Customer case:

Mitsubishi Hachinohe optimizes recovery boiler performance

Apr 13, 2023

Mitsubishi Paper Hachinohe Mill, located in Hachinohe City, Aomori Prefecture, Japan, is Mitsubishi Paper Mills Ltd’s main mill. It produces 500,000 tons of fine paper and writing paper annually. In June 2019, a Valmet Recovery Liquor Analyzer (Valmet Alkali R) with an advanced process control (APC) application, Valmet Recovery Boiler Optimizer, were started up in the mill’s chemical recovery process. Along with improving recovery boiler efficiency, Mitsubishi Hachinohe Mill combats climate change through accurate online analyses and optimization.

Mitsubishi Hachinohe optimizes recovery boiler performance with Valmet Alkali R and APC
We selected Valmet because the company has a proven track record, and we could expect a high improvement effect through the additional analyses provided. Valmet did exactly what we expected them to do, including startup and subsequent tuning. Valmet people responded promptly to our operational consultations and requests.

Optimization of the energy balance throughout the plant, lower costs through energy savings and efficient chemical recovery are the main factors for us papermakers to stay competitive. We need business partners that have the know-how and experience to achieve these goals. We appreciate that they can provide appropriate advice and support us.

We are looking forward to Valmet providing us with products and services that can contribute to our process improvement, energy savings and decarbonization through the use of digital transformation.
Mitsuhiko Chiura, Raw Material Department Group Leader at Mitsubishi Hachinohe

Summary

Location Mitsubishi Paper Hachinohe Mill, Japan
Customer challenge
  • Although the mill made some combustion improvement efforts in the past, overall air volume control had not yet been achieved, and the boiler was operating with excessive air volume.
  • Needs for better combustion to help increase steam production, reduce the amount of sootblowing steam consumption, and eventually decrease the use of fossil fuels.
Solution

Valmet Recovery Liquor Analyzer (Valmet Alkali R)

Valmet Advanced Process Control (Valmet APC) 

Valmet Recovery Boiler Optimizer

Results
  • O2 variation was reduced by 78%
  • Increased reduction efficiency to 94.8%
  • Sootblowing steam consumption was lowered by 7.5%
  • Improved recovery boiler reduction performance
  • Improved combustion
  • Reduced heat loss through smelt
  • Controls for black liquor burning, air feeding, and furnace processes
Keywords Pulping and fiber, Asia Pacific, Automation