Advanced controls increase the stability of drying machines at Eldorado Brazil mill

The project carried out in partnership between ANDRITZ and Eldorado Brasil is further proof of how the implementation of advanced controls is capable of optimizing industrial processes and raising the operation to another level. With the adjustment in the control variables, improvements were observed in the process, such as a decrease in the weight variation of the units produced and less breaks due to variations in the parameter indications.

The industrial complex located in Três Lagoas, Mato Grosso do Sul, responsible for the production of 1.8 million tons of pulp per year, reduced the variability of humidity and grammage, enabling greater process stability for the Drying area. “The gains in operational continuity and process allowed a significant stability in the humidity of the dryer and, as a consequence, positively impacting, in a production increase of around 0.55%”, reports Israel Júnior, Regional Manager of OPP Operations at ANDRITZ.

Eldorado Brasil invests in more efficiency to exceed production expectations

Eldorado Brasil began operations in December 2012. Initially, the industrial complex was designed to produce 1.5 million tons of pulp per year. Today, almost 10 years after the start-up of the operations, Eldorado produces about 18% more than expected without any modification to the original project. “The mill has high efficiency, with a differentiated and shared management model, and high technical capacity of its professionals, taking care, in an exemplary way, of the company's assets and the training of its staff”, celebrates the Production Manager, Ademilson Carlos Zeber.

With the arrival of Metris OPP, the mill had the opportunity to further improve controls that worked satisfactorily and met process conditions. In the opinion of the Production Manager, the differentiated intelligence of the controls contributed to increasing the efficiency of the Drying area, reducing losses and downtime.

After “tuning” the process, increasing the availability of the drying machines, and increasing the average production, now the goal is to continue the optimization. “Our objective is to increase the area's OEE by up to 96%, and we are confident that this advance will be possible with the sum of all the collaborations of the operational team and the Metris OPP team”, comments Ademilson.

The constant search for improvements opens the way to new optimization opportunities

ANDRITZ's Metris OPP team has been working with Eldorado since 2017. This journey started with process improvement projects on the Fiber Line. Then, in the Caustification and Oven area and, finally, in the Drying area.

“That year, we started studies to define which control loops would be prepared for implementing the advanced Metris OPP control. Once the control loops were defined, a careful process was carried out to adjust their tuning. After adjusting, or changing the control logic, we performed some bump tests to define the gain for the OPP control. Based on the information obtained, the creation of the first advanced OPP control at Eldorado has started, which was the grammage control”, remembers Giovane Paulo de Jesus, Drying Specialist at Eldorado Brasil.

After the implementation of conventional controls in Drying, the area went through a review and creation of new controls, always seeking to improve the process, either by increasing production or reducing process variability. “Both teams looking for ways to work for the better of Eldorado Brasil. The good thing about having a dedicated ANDRITZ team at our plant is that it makes this thinking and interaction between teams a lot easier," says Gabriel Caldato, Drying Innovation and Technology Specialist at Eldorado.

Operator becomes process manager with the implementation of advanced controls

After reviewing and improving the controls, more up-to-date tools were used, such as the creation of virtual sensors, more complex logics and a greater amount of input variables for configuring the controls.

“The process at the Drying mill was good, but it required a lot of operator attention, even though the controls worked. The operator had to make constant interventions in the process to minimize the impact of variations and maintain the continuity of the process. Thus, the operator had difficulty monitoring the process as a whole, making his reports and managing his team”, analyzes Giovane.

Until getting to control the position of the sheet in the dryer, the team went through the creation of the moisture control and bottom dilution of the bleached pulp tower. “All these created controls provided a reduction in the oscillation gap of the controlled variables, generating greater stability for the process, contributing to the DCS Operator starting to operate less, becoming a process manager, also increasing its availability to manage the team”, notes the Drying Specialist.

ANDRITZ OPP specialist Heller Braga highlights that one of the premises of the work is precisely the constant optimization of the drying process and performance, applying multidisciplinary knowledge to advanced tools and innovation projects. “The objective is to get to the point of the application of the autonomous factory concept and that the person who currently occupies the role of panel operator becomes a process manager, evaluating and improving the decision-making suggestions of an intelligent system.”

Another important point for the success of the project is the timetable and alignment of activities, which was carried out with great professionalism by both parties, with several technical discussions for development and results achievement.  “We are reaching satisfactory results in the work carried out by the Eldorado and Metris OPP team together, such as better control of process variations, generating greater mill stability and efficiency. Through new controls, we intend to increasingly achieve operational excellence, generating greater productivity and safety in our mill”, summarizes Drying Manager, Julio Cesar Arsênio.

Team designs an increasingly smart industrial mill

Eldorado’s employee since the beginning of 2020, Gabriel Caldato affirms with conviction that it was possible to align the expectations and desired results in all the projects or revisions of the advanced controls that had the need for adjustments or improvement. “In the future, we intend to arrive not only at controls that seek to reduce process oscillations but also that can anticipate oscillations or disturbances, generating information, alerts or suggestions for the operation, always thinking about improving and facilitating the work”, projects Gabriel, Specialist in Innovation and Drying Technology.

This future project, according to Gabriel, could be through new controls, improvements to existing ones or even through the development of predictors, dedicated virtual sensors to solve deviations or existing problems. “Some studies have already been started along these lines, and we have already reaped some fruits, but we still have many studies and projects in this direction that are in preparation, in addition to those that have yet to be started”, he concludes.

The plan drawn up by Heller and Israel together with their colleagues from Eldorado is very clear and includes the continuous improvement of projects already implemented, optimization of production, optimization of steam pressure in drying aiming to increase production and application of soft sensors for grammage and moisture of the leaf on MS2.

From Francisco Brasil Mattiazzo's point of view, Innovation and Technology Manager, Eldorado Brasil is optimistic about the use of new technologies. According to the manager, opportunities to apply Metris OPP in the Biomass and Energy area are being evaluated, in addition to a complete review of controls in the Fiber Line and Caustification areas. “We are a company that seeks to be at the forefront in the use of the best technologies for process control and optimization, so any new technology that ANDRITZ presents will be evaluated by the Eldorado team. If gains are identified, the project will continue”, Francisco summarizes.