Chemical pulp treatment compositions and methods

Abstract

The present invention relates to compositions and methods for treating pitch problems in chemical pulp by treating chemical pulp process water with a combination of a lipase and a peroxide source. The present invention also relates to compositions and methods for treating pitch problems in chemical pulp by treating chemical pulp process water with a lipase, a peroxide source and organic acid(s).

1 . A method for reducing pitch problems in a chemical pulp, comprising treating a chemical pulp with a lipase and a peroxide source in amount effective to reduce pitch problems. 
   
   
       2 . The method of  claim 1 , wherein said treating is performed before, after or in between bleaching stages. 
   
   
       3 . The method of  claim 1 , wherein said chemical pulp is a Kraft pulp. 
   
   
       4 . The method of  claim 1 , wherein said chemical pulp is a sulfite pulp. 
   
   
       5 . The method of  claim 1 , wherein said chemical pulp is bleached Kraft pulp. 
   
   
       6 . The method of  claim 1 , further comprising the step of preparing paper, linerboard, corrugated paperboard, tissue, towels, corrugated containers or boxes from said pulp. 
   
   
       7 . The method of  claim 1 , wherein said lipase is derived from a strain of  Aspergillus , a strain of  Achromobacter , a strain of  Bacillus , a strain of  Candida , a strain of  Chromobacter , a strain of  Fusarium , a strain of  Humicola , a strain of  Hyphozyma , a strain of  Pseudomonas , a strain of  Rhizomucor , a strain of  Rhizopus , or a strain of  Thermomyces.    
   
   
       8 . The method of  claim 1 , wherein said lipase is derived from a strain of  Candida.    
   
   
       9 . The method of  claim 1 , wherein said lipase is derived from a strain of  Candida antarctica  lipase A or the  Candida antarctica  lipase B. 
   
   
       10 . The method of  claim 1 , comprising treating a chemical pulp with a lipase, a peroxide source and an organic acid. 
   
   
       11 . The method of  claim 1 , wherein peroxide source is hydrogen peroxide. 
   
   
       12 . The method of  claim 1 , wherein peroxide source is a precursor of hydrogen peroxide. 
   
   
       13 . The method of  claim 12 , wherein the precursor of hydrogen peroxide is perborate or a percarbonate. 
   
   
       14 . The method of  claim 1  wherein the peroxide source is an enzyme that converts molecular oxygen and an organic or inorganic substrate into hydrogen peroxide. 
   
   
       15 - 16 . (canceled)