Delivering for AVAL, Algeria

Overview
Our multi-discipline team from around our global network found an innovative, low cost solution to an unusual and high-risk decommissioning problem.  

Scope
Detailed engineering, procurement and construction services, for the decommissioning of an underground 40,000m³ liquid natural gas (LNG) storage tank, and replacement of over 1,100 pipe supports on cryogenic pipelines around the LNG plant, on the above ground LNG storage tanks, and at the LNG tanker-loading jetty.

Background
The LNG tank was one of the last remaining of its type in the world. Our decommissioning team’s top priority was to ensure the safety of the local communities situated just beyond the boundary of the plant.

Challenges

• Removing the -162°C LNG without the walls of the tank collapsing as they warmed
• Filling the tank with sand while ensuring the ingress of air and static electricity from the sand did not cause an explosion within the tank
• Ensuring all LNG had been removed to ensure no uncontrolled releases of gas

PSN's approach

• Our focus on safety above all else has made this a success
• PSN's global network was put to good use by drawing on experts in process studies and safety engineering
• Our project team is building a relationship with a local children's charity, which is a first step in getting to know and make a positive impact on the local community

Achievements

• PSN Core Value award for health and safety, for overcoming huge safety and technical challenges in decommissioning the enormous LNG tank