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Refinery Turnarounds:
Raffinerie de Provence - Inspection and Maintenance of 4 chimneys on the East Refinery Vlissingen Refinery - Inspection and Maintenance of the Windshield and Flues
RAFFINERIE DE PROVENCE
The Brief This complicated brief required Delta International to go on site at short notice to carry out a thorough and detailed inspection of four chimneys. The primary objective was to provide a comprehensive analysis of their working condition. The inspection methods used included non-destructive testing (NDT) inspections, concrete core sampling, defect schedule, detailed drawings and measurements all backed up with digital photography. The shutdown was initially scheduled to last approximately 4 – 5 weeks. The Delta Difference Delta specialises in the inspection and repair of chimneys. Onsite, Total were impressed at Delta’s unique temporary works rigging techniques, particularly with the modular steeplejack scaffold used to erect a safe working platform, giving access to any position on the chimney exterior without the need for a full scaffold from ground level. As with many refineries, it is often not possible to permit a contractor to inspect and maintain the chimneys in perfect condition during long operating cycles. Fortunately, the length of this turnaround did allow for extensive inspection works and maintenance to prolong the life of these important assets. Delta International inspected the four stacks in the following order with subsequent repairs then carried out. Stack 1: Chaudiere 11 Cheminee Delta carried out detailed internal and external chimney inspections of the 70m high stack using a motorised cradle. A steeplejack modular frame scaffold was erected at the top of the chimney to provide safe access. The inspection provided accurate details of the chimney’s condition and consequently Delta recommended repairs to bring the chimney up to its optimum working standard. These repairs were then carried out within the planned shutdown period.
The main repair required on this chimney was the removal and replacement of the acid resistant brick lining Secondary to this, it was essential to re-instate the lightning conductor system which Delta’s operatives carried out with ease. In addition to this, they also installed a new stainless steel cap. Stack 2: Reformeur 5 Cheminee This second 70m chimney was inspected in much the same manner as the first, but the internal inspection was carried out using abseiling equipment. Delta’s recommendations were accepted by Total and Delta were required to install a suspended scaffold access platform on the inner rim of the steel lining to carry out the in-situ welding of a new steel capping ring. Delta also conducted external concrete repairs from the motorised cradle. To finish the job, Delta painted the upper 1.3m of the concrete shell with an MC Chemical protective coating. Stack 3: DG02 Cheminee This smaller, 30m steel heater chimney was inspected both internally and externally using abseil equipment. An additional inspection was carried out to determine the thickness of the shell, followed by further testing carried out by Delta’s own PCN qualified inspectors. Delta installed a full circumferential bespoke motorised platform to carry out the cleaning and painting of the shell. This platform was custom designed especially for the plant engineer, Frederic Alexandre, to ensure no paint spillages occurred from height. Delta completed the job by rigging an internal motorised platform to the stack to enable a Total engineer to carry out an extensive inspection of the completed work.
Stack 4: DG03 Cheminee This 80m chimney, with two steel linings, was inspected internally using a steeplejack modular frame secured to the chimney top. From this, the Delta team abseiled down the inside of the chimney. The external inspection was carried out with the use of the motorised cradle whilst an NDT thickness inspection was completed by Delta’s PCN qualified inspectors. The most urgent repairs required on this chimney were to the steel access ladders and rest platforms to secure safe access to the chimney. The top 1m of the steel liner was replaced, as well as the top 2m of the Sulphur flue lining, and a new permanent full circumferential steel platform was installed 2m below the termination. A new stainless steel roof plate was installed and the lightning conductor system was also re-instated to meet new European lightning protection standards. Extensive, essential concrete repairs were carried out on the concrete windshield across its full height and circumference. These vital and challenging repairs were all carried out by the Delta team whilst the chimney was still “on-line”. Delta were able to convince Total of their ability to carry out this on-line work, advised Total on the required safety precautions and co-ordinated the project under strict Health and Safety guidelines. Delta exceeded Total’s expectations and were commended for the quality of the inspection reports which were supplied to the Client promptly onsite. The multi-skilled team carried out all the works safely and efficiently during a very busy outage period without causing delay to others on site. Delta showed how they are “Totally Different, Totally Delta” by project managing the inspection and repair works so tightly that several hundreds of thousand of pounds were saved. There were no reported incidents or accidents and a big thank you was received from Total. Delta look forward to working closely with Total again in the future.
VLISSINGEN REFINERYThe Brief Total contracted Delta International to replace the existing stainless steel cap to the 130m high reinforced concrete windshield. During the fitting of this cap Delta were required to undertake a detailed inspection of the chimney to ascertain its current condition. The Delta Difference Existing access to the chimney was good. This enabled Delta to rig a temporary, full-circumferential modular scaffold platform to the chimney exterior. This was attached just below the summit of the windshield to provide a safe working platform for the operatives. The cap, which was fabricated by Total, was lifted in two sections by Delta into position using a 650 tonne crane. The new windshield was secured using chemical anchors. The inspection of the windshield and internal brick flues was completed utilising a man-riding basket attached to the crane as well as both abseiling and rope access techniques.
The project was completed in time and on budget with no incidents despite the teams initial set back of high winds. |
using new acid resistant bricks embedded with furane cement.
