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Case Studies

130' Crude Slop Tank

At a Western Canadian refinery, RJ Maclean was asked to circulate, process and clean a 130’ Crude Slop Tank for inspection. The client estimated 2-3’ of H2S laden sludge in the bottom of the tank. Using multiple SandPiper packages, and a client supplied light end hydrocarbon diluent, the tank was circulated to create a pumpable slurry for draw down from the tank. With the reduction of disposal volumes being a significant client focus, RJ Maclean employed a two-phase Centrifuge to separate the residual crude oil and hydrocarbon diluent from the solids, fines, and sediment. The Centrifuge processing continued during the Robotic Manway Cannon washing phase to re-circulate and re-use the wash water volume require for cleaning. The results were significant; an estimated 80% reduction in waste disposal volumes and a 60% reduction in water usage.

120' Crude Oil Tank

At a Western Canadian refinery, RJ Maclean was called to assist with the degassing, sludge removal and fine cleaning of a 120’ Crude Tank for inspection and repair. The client suspected damage to the Internal Floating Roof (IFR), which required the tank to be cleaned to replace the damaged roof sections. Due to the high LELs and concern over H2S, RJ Maclean performed a venting and degassing process, with chemical injection performed through the Robotic Manway Cannon system. Prior to energizing the equipment, a visual scan of the tank was performed using the HD video camera on the cannon. Through this scan, it was determined that the damage to the roof was more significant than expected. The visual confirmation provided a baseline for the damage to the roof, and planning for the required repairs. The tank was degassed and debulked with the Cannons, with manned entry performed for the fine-cleaning. RJ Maclean provided the engineered cribbing plan and cribbing installation to ensure safe entry for the cleaning technicians.

120' Skim Tank

During a Turnaround at a Northern Alberta SAGD facility, RJ Maclean completed the debulking and cleaning of a 120’ Skim Tank with an estimate 5’ of sludge on the bottom of the tank. Due to scheduling restraints and the intensity of the cleaning scope, RJ Maclean was challenged to provide a innovative approach to reduce the number of manned entry hours, while reducing waste volumes, all while meeting the cleaning schedule. Utilizing a full-suite of circulating and processing equipment, which included a three-phase Centrifuge, the tank drawdown was performed, with a specific focus on waste streams and volumes. As a result, the disposal volumes were reduced by half during drawdown. Next, RJ Maclean employed its full suite of Robotics; including manway cannons, and tracked vehicles to complete the de-bulking and sludge removal for disposal. The result; the tank was cleaned on time and on budget, waste disposal was reduced 60%, and the number of manned-entry hours was decreased by 70%.

95' Diluted Bitumen Tank

During a Turnaround at a Northern Alberta SAGD facility, RJ Maclean has cleaned a series of “DilBit” (dilute bitumen) tanks. Over the course of cleaning the series of tanks, the execution plans were refined based on the learnings from the previous tanks. Each of the tanks began with 4’ of sludge bottoms. The hazards associated with manned-entry for the volume of sludge and intensity of cleaning was a significant Client concern. RJ Maclean was asked to develop a methodology to reduce the duration and intensity of entries. RJ Maclean self-performed a series of “Cold Taps” to the tank manway flanges to allow access for circulation equipment. RJ Maclean employed its SandPiper circulation system to suspend the sludge bottoms with a pumpable slurry with boiler feed water added as a diluent and circulation media. Degassing was performed via scrubber venting and Robotic Manway Cannon chemistry injection. The result; the cleaning duration and intensity of manned-entry was reduced on each of the tanks, the waster streams were efficiently managed for disposal, and the majority of the tanks were returned to service ahead of schedule.

260' Crude Oil Tank

At an Eastern Canadian refinery, RJ Maclean was asked to perform a circulation, processing, and cleaning service on a 260’ Crude Storage Tank. It was estimated that the large diameter tank held between 5-7’ of high-paraffin Crude sludge (wax). RJ Maclean developed a methodology to heat and circulate the tank in order to create a pumpable slurry for processing and disposal. Utilizing the SandPiper circulation system and a three-phase Centrifuge, RJ Maclean performed the draw down and processing of the Crude sludge with addition of client supplied Boiler Feed Water and Diesel. The result; Crude and Diesel recovery was 90%, with the slurry pumped directly to process, and disposal volumes were reduced to damp solids from the Centrifuge.

122' Skim Tank

At a Northern Alberta SAGD facility, RJ Maclean performed a circulation on a 122' diameter skim tank to suspend the solids in the fluid prior to tank drawdown. This product was then processed through a tricanter during the drawdown where we separated the oil, water, and solids. Once separated we disposed of the solids, recycled the water for re-injection and transferred the oil back to off spec tanks thus nearly eliminating the disposal costs via water recycling and oil repurposing. Once drained we finalized the debulking of the tank utilizing RJ Maclean custom fitted robotics and finalized cleaning to a spec 1 level for the first time since construction.

60' Skim Tank

At a Western Canadian Upgrader, RJ Maclean was faced with a skim tank which was unable to be drawn down due to significant sand and solid buildup in the bottom of the tank. In order to remedy this concern RJ Maclean mobilized to site with our cold tapping technology to rig in our circulation equipment into the onsite manways ensuring that we maintained the structural integrity of the tank. Once rigged in we circulated the tank and were able to suspend the solids to a point where we could draw down the tank and perform the final Spec 1 clean.

7 Tanks Multiple projects

During a shut down for a SAGD facility, RJ Maclean took upon the role as prime contractor for the turnaround. Many milestones were made during this project most notably that we were able to clean seven (7) tanks in a nineteen (19) day time period all ahead of schedule. The advanced period allowed us to completely change the foreseen bottleneck and positively affect the entire turnaround. The utilization of RJ Maclean custom robotics dramatically reduced the manned entry of all tanks and were even able to complete Spec 2 cleanings without ever requiring any entry.