Investing in batch automation to limit your facility’s risk in a future pandemic will most likely pay for itself in many ways that were not originally considered.
BY MICHAEL MCENERY JULY 8, 2020
The effects of the COVID-19 pandemic on the manufacturing industry illustrates the need to move operators away from the process equipment and into a controlled, and possibly remote location. Automated batch control systems can meet this need while providing additional benefits to manufacturing plants willing to invest in them. The most significant benefit may be enabling a workforce transformation when operators stop performing physical tasks and are given digital tools to improve process performance.
As the COVID-19 fallout has shown, significant ways to reduce risk and keep businesses operating safely during a pandemic is to reduce the overall number of people within an area, maintain safe distances between people, and keep all common worksurfaces cleaned and sanitized. Therefore, it would benefit manufacturers to reduce the number of operators physically required for a process, increase the flexibility of operator location while performing tasks and reducing hands-on operator activities.
Automated batch systems can address each of these and can provide additional benefits to assist with project justification return on investment (ROI). These include improved personnel safety, material tracking and tracing, regulatory reporting, reduced opportunities for operator error, increased production throughput, increased product consistency and quality, increased energy efficiency, reduced material costs and increased profits.
A significant long-term benefit is that by moving operators away from the process equipment and reducing repetitive and physically demanding tasks, and by providing modern control software tools for their use, it provides an opportunity to transform the role of the operators. It empowers them to identify ways to improve process efficiencies, prevent shutdowns and improve product quality.
Transitioning to human-machine interfaces (HMIs) is key to allowing operators to work from a remote location. By displaying information from process area input/output (I/O) devices on the HMI graphics, operators can monitor and control batch system equipment from a control room environment, or any other location away from the process equipment. This allows companies to space employees away from each other as well as removing the operator from the process area environment. This can reduce safety issues related to slips and falls, or health issues related to exposure to chemicals, dust, loud noise or hazardous equipment. It also can lead to a more productive employee by providing a comfortable atmosphere to work and think.
Tablet PCs can increase the flexibility of the operator’s location and reduce sharing computer equipment and are sanitized between shifts. While operators are in process areas, which will always be required to some extent, taking this portable HMI with them will provide real-time batch and equipment status.
Modern batch control systems also present process information on the HMIs in an intuitive manner to allow operators and maintenance technicians to observe process upsets, manage alarms and address equipment performance issues before these cause downtime or quality issues.
Typical human-machine interface (HMI) graphic for a batch vessel using ISA101 Best Practices.
Siemens SIMATIC HMI Basic Panel screen displays real-time machine data.
Manual batch systems require operators to control ingredient addition amounts by stopping a pump or closing a valve when a setpoint is reached, which means they are touching many surfaces and increasing exposure to or spreading of germs and viruses.
From a process performance standpoint, this approach introduces inconsistencies in the amount added due to subjective methods of stopping the addition, or worse yet, an operator forgetting to stop the addition altogether. This will likely result in a scrapped batch, raw material losses, lost production time and costs to dispose of the scrapped material.
Some existing batch systems may provide automated additions of individual ingredients but require the operator to enter setpoints each time a batch is run. Not only is this time-consuming and repetitive, entering these values over and over creates a significant source of operator error. The control panels used create another shared surface touched by multiple employees.
Automated batch systems control most ingredient additions and can provide increased consistency and accuracy. This improves product quality and can generate savings in raw material costs by reducing quantities of expensive minor ingredients that may have intentionally increased formula values to account for variability in additions.
Risk for operating in a pandemic environment is also reduced by providing flexibility of where recipe creation and change management is done. This allows the process to be managed away from the process area within the plant or remotely at a corporate level for multi-site corporations.
Manual batch systems typically have variability in the procedure used by individual operators, which can be eliminated by an automated system. Examples of this include starting, stopping and setpoints for auxiliary equipment such as mixing, recirculation, heating and cooling. These can introduce quality concerns, which can cause scrap, slow production times and customer satisfaction problems. Other factors that can be controlled to reduce product variability include the rate of material additions and the order in which ingredients are added.
Batch automation often requires significant modifications to the process equipment. For example, automatic additions of ingredients currently added by hand may require the installation of new hoppers or tanks loaded from supersacks or totes.
Piping changes may be required to add flowmeters for individual ingredients and control valves for each flow path. Accommodations to existing tanks will likely be required, such as adding placing tanks on load cells, and adding level, temperature, pH and pressure sensors.
While these equipment changes may be an expensive upfront cost, they may provide safety benefits significant enough to justify the project. These systems will likely eliminate repetitive heavy lifting or the need for an operator to be working on a platform and climbing stairs. It also can limit exposure to dust, chemicals or hazardous locations.
Another significant benefit of batch automation is capturing and storing process data for use throughout the production and business enterprise. Engineering can use data to improve equipment design and operation. Production can use it for scheduling, material tracking and inventory management. Quality assurance (QA) can use it to ensure product quality, material tracing and regulatory documentation. Maintenance can use it for scheduling preventive and predictive maintenance.
Most importantly, this data is available to the process operators. Software tools can present this information in meaningful ways in real time, allowing them to observe in detail how the process is running, what has gone wrong, what is about to go wrong and how to improve it. Because operators no longer have to spend their day on the plant floor using their body to start and stop pumps, open and close valves and lift bags and buckets of ingredients, they can dedicate significant amounts of time and effort to putting their minds to work at improving the process instead.
Automating a batch process provides benefits at many levels. Investing in batch automation to limit the facility’s risk in a future pandemic will most likely pay for itself in many ways that weren’t originally considered.
The most significant benefit is likely enabling a workforce transformation by moving operators away from the process equipment, allowing them to stop performing physical tasks, and empowering them to improve process performance with new digital tools. This approach allows them to become proactive thinkers and becoming a huge asset to the company.
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