Title:
クラフト法パルプ製造プロセスにおける薬品回収方法
Document Type and Number:
Japanese Patent JP4230612
Kind Code:
B2
Abstract:
In a process for producing kraft pulp, the process is made closed, the yield of pulp is improved and environmental problems are minimized. An alkaline solution containing Na2S which flows in a process of producing kraft pulp, is electrolyzed by an electrolytic oxidation method; a liquid which is formed at an anode side and contains a polysulfide type sulfur in an amount of 6 g/ l or more, is added, as it is or after being causticized, to the process before a chip has the maximum temperature, and a NaOH solution formed at a cathode side, is added to at least one step of the process after the chip has the maximum temperature till a final bleaching stage; and at least chemicals in the step wherein NaOH is added, among chemicals discharged in all steps from a cooking step till the final bleaching stage, are recovered and reused.
Inventors:
Keigo Watanabe
Yasunori Minamisato
Kazuaki Sakai
Tatsuya Ando
Makoto Nakao
Yasunori Minamisato
Kazuaki Sakai
Tatsuya Ando
Makoto Nakao
Application Number:
JP15035499A
Publication Date:
February 25, 2009
Filing Date:
May 28, 1999
Export Citation:
Assignee:
NIPPON PAPER INDUSTRIES CO.,LTD.
Kawasaki Chemical Industry Co., Ltd.
Kawasaki Chemical Industry Co., Ltd.
International Classes:
D21C11/04; D21C3/02; D21C11/00
Domestic Patent References:
| JP8512099A | ||||
| JP8311790A | ||||
| JP8504005A | ||||
| JP5215602A |
Foreign References:
| WO1997041295A1 |
Attorney, Agent or Firm:
Hirokuni Kamo
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