CUSTOMER: Shell, Stanlow Petrochemical plant, Ellesmere Port, UK

PROBLEM: The product passing through the catalyst in the 40 foot reactor vessels in the Neodol and Linevol plants produces a by-product which builds up as hard deposits in the pipelines and particularly the nozzles, restricting flow and reducing production efficiency. Traditionally, this would be chipped off by hand but this is no longer a viable option as the outage period would be considerable.

SOLUTION: Furmanite was called in and put forward an alternative solution using spark erosion.  As a specialised cutting technique that breaks down almost any metal or other fully hardened material into minute particles, spark erosion does not generate cutting forces and can be used where conventional processes are difficult, damaging or dangerous to use – as in this case. 

The operation involved an electrode held in the cutting head of the disintegrator, and combines a cutting action with a continuous series of high frequency electric arcs.  A non-hazardous coolant was pumped through the electrode to wash out the powdered waste material.   As the technology had not previously been used for such an application, trials were set up at Furmanite’s Kendal workshops, demonstrating that the objective could be achieved; the deposits were successfully removed by being turned to dust, with no load on the pipes.

OUTCOME: The work was successfully completed during the scheduled seven day shutdown. The nozzles had previously never been cleared so effectively. A combination of spark erosion and replacement piping returned the unit’s capacity to its original design capability.