Upload
kieran-smalls
View
214
Download
0
Tags:
Embed Size (px)
Citation preview
Pulp and Paper Makingin South Africa
Raw Materials Derived from Renewable Resources
Pulping Processes
bull Chemical Pulping
bull Mechanical Pulping
bull Chemo-Mechanical or Semi Chemical
bull Waste Repulping
Mechanical action breaks the ML which is morebrittle than the fibre wallbull The fibre wall is left intact but substantial fibre cutting occursbull Chemical composition is not altered very much
Mechanical Pulping
Mechanical Pulping
Wood physically taken apart ndash recovery highbull Dense species not usually used due to short thick walled fibres and high of vesselsbullResinous species can also present problems
bullYield - high but pulp unsuitable for many uses due to lignin content which stiffens fibresbull Lignin also results in yellowing of pulp with time
Mechanical Pulping ndash SWGPulp produced by pressing logsagainst rotating grindstone1048766 Fibres are compressed andloosened1048766 Friction creates heat to soften the lignin
Mechanical Pulping -SWG
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Raw Materials Derived from Renewable Resources
Pulping Processes
bull Chemical Pulping
bull Mechanical Pulping
bull Chemo-Mechanical or Semi Chemical
bull Waste Repulping
Mechanical action breaks the ML which is morebrittle than the fibre wallbull The fibre wall is left intact but substantial fibre cutting occursbull Chemical composition is not altered very much
Mechanical Pulping
Mechanical Pulping
Wood physically taken apart ndash recovery highbull Dense species not usually used due to short thick walled fibres and high of vesselsbullResinous species can also present problems
bullYield - high but pulp unsuitable for many uses due to lignin content which stiffens fibresbull Lignin also results in yellowing of pulp with time
Mechanical Pulping ndash SWGPulp produced by pressing logsagainst rotating grindstone1048766 Fibres are compressed andloosened1048766 Friction creates heat to soften the lignin
Mechanical Pulping -SWG
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Pulping Processes
bull Chemical Pulping
bull Mechanical Pulping
bull Chemo-Mechanical or Semi Chemical
bull Waste Repulping
Mechanical action breaks the ML which is morebrittle than the fibre wallbull The fibre wall is left intact but substantial fibre cutting occursbull Chemical composition is not altered very much
Mechanical Pulping
Mechanical Pulping
Wood physically taken apart ndash recovery highbull Dense species not usually used due to short thick walled fibres and high of vesselsbullResinous species can also present problems
bullYield - high but pulp unsuitable for many uses due to lignin content which stiffens fibresbull Lignin also results in yellowing of pulp with time
Mechanical Pulping ndash SWGPulp produced by pressing logsagainst rotating grindstone1048766 Fibres are compressed andloosened1048766 Friction creates heat to soften the lignin
Mechanical Pulping -SWG
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Mechanical action breaks the ML which is morebrittle than the fibre wallbull The fibre wall is left intact but substantial fibre cutting occursbull Chemical composition is not altered very much
Mechanical Pulping
Mechanical Pulping
Wood physically taken apart ndash recovery highbull Dense species not usually used due to short thick walled fibres and high of vesselsbullResinous species can also present problems
bullYield - high but pulp unsuitable for many uses due to lignin content which stiffens fibresbull Lignin also results in yellowing of pulp with time
Mechanical Pulping ndash SWGPulp produced by pressing logsagainst rotating grindstone1048766 Fibres are compressed andloosened1048766 Friction creates heat to soften the lignin
Mechanical Pulping -SWG
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Mechanical Pulping
Wood physically taken apart ndash recovery highbull Dense species not usually used due to short thick walled fibres and high of vesselsbullResinous species can also present problems
bullYield - high but pulp unsuitable for many uses due to lignin content which stiffens fibresbull Lignin also results in yellowing of pulp with time
Mechanical Pulping ndash SWGPulp produced by pressing logsagainst rotating grindstone1048766 Fibres are compressed andloosened1048766 Friction creates heat to soften the lignin
Mechanical Pulping -SWG
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Mechanical Pulping ndash SWGPulp produced by pressing logsagainst rotating grindstone1048766 Fibres are compressed andloosened1048766 Friction creates heat to soften the lignin
Mechanical Pulping -SWG
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Wood chips are broken down into fibres by bars ontwo rotating or one rotating and one stationary discs
Mechanical Pulping -Refiner Mechanical Pulp (RMP)
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
To decrease energy cost or to improve pulp quality chemical treatments (alkaline sulphite sodium sulphite) are often added to mechanical pulping1048766Pretreatment of chips (to lower energy)1048766Inter-stage treatment (lower energy increase fibre flexiblity)1048766Post-treatment (fibre flexiblity)
Chemi-thermomechanicalPulps (CTMP)
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Chemical Pulping
Chemicals degrade amp dissolve the lignin1048766 Hemicellulose also removed1048766 Mainly secondary wall material remains
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Chemical Pulping
bull Soda
bull Soda Anthra Quinone
bull Kraft = Caustic Soda + Sodium Sulphide (High strength efficient recovery of chemicals handles a variety of species tolerates bark)
bull Neutral Sulphite Semi Chemical = Sodium Carbonate + Sodium Sulphite
bull Sulphite ndash H2SO3 + bisulfite bright pulp amp easy to bleach higher yield easier to refine
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Kraft Recovery Cycle
bull Black Liquor is Concentrated in Multiple Effect Evaporators to about 65 ndash 70 Solids
bull This Heavy Black Liquor is fired in a Soda Recovery Furnace
bull The Smelt is dissolved in water to form Green Liquor ndash Sodium Carbonate and Sodium Suphide
bull Green Liquor is causticised with un-slaked lime filtered and polished to form white liquor
bull The Calcium Carbonate sludge is burnt in Kilns
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Soda Recovery
bull Soda or SodaAQ Liquor is concentrated to 55-60 Solids in Multiple Effect Evaporators
bull Strong Liquor is sprayed to form droplets in a Fluidized Bed Reactor
bull Further evaporation takes place as droplets fall
bull Organics burn in the fluidized bed
bull Inorganics recovered in the form of Sodium Carbonate
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Washing
1048766 Aim is to
bull minimize black liquor carryover
bull recover dissolved solids
1048766 Solution contains
bull Lignin (30-45 )
bull Hemicellulose (28-36 )
bull Extractives (2-5 )
bull Na2O (25-40 )
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Beating andRefining
1048766 Purpose
1048766 To flatten fibres to ensure maximum surface area for hydrogen bonding in paper
1048766 Beating also unravels fibres
1048766 Beating is done in refiners
1048766 Fluted plug rotates inside
similar shaped housing with ribs
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Beating andRefiningFreeness
1048766 Freeness is term used to
describe pulp potential
1048766 Measured by rate of water passing through set amount of fibre formed on wire mesh
1048766 Well beaten fibre does not allow water to
pass so Freeness is low
1048766 Burst and tensile strength increased by
beating time ndash increases inter-fibre bonding
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Chemical vs Mechanical Pulping
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Chemical vs Mechanical Pulping
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Bleaching ProcessesConventional
bull Chlorination ndash Elemental Chlorine (aromatic substitution of H and addition reactions over the C=C)
bull Alkali Extraction ndash Sodium Hydroxide
bull Chlorine Dioxide or Sodium Hypochlorite
bull Alkali Extraction
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Bleaching ProcessesModern Trends
bull Sulpher Dioxide
bull Oxygen (radical mechanism) or Ozone (addition over the C=C)
bull Chlorine Dioxide
bull Alkali Extraction
bull Chlorine Dioxide
bull Hydrogen Peroxide
bull Exotics
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Paper Making Chemicals
bull Cellulose Fibers ndash the bulk
bull Fillers ndash Clay Calcium Carbonate ndash 0 to 25
bull Strength Additives ndash Starch CMC ndash 0 to 10
bull Sizing Agents ndash Rosin + Alum AKD ASA
bull Wet Strength Additives ndash 0 to 2
bull Dyes
bull Retention Agents
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Major Grades of Paper
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
South African Pulp and paper Industry
bull Number of Paper amp Board Mills ndash 17
bull Number of Pulp Mills ndash 9
bull Paper amp Board Capacity = 2421 Mt ndash Local Consumption = 75
bull Pulp Capacity = 2472 Mt ndash Local consumption = 60
bull The Industry is a very important foreign exchange earner
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Per Capita Paper Consumption kg
0
50
100
150
200
250
300
350
USA Europe RSA WORLD AFRICA
1993199920022004
Pulp and Paper Makingin South Africa
Pulp and Paper Makingin South Africa