By-products from pulping of wood

and non-wood raw materials

Important source of biomass chemicals

FIBRA seminar, March 23rd, 2015

Klaus Niemelä

VTT Technical Research Centre of Finland

2 28/5/2012

Examples of early (chemical) wood industries

Naval strores production (turpentine, resin)

Thermal processes

Tar production & by-products

Wood distillation industry (methanol, acetic acid etc)

Charcoal manufacture (important e.g. in Sweden for steel

industry in the 19th century – impacts on pulping byproducts)

Oxalic acid manufacture by alkali

fusion of sawdust in the past

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(Hard)wood distillation industry

The first industrial large-scale wood biorefinery process

Main operation period c. 1840-1920s/1930s

New plants constructed still in the 1950s/1960s, even later

The only industrial source for methanol and acetone until

1910s/1920s

Main source for acetic acid

Many other products also isolated

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Pulp mill biorefineries: pulp, chemicals, biofuels

Pulping process

Harvesting residues

AgromaterialsRecovered paper

Process(es)

Integratedpower/energyproduction

Processstreams

Pulp, paper

Energy

Biofuels

Chemicals

Chips

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Current share of pulping methods (for 190-200 Mt pulp)

440 40

very many

40

Number of pulp mills

(10 pre-

hydrolysis

mills)

No organosolv processes

industrially operating

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Alkaline (kraft and soda) pulping:

Composition of material dissolved into spent liquors

(>130 million tons annually)

7

Distribution of black liquor organics

Softwood Hardwood

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Industrial by-products from alkaline pulping processes

(kraft and soda)

Currently

Turpentine (chemicals, parfymes, vitamins, polymers…)

Tall (pine) oil for fatty acids, resin acids, phytosterols

Lignin

In the past (only)

Methanol, ammonia

Heat treatment products (acetone, 2-butanone, oils…)

Dimethyl sulphide, dimethyl sulphoxide, dimethyl sulphone

From the prehydrolysis/extraction-kraft processes (past)

Xylose, furfural, hexoses, ethanol, yeasts…

Polysaccharides

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Current turpentine production (thousand tons)

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Turpentine composition

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Methanol

Found in pyroligneous acid (wood distillation) in 1812

Produced in the late 1800s and early 1900s only by dry

distillation of (hard)wood

Discovered from kraft pulping streams 1908

In 1912, 5 Swedish mills recovered methanol!

The production peak in Sweden was in the 1930s (500 t/a)

Isolated at 3 Finnish mills in 1912-1924

No information found on production outside Scandinavia

Nowadays crude methanol produced from foul condensate

stripper off-gases (mainly for combustion)

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First mill-scale purification system recently started at

Al-Pac, Canada, based on 2-step distillation

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Ammonia as a by-product

Isolation integrated into the separation of turpentine and methanol

The method was developed by Alfons Hellström (1877-1965)

Applied only at Kotka mill, Finland (in the 1910s)

The production peak was in 1917, 8 tons of ammonium sulfate

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Erik Ludvig Rinman

1874-1937

Pulp mill biorefinery pioneer

(started in Sweden),

whose efforts accelerated

a lot of studies that still

go on…

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Heat treatment of black liquor, discovered by Rinman to increase

the formation of useful volatile compounds (kg/t pulp)

Promising early yields were approximately:

Methanol 30 kg

Acetone 20 kg

2-Butanone 20 kg

Light oils 18 kg

Heavy oils 50 kg

Industrial-scale process – Rinman method – operated at a German

pine soda pulp mill 1922-1929. Was not economically a big success,

for technical reasons and for discovery of methanol synthesis.

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Production at Regensburg, 1927-1929

Methanol 110 t

Acetone 49 t

2-Butanone 47 t

Light oil 56 t

Heavy oil 198 t

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The Rinman process had a huge impact on studies

on pulping spent liquor utilisation

Acids

Phenols

Ketones, etc

Heat treatments

Oxidations

Gasifications, etc

Still going strong for the

same products

18 28/5/2012

DMSO – Dimethyl sulphoxide (via DMS)

More valuable product from black liquor processing

Pilot-scale production in Finland from

black liquor in the 1940s

Knowledge transferred to the USA,

wher production from the 1960s to

2010. During the recent years, c. 1/3

of global DMSO was from black liquor

Also produced in the Soviet Union

(1974-1990s)

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Tall oil (pine oil)

Isolated at numerous softwood kraft pulp mills worldwide

Distilled at >20 distilleries to different fatty and resin acid fractions

(and residues)

Phytosterols also isolated in many countries

Production figure steady: 1,4-1,5 million tonnes

The main fractions are valuable products

Recent interest also for the manufacture of biodiesel

Softwood (tall oil and gum rosin) are the only sources of pine rosin

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Alternative source for resin acids: gum rosin

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Rosin use in Europe

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Tall oil fatty acid use in Europe

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Tall oil (TO) phytosterol manufacturers

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Kraft (sulphate) lignins

Annual "production" over 60 million tons.

