Chemical clearance coordinated by RVA

Seeking the advice of a specialist engineering consultancy can reveal previously unconsidered opportunities and considerable cost benefits, as INEOS ChlorVinyls, Europe's largest polyvinyl chloride (PVC) manufacturer, has found after appointing RVA Group to manage large-scale UK decommissioning projects in Barry and Runcorn.

RVA commenced its role at INEOS ChlorVinyls' Barry site after manufacturing ceased in March 2010 as part of a consolidation of activities. Having planned to decommission and clean the site before handing it back to the landlord with the plant intact, INEOS sought RVA's isolation and decommissioning guidance. However acknowledging the financial implications of INEOS' proposed site exit strategy, RVA conducted a series of in-depth feasibility and option studies to investigate more commercially attractive routes for the client.

RVA recommended that INEOS hand the site back as flat slab, as plant demolition and dismantling could generate an income from the sale of the process equipment - some had potential for reuse whereas other items (as a result of their high-value metallurgy) would create a positive income stream.

To demonstrate their confidence in the proposed alternative site exit strategy, RVA agreed to work for six weeks - at risk - to test the feasibility of their solution. If the project plan had proven unachievable, RVA would have waived all costs for work undertaken during this investigatory period.

However, as RVA had anticipated, the team was able to demonstrate that the project could be delivered with significant cost savings, thus reducing the financial burden for INEOS.

Now RVA is project managing the dismantling and demolition of INEOS ChlorVinyls' production facilities including process vessels, aluminium and concrete storage silos, a boilerhouse and three steel 1,500 cubic metre (53,000 cubic foot) storage spheres. With a 27 man team on site, and equipment ranging from excavators with shears and grab buckets to an ultra high reach excavator, safety remains the number one priority.

Since the sequential decommissioning and demolition of five redundant chemical processing plants began on the high-hazard Runcorn site in August 2010, the site has remained operational elsewhere. Meticulous planning and project coordination has therefore been essential to ensure minimal disruption and utmost safety for all parties.

Priority was given to the complex dismantling of INEOS' four distillation columns, ranging from 40 to 60 m (132 to 197 ft) in height, which had to be dismantled to a low height before the arrival of the year's high winds. However due to their proximity to high-hazard pipelines, and given the inherently dangerous nature of hot-cutting techniques, an alternative dismantling process had to be devised. Instead RVA oversaw the more time-intensive, but far safer alternative, of using high pressure abrasive water jets that ran around the circumference of the columns' cut lines to eliminate the flammable risks, before the top sections could be removed with a lifting nail attached to a 500 tonne crane.

With six months of the programme still to complete, RVA is currently planning for the dismantling of INEOS' anhydrous caustic soda plant - a procedure that will take place in May 2011. Although the asset is no longer needed by INEOS, the plant is in good condition and is being carefully dismantled for re-erection elsewhere.