Case Study: Ensco 92 Drilling Rig - 92 tons of Sludge Removed from Tank

Location: Verolme Shipyard (Netherlands)

Operator: ENSCO

Removal of approximately 92 tons of sludge from a drains tank using vacuum transfer technology, whilst the rig was moored in the Verolme shipyard.

Sureclean Scope

Provide manpower and equipment for the removal and disposal of 92 tonnes of oily sludge from the No9 tank onboard the Ensco 92 by means of vacuum transfer application.

Technical Challenge

Tank was located at the bottom of the hull and was designed with a double bottom comprising of eight compartments, dimensions of which were approximately one metre in height and 20 metres in length. 

Restrictions / Considerations

  • Hazardous Environment - Confined Space Entry Working, access and egress.
  • Design / Layout of Tank.
  • H2s presence.
  • Waste containment and transfer.
  • Critical Path Project.

Key Facts

  • Project completed without safety or environmental incident.
  • Project completed on time and within budget.
  • Involved 5 Sureclean personnel, dayshift working.
  • Minimal man entry achieved.
  • Commendations received from the client.

Additional Information

The normal hazards associated with such a project was hightened by complexity of the tank layout, providing a technical challenge. However the use of of vacuum transfer technology enabled the project to be completed both safely and effciently, significantly reducing the requirement for man-entry and associated risks.