Plant Turnarounds and Maintenance The Day the Refinery Stood Still
Fitness scheme for the plant: in a turnaround, every move must be right — When an “eternal” flame goes out for a while, something big is in progress: a refinery shutdown demands the utmost of operators, service providers and planners. When production comes to a standstill, the work of over 800 specialists really begins ...
A labyrinth of endlessly winding pipes, tall smokestacks and intertwined structures is what the workers in blue helmets and blue protective uniforms confidently wind their way through. They busy themselves with turning valves, welding pipes and putting up the scaffolding. They even get on their bicycles to reach their work locations more quickly as the 320 hectares of the refinery Mitteldeutschland are equal to 500 soccer fields put together. A 140-meter-high flare stack, its flame burning night and day, towers over the plant.
The refinery could aptly be described as a self-contained world of its own. The refinery, operated by Total of France, is one of the most modern industrial plants in Europe. Its output products include gasoline, heating oil, liquefied gas, diesel and methanol — indispensable raw materials for any economy. It is easy to see that operating and maintaining such a huge facility is no simple task.
The technicians deployed here by industrial services provider Bilfinger are no strangers to the challenges that the plant and its operation present. For 24 years now, the company has been working in Leuna, assisting with various modernization and expansion measures. Only recently, Total awarded Bilfinger two further major contracts worth roughly 30 million euros: the first involves exchanging the reactor systems, the second, performing the turnaround for the plant’s POX methanol facility. More than 800 specialists will be involved in these two projects.
Replacing the POX-Reactors: A 70 Tons Challenge
The replacing of the six reactor systems will have to be carried out in the midst of ongoing production operations and, if possible, without any downtimes. This is because the reactor systems, along with the downstream plant components, convert heavy petroleum residues into methanol, a key industrial chemical, by means of partial oxidation (POX).
This will be the most extensive refurbishment work ever done on the plant, which is one of the last industrial holdovers from the Communist period in Eastern Germany. The project is expected to result in a 20 % increase in the volume of methanol produced.
A project of this magnitude requires careful advance preparation: in fact, planning already begun in early 2019. Gerald Weber has been looking after the plant’s maintenance for a long time. The twenty-year veteran of Bilfinger’s Engineering & Maintenance service line explains how he and his team will bring the site up to the latest standard, “We will be removing and modernizing each of the reactors individually, which weigh between 60 and 70 tons — a process that will take 85 days each. Our tasks will also include building a new burner-cooling system.”
Planning Becomes Decisive in Plant Turnaorunds
Logistics present a particular challenge: the plant components are big and heavy. Thus, a special crawler crane with a capacity of 600 tons will be used to fit the reactors into place. Several days are needed to set up the crane and to prepare its operating lane — a process that will have to be repeated for each of the six reactors. Transporting the crane and its equipment will require some 50 trucks. Weber provides details, “Our services consist of more than the pre-assembly work and the conversion as such. Just as important is preparatory planning and coordination of the various trades on the site. In the end, everything has to run like clockwork.”
The reactors are scheduled to be replaced by the end of 2021, thereby completing the project. By this time, the second contract — the refinery’s turnaround in the fall of 2020 — will also have been completed. Gerd Braune, who supervises the turnaround at Bilfinger’s Engineering & Maintenance service line, explains, “Operators are obligated to shut down their plants at regular intervals. This sort of general inspection is intended to ensure that the plant remains technically reliable, legally compliant and environmentally friendly. We will be making the site fit for the next six years while providing top-to-bottom maintenance.” The refinery has to be kept idle while all this is going on, Braune points out, causing substantial turnover losses for the operator, “Our job is to keep these losses as small as possible. Every additional day of downtime increases the economic damage our customers stand to suffer.”
Keeping the Downtime as Short as Possible
In order to keep such downtimes as short as possible, Bilfinger has developed its own in-house concept for executing turnarounds. “How we go about it exactly is a trade secret,” says Braune and laughs, “But I can say this much: efficient scheduling and work planning are essential. Another factor is that our workforce is highly qualified and very familiar with the routines involved in such interventions. What’s more, we’re using digital solutions to an increasing degree.”
The results speak for themselves: every year, Bilfinger performs around 30 comprehensive turnarounds of industrial plants across Europe. The service field responsible for turnarounds has expended 4.5 million man-hours of work in recent years — and this without a single accident entailing lost working days.
Standstill or Headstart? Every Step Is Decisive
This hopefully will hold true also for the turnaround of the Leuna refinery, where Bilfinger acts as general contractor. The maintenance services must be completed within four to six weeks, including the opening, inspecting and cleaning innumerable containers and pipes — and of course also repairing them if needed. Subsequently, the individual components will be inspected and certified by the German Technical Supervi- sion Association TÜV. Braune, “What counts here is experience, familiarity with the routines, and keeping a cool head: every move has to be executed perfectly and the relevant steps have to be clear to all.”
To ensure that this is the case, giant workflow diagrams have been hung up, depicting the individual work steps and packages, which can then be checked off once they are completed. Thus, everyone is able to keep an eye on the big picture. As Braune puts it, “A turnaround is like a mosaic composed of many small tiles representing work packages, one that has been painstakingly planned two years in advance.” In fact, a planning period this long is indispensable: certain portions of the plant will be turned into huge construction sites, where many people will be expected to work in coordination at very close quarters. It goes without saying that, despite the intense time pressure involved, occupational safety and diligence will always have top priority.
Viable for the Future
The replacement of the reactors will form part of the “Leuna 2020+” measures intended to make the refinery viable for the future. By ramping up its production of methanol, the refinery is reacting to declining demand for heavy fuel products. Even during the standstill, the refinery compound in Leuna will see a lot of activity! DST