributed mini-grid style power configuration may be more efficient.

Create detailed one-line diagrams: Prior to the start of a project, such as a refinery turnaround, ensure detailed one-line diagrams are created for electrical power needs. The best one-line diagrams contain information regarding identification of all generators, transformers, circuits, and panel and cable sizes. These one-line diagrams ensure equipment goes to the right locations, ensuring that life-critical systems stay active in case of faults. With these diagrams, everyone knows what to do and where everything goes.

Easy service access: Regardless as to the length of service required for temporary power, generators need periodic maintenance and may need to be refueled on a scheduled basis. This is obviously why generators should be easily accessible throughout the duration of a project. A generator's refueling schedule should be organized in advance and as accurately as possible. There’s nothing more unacceptable than lack of temporary power due to having to wait to for a refueling truck.

Secure the site: Like all high-voltage electrical equipment, generators, switch gear and cables in a plant can pose risks of injury and should only be accessible by trained personnel. To increase safety, perimeter fencing, and secure cables should be used to establish safety zones and decrease any potential hazards during a project requiring temporary, outsourced equipment.

Identify key contacts: With power and temperature/humidity control equipment and linked assets in place to support a project, a list of key contacts should be added to the project database in case of an emergency. These are typically facility personnel responsible for managing primary on-site equipment (compressor, motors, pumps, heat exchangers, etc.).

An important component of developing an engineering solution requiring power and temperature control equipment involves identification of hazards that could be encountered when connecting to the client’s assets. The endgame on any project is selection of the appropriate control strategy for harmful exposures, such as from asbestos, requiring CIH trained professionals with the capability and authority to take prompt corrective measures to eliminate this hazard, including shutting down work tasks if necessary!