enzyme applications in pulp and paper_2

7/31/2019 Enzyme Applications in Pulp and Paper_2

1/33

Enzyme Applications in Pulp and Paper:An Introduction to Applications

Dr. Richard Venditti

Associate Professor - Director of Graduate ProgramsDepartment of Wood and Paper ScienceBiltmore Hall Room 1204

Raleigh NC 27695-8005- -. .

Email: [email protected]

Endo-Beta 1,4 XylanaseSlides courtesy of Phil Hoekstra.


2/33

reactions

perform needed functions e start ng mo ecu es t at enzymes

process are called substrates and

t ese are converte to pro ucts

Endo-Beta 1,4 Xylanase


3/33


4/33

substrates Activit affected b inhibitors H

temperature, concentration of substrate

Commercial enz me roducts are t icallmixtures of different enzymes, theenzymes often complement the activity of

one anot er



5/33

Types of Enzymes in Pulp andaper an espect ve u strates

---

Cellulase --- cellulose fibers

rotease --- prote ns

Hemicellulases(Xylanase) ---hemicellulose Lipase --- glycerol backbone, pitch

--- , Pectinase --- pectins



6/33

Enzyme Applicationsn u p an aper

Treat starches for a er a lications

Enhanced bleaching Treatment for pitch n ance e n ng

Treatment for stickies in paper recycling Reduce refining energy Cleans white water s stems Improve softness in tissue Clean outs



7/33

Starch Conversion for Surfaceoat ngs

Amylases are used to cleave starchmolecules to reduce the viscosit

Used for surface sizing and for starch in

Not used for dry strength agent additive



8/33

cleave hemicelluloses in fiber, making the

May be able to reduce bleaching

Can improve brightness



9/33

processes

-

are more stable in water, wont deposit as



10/33

CH2--------- CH ---------CH2 Triglycerides

Ester-Bonds

O OO

=

(CH2)15 CH3

==

(CH2)15 CH3 (CH2)15 CH3

glycerol

OH

CH2--------- CH ---------CH2

C=O

OH OH


(CH2)15 CH3


11/33

at the surface of the fibers, stuck to microfibrils Cellulase and hemicellulase enz mes h drol ze

these microfibrils, releasing the adhesives

Enz me assisted DI re orted to remove 30-60%more toners

Enzyme assisted DI reported to improve

brightness by 4-5 points



12/33

polymers used in toners and adhesives

Less deposits, less clean up on PM Can be used as substitute for talc or

solvent based dispersants



13/33

- (CH2 CH - CH2 CH - CH2 CH )n -

PVAcEster-Bonds

O OO

=

CH3

==

CH3 CH3

PVAlcohol

- (CH2 CH )- CH2 CH - CH2 CH )n -

OH

C=O

OH OH


CH3


14/33

polyvinyl acetate

- - - -

Hydrophobic

Surface

OCOCH3

A lomerates of PVAc

with Esterase

polyvinyl alcohol+acetic acid

OH

OH

HO

OH

OH

OH

OH

OH

HO

OH

OH

OH

HO

-(-CH2CH-)n-

OH+ CH3COOH

Pol vin l alcohol

OH

OH

HO

OH

OH

OH

OH

OH

OH

OH

HO

OH

OH

OHHO

OH

OH

OH

HOOH

OH

HOOH

OH

OH

OH

OH

OH

OH

OHOH

OHOH

OH

OH


OH

OH

OHOH

Hydrophilic

OH OH


15/33



16/33

stickies transfer on reel samples

during Optimyze Plus 735 evaluation

120

140

0.8

1

.

(lb

/t)

count

PPM

BLX dosage

60

80

stickies

0.4

0.6

13064

dosag

0

20

40

0

0.2BL


2/12 3/4 3/24 4/13 5/3 5/23


17/33

Caustic replacement:

neutra e n ng or newspr nt e n ng

to swell fibers, improving paper makingotential

Cellulase enzymes can be used in

con unction with or as a substitute for thecaustic to swell fibers

Neutral deinking has some advantages

including less COD in the white water,lower costs



18/33

depolymerization of cellulose and swellingof fibers, more flexible fibers

Reduction of fines

decrease energy consumption or obtainimproved strength at higher freeness

Often better runnability or less dryerenergy required



19/33

Fibrillation

Endo-Beta 1,4 Xylanase4/29/2009


20/33

-

process

Reduces refining energy Changes the refining curve

Old rules do not a l

Laboratory Testing



21/33

MILL: Quebec

FIBER: Recycled/Softwood Kraft GRADE: Napkin

GOAL: Increase tensile strength to

middle of specification, reduce

METHODS: Treated MOW stock at the pulperwith 0.5 to 1.0 kg/tonne BZM 2545,

about 3 hours of contact time



22/33

Machine Trial of Buzyme 2545

n ap n gra e40

45

270

275

25

30

35

e(%)

265

ngth

15

20

KraftUsag

255

260

TensileStr SWK Usage

Tensile

5

10

250

0

Pre-trial Trial

245



23/33

Machine Trial of Buzyme 2545

n ap n gra e25

250

300

15

20

(%)

200

gth

10KraftUsage

100

150

TensileStre

SWK Usage

Tensile

550

0

Pre-trial Trial0


Refining energy reduced


24/33

Results: Machine Trial of Buzyme 2545

in Napkin grade

Increased tensile to a comfortable range

e n ng energy re uce

Drainage is better, but cannot takeadvantage of it, due to drive limitations



25/33

cause drainage, formation and paper

Cellulase enzymes hydrolyze these fines,,

Can run PM faster (up to 10% faster in

some cases



26/33

hydrolyzing cellulose in fibers, creating,

Softness increases of up to 25%

as severa patents, some onateto NCSU



27/33

MILL: Quebec FIBER: 95% SWD/5% Recycled Fiber

GRADE: Premium Bath

GOAL: Reduce refining energy, increase,tensile

METHODS: Treated stock at the pulper with

0.5 to 1.0 kg/tonne BZM 2545,about 3 hours of contact time



28/33

Bulk vs. Tensile

Buz me 2535 vs. Gl ox lated Pol acr lamide

11

10

Average Bulk to Tensile

Increase of 3.5%

9

B/BW

8

7

12 14 16 18 20 22


Buzyme 2535 Gloxylated PAM

Linear (Buzyme 2535) Linear (Gloxylated PAM)


29/33

Maintained tensile . .

Able to reduce BWT due to increase in tensile

,better drainage



30/33

Reduction in refiner energy

Less fines generation Better drainage

Softer feel

Less dustin Cleaner white water

Fiber substitution


ou use more , ess v rg n


31/33

Improved biodegradability of pulp

m waste water Cellulases and Hemicellulases used

to degrade cellulose and other highmolecular weight polymers

rat o o omest c sewage2:1

water up to 5:1

H drol sis of cellulose fines b

enzymes to lower molecular weightsugars that are more biodegradable



32/33

ups of starch preparation/application

Protease used as biodispersants or- ,

molecules in deposits and solubilize



33/33

Enz mes are reen chemicals that canimprove operations in pulp and paper

Wide variety of enzymes, must be

work

Several widely accepted applications,s arc , eac ng, c ean ups Future: high valued functionalized fibers,

im roved ul in s ecialized a er

properties, conversion of wastes tofermentable sugars.


enzyme applications in pulp and paper_2

Documents