A plant revamp is much more than just a scheduled shutdown: Done right, it can become the perfect solution to re-establish competitiveness and comply with regulations and market demands — As good as new or even better: Plant revamping to achieve capacity increase, modernization to conform to ever changing regulations or product diversification can put an established production site back on top of the competition. But such delicate rejuvenation projects require dedicated specialists. With the right partners, a production plant can stay forever feasible …
All process plants require regular maintenance: Just like a race car at the pit stop, productions sites are shut down on fixed intervals. Within a scheduled timeframe, pipes, vessels and reactors are disassembled, checked, and, if necessary, repaired. Speed is king: Every lost production day translates to huge losses in terms of turnover and profits. Once green light is given, the production is back on the track, as good as new. But it could, in fact, be even better.
Plants that were constructed between the 1960s and 1980s are starting to show their age. Tougher environmental and safety regulations make life difficult for operators. Market shifts demand a more diversified product spectrum. And newly constructed mega- plants put competitive pressure on existing sites. But who says that you can not teach an old dog new tricks? When only the best is good enough, it is worth to consider a revamp. Specialized companies add valuable expertise and tailor-made technologies to modernization projects.
Companies like EPC Engineering & Technologies. Over the years, the German technology provider has been awarded numerous prestigious contracts for site revamps in the polymer and chemical sector. No matter, if capacity is to be increased, product diversification is needed or an existing site is to be retrofitted: EPC is up to the task. “The combination of engineering services and technology competence sets us apart from other providers”, states EPC’s Managing Director Tim Henkel.
Take for example polyester: The thermoplastic material makes up 18 % of the global polymer production. No wonder, this market attracts fierce competition: China dominates PET production for fibres with a market share of over 70 %. And, while production costs are more or less same across the world, the fast growth demand and raw material availability has driven new investments to Asia. But with a few tweaks, existing sites can take up the challenge. Using EPC’s PETvantage technology, capacity lifts up to 100 % are possible, requiring only minimal change to the reactors.
The use of smart project execution and pre-assembled equipment leads to short down-times. In fact, EPC states that a complete site can be revamped within a single year with an return of investment in less than two years, depending on the local conditions. But there’s more: A revamp can enable a plant to convert alternative raw materials or to produce new polymer grades. This technological leadership convinced Sabic to entrust EPC with the world’s largest PET revamping project in 2011. The project in Yanbu, Saudi Arabia, involved the process re-designing as well as the integration of new technology, including EPC’s own Inside PET process control software. With EPC’s in-depth know-how and experience, the revamp required no change of the melt phase reactors, even though the capacity was lifted from 400 to 1, 000 tons/day.
Plant Revamp vs Plastic Waste
Fit for the future: The plastic waste debate has put biodegradable polymers back on the agenda. But that is easier said than done: In fact, even biobased plastics can not always be decomposed, since this process solely depends on the chemical structure of the molecules. But how to produce a plastic that composes? Ask the experts: EPC Engineering & Technologies has bundled its experience to develop a technology for the production of biodegradable materials like PBAT (polybutylene adipate terephthalate), a biodegradable polymer based on synthetic raw materials. The polycondensation process uses 1.4 butandiol and a combination of dicarboxylic acids.
One significant advantage is that the spent-BDO, THF and water are collected, treated and reused. While the liquid spent-BDO is recirculated into the process, the recovered THF can be sold to the global market as a highly valuable organic solvent, fullfiling EPC’s Circular Economy-Standard. Adding a PBAT production during a revamp becomes an investment in the future.
New Life for a Process Superstar
Ask anyone to name a synthetic fibre, the name nylon will inevitably turn up. And no wonder: When the first nylon stockings were introduced in 1940, four million were sold within days. This polymer superstar is also used for tyres, resins, packaging and filaments or extruded into rods, tubes and sheets. Both in its original form as PA6.6 or as the very similar PA6, it offers high viscosity, good processability and low slip properties.
Already in 1942, the first polyamide silk was spun in Schwarza, Germany, right next to one of EPC’s subsidiaries. Today, the company looks back on its long experience in the supply of PA6 and PA6.6 systems. No wonder that EPC is one of the first names that springs to mind for the modification of polyamide production with dedicated technologies like the production of polyamide copolymers by means of a co-polymerization of caprolactam and nylon. Another proprietary technology is EPC’s PA6 extraction process named PAtraction, which helps to achieve an optimum material exchange, using nitrogen degassing, combined with higher pressure.
This not only significantly reduces the extract content in the granulate, but also enriches the extract water to about 18 %. But that is not all: PAtraction helps to achieve distinctly higher standardisation of retention. And the best: The process can be implemented in existing systems without major investments. Several successful revamp projects, for example for UBE in Thailand (where EPC not only provided the general planning, but also supplied equipment and supervised assembly and commissioning) underline the potential of this technology, Henkel states.
Revamping Light - Can it Be Done?
Sometimes however, it is not necessary to tackle the reactor or process setup at all: In many cases, retrofitting the piping systems is enough to achieve plant modernization. With that idea in mind, Unifi, one of the world’s leading innovators in synthetic performance fibers, entrusted EPC with the pipeline design and equipment supply for a PET plant revamp in the USA.
For the basic and detailed design of the melt pipelines, EPC implemented its Varipipe calculation software — a product specially developed for the simulation and design of high-pressure pipes for viscous liquids. The software was used to calculate the optimum setup for the spinning process, ensuring the best possible product quality, maximum flexibility and economic efficiency. The revamp allowed Unifi to flexibilize its PET melt production to its extruders.
Revamp to the Future
Whether a plant is using an obsolete process or market demands require a more flexible production: A revamp is much more than an elaborated shutdown. Done right, it can breathe new life into an old site. But, as in motorsport, it is important to get the pit stop strategy right: As a first step, a plant assessment must be done to identify the bottlenecks and potentials. Taking into consideration the local conditions and future market demands, different revamp concepts will be created. The evaluation of the various scenarios will lead to an optimal investment path, plant output in terms of products portfolio and operation costs.
Then it is possible to boost production capacity significantly, just like Trevira did with the de-bottlenecking of an esterification unit: With the help of EPC, the line in Boblingen, Germany, was able to increase its output to 175 %. And that’s not all: The revamped facility enables Trevira to produce specialty fibers via a direct spinning process on a dedicated line. Just another example of how dedicated engineering during the project revamp can make a plant truly fit for the future.