preparación de pasta. pulper. funcionamiento

Latin American Operations

Introduccion

• Teoria de operacion

• Variables que afectan el pulpeo.

Pulpeo preparacion de pasta


Funcion del pulper

• Desfibrar

• Mezclar

• Tamizar gruesos

• Controlar la consistencia

del proceso.

• Almacenar pasta.

Latin American Operations Tipos de Pulper

• Baja consistencia (3-6%)

• Alta consistencia (15-20%)

• Pulper de tambor (15-20%)


Pulper de bajo %C tipico

Rotor

Bafles fijos Cuerpo del Pulper

Accionamiento del pulper Plato de extraccion


Pulper de alta consistencia

Rotor

Salida

Cuerpo

Accionamiento Detrasher

o pera


High Density PulperTheory of High Density Pulping

1. Water and waste paper mixed

2. Rotor tears

paper apart

3. Majority of defibering caused by fiber to fiber rubbing

4. Defibering/Rubbing causes ink to breakdown

5. Thicker mix (high consistency) causes more rubbing

6. Target 18% consistency to achieve best results

7. Optimum pulping

time 20-50 minutes


Hi-Con Pulper- Internal View

Pulp circula lentamente debe

girar completamente.

La pulpa se ve

Espesa como concreto.

Son visibles los

contaminantes grandes

El papel se desintegra

En 10 minutos.

El rotor es relativamente grande

Con respecto al cuerpo.


Impactos en calidad

• La consistencia afecta lafriccion fibra a

fibra. La consistencia debe ser tan alta

como sea posible permitiendo la circulacion

en el pulper. 15%-22% C

• Mas tiempo de pulpeo da como resultado

tintas de tamano mas pequeño. Las tintas

pequenas son mas faciles de remover que

las grandes. 20 a 40 minutos

• No se recomienda usualmente la adicion de

quimicos.

Latin American Operations Impactos en calidad

• La temperatura debe ser lo mas baja

posible para permitir que las particulas

de tinta laser se fracturen.

• Bajas Temperaturas mejoraran el

desempeno en la remocion de stickies

en los fine screen.

• La consistencia de descarga debe ser

controlada para permitir que los equipos

posteriores trabajen eficientemente.

Pulper de Tambor Papel reciclado se alimenta

En esta tolva.

Contaminantes

Grandes salen por

este lado al recipiente

de basuras

Los aceptados se lavan

Fuera del tambor por los agujeros

De la superficie del tambor y se

Bombean al tanque de pasta.

Todo el

tambor

rota

Accion de pulpeo - 3 Etapas

Circulacion Impact Defibering

Traer las fibras a la zona

De desfibracion Reducir la pulpa

a masas de fibras Separar las masas

en fibras individuales.

Latin American Operations Pulping Consistency vs. Repulping Time

Pulping Consistency (%)

3 4 5 6 7 8

-40

-30

-20

-10

0

10

20

30

Ch

an

ge

in

Re

pu

lpin

g T

ime

(%

)


Effect of Pulping Consistency

on Defiberization

91

92

93

94

95

96

97

98

99

100

0 5 10 15 20 25 30 35 40 45 50

Pulping Time (min.)

% D

efi

be

riza

tio

n

6% 12% 15%


Effect of Pulping Consistency on Dirt Count (20 minutes pulping)

4395

1580

6961

1403

0

1000

2000

3000

4000

5000

6000

7000

6% 7% 8% 9% 10% 11% 12% 13% 14% 15% 16%

Pulping Consistency

Dir

t C

ou

nt

(pp

m)


Specific Energy

SE = T x kW

B x 60 min

hr

Where: SE

T

kW

B

=

=

=

=

Specific Energy (kW-hr/mton)

Pulping Time (min)

Installed motor capacity (kW)

Pulper capacity (mtons)


Power Input vs. Repulping Time

Change in Power Input (%)

0 25 50 75 100

-60

-50

-40

-30

-20

-10

0

10

Change in R

epulp

ing T

ime (

%)

y = 0,0249x5 - 0,2967x4 - 2,0596x3 + 24,317x2 + 12,237x + 135,6

0

100

200

300

400

500

8.10 8.17 08:20 08:22 08:28 08:34 08:36 08:40 08:51 08:57

Kw

att

Hora

Kwatt pulpeo vs tiempo bache #5


Typical Specific Energy Applied (kW-hr/mTon)

White Ledger

(non wet strength)

Towel (wet strength)

Bleached Kraft Pulp

Bleached Sulfite Pulp

Slush-Maker

90

89-108

54

46

Brute

72

-----

43

36


¿Donde estaría el ahorro aquí?


Aditivos quimicos al pulper

• Blanqueadores (hipoclorito de Sodio)

• Sulfito de sodio /Bisulfito

• Control de slime

• Dispersantes

• Talco

• Ayudantes de pulpeo

• Acidos y causticos

• Colorantes


FINE SCREENING

Proposito:

El objetivo de toda criba fina es eliminar

contaminantes pequenos de la pasta forzada a

travez de su criba (mayores que su ancho de

ranura pero menores que los agujeros de una

criba gruesa) . •Algunas masas de fibra y otros pequenos

contaminantes son tambien removidos.

• Un minimo de tintas seran eliminadas.

•No se espera ganar puntos de blancura.

•Muchos de los contaminantes rechazados son

stickies.


0.050” Hole

1.27 mm

1270 Microns

Fine

Hardwood Fiber

1.15 mm X 30 microns

Softwood Fiber

3.6 mm X 37 microns

INK PARTICLES

100 Microns

50 Microns

10 Microns

2 Microns

0.008”

0.20 mm

slot

200 Microns

Sticky

Particle

Comparison of Particle Size,

Ink Sizes and Screen Openings


Inlet Line

•Contains output

from previous

system.

•Fed between

basket and rotorAccepts Line

•Contains fibers and inks

that mde it through

basket

Rejects Line

•Contains material that

does not make it through

basket (stickies)

Basket

•Slot perforated

barrier between

Accepts and Rejