overall presentation on raw materials, processing and finishing

1. PAPER AND
PULP
INDUSTRIES
Shruthi
Soumya
Rishika
Anusha
Nikitha
Abhijna

4.  Paper has a rich, colourful history which has
spanned the world's geography and its cultures.
Tracing its development , offers us insight into
humanity's relentless imagination, creativity and
sometimes folly.
 Paper as we know it today comes from another
source - China.
 it wasn't until the 3rd century that the secret art
of papermaking began to creep out of China, first to
Vietnam and then Tibet. It was introduced in Korea
in the 4th century and spread to Japan in 6th.

5.  Papermaking spread slowly throughout Asia to Nepal
and later to India. It made its true push westward
in 751AD
 The birth of the modern paper and printing industry
is accredited to JOHANN GUTENBURG
 In Europe and America,in the 18th century the mass-
production of paper became a thriving industry
supplying huge volumes of paper for the production
of newspapers, books, magazines, paper bags, toilet
paper, money and a huge variety of other purposes -
including clothing, chimney's and even coffins!

6.  Papermaking today is a large, capital-intensive industry,
characterized by high-speed machines and complex systems of
control for manufacturing to close tolerances thousands of
products vital to education, communications, marketing, packaging,
construction, etc.
 Throughout the 19th century, pulp and paper was largely a domestic
industry, serving the gradually increasing needs
 With the 1960s came the greatest surge of expansion in the
industry since the 1920s, spurred by provincial governments’
eagerness for new industrial investment .
 Over the past 20 years the most significant development in the
industry's fibre requirements has been the tremendous increase in
the use of wood chips, reject lumber and other wood residues from
saw mills . Also, large areas of public forestland was made available
to obtain raw material from..

8.  These paper mills are manufacturing
industrial grades, cultural grades and other
specialty papers. The paper industry in India
could be classified into 3 categories
according to the raw material consumed.
 Wood based
 Agro based &
 Waste paper based

9.  The Indian Paper Industry is among the top 12 Global
players today, with an output of more than 13.5 Million
tonnes annual with an estimated turnover of Rs. 35000
Crores.
 Paper Industry in India is moving up with a strong
demand push and is in expansion mode to meet the
projected demand of 20 Million tonnes by 2020. Thus
paper industry in India is on the growth trajectory and is
expected to touch 8.5% GDP in the coming years.
Therefore, the growth of Industry will out span the
present growth rate of 6.5%.
 The average salary for a chemical engineer in the Indian
paper and pulp industry is around 7 l.p.a.

10.  The pulp and paper industry comprises
manufacturing enterprises that convert cellulose
fibre into a wide variety of pulps, papers and
paperboards. About 95% of their fibre comes from
wood from forests, the balance from wastepaper
and a very small quantity of linen and cotton rags.
 Wood is reduced to fibre by mechanical means or
by cooking in chemicals.
 The fibres are then mixed with water, adhering to
one another as the water is removed by pressure
and heat.
 This is the fundamental principle of papermaking.

13.  Ample supply
 Available to pulp mill throughout the year
 Should not deteriorate in storage
 High yield of quality fibre
 Capable of being collected and stored in a small
area and transported, if necessary at low cost
 Cost of conversion to paper must be low
 Quality of paper made must be competitive
 Must not have a higher priority use

14.  Fiber
softwood
hardwood
non wood fibres
recovered/recycled fibre
 Chemicals
 Energy
 water

15.  Softwood
 Contain more lignin than hardwoods
 Longer and coarser fibre than hardwoods
 Strength to withstand stretching and tearing
 Improves the runnability of paper on the machine.
 Greater amount of lignin means that more amount of chemicals and
energy
 Include coniferous and non coniferous woods .... E.g.: pine, spruce
etc..
 Hardwoods
 Provide Smooth surface
 Primarily used in the production of printing paper because short
fiber pulp improves the printing properties of paper
 E.g...... Acacia, lemon, gum, birch, eucalyptus, pinus, patula,
paper mulberry, rubber plant wood etc..

