KIOGE-2026
From Extending Equipment Service Life to Building New Process Complexes. AVC Production solves complex engineering challenges at Kazakhstani refineries
AVC Production solves complex engineering challenges at Kazakhstani refineries
Until comparatively recently, the modernisation of Kazakhstan's refining capacity was associated above all with the construction of new process units, the increase in refining depth, and the shift to producing motor fuels of higher environmental classes. These objectives largely shaped the industry's development over the past two decades. Today, the projects coming to the fore are not necessarily linked to expanding production capacity, yet it is precisely on them that the reliability of operating facilities, product quality, compliance with environmental requirements, and the overall efficiency of refining depend.
The reasons for this transformation are entirely logical. A significant share of the process equipment at Kazakhstani refineries has been in service for several decades, necessitating new approaches to managing equipment service life. At the same time, the characteristics of the feedstock being processed are changing, and requirements for petroleum product quality and production environmental performance are becoming more stringent. Under these conditions, traditional solutions, the complete replacement of equipment or the construction of new facilities, are far from always the most rational. Increasing importance is attached to engineering solutions that enable the required result to be achieved with minimal intervention in the existing process scheme.
This trend is clearly evident in two projects carried out by the domestic company AVC Production at the Atyrau Oil Refinery and the Pavlodar Petrochemical Plant. Despite the difference in objectives, both projects share a common approach: the engineering solution was determined not by standard practice but by the specific process constraints of each plant.
Engineering Solutions Instead of Off-the-Shelf Scenarios
At the Atyrau Oil Refinery, during a technical assessment of the coke drums of the delayed coking unit, specialists identified critical metal wear in the most heavily loaded sections of the reactors. The standard way of solving a problem of this kind involves the complete replacement of the equipment. However, such a scenario would inevitably have required several years of design, fabrication of new shells, installation, and subsequent commissioning, which is unacceptable for an operating refinery, as it would require taking the unit out of service for several years and thereby substantially reducing throughput.
Instead, a fundamentally different concept was implemented. Only the most worn components of the reactors were replaced, the conical section, the support ring, and the lower shell courses, while the remaining sections of the shell, which retained the necessary strength margin, stayed in service. All the work was carried out during the unit's planned turnaround, thereby avoiding a lengthy production shutdown. Particular difficulty was presented by welding the new components to metal that had been operating under cyclic thermal loads for more than 40 years. Solving this task required the use of specialized welding technologies, careful control of thermal impact, and a full range of non-destructive testing of welds.
This project became an example of how modern engineering methods enable extending equipment service life without a capital rebuild of the plant. But whereas in Atyrau the main objective was to preserve existing production potential, at the Pavlodar Petrochemical Plant the task was already to create a new process complex capable of changing the quality characteristics of the manufactured products.
When Modernisation Is Not a Whim but a Necessity
The Pavlodar Petrochemical Plant was historically designed to process crude from West Siberian fields. After the collapse of the Soviet Union, the country had to find a replacement. The characteristics of the incoming feedstock changed markedly, and one of the most significant factors was the increased content of mercaptan sulphur, which gradually began to affect the composition of primary refining gases and the quality of the liquefied petroleum gases produced.
At the same time, in recent years, the requirements for the environmental characteristics of petroleum products have grown, and new Eurasian Economic Union standards governing the quality of commercial LPG have come into force. As a result, the plant faced a task that went far beyond the local modernisation of an individual process unit. It was necessary to create a new production element to ensure the product consistently met modern requirements without altering the overall refining scheme.
This is precisely why the decision was taken to build a new liquefied petroleum gas treating unit with a capacity of 100 thsd. tons per year, based on UOP's licensed Merox technology. For Kazakhstani refining, projects of this kind are of strategic importance not only for product quality. They allow plants to adapt to changing feedstock characteristics without the need for a radical rebuild of existing production capacity.