Used as a chemical/material: under 150,000 tons.

Dominating company: MeadWestwaco, USA

New and planned isolation capacity in the US, Canada, Finland…

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Kraft lignin (potential) uses

Phenolic resins

Panelboard adhesives

Thermoset resins for moulded products

Friction materials

Adsorbent materials

Foundry resins

Insulation materials

Decorative laminates

Rubber processing

Antioxidant applications

Printed circuit board resins

Animal health applications

Composites and biocomposites

Carbon fibres (for vehicles and other uses)

Synthetic lignosulphonates, with a large number of well-established uses

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Lignin recovery for non-wood soda pulping

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Pre-extraction/hydrolysis before pulping

• Aim to recover a substantial part of hemicelluloses (xylan,

glucomannan) as polymers or monomers

• Pulp properties should not be affected

• A lot of interest in Europe and North America

• Sugars to be fermented to ethanol, or succinic acid (150,000 tons

of ethanol expected in 400,000-ton softwood pulp mill), or other

chemicals

• Method applied in the 1970s to isolate arabinogalactan before

pulping of larch wood chips (St. Regis company, products known

as Stractan)

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Prehydrolysis-kraft pulping for the prouction of dissolving pulp

From the prehydrolysate, isolated or produced at several mills in

the 1960s-1990s (water prehydrolysis)

Furfural

Xylose

Ethanol

Fodder yeast (e.g. 20,000 t/a

at Bratsk, USSR)

Today water vapor

hydrolysis used

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Bratsk prehydrolysis plants in the 1970s (USSR)

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Dissolved products from acidic sulphite pulping

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Lignosulphonates - production

Annual "production" over 4-5 million tons.

Used as a chemical/material: 1.8 million tons.

Production in Europe, Asia, North and South America, Africa.

Several companies operating, LignoTech dominating.

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Lignosulphonate functionality & substitutes

Source: Borregaard

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Vanillin from lignosulphonates

Today, 15% of global vanillin production is based on oxidation of

lignosulphonates

Two producers: Borregaard (Norway), Bailu Papers (China)

In the past, also produced in the US, Canada, Japan, USSR, Poland.

Many plants closed 1980-2000.

Isolated by-products include dehydrodivanillin, acetovanillone, and

calcum oxalate

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Carbohydrate-based products from sulphite spent liquors

Xylose, arabinose

Galactose, mannose, rhamnose

Fermentation products ethanol, torula yeast, pekilo protein,

ribonucleic acids

Some fermentations also use aldonic and uronic acids, and acetic

acid

Furfural

Acetic acid

The isolation of lignosulphonates and carbohydrate products offer

interesting full biorefinery concepts

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Isolation of acetic acid at Lenzing, Austria

Food-grade product

Furfural isolated at the

same time

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Ethanol from wood (sulphite pulping)

From: G. Rødsrud (2011)

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Ethanol from wood (sulphite pulping)

From: G. Rødsrud (2011)

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Past sulphite ethanol plants in Finland

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Current ethanol producers

From: G. Rødsrud (2011)

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Case from Finland, 1980s

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Lenzing biorefinery, Austria

The net calorific value corresponds to

abt. 220 kg fuel oil per t of pulp produced!

Dissolving

pulp

Acetic acid

Spent liquor Excess

energy

Beech wood

50%

Pulp

mill

39% Furfural

Xylose

11%

Source: H. Harms, FTP Conf. 2005

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Borregaard, Norway

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Torula yeast and pekilo protein

Pekilo protein produced only at two plants in Finland (1970s-1980s)

Torula yeast currently produced at a few countries

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Ribonucleic acids by Nippon Paper

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Semichemical pulp mills

High-yield pulp mills (hardwood) for corrugated board, NSSC

process originally developed in the US in the 1920s to pulp wood

from tannin extraction

Pioneering acetic and formic acid separation processes developed

in the USA and Finland

Extraction columns

for acetic acid

Sonoco 1958-1970s

Savon Sellu 1979-1991

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Chestnut extraction-pulping process

operated in Italy 1957-2009

NSSC

pulping

Hot water

extraction

Tannin

Chips Pulp

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Mechanical pulping processes

Due to the high pulp yield (85-98%), limited opportunities for by-

products exist

Sulfur-free TMP turpentine isolated at a few mills (US, Canada,

Sweden, Finland…)

Opportunities to isolate and utilise of galactoglucomannan from

CTMP process waters thoroughly studied (not in mill-scale)

50 28/5/2012

VTT - 70 years of

technology for business

and society

Final slide is optional in VTT’s internal presentations