Paper Chemicals  
  The paper industry uses polymers in a wide variety of application :
   
 
The treatment debarking water and of green liquor ,retention, dewatering , the treatment of statics, the treatment of ultra fines ,the treatment of water & sludge.

The use of polymer allows the industry -the largest polymer of process water –to reduce water consumption increase its equipment productivity and improve validity of the paper and reduce its impact on the environment .
   
  The main application & polymers involved are :
   
 
Retention of fillers (titanium oxide, kaolin, calcium carbonate etc,) in the paper.

The polymer is introduced at the head box of the paper machine in order to flocculate the fibres and filters. This flocculation allows better retention of the filters within sheet .The operation can also be carried out by combining the polymers with micro particulate systems (silica ,bentonite etc)
   
  The polymer used are anionic or cationic polyacrylamides ,depending on the characteristic of the processes involved .
   
 
Dewatering :polymer are used to increase the speed of board machine and the production rate by improving the dewatering operation at the wet end ,and therefore improving the drying operation.

The recovery of fibres using moderately or highly charged cationic polymer.

Increase in the dry strength by adding ,for example ,low molecular –weight polymers with a low cationic charge.

Temporary wet strength increase in the wet web ,for example using glyoxalated polyacrylamides.

The treatment of anionic impurities (pitch) in the paper ,using poly DADMAC or Polyamines.

  The treatment of factory feed water ,waste water and residual sludge using various polymer described in the corresponding paragraphs.

  Clarification of waste paper de-inking ,with treatment of the water produced using ,for example , coagulant followed by a molecular –weight flocculants

  The fixation of dyes on the fibres

  Finally ,the cationization of AKD type sizing agents.