On August 13, an exceptional situation occurred on the premises of Unipetrol, the Czech Republic’s largest crude oil processor. The cause of the event was an irregular episode with one of the emergency safety valves located in the steam cracker. Despite its great intensity, the resulting fire was extinguished after five hours thanks to Unipetrol’s immediate reaction and close cooperation between internal and public fire rescue services. And while the situation in the North Bohemian town of Litvínov, where the chemical complex is located, was calming down and refinery workers were assessing the damage, a plan for the fast and safe recovery of the damaged production unit was already being drafted.
"3 days after incident the first
Linde experts arrived on site."
Rebuilding the steam crackers
“As soon as we learned about the accident through the media, we contacted Unipetrol to offer our repair services,” explains Dr Detlef Kracht Project Manager at Linde Engineering in Dresden. Although Linde did not build the original steam cracker in 1980, it did a revamp in 2007. As such, Kracht and his team were already very familiar with the plant layout. In addition, the two companies had collaborated on projects in the past. This was undoubtedly one of the reasons why Unipetrol involved Linde in the damage assessment process in September and then awarded Linde the EPC (engineering, procurement and construction) contract in early October 2015 to rebuild key sections of the damaged plant. “We inspected the site just three days after the explosions, once the fire-fighters had declared it safe to do so,” recalls Kracht.
Example of a polypropylene plant in Russia
An elaborate safety concept
The large number of contractors involved had to be jointly managed by Unipetrol and Linde Engineering. Both knew that the only way to guarantee a smooth workflow was to closely align concepts and timelines. The biggest challenge, however, lay in developing and coordinating a safety policy for the plant so that workers would not be exposed to danger. “It was vital to make the plant safe, for example by setting up scaffolding, securing areas in danger of collapsing, getting rid of live wires and eliminating hydrocarbons from pipelines,” explains Kracht. “We carried out thorough inspections of each unit and the working conditions before embarking on every new stage of the project. It was definitely more of a parallel process than you would find when constructing a plant from the ground up,” comments the Linde expert. A total of 50 Linde Engineering employees were deployed on site. An integrated task force was built especially for this challenging project, bringing experts from Dresden together with employees from Unipetrol and technical experts from the insurance companies. “So we had all the necessary people with all the necessary expertise on board,” adds Kracht. By the time the project was completed, over 1,000 personnel had been deployed at the Unipetrol site.
The fact that no injuries were sustained during the entire ten-month reconstruction project is a source of great pride for the Linde expert, as is the fact that the work was completed ahead of schedule. It took ten months – from the damage assessment in September 2015 till July 2016 – for Linde to complete the mechanical work. Demolition of the four damaged furnaces and handover of the site in readiness for the new furnaces took place one month earlier than planned. Plant component repair work was also completed with one week to spare, which meant that Unipetrol was able to restart its ethylene plant operations in October 2016.
Workers at a refinery plant