Unlike traditional large-scale petrochemical manufacturers who focus on a single product, polymer manufacturers manufacture many products under a wide range of conditions. Operating a polymer reactor to meet these varying specifications is a complex nonlinear control problem. Therefore, operations must focus not only on maintaining the quality of each product under “quality level” conditions, but also on transitioning from one quality to another in the fastest and most efficient manner. the most economical. To maximize production and profits throughout the production lifecycle, manufacturers must continuously monitor the many variables that influence product quality and production rate.
This article will present a case study of a chemicals manufacturer – one of the largest integrated energy companies in the world. Its polyethylene business unit is a leading producer of polyethylene with a full range of low density polyethylene (LDPE) and linear low density polyethylene (LLDPE) products for the packaging, agriculture, goods industries. consumption and construction. The company’s European unit manufactures a wide range of product grades and produces hundreds of thousands of kilotons of LLDPE per year, using its proprietary process to produce the chemical. The customer needed a way to meet specific production goals, including increasing LLDPE production, reducing out-of-specification materials, and reducing transition times between grades.
The company learned about Rockwell Automation’s advanced process control (APC) solutions during a technical exchange meeting and was impressed with the company’s proven expertise in the polymer industry. Finding that Rockwell Automation solutions could help the company meet its quality and production goals, the company implemented the Rockwell Automation FactoryTalk Analytics MPC solution.
FactoryTalk Analytics combines steady-state optimization with closed-loop predictive control to reduce product variability and transition times, improve reactor stability, and maximize feedstock efficiency.
The client’s specific requirements for the software included controlling the composition of the gas phase in the reactor and the instant management and control of the reactor product quality and the transitions between grades. FactoryTalk Analytics creates online predictive models that augment hardware instrumentation and lab analysis to provide real-time estimates of process and product conditions. These virtual instruments provide the feedback and predictive process information needed to keep production on track and avoid process disruptions, identifying problems and providing responses quickly – without the time and expense of ‘additional laboratory analyzes. Customer specific requirements were to monitor key quality variables such as hot melt flow index (MFI) and density from actual reactor data.
The first Rockwell Automation solution was installed, implemented, tested and commissioned at the customer site within 8 months. Rockwell Automation provided most of the engineering expertise with the support of customer staff, who were trained during the execution of the project.
The benefits of the Rockwell Automation solution, including significant improvements in production levels, reduced disruption, reduced reactor variation, and savings in transition times, were quickly evident to the customer. The customer also reduced variability in product properties by 50% with the implementation of Rockwell Automation software. “From there, we could operate closer to our hardware constraints, which resulted in higher throughput,” said a customer representative. The software also reduced transition times by up to 50% (depending on the quality of LLDPE produced), increased production by 7% and increased efficiency in the use of monomers and catalysts.
According to the customer’s representative, the project was successful and brought additional benefits, which improved the profitability of the plant by increasing the range of options.
A customer representative said, “We have achieved non-APC improvements through a new understanding of system constraints. For me, one of the most notable improvements is the ability to perform new level transitions that weren’t possible with the old control scheme. This gives us greater flexibility to respond to the needs of our customers.
Based on the success of the project, Rockwell Automation and the customer have formed a strategic alliance to deploy Rockwell Automation’s advanced process control solutions at the customer’s polyethylene facilities, joint ventures and licensees around the world. In the first two years of the alliance, the customer and its affiliates successfully deployed 14 projects with Rockwell Automation.
Read the article online at: https://www.hydrocarbonengineering.com/special-reports/29092021/reduce-cycle-time-to-production/