02 Major Progress in Decarbonization
Advanced Control Technology to TOX Process
Advanced energy conservation in processes
that account for approximately 70% of CO2

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Toward decarbonization , we have succeeded in introducing Advanced Control Technology (referred to as ACT) into the TOX process (part of POM manufacturing) at the Fuji Plant, which was considered difficult in the past. This technology can significantly reduce CO2 emissions and contribute greatly to the realization of a decarbonized society. Going forward, we plan to introduce this technology to our overseas plants.

Focusing on TOX Process
Successful quantitative modeling of conventional operations

Manufacturing processes at chemical plants consume considerable quantities of energy.
To achieve significant reductions in CO2 emissions, it is vital to cut back on this energy consumption.
In particular, the POM TOX process accounts for approximately 70% of the total CO2 emissions from the Fuji Plant, therefore, there was a need for technological innovation in this process.

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Challenges for TOX Process

A TOX processing plant is a complex structure with multiple distillation columns, which makes overall optimization extremely challenging. To introduce ACT into the TOX process, we needed to quantitatively model the relationship between product quality and a huge volume of numerical data on such factors as pressure and flow rate, data that was previously qualitatively managed by operators based on their experience and expertise.
To realize more advanced production, we launched the Fuji Plant Restructuring Project in 2018 and incorporated “Production Innovations by the Daicel Way” in 2021.

In this approach, we improved and stabilized the plant infrastructure by visualizing plant issues. As a result, the foundation for introducing ACT was prepared, making it possible to ensure product quality above a certain level. This approach enabled us to introduce ACT even under a complex structure. Reducing variations in quality also enabled us to achieve more optimal operation than ever before, contributing to significant energy savings.
Soft sensors that predict material composition after TOX distillation are also required in ACT. By quantitatively modeling the relationship between process data, such as pressure, and product quality, we were able to build a new soft sensor and make it possible to predict composition with a high degree of accuracy.

What Is Advanced Control Technology?

It is a technology that models and predicts the relationship between each process variable such as temperature and pressure and product quality using simple formulas and that simultaneously controls and optimizes process variables to prevent quality fluctuations. In a complex process spanning multiple distillation columns, it is difficult for operators to simultaneously track and control every aspect, so optimization through ACT is very effective.

The Fuji Plant Restructuring Project

CO2 Emissions Reduced Approximately 4,500 Tons per Year

By introducing ACT at the Fuji Plant, we successfully cut overall CO2 emissions by 4,500 tons annually and steam emissions by 34,000 tons annually. This was not only due to the reduction in energy usage in the TOX process.
ACT has also stabilized quality and reduced off-spec products, resulting in a significant reduction in the energy required to restart machines. As a side effect, the burden on operators has been greatly reduced by automating the operation control that was previously manual.

Further Evolution in ACT
and Expansion to Overseas Plants

Along with the shift to green energy, demand is constantly growing for ever more advanced energy conservation.
Going forward, based on the technological knowledge cultivated at the Fuji Plant, we will continuously expand ACT to our overseas TOX processing plants and swiftly introduce decarbonization technology at Group companies.
We will expand our Group-wide environmental load reduction efforts to achieve decarbonization through our products and services.