The Propane Dehydrogenation Plant (PDH) in Tobolsk is the largest among dozens of petrochemical plants built by Tecnimont in Russia starting from the thirties of the last century (the first plants were built by Montecatini and Montedison). 
The city of Tobolsk, with a population of about 100,000 inhabitants, is situated in Tyumen Oblast, Western Siberia, at the confluence of the lrtysh and Toboi Rivers.
The Client is Tobolsk Polymer LLC, a subsidiary of JSC Sibur Holding. In 2007 Tecnimont was awarded a first contract for the performance of all the activities necessary to prepare the Front End Engineering Design and the Cost Estimate in an Open Book approach. Furthermore, in order to optimize the execution schedule Tecnimont also performed part of Engineering and Procurement activities aimed at purchasing the long-lead equipment. In November 2009 Off-Shore and On-Shore EPC Contracts were signed respectively with Tecnimont S.p.A. and 000 Tecnimont Russia. The aim of the PDH Plant is the propane transformation into propylene, a monomer for polypropylene production and produces 510,000 tons of "polymer grade" propylene per year. The Plant is based on C3 Oleflex process licensed by UOP: the core of the process consists in the catalytic dehydrogenation of propane into propylene with continuous catalyst regeneration. The PDH process includes the following stages: feed treatment and purification, reaction with continuous catalyst regeneration, product separation and fractionating, utilities. Due to particularly severe climatic conditions with temperatures that can be lower than 40 degrees below zero, the construction activities during the winter months have been really challenging. Significant winterization operations were necessary in order to be able to work in such conditions and to go on with the activities. Those conditions had also demanded a special scheduling for exceptional transport as the limited river navigation period had to be considered.

Other key data of the Project are:

• 6,200 piles
• 22,000 cubic meters of concrete (cast in situ, precast)
• 8,500 tons of steel structures
• 15,800 tons equipment:
• Column: 100 m height, 10 m diameter, 1,100 tons
• CCR Module: over 400 tons, compressors over 250 tons
• Reactors: over 600 tons in total, Cold box over 300 tons
• 420,000 dia-inch (A/G piping)
• 1,200 km electrical/instrument cable
• 122,000 m2 insulation
• 3,500 loop checks