Metsä-Botnia Kaskinen, Finland
In early 80’s, then new, Metsä-Botnia Kaskinen Pulp Mill had cracks in their impregnation vessel caused by stress corrosion. There was a threat of immediate close-down based on the pressure vessel code.
Instead, Savcor suggested a new electrochemical solution, Anodic Protection, for the remedy first time to be tested in a Finnish pulp mill. The protected vessel remained operative until the mill was closed in 2009, a healthy 25-year lifetime extension with minimal maintenance costs.
Soporcel, Figueira da Foz, Portugal
In late 80’s, the Soporcel, Figueira da Foz Pulp Mill (now Navigator Co.) in Portugal had severe cracking in their impregnation vessel of the pulp digesting process caused by stress corrosion. Again, there was an imminent threat of banning the vessel from use. This time Savcor had a ready and tested solution, Anodic Protection. The system had its third control system update in 2017, 30 years after the AP installation.
Metsä-Fibre Oy, Kemi, Finland
In 2002 Oy Metsä-Botnia Ab (now Metsä Fibre Oy) Kemi’s pulp mill decided to change its pulping process to the modified cooking. Prior to the process change, it was recognized that the modified process conditions pose a very significant corrosion risk. Because of this it was decided to install the Savcor Anodic Protection System to the digester to prevent corrosion. In 2018, Anodic Protection with Savcor’s monitoring service has been in operation for 16 years. It has protected the digester against corrosion and significantly reduced the maintenance costs.
Daishowa Paper Co, Fuji City, Japan
Daishowa Paper Co. ordered Savcor CP to protect their bleaching filters in 1991. After the installation, more than 90% reduction in the corrosion rates was measured by Daishowa. The main savings came from the cutting of the maintenance costs and especially due to the related down-time.
Bahia Sul (now Suzano Mucuri), Brazil
In 1994 Bahia Sul in Brazil (now Suzano Mucuri) installed Savcor Anodic Protection in their digester, then one of the largest in the world, to counteract the measured corrosion rate as high as 2.5 mm/year. The installation was successfully completed in only 38 hours, a significant reduction from two weeks required by other repair methods. This meant vast gains in production when the down-time was minimized. Afterwards a 95% reduction in corrosion rate was reported by the mill.
Cenibra Mill, Brazil
Cenibra digester was started up in 1975. In 2000 the new cooking process increased the production up to 1400 t/d. The new process activated corrosion which reached a speed of up to 5 mm/a. Corrosion took place as general thinning and stress corrosion cracking. In 2003 the Savcor Anodic Protection was installed and corrosion stopped. Currently the mill continues with the modern process and with the Savcor AP without any corrosion risks.
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