16.  Non wood fibres
 Annual crops: flax, kenaf, hemp etc.- often grown especially
for paper production
 agricultural residues: rye, wheat straw, bagasse, etc.. (
vegetable wastes, fruit pulp etc.. – newer alternatives being
researched on) - byproducts of crops grown for other uses
 Straw: rice, wheat, bagasse, barley, reeds, etc..
 Grasses and reeds: lemon, panni, Ulla, siru, munji,
Sabai grass, bamboo etc...
 ADVANTAGES OF NON WOOD FIBRES:
 Non wood fibers can reduce the amount of chemicals needed
for pulping as well as shorten time, thus saving energy.
 The high cellulose content of cotton linter (85% to 90%)
compared to that of wood (35% to 49% cellulose) and the
low lignin content of hemp (3%) make these non wood fibers
valuable for papermaking

17. List of materials Cellulose (%)
Lignin (%)
Wood
 Coniferous 40-45
26-34
 Deciduous 38-49
23-30
Non wood
 Rice Stalk 28-48
12-16
 Wheat straw 29-51
16-21
 Barley Stalk 31-45
Table shows that non
wood not just rich
with cellulose fibres
but the
composition of lignin
is also low. So, it is
easy to be degraded
and consumed short
period of time
compared to wood
fibres in chemical

18.  Recovered fibre (recycled paper)
 Grade determined by the process used in
manufacturing the virgin pulp when the paper
was first made and contaminants added to or
picked up by paper in recovery from solid
waste or recycle collection process
 Contaminants: ink, wax and clay coatings, non
fibre filler materials used in
paper, adhesives, tape, staples, pieces of
plastic, metal, dirt etc

19.  For chemical pulping:
 Sodium sulfite, carbonate, or hydroxide.
 In the kraft pulp process the active
cooking chemicals (white liquor) are sodium
hydroxide (NaOH) and sodium sulfide
(Na2S)

20.  Half of the wood raw material is utilized as chemical
pulp fiber. The other half is utilized as fuel for
electricity and heat generation. In fact, a pulp mill has
two main lines. Wood is turned into pulp on the fiber
line.
 Energy is produced on the chemical recovery line from
the wood material cooked in the liquor; the cooking
chemicals are recovered for reuse. In the chemical
recovery line, the black liquor is evaporated and
combusted in a recovery boiler, and the energy content
of the dissolved wood material is recovered as steam
and electricity.
 The chemical pulping process generates more energy
than it uses.

21.  Water is intricately associated with all the three stages of paper
production namely, pulp making, pulp processing, and paper/paper
board manufacturing, and their associated activities of cooking,
bleaching, and washing.
 With more than 17,000 gallons of water used for every ton of
pulp produced, the pulp and paper sector remains the largest user
of industrial process water in the U.S. and the second largest in
Europe.
 About 85 percent of the water consumed in the pulp and paper
industry is used only for processing, thus, leading to the
generation of large volumes of contaminated wastewater.
 It is also one of the largest producers of wastewater. The paper

22.  The largest paper producing countries like
China, US, Germany, Japan, Canada, use
predominantly wood.
 Bamboo is an ideal raw material. India is the
first country in the world to use bamboo as
the basic raw material for making paper.
 Bamboo and pulpable timber continue to be
the basic raw materials for the paper
industry in India.

23. ITC Limited – PSPD
 Water and energy consumption per ton of
paper produced:
 Water: averaging around 43kL
 Energy: averaging around 1027 kWh
 Raw material base:
 Wood: around 52%
 Imported pulp: around 27%
 Waste paper: around 21%

24. Tamil nadu newsprint and papers limited (TNPL)
 Water and energy consumption per ton of paper produced:
 Energy: 1522 kWh
 Water: 55kL
 Raw material base:
 Bagasse pulp: 55%
 Hardwood pulp:35%
 De-inked pulp: 10%
Century pulp and paper (Mumbai, Maharashtra)
 Water and energy consumption per ton of paper produced:
 Water: 57 kL
 Steam: 8.37 tons
 Power: 1291 kWh
 Raw material base:
 Wood, bagasse and recycled fibre