Why Merox
Among the existing technologies for removing mercaptan sulphur, the Merox process holds a special place thanks to its combination of high treating efficiency and comparatively low operating costs. Unlike most processes, in which reactions occur directly in the hydrocarbon medium, Merox technology relies on extracting mercaptans with a concentrated caustic solution, followed by catalytic oxidation in the aqueous phase.
After the disulphides are separated, the solution is regenerated and returned to the process, forming a practically closed process cycle. This approach makes it possible to substantially reduce the likelihood of by-product formation, to minimise reagent consumption, and to ensure consistent quality of the treated product.
For a refinery, such a solution offers several advantages at once. The quality of commercial liquefied gas improves, the content of sulphur compounds is reduced, the environmental burden on production is lowered, and the comparatively low consumption of catalyst, caustic, and auxiliary reagents ensures acceptable operating costs throughout the unit's life cycle. It was precisely this combination of factors that made Merox technology the optimal choice for the Pavlodar Petrochemical Plant.
A New Production Facility Inside an Operating Plant
The choice of technology, however, was only the project’s starting point. A considerably more complex engineering task proved to be accommodating the new unit within an operating refinery.
Projects of this kind differ fundamentally from building new production facilities on a greenfield site. Here, practically every design decision has to take into account the existing infrastructure, the utility networks in service, the process links between production facilities, industrial safety requirements, fire separation distances, and the scope for subsequent equipment maintenance.
Before construction could begin, it was necessary to demolish existing buildings and structures, relocate utility lines, establish a new site layout, and completely rework the equipment layout. The complex included extraction blocks for the propane-butane mix and for butane, caustic regeneration and neutralisation sections, and all the necessary supporting infrastructure: power supply, automation, communications, and instrumentation systems.
Particular attention was paid to equipment layout. The arrangement of the process vessels was determined not only by the requirements of the process itself but also by the scope for safe maintenance, scheduled repairs, and connection to the plant’s existing utilities. In effect, the designers had to fit a new production facility into an already established industrial environment without disrupting the plant’s established operating logic.
An equally important element of the project was the organisation of construction. The implementation period coincided with a time of serious constraints in international logistics, when the delivery of industrial equipment required constant coordination between manufacturers, carriers, and the construction site. Despite this, the entire equipment package was delivered on schedule, successfully passed incoming inspection, and specialists then began installing the process systems.
To bring together all the process streams, a three-tier pipe rack was built to carry the process piping, power supply networks, and the automated process control system. The piping itself was designed on the principle of minimum length, temperature self-compensation, and the ability to fully drain the product before repair work. Once installation was complete, all piping underwent hydraulic testing, and the most critical sections were additionally tested for pneumatic leaks. Quality control of the welds was carried out in full in accordance with the requirements of the applicable construction codes of the Republic of Kazakhstan.
The final stage was commissioning, during which the new unit was integrated into the primary crude refining process scheme. After the completion of comprehensive testing, the facility entered commercial operation in January 2025.
A New Quality of Modernisation
Formally speaking, the projects at the Atyrau Oil Refinery and the Pavlodar Petrochemical Plant are practically unrelated to each other. One is devoted to extending equipment service life, the other to building a new process facility. In reality, however, they reflect the same trend shaping the development of refining in Kazakhstan today.
Modern modernisation is less and less often reduced to building new facilities as an end in itself. Its main task is to find engineering solutions that enable the efficient use of existing production infrastructure, adapt plants to changing feedstock characteristics, ensure compliance with environmental requirements, and minimise capital costs and production risks.
This is precisely why engineering companies such as AVC Production are becoming increasingly important today: companies able to work equally effectively both on facilities requiring complex reconstruction and on the creation of new process complexes inside operating plants. Projects of this kind now demand not only construction competence but also a deep understanding of refining technology, the specifics of equipment operation, the logic of production processes, and the economics of the industry.
For Kazakhstani refining, this approach is gradually becoming the norm. As production assets age, process requirements grow more complex, and environmental standards are tightened further, it is precisely the ability to find rational engineering solutions that will determine the effectiveness of plant modernisation far more than the volume of investment or the scale of new construction.