中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

32 records (took 0.021 seconds)

    11.
    发明专利
    未知

    公开(公告)号：FR2461777A1

    公开(公告)日：1981-02-06

    申请号：FR8008322

    申请日：1980-04-14

    Applicant: DEGUSSA

    Inventor： BERNDT WILHELM ,  JUNKERMANN HELMUT ,  KRUGER HORST ,  HAFNER VOLKER ,  WINK JAKOB

    IPC: D21C11/08

    Abstract: The highly odorous evaporation condensates arising in the recovery of chemicals in pulp digestion are completely deodorized by addition of hydrogen peroxide alone, i.e. without addition of a metal salt as activator, and can immediately be used either as washing water in the processing of the digestion waste liquors for chemicals recovery or discharged directly into a watercourse.

    12.
    发明专利
    未知

    公开(公告)号：NO155499B

    公开(公告)日：1986-12-29

    申请号：NO810057

    申请日：1981-01-09

    Applicant: DEGUSSA

    Inventor： KRUEGER HORST ,  BERNDT WILHELM ,  SUESS HANS ULRICH

    IPC: D21C9/16

    Abstract: Cellulose is bleached by means of an organic peracid in the acid region and subsequently by means of peroxide in the alkaline region. As peracid there is employed an acid which is produced from the corresponding carboxylic acid by reaction with hydrogen peroxide in the presence of a mineral acid. The peroxide bleaching step which follows the peracid bleaching step is carried out after there is added the necessary amount of aqueous alkali solution for carrying out the peroxide bleaching step of the pulp without intermediate washing of the cellulose. A further addition of peroxide is not carried out.

    16.
    发明专利
    未知

    公开(公告)号：DK146163C

    公开(公告)日：1983-12-05

    申请号：DK128274

    申请日：1974-03-08

    Applicant: DEGUSSA

    Inventor： BERNDT WILHELM

    IPC: D21C5/02

    19.
    发明专利
    未知

    公开(公告)号：FR2436846A1

    公开(公告)日：1980-04-18

    申请号：FR7917876

    申请日：1979-07-10

    Applicant: DEGUSSA

    Inventor： KRUGER HORST ,  BERNDT WILHELM ,  SUSS HANS ULRICH

    IPC: D21C9/10

    Abstract: The process comprises at least three stages, the pulp being bleached in the first and third stages with a per compound and in the intervening second stage with chlorite. In particular for bleaching hard pulp, the latter can be subjected to a pretreatment with magnesium salts and/or organic complex formers. In the case of pulps which are difficult to bleach, or for regulating the degree of polymerisation, the process can be followed by further known bleaching stages. Between the first and second bleaching stages and any further bleaching stages following the process, washing with water is advantageously carried out. Washing between the second and third bleaching stages can be omitted. The process is suitable for bleaching all known pulp types, gives improved whiteness coupled with increased yield and allows substantial reduction in the present corrosion problems. Due to the reduced quantity of chlorite used, the process operates almost chlorine-free, and no significant quantities of chlorine pass into the effluent system.

Patent Agency Ranking