So, what to do? Where to spend? What to prioritize? A mill’s to-do list is not void of good ideas.
This depends on where your mill is in its digitalization process and where you can achieve highest ROI. Every mill is different, and each has its own priorities based on the spec and volume of its output. However, there are some critical steps that are common to all mills looking to modernize and increase production.
Continuous, ongoing updates and improvements – taking small systematic steps, one at a time, all leading to the same end goal – will break down the complexity and risk of an infrastructure upgrade while allowing mills to test the success and return on investment (ROI) as they go.
To achieve optimal performance, you must be relentless about constant, incremental updates, no matter how small. It is critical to be able to see and measure results, yet a small number of mills still don’t even have basic online sensor measurements such as weight and moisture, for example. If you can’t measure quality, the consumption of raw materials such as fiber, chemicals and energy is often not optimum for the paper products produced, which affects your efficiency and productivity.
In one case, a central US mill had not invested in new technology for years but wanted to increase throughput by adding a new steambox. However, to handle the increase in available information and measure more accurately, management realized it would have to upgrade to a newer Quality Control System (QCS). This obsolescence conflict could have been avoided if the mill had kept up with equipment advances through regular upgrades.
Examples such as this abound. It is important to realize that the improvements that can be realized are not restricted to any one part of a mill’s processes. From wet end to roll handling, there are numerous opportunities, as can be seen by the following case histories.
- In Sweden, Holmen Paper Braviken is an example of how an optimization project can help to reduce downtime and improve runnability. Operational disruptions were affecting the availability of the mill’s RM3 winder, which produces jumbo rolls of printing papers weighing up to 50 tons. The mill opted for ABB’s automation and electrical system, upgrading to ABB Ability™ System 800xA, which included control and operation of the winder, as well as Winder Performance Optimization, which monitors KPIs, identifies improvement opportunities and enables the dynamic adjustment of speed to meet capacity for each roll set. This integrated solution drove better runnability, reduced downtime, easier troubleshooting, and increased productivity.
- In Asia, a major paper mill running a complex, 13-paper machine operation needed to maintain high production while being able to correctly predict service costs and constantly improve process performance. They turned to ABB’s remote monitoring and predictive analysis technologies. This helped the mill harness the tremendous amount of data to address production, quality and cost issues—one step at a time—and reduce both the time needed to complete bump tests by 70% and the overall loop tuning effort by 75%. This contributed to increased production, lower chemical costs, accelerated grade changing, fewer sheet breaks, reduced unplanned downtime and machine direction ash variability.
- In Sweden, a tissue mill had planned to install the newest technology on its PM 8 measurement platform. Its other paper machines had ABB scanners installed in the 1990s. However, some of the sensor material was radioactive which, as well as degrading over time, also presents safety issues. It was decided to install the ABB High Performance Infrared Weight and Moisture single sensor (HPIR-FW), which replaced two separate weight and moisture units, making for easier maintenance and improved reliability while also removing a source of radiation from the mill.