[Topic 7] Pulp and Paper Industry

Question 1

Main structural polysaccharide of the plant cell wall.

Answer 1

Cellulose [(C6H5O10)n]

Question 2

Made from fibrous material and usually in thin flat sheets.

Answer 2

Paper

Question 3

A plant source for papyrus

Answer 3

Cyperus papyrus

Question 4

Inventor of the printing press

Answer 4

Johaness Gutenberg

Question 5

Three main types of pulp processing (3)

Answer 5

1. Chemical
2. Semi-chemical
3. Mechanical/Thermomechanical

Question 6

Raw materials for pulp processing (3)

Answer 6

1. Wood fibers
2. Cotton and linen rags
3. Other applicable fibrous material

Question 7

Soft wood

Answer 7

coniferous

Question 8

Hard wood

Answer 8

deciduous

Question 9

Conversion of wood into mass of liberated fibers

Answer 9

Pulping

Question 10

Types of chemical pulping (3)

Answer 10

1. Kraft (Sulfate) Process
2. Soda Process
3. Sulfite Process

Question 11

meaning of the german word kraft

Answer 11

Strong

Question 12

uses Na2SO4 and NaOH to pulp wood and can produce odoriferous chemicals during liquor cooking.

Answer 12

Kraft (Sulfate) Process

Question 13

Is an essential factor of the Kraft Process

Answer 13

Black (spent) liquor recovery

Question 14

True or false: Kraft process contains 95-98% of the total chemicals removed during cooking of the liquor.

Answer 14

True

Question 15

Uses either Na2CO3 or Na2SO4 in cooking liquor.

Answer 15

Soda Process

Question 16

It worked well only with deciduous (hard) wood.

Answer 16

Soda Process

Question 17

Similar to Kraft Process but uses different chemicals in cooking liquor.

Answer 17

Sulfite Process

Question 18

Sulfurous acid (H2SO3) is used instead of caustic (NaOH) solutions

Answer 18

Sulfite Process

Question 19

Most common raw materials in sulfite process

Answer 19

Spruce

Question 20

Primary waste product in sulfite process

Answer 20

Waste sulfite liquor

Question 21

Process Flow of Kraft Process

Answer 21

Woodyard Section > Pulp Processing Section > Bleaching Section > Paper Processing Section > Liquor Recovery Section

Question 22

In the pulp processing section, Na2SO4 is added to the white liquor, which was composed of Ca(OH)2 and NaOH created through _____________ .

Answer 22

Causticization

Question 23

Resulting liquor in pulp processing section

Answer 23

Black liquor

Question 24

Used for pre-bleaching

Answer 24

Chlorine gas (Cl2)

Question 25

It reduces Kappa Number

Answer 25

Sodium hydroxide (NaOH) treatment

Question 26

dimensionless number that measures the lignin content of pulp

Answer 26

Kappa Number

Question 27

Kappa number for paper

Answer 27

K < 5.00

Question 28

Main chemical used in bleaching

Answer 28

Chlorine dioxide (ClO2)

Question 29

Used in pulp refining in the paper processing section.

Answer 29

Jordan Machine

Question 30

It delivers a uniform pulp slurry on the conveyor wires.

Answer 30

Headbox

Question 31

large amounts of dewatering

Answer 31

Rolling press

Question 32

Effectively remove moisture left after pressing

Answer 32

Dryers

Question 33

a dilute, white stock solution of hot water and fibers.

Answer 33

White water

Question 34

Four main sections of Fourdrinier Machine (4)

Answer 34

1. Wet end section 2. Wet press section 3. Dryer section 4. Calendar/Ironing section

Question 35

Black liquor is removed from washing of the pulp.

Answer 35

Liquor recovery section

Question 36

This is produced in the liquor recovery section to be added with Na2SO4 for cooking chipped wood.

Answer 36

White cooking liquor

Question 37

Two principal types of reaction in the sulfite process (2)

Answer 37

1. Sulfonation and solubilization of lignin by the bisulfite ion 2. Hydrolytic splitting of the cellulose-lignin complex

Question 38

The ______ from the Kraft Process can also be used as a cooking medium in neutral sulfite process.

Answer 38

Green liquor

Question 39

Type of semi-chemical pulping (1)

Answer 39

1. Neutral Sulfite Process

Question 40

Pulp yields are usually at 65-80% compared to 50-55% for chemical pulping.

Answer 40

Semi-chemical pulping (Neutral sulfite)

Question 41

Absence of chemical treatment

Answer 41

mechanical pulping

Question 42

Uses HPHT to soften the lignin and make mechanical pulping more efficient.

Answer 42

Thermomechanical pulping

Question 43

Other Pulping Processes (4)

Answer 43

1. Solvent Pulping 2. Secondary Fiber Pulping 3. Rag Pulping 4. Dissolving Pulping

Question 44

other term for secondary fiber pulping

Answer 44

Recycled Fiber Pulping

Question 45

Used cotton as raw material

Answer 45

Rag pulping

Question 46

Post-treatment of high-quality sulfite pulp with NaOH

Answer 46

Dissolving Pulp

Question 47

Two Main Types of Paper manufacturing

Answer 47

1. Wet Processes 2. Dry Processes

Question 48

Two general processes of wet process

Answer 48

1. Beating 2. Refining

Question 49

Equipment used to beat plant fiber to make the paper stronger and more uniform.

Answer 49

Hollander Beater

Question 50

Used in pulp refining, deforming, defibering, and dispersing without cutting.

Answer 50

Jordan Engine (Conical Refiner)

Question 51

Other machine used in wet process.

Answer 51

Fourdrinier Machine

Question 52

Used because wet process is expensive and has complex equipment

Answer 52

Dry Process

Question 53

Also called as specialty papers

Answer 53

Coated papers

Question 54

Coating with a substance to produce specialty papers.

Answer 54

Sizing