Flare Stack Deconstruction, Stanlow Refinery – Case Study

John F Hunt Regeneration (JFHR) was appointed by Essar Oil to carry out the deconstruction of a severely corroded heat shield located 100m up a live pressure relief flare system at a Tier COMAH site in Northwest England.

Due to the critical nature of the live flare systems—comprising three active units and one standby—conventional access and shutdown were not feasible.

Scope of Works

• Remote high-level deconstruction of a corroded heat shield at 100m elevation on a live COMAH flare stack, with no system shutdown possible.
• Bespoke crane-mounted platform design to safely deploy and operate a Brokk 90 robot with shear from ground level.
• Use of advanced remote technology, including wireless comms, fixed cameras, and drones for real-time visual control and safety assurance.
• Safe execution in a live environment, with full coordination of emergency flare protocols, controlled debris drop zone, and protection of adjacent plant.

Project Complexities

Operational Constraints:

• The live nature of the flare stack precluded any shutdown or close personnel access, due to the risk of emergency flaring.
• The heat shield, measuring 1.5m by 4.0m, was structurally compromised and required urgent removal.
• All works had to be carried out remotely from ground level, within weather conditions suitable for crane operation.

Engineering and Design:

• Design verification of JFHR’s method using a Brokk robotic demolition unit fitted with a shear, operated remotely from ground level.
• Ensuring the Brokk could access the removal area from a crane-mounted platform, without slewing or lateral boom loading.
• The design and engineering of a bespoke platform to support the Brokk, mounted to a standard lattice boom, required complex structural analysis and coordination with the crane manufacturer.

Safety and Site Considerations:

• All operations had to prevent damage to adjacent infrastructure, including high- and low-pressure steam lines and small-bore injection piping.
• Wireless video transmission and constant communication between ground operators and crane personnel were essential.
• Emergency flare protocol had to account for safe crane withdrawal from 100m elevation.

Pre-Operational Activities

• Removal of Brokk’s drive bed to minimise weight.
• Fabrication and trial fit of the crane-mounted platform.
• Full operational simulation to validate platform reach and Brokk/shear envelope.
• Cable routing and generator setup checks.
• Establishment of a sanded, barriered drop zone for falling debris, managed by the client.
• Scaffold protection for critical adjacent plant and control systems.

Plant and Equipment

• 1200-tonne telescopic crane with fly jib.
• Brokk 90 fitted with shear attachment.
• 100m scissor lift (for ancillary access).
• Ground-based generators with bespoke cabling.
• IS radio communications, fixed cameras, and drones for real-time visual monitoring.
• Ground control station for all remote operations.

Execution and Completion

The Brokk carried out controlled removal of the heat shield in small, manageable sections to mitigate risks of structural collapse or unplanned flaring.

All works were conducted remotely from 100m below, with operators using real-time video and radio guidance to safely manage the demolition.

The crane and platform were positioned and operated without lateral force application or slewing, maintaining structural integrity throughout.

Outcome

The project was successfully completed under stringent safety, operational, and engineering constraints. John F Hunt Regeneration demonstrated its capability in high-risk, high-altitude industrial deconstruction by leveraging bespoke engineering, remote technology, and precise coordination with stakeholders.