25. Rainbow papers limited ( Ahmadabad, Gujarat)
 Water and energy consumption per ton of paper produced:
 Water: 15 Kl
 Energy: 544 kWh
 Raw material base:
 Waste paper and ready pulp
Trident limited (dhaula, barnala, punjab)
 Water and energy consumption per ton of paper produced:
 Water: 48 kL
 Energy: 981 kWh
 Raw material base:
 Wheat straw as agro residue raw material for straw pulp –
(50-80%)
 Eucalyptus and veneer waste from plywood industries for
wood pulp -rest

27.  Paper pulp: groundwood, chemical, semi
chemical pulps- bleached or unbleached
 Reuse pulp: recycled or repulped paper
products like newspapers, paperboard
etc..mixed with new pulp
 Miscellaneous cellulose pulp:
straw, linen, cotton, jute, rags
 Speciality pulp: inorganic fibres such as
asbestos and glass

28.  For fillers, sizing and coating, finishing
processes
Inorganic:
 Clay, talc, titanium dioxide, zinc sulfide,
calcium carbonate, calcium sulphate, barium
sulphate, alum etc..
Organic:
 Rosin, glue, caesin, waxes, glycerol,
dyestuffs etc..

29.  Pulp can be divided into two principal types:
 chemical
 mechanical pulp.
 In fact there are more than two types of
pulp . Pulp from recovered paper poses a
different challenge for the papermaker as it
often has to be de-inked and other
contaminants removed.

30.  The two processes of mechanical pulping are stone
groundwood (fiber is torn from the side of short logs
with grindstones) and refiner groundwood (wood chips
are passed through disc refiners). Mechanical pulping
does not separate the cellulose fiber from the lignin in
the wood, while chemical pulping does.
 In chemimechanical pulping, the wood is softened with
chemicals before grinding. There is also a process called
thermomechanical pulping, where the wood is softened
with heat and then disc-refined under pressure.

32.  Chemical pulping uses chemicals to separate the cellulose from the
lignin. This creates pulps with different properties that can be used
for higher quality paper. The three types of chemical pulping are
Kraft, Sulfite, and semichemical.
 The Kraft process, also called the sulfate process, involves an
alkaline treatment with solutions of sodium sulfide and sodium
hydroxide. In 1987 Kraft pulping was 95% of the total chemical
pulping.
 Sulfite pulping began with the use of calcium as the sulfite liquor
base. Today the base has been changed to magnesium, ammonia, or
sodium. This allows for the recovery of spent liquor.
 The semichemical pulping process involves cooking wood chips in a
neutral solution of sodium sulfite and sodium carbonate or sodium
hydroxide. Only some of the lignin is removed, and then the pulp

36. DE -
BARKING
CHIPPING
DIGESTOR
SCREENING
WASHINGBLEACHING
DRIED /
BALED

38. Debarking is the process of
removing bark from wood. Debarking generally involves
the use of industrial machinery into which the log or
stake is placed. Generally they are powered by
hydraulic motors.

39. The wood chips are then cooked in pressurized vessels
called digesters. In a continuous digester, the materials
are fed at a rate which allows the pulping reaction to be
complete by the time the materials exit the reactor.
Digestion is done to remove the lignin and hemicellulose
content .
Wood chips + NaOh + Na2S -----
-> Black Liquor

40. • Steam from the hot slurry passing through the tank is
recovered. This steam is used for the preheating of
chips. This tank has high concentration of pulp slurry
• Reduces the pressure of steam from 80 to 10 atm
before entering the blow tank.

41. Screening of the pulp after pulping is a process
whereby the pulp is separated from
large shives, knots, dirt and other undigested residues.
The accept is the pulp. The material separated from
the pulp is called reject.
Cooking liquors are separated from the cellulose
fibers. Pulp washers use counter current flow
between the stages such that the pulp moves in
the opposite direction to the flow of washing

42. • Bleaching of wood pulp is the chemical
processing carried out on various types of wood
pulp to decrease the color of the pulp, so that it
becomes whiter.• Traditionally chlorine based
oxidizing agents were used for
this process but due to the
formation of dioxins and other
undesirable products, the usage
of chlorine has been
discontinued.
• In the modern and improved bleaching stage, hydrogen
peroxide is added along with sodium hydroxide, which

43. Lignin
content
decreases.

44. Q. WHY THIS PROCESS?
1. Pulp produced is stronger than that made by
other pulping processes.
2. Acidic sulfite processes degrade cellulose more than the
kraft process, which leads to weaker fibers.
3. Mechanical pulping processes leave most of the lignin in
the fibers.
4. The kraft process can use a wider range of fiber sources
than most other pulping processes.

