Additionally, cristobalite was identified in the linings of the reactors. Our in-house asbestos resource removed this material to CAR2012 standards and our own standard operating procedures.
We developed a line-breaking strategy to check for the presence of residual product in all process equipment, including lined, tiled bunds, pits and sumps, which may have had trapped product behind and developed a secondary cleaning wash bay to clean all scrapped equipment prior to dispatch.
Similarly, heat exchangers with plugged tubes and lined/clad vessels had product trapped behind and required an elevated level of vigilance when considering the use of hot cutting methods during processing. Hydrocarbon residues were considered as present throughout the whole of the process. Therefore, hot working was restricted to structural steelwork only, with preference given to unbolt and cold cutting.
Paraxylene 4 Plant included a significant maintenance workshop, cooling tower, storage tanks, pentane fin fan condenser, control room and sub-station, pentane storage vessel, and pentane distillation column. Structures were up to 30m in height.
Paraxylene 5 Plant cold end included purification section, recycle section, depentisation, crystallisation, refrigeration, workshop and offices, control room, and switch house. The sheer size and scale of this area demanded three large excavators to deal with the robustly constructed nature of the plant process system.
Paraxylene Plant hot end included the intermediate storage compound, distillation, isomerisation, and catalyst silos. The notable work in this area was the controlled felling of two distillation columns, which were approximately 5m diameter and 41m in height.
The 65m high flare stack represented a significant challenge to the site team. Our site team successfully dismantled the flare stack in five distinct sections over live flare header systems with full COMAH lift controls in place. They utilised a 500t Liebherr mobile crane with full ballasting and a Grove GMK6300L with fly jib for man riding duties.