The Bioresource Development Center’s Wood Refinery Section is focused on introducing cutting-edge continuous process technology into the pulping equipment at Oji Paper Co., Ltd.’s Yonago Mill, developing dissolving pulps suitable for various applications, and developing biochemical materials using hemicellulose.
1) What is Dissolving Pulp?
Dissolving pulp is a high purity cellulose pulp made from wood that has had the maximum possible amounts of hemicellulose and lignin removed. It is primarily used as a cellulose material for industry.
2) Applications of Dissolving Pulp
Dissolving pulp can be processed for various applications.
・Once dissolved, dissolving pulp can be separated out and used as regenerated cellulose
⇒Rayon, cellophane, etc.
・By hydrolyzing the non-crystallized parts of the cellulose, it can be used as crystalline cellulose
⇒Medicines, food additives, etc.
・It can be used as various cellulose derivatives
⇒Food additives, civil engineering materials, synthetic textiles, etc.
Different applications require DP with different levels of cellulose purity and degrees of polymerization, and advanced technology is needed to achieve this differentiation. The Bioresource Development Center’s Wood Refinery Section creates the baseline designs for dissolving pulp manufacturing conditions and develops the underlying technology for producing high-quality DP suitable for various applications.
DP manufacturing at Oji Paper Co., Ltd.’s Yonago Mill started in May 2014, and it is sold through Oji Green Resources Co., Ltd.
To the Oji Green Resources Co. Ltd. website
Manufacturing Dissolving Pulp and Effective Use of Prehydrolysis Solution
1) Manufacturing Dissolving Pulp
Oji’s dissolving pulp starts as eucalyptus wood chips and undergoes a prehydrolysis process using hot water, which breaks down the hemicellulose and removes it. The wood chips are turned into pulp by the Kraft Process and then bleached.
Dissolving pulp’s cellulose purity is primarily decided by the conditions of prehydrolysis, and its degree of cellulose polymerization is primarily decided by the conditions in the Kraft Process. By controlling these conditions, dissolving pulp can be manufactured for a variety of applications.
2) Effective Use of Prehydrolysis Solution (Hemicellulose)
The prehydrolysis solution produced by the dissolving pulp manufacturing process is primarily composed of xylo-oligosaccharides, and includes xylose, other monosaccharides and various organic acids such as acetic acid and formic acid.
At the Bioresource Development Center’s Wood Refinery Section, there is also a verification testing plant located beside the dissolving pulp plant which is engaged in converting prehydrolysis solution into other valuable materials. It is currently exploring the viability of manufacturing furfural and other materials, and the viability of manufacturing valuable materials from sugars.
Simultaneous Manufacturing of Dissolving Pulp and Furfural, etc.
Verification testing plant for DP and furfural manufacturing
(located inside Oji Paper Co. Ltd.’s Yonago Mill)