46. •The black liquor (lignin-rich) produced
from the Sulfate pulp production
contains 95-98% of digested chemicals.
• To reduce air and water pollution and
to balance economy of operation, these
chemicals should be removed before
disposal.

49. • It is a series of single
effect evaporators of 5-6
stages of calandria
equipment followed by disk
evaporators .
• After the first step the
black liquor is about 20 -
30% solids. At this
concentration
the rosin soap rises to
the surface and is skimmed
off.
 . The weak black liquor is
further evaporated to 65%
or even 80% solids and

50. •Organic carbon burns in
smelting furnace , supplying
necessary heat and CO2 .
• The combustion is carried
out such that sodium
sulphate is reduced to
sodium sulphide by the
reaction :
NaR(lignin salt) +air
Na2CO3 + CO2

51. •Molten slag is
produced
• Here organic
carbon present in
black liquor is
burned.
• High pressure 28
atm to 30atm steam
is produced.
•The reaction that
takes place inside
furnace is :
Na2SO4 + 2C-----

52.  The molten salts from the recovery
boiler are dissolved in a process
water known as weak wash.
 This process water, also known as
weak white liquor is composed of all
liquors used to wash lime mud
and green liquor precipitates. The
resulting solution of sodium
carbonate and sodium sulphide is
known as "green liquor .
 This liquid is mixed with calcium
oxide , which becomes calcium
hydroxide in solution, to regenerate
the white liquor used in the pulping
process through an equilibrium
reaction :
Na2S + Na2CO3 + Ca(OH)2 ←→
Na S + 2 NaOH + CaCO

53.  A clarifier is
used as a
filter to
remove solid
particulates or
suspended
solids from
liquid
 It separates
as filtrate and
sludge .
 Filtering
medium is
monel metal .

54.  Impurities
are washed
away in this
tank after
clarifying.

55.  Calcium
carbonate precipitates from
the white liquor and is
recovered and heated in
a lime kiln where it is
converted to calcium
oxide (lime):
 CaCO3 → CaO + CO2
 Calcium oxide (lime) is reacted
with water to regenerate the
calcium hydroxide used in
reaction :
 CaO + H2O → Ca(OH)2
 It precipitates lime mud.
Carbonate is causticized by
adding Ca(OH)2 .

56. An Overview

57.  Definition
 ‘ fourdrinier ‘ method of
production
 Finishing
 Chemical additives

58. Paper is a thin material produced by pressing
together moist fibers- cellulose pulp , derived
from wood, rags or grasses, and drying them
into flexible sheets.
Basic raw materials include-
Fibrous : containing groundwood, paper products
(recycled) , asbestos and glass
Non-Fibrous: clay, talc ,glue , waxes , glycerol
,titanium dioxide , zinc sulfide , calcium
carbonate

59. Modern papermaking began in the early 1800s in Europe with
the development of the Fourdrinier machine, which produces a
continuous roll of paper rather than individual sheets. These
machines have become very large, up to 500 feet in length,
producing a sheet 400 inches wide, and operating at speeds of
The Fourdrinier press

60. The Fourdrinier machine is made of four
sections – Forming Section or Wet End, Wet
Press Section, Dryer Section and Calendar
Section.

61. 1.Headbox
2.Press Roll
3.Forming Board
4.Wire
5.Suction Boxes
6.Suction Couch Roll
7.Wire Driving Roll

62. Headbox
Because wood pulp fiber has a strong
tendency to clump, it needs to start off
with a very high percentage of water
content, allowing the pulp to have an even
distribution, the slurry (or furnish) held in
the Headbox which contains around 99%
water.
Rollers
The furnish travels down the Slice onto
the revolving Wire at the Breast Roller
point of contact and then over a series
of relatively small, parallel rolls of steel
or brass tubing called "table rolls." It
then passes over several suction boxes,
under a roll covered with woven or parallel
wires, called a "dandy roll," and over one

63. Forming board
device found under the wire on Fourdinier paper machines, just after
the headbox; used to prevent premature removal of too much water
during sheet formation.
Wire
Fine mesh polyester fabric on which the paper sheet is formed by
stock draining through it
Suction boxes
aka ‘Uhle Box’ is found in the press section; used to remove water
and detergents from the press felts.
Suction couch rolls
Suction rollers hold the furnish to the mesh and help remove the water
content. By the time the paper or web has reached the Wet Press

64. The Wet Press Section carries the wet web between a series of
rollers under high pressure to squeeze more water from the paper,
much like a mangle. The Felts (polymeric fabrics) support the web and
also aid water removal by absorption. As the web enters the third
section the paper web consistency can be as high as 40%.
Wet web strength factors-
 Fiber lengths
 Moisture content
 Latency(kinked,curled fibers)
 Inter fiber friction (affected by refining , surfactants )
 Surface tension
 Process variations

65. Steam heated rollers in the Dryer Section cause further water
removal through evaporation . It is in the Dryer Section that the
web will be treated with Sizing to change the characteristics of
the paper and via a coating unit, the surface will be covered with
calcium carbonate or china clay for coated papers such as gloss,
silks and velvet types. The stock is usually about 95% solids by the
time it comes off the last dryers.

66. Calendering
 A calender is a device with two or
more rollers through which the paper is
run. The compression of the rollers and
the application of heat give the paper
its smooth and glossy properties. It
also gives it a more uniform thickness.
The pressure applied to the web by
the rollers determines the finish of
the paper.
 After calendering, the web has a
moisture content of about 6%
(depending on the furnish). It is wound
onto a roll called a tambour or reel,
and stored for final
cutting and shipping

67. • Coating
Coating improves the opacity, lightness, surface smoothness,
lustre and color-absorption ability of paper.
Coating means that a layer is applied to the paper, either
directly in the papermaking machine or separately.
Varieties of coated paper range from pigmented to cast-
coated.
The coat consists of a mix of pigments, extenders such as
china clay and chalk, and binders such as starch or latex.
In addition, various chemicals are added to give the paper
the desired characteristics.

68. Why do we need to add additives?

Improves fiber to fiber bonding

Retain fiber & fines, giving better yield from
the same raw material

Better glaze & stiffness

Increase in breaking length, double fold, tear
factor & other strength properties w.r.t.
writing / printing paper industry.

Improves the formation of paper and fiber
distribution

69.  Wet strength additive : ensures that the paper retains its
strength when wet. Very important for making tissue papers.
Chemicals used are urea formaldehyde ,poly-
amines
 Dry strength additive : chemicals which enhance the strength of
the paper at its normal condition. includes compression
strength, bursting strength, tensile breaking strength etc. Typical
chemicals used are as cationic starch and polyacrylamide (PAM)
derivatives--acts as binder of fibers
 Colorants : Basically used to give the paper a specific color,
improving the tone of the paper at the same time.
 Optical brightening agents: makes paper more white by
absorbing UV light from fluorescence and re-emits in the blue
region

71.  Paper can be produced with a wide variety of properties, depending on
its intended use.
 For representing value: paper money, bank
note, cheque, security , voucher and ticket
 For storing information: book, notebook, magazine, news paper, art &
letters.
 For communication: between individuals and/or groups of people.
 For packaging: corrugated box, paper bag, envelope, Packing & Wrapping
Paper, and wallpaper.
 For cleaning: toilet paper, handkerchiefs, paper towels and facial tissue
 For construction: papier-mâché, origami, paper planes, quilling, paper
honeycomb, used as a core material in composite materials, paper
engineering, construction paper and paper clothing
 For other uses: emery paper, sandpaper, blotting paper, litmus
paper, universal indicator paper, paper chromatography, electrical
insulation paper (see also dielectric and permittivity) and filter paper

73. Recycling 1 tonne of paper :
1.Saves approximately 17 trees.
2.Don’t use approximately 380 gallons
of oil.
3.Saves 4000KW of power.
4.Saves 3 cubic yards of landfill space.
5.7000 galloons of water.