With today’s progressively high energy and costs of chemical and stringent environmental guidelines, the need for better-quality recovery of paper chemicals from the pulp and paper creation process has developed into an important economic factor. It is vital that mills make the most of steam and power making capacity, decrease recirculating chemical loads, and lessen chemical losses.

Paper is an outcome from the forest, used in numerous forms. This different paper form is made by pulping of wood, bleaching pulped wood, dispersal of these bleached pulps into sheets eventually altering it to paper. With diverse designing stages of the paper, numerous substances are employed to give paper its present properties like the bleaching chemicals making paper white.
Kraft pulping is the key pulping procedure was developed in Germany in 1884 and is a dominating technology today also. Kraft pulping frequently relies on a mixture of heat, paper chemicals and mechanical pulping for converting wood into a smooth, soft pulp appropriate in papermaking.

Functions of Kraft pulping process
• Minimizing the ecological impact of waste material from the pulping procedure.
• Reprocessing pulping chemicals, Na2S and NaOH;
• Co-generating power and steam.
For every ton produced, the Kraft pulping process makes about ten times more tons of liquid or dry solids further treated through the process of chemical recovery. This making of black liquor in large quantity makes it the fifth most important fuel, accompanied by oil, coal, natural gas, and petroleum. As black liquor is fashioned from wood, it is one among the bio-fuel.
Advantages for Chemical Recovery Process:
• It can be employed with almost all species of wood.
• It can effortlessly handle the extractives in most cone-bearing wood
• The pulp has a decent amount of strength.
• The recovery procedure for the chemicals is well established.
• More operative at eliminating impurities like resins
This conventional Kraft Pulping procedure has experienced many changes and it will have many opportunities. One of the recent trends is:
Gasification
Expansions in the process of chemical recovery, has presented gasification of black liquor which demonstrates to be a possible auxiliary for recovery boilers. Black liquor gasifies with this competence are still in the growth stage and implementation on a full-scale is still an innovative approach.

The dependability and competence of lime kilns, evaporators, recovery boilers and causticizing plants and have a straight impact on the amount and superiority of white liquor, and eventually the amount and eminence of pulp that is produced by Kraft mills. The utmost prospect for growing energy and efficiency of chemical recovery and for improving inclusive working performance at present Kraft pulp mills is via cutting-edge energy incorporation and mill-wide control.