Lignin is an aromatic complex polymer of monolignols (aromatic alcohols) which is found in plant cell walls. Later than cellulose, lignin is the most abundant natural polymer in the planet. It is not composed of carbohydrate monomers whereas the rest of polymers found in plant cell Read more
Globally, there are several bleaching sequences are shown in different pulp mills to achieve the bleaching action. Different chemicals are used in each stage usually with washing between two stages to removes products. The preference of bleaching sequences depends on many things such Read more
The objective of pulp bleaching is to produce white pulp. Unbleached pulps are not suitable for manufacturing of high grade of white paper. Since all the processing pulp brightness is very low, especially Kraft pulp. The sulfite pulping process produces comparatively bright chemical pulps, while Read more
Screening equipment is the important operational system for pulp processing. After separation of the black liquor from the fiber in the washing section the pulp contains coarser fibers, foreign matter and dirt as like pieces of bark, digester brick, cement etc. Hence this unwanted and troublesome Read more
There are different methods are available for pulp washing such as rotary vacuum washer, rotary pressure washer, pressure and atmospheric diffusion washers, horizontal belt washer and dilution/extraction equipment. Among them the rotary vacuum washer method is well-known to paper makers for long Read more
Sulfate or Kraft pulp is one of the chemical pulping processes. It is manufactured by alkaline method. Kraft pulping process is the dominating pulp manufacturing process in the world. Today this process is most widely used with a production of 70-80% of the total Pulp.
Although soft Read more
What is the tensile strength of paper?
The tensile strength is the maximum stress to break a strip of paper sheet. It is one of the most important basic physical properties of paper and paperboard. The tensile strength is different basis on fiber direction. Since the fiber orientation is Read more
What is the tear strength of paper?
The tear strength of paper means the resistance of a paper sheet to tearing force that it is subjected to. It is another important basic physical property of paper and paperboard. It is measured in both machine direction (MD) & cross direction (CD) and Read more
The caliper or thickness is one of the important basic physical properties of paper and paperboard. It is depends on refined stock, category of fiber, dryer temperature, load on press section and calendars, moister content, filler etc for a given basis weight. Thickness is related to bulk or Read more
The basis weight or grammage is basic physical property of paper and paperboard. The Basis weight of paper is calculating by the weight per unit area. It is mainly expressed as GSM (grams per square meter) and pounds per ream (500 sheets) of a specific size. It is also expressed in kg/m2, pounds Read more