Operator safely executes multi-well P&A campaign in the North Sea

Overview

A major operator contracted Halliburton Baroid for its Plug & Abandonment (P&A) campaign in the North Sea, UK. The campaign comprised of multiple wells including one in which the first use of a new casing milling technology was required. The Baroid separation solutions team recommended the BaraMag™ swarf separation and recovery unit designed to provide safe and effective handling of swarf and to minimize the impact of swarf on offshore equipment. Deployment proved successful, recovering over 95% swarf, avoiding non-productive time (NPT), HSE and service quality issues.

Challenge

The operator’s key objectives and challenges were to efficiently and safely separate and contain the swarf material into the skips. Failure to remove this harsh metallic material can lead to excessive wear and tear on rig surface equipment; contamination of drilling fluids; and health, safety, and environmental (HSE) risks to personnel. Traditional solids-control shale shakers are not the best tools to remove this significant quantity of swarf from the fluid at surface. Removal of swarf from a milling fluid requires a reliable and efficient means of separation at surface to ensure successful operations.

Results

First milling section

The milling of the first section was successfully completed over two days without any operational impact. This included continuous operation of the system with a rotating crew of specialized swarf handling operators. The section was milled from a depth of 1,250 m down to a depth of 1,280 m giving a total depth milled of 30 m. Total Swarf recovered through BaraMag™ system was 2,074 Kg and was contained into 1 x skip.

Second milling section

The milling of the second section was completed over four days. This section was milled from a depth of 900 m down to a depth of 965 m giving a total depth milled of 65 m. Total Swarf recovered through BaraMag™ system 4,755 Kg. and was contained into 2 x skips.

Conclusion

The first successful deployment of the BaraMag™ system allowed for the operator to successfully mill and handle returned swarf on surface without NPT or HSE incidents. The economic value of the returned milling fluid and the minimization of waste were crucial in successful milling and ultimate completion of the P&A scope for that well, maximizing operator asset value.