Clean It NQ was engaged by Lanksey’s Constructions to clean TK310 at the PUMA ENERGY depot in South Townsville. The 40 mega litre tank required an internal clean to allow a product change from fuel oil to diesel.
Working under the eye of Lanksey’s Project Manager Bill Cox, Clean It was initially required to remove the fuel oil sludge from the floor of the tank to allow safe access and enable the internal tank cleaning to commence. In excess of 130,000 ltrs of waste sludge was removed from the tank through squeeging and industrial vacuum and transported under our regulated waste licence for disposal.
With an internal ceiling height of 44m, elevated work platforms were required to access the tank ceiling and allow cleaning of the ceiling, roof structure and tank walls. To achieve access to the tank for the EWPs, an access hatch was required to be cut in the tank wall 3.0m wide and 3.5m height.
As the site was a fuel depot, cutting the 30mm thick steel wall had to be achieved in an intrinsically safe manner. Clean It utilised its cold cutting capacity of its 40,000psi Ultra High Water Blasting Unit. The semi-automated process utilises a motorised guide to direct the garnet injected ultra-high pressure water stream to deliver a precise cut. The 13ms of cutting was safety achieved through the 30mm steel wall to precision accuracy at a rate of 25mm per minute.
The internal tank walls were cleaned through a combination of 40,000psi ultra pressure cleaning at up to 25ltr per minute to remove the bulk of the product and finished with a hot wash at 90oC at 3000psi to remove any residual staining.
The tank was cleaned in a confined space environment with controlled access and strict atmosphere monitoring. Two 450mm exhaust fans were used to circulate the air to maintain a non-toxic work environment. Respiration was used to protect our operators from inhaling fuel oil waste fumes when the product is vaporised during the cleaning process.
Clean It was able to maintain continual cleaning during each 10hr day through job rotation, fatigue management and tight hydration controls. This was quite remarkable as the temperature in the tank was in excess of 530C.