During the pandemic, dozens of chemical and allied plants have been started up remotely. One of the exciting tools that make this possible is the AI-based “Digital Twin”. This promises to become the new normal in the complex process of commissioning chemical plants.
The coronavirus exploited our natural propensity to socialise and wreaked havoc on our lives and livelihoods. Forced to stay apart and isolated from one another, we found ingenious means to collaborate and develop vaccines that will neutralise the virus. It is a triumph of the doughty human spirit over debilitating adversity.
The pandemic has destroyed time. Many activities of economic importance have been rudely grounded to a standstill. Some of these activities have resumed in fits and starts with many caveats and restrictions in place. On the other hand, human beings have displayed remarkable agility and adaptability to move many interactions to virtual platforms. We have become adroit in working, learning, and shopping while remaining confined within our homes. The pandemic has shrunk space and distance in ways that we have not imagined. Some of these tectonic shifts in behaviours are likely to be permanent as we have spotted huge economic benefits in them.
Plant Commissioning
Commissioning is the culminating step in a series of complex and interrelated tasks that constitute the establishment of a chemical plant. It is the event in a project that is most eagerly anticipated by the many stakeholders, none more than the investors who have risked their money and time in the endeavour. The enduring patience with which the different stakeholders have been expecting the products and profits suddenly appears to crumble on the eve of commissioning. It is replaced by anxieties and misgivings on the outcomes. Will the plant deliver the promised performance? A delay in commissioning has serious consequences, besides the mental health of the stakeholders. The altered cash flow adversely impacts ROI. The idling may shorten the plant life. There is a threat of a competitor grabbing the market share. The enterprise could suffer a loss of reputation.
Pre-commissioning
Commissioning, on the other hand, is not a process that can be rushed through because of external pressures. Before the commencement of commissioning, the plant is put through a series of rigorous pre-commissioning checks. These checks carried out by multidisciplinary
teams ensure that the start-up is safe. The pre-commissioning checks establish that the plant has been constructed and installed as per the design intent. The compliance with the design has to be near 100% and discrepancies, if any, have to be documented and accepted by all the concerned parties. This is an extremely tedious and time-consuming procedure. The plant’s innards have to be next flushed clean. Remnants of construction inside equipment and piping can lead to choking and interrupt the start-up process. Depending on the process, certain sections of the plant would have to be dried next. Moisture beyond the permissible limit will accelerate corrosion during the start-up and may even lead to catastroph- ic failure of hardware. Certain other sections of the plant will have to be inert to avoid an explosive atmosphere once hydrocarbons are introduced. There are many other preparatory steps – calibration of instruments, tuning of controllers, mechanical run of rotating equipment – to name a few, that need to be completed before the actual start-up can begin.
Commissioning Skills
The actual process of commissioning consists of introducing the raw materials into the plant and carefully increasing the pressure, temperature, and concentration to the prescribed levels to get the desired product. Depending upon the process this may occur in a matter of a few hours or few days. It is usually a step-by-step procedure fraught with risk. The parameters have to be scrupulously observed with hawkish attention to detail. The increase in pressure and temperature has to be ever so gradual because this would be the first instance of the plant hardware experiencing such a severity. This is also usually the moment when there is a high probability of the equipment failing catastrophically. A heightened sense of alertness is required to spot any abnormal behaviour and correct or reverse the course of action in the shortest possible time. At this juncture, the controls would not yet be in place and manual intervention would be required.
Commissioning supervisors must possess abundant experience in managing such situations. Also, they need two important skills – the presence of mind and communication.
Remote Commissioning
It is hence a matter of great astonishment that plants have been commissioned remotely during the pandemic lockdown. These are not one-off incidents. There are dozens of stories of remotely supervised plant start-ups across the world spanning the entire spectrum of the industry. A seawater RO desalination plant was commissioned in Saudi Arabia by a specialist team sitting in Madrid, Spain. The large turbomachinery train of a Nitric Acid plant in Uzbekistan was remotely started up from Germany. A Polylactic Acid plant was remotely commissioned in China by Sulzer. This is particularly interesting because it is not run-of-the-mill technology. An Australian company in the Food & Beverage sector has provided remote assistance for commissioning and operator training for a plant in the USA. A Bromine plant was commissioned in India by remote supervision from Germany. Remote supervision has been used to commission cement plants in Africa and Latin America. The list is quite impressive. What is even more interesting is that these technology providers plan to incorporate remote supervision of commissioning as the “new normal” in future.
Digital Twin
Remote supervision of plant start-up was achieved through a combination of hardware and software. Additional CCTVs were installed in the plant and hooked up to large screens in a virtual control room located thousands of kilometres away from the plant site. In some instances, the remote supervisors were even given access to operate and control the plants from their virtual stations. An interesting innovation is providing cameras on helmets which allow the remote supervisor to virtually view and listen to what the operator in the field does. But the most exciting development is the use of Digital Twin technology. A “digital twin” is an exact virtual replica of the real plant. Data from the real plant is captured in real-time and used for simulation in the virtual twin, located oceans away. It is still a work-in-progress, but a mindboggling prospect.
Silver Lining
The exigency of the pandemic has given birth to many new practices. Some of them will take roots and not go away even when the pandemic does. Virtual Commissioning could be one of them because it has several advantages.
The Commissioning specialists are a relatively rare breed and many a time plant start-ups have been delayed due to their unavailability. Other times they are summoned too early to the site because of faulty planning and the customer incurs their high per-diem charges. This will be history when Virtual Commissioning becomes the norm. Also, the experts, who
are older people, need not be away from home for long times and expose themselves to risks. This could be one of the many slivers from the silver lining of the pandemic.
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