Faster tank turnaround with lower disposal costs
Safer confined space removal with no dust or noise
The Delfzijl Tank Park project involved the removal of internal coating from storage tanks at Shell Exploration and Production’s tank park facility in Delfzijl, the Netherlands. The facility operates a significant number of storage tanks that require periodic maintenance, including the removal and replacement of their internal coating systems to maintain structural integrity, prevent corrosion, and meet ongoing operational and safety standards.
Conventional methods used at the facility for internal tank coating removal had historically relied on dry abrasive blasting with sand or ultra-high pressure (UHP) water jetting. Both methods presented considerable drawbacks in terms of cost, waste generation, operator health and safety, and overall project duration. Shell Exploration and Production undertook an evaluation of the RPR induction system as a new and potentially superior alternative for this application, with the goal of establishing whether RPR could deliver faster, cleaner, and more cost-effective coating removal across their tank maintenance programme at Delfzijl.
The RPR induction system is capable of removing a wide range of coating types including fireproof paints, solvent-free epoxy systems, thick and difficult-to-remove coatings, glued or vulcanised rubber linings, and powder coatings. Each tank at the Delfzijl facility required the removal of approximately 215m² of internal coating, and Shell’s evaluation assessed RPR against both sand blasting and UHP water jetting on the basis of cost per m² stripped, waste disposal costs, operator safety, and overall project duration.
Removing internal tank coatings at an active industrial facility like the Delfzijl tank park presents a combination of operational, financial, and safety challenges that conventional removal methods handle poorly. Sand blasting, the traditional go-to method for this type of work, costs approximately 35 euros per m² stripped and generates 83.80 euros per tonne in abrasive disposal costs. The volumes of spent sand produced during the internal stripping of a 215m² tank are substantial, creating significant waste handling, transport, and disposal burdens that add both time and cost to every maintenance cycle.
UHP water jetting reduces the abrasive waste problem but introduces its own complications. At approximately 30 euros per m² stripped, it requires the use of high-pressure tools that pose their own safety risks to operators working inside confined tank environments. With two teams working simultaneously, UHP water jetting still takes approximately two and a half weeks to complete the internal stripping of a single tank, a considerable period of downtime for a storage asset that Shell requires to return to service as quickly as possible.
Both methods also expose operators to elevated health and safety risks, requiring specialised protective clothing and respiratory equipment. The dust generated by dry blasting and the high-pressure water and debris from UHP jetting create hazardous working conditions that demand extensive personal protective equipment and careful site management throughout the job. Shell’s evaluation sought a method that could address all of these shortcomings simultaneously, delivering faster turnaround, lower waste volumes, reduced operator risk, and a lower overall cost per m² treated.`
The RPR induction system was evaluated against both sand blasting and UHP water jetting on a cost per m² basis for the internal stripping of tanks at the Delfzijl facility. RPR delivered a cost of between 25 and 35 euros per m² stripped, equal to or better than UHP water jetting and competitive with sand blasting, while generating zero abrasive waste and eliminating the need for high-pressure tools inside the tank environment.
The practical throughput of the RPR system scales directly with the power output of the unit deployed. At 10kW, the system can treat 20m² per hour. At 25kW, this increases to 40m² per hour, and at 50kW the system achieves 70m² per hour across the same coating type. For the 215m² internal surface area of a Delfzijl tank, Shell estimated a total project duration of approximately one week per tank using RPR, compared to two and a half weeks for UHP water jetting even with two teams working simultaneously.
Beyond the speed and cost advantages, the RPR process offered significant safety and operational benefits for confined space work inside storage tanks. No special respiratory equipment or high-pressure tools were required, reducing the personal protective equipment burden on operators and making the working environment considerably safer and more manageable. The process generates no dust and no noise nuisance, and produces only the removed coating flakes as waste, a fraction of the volumes generated by either abrasive or UHP methods.
A further operational advantage identified by Shell was the ability to carry out tank inspection and repair work simultaneously with the coating removal process, since RPR does not require the same degree of exclusion zone management that abrasive blasting and UHP water jetting demand. This parallel working capability contributes directly to reducing the total downtime associated with each tank maintenance cycle, improving asset availability across the Delfzijl facility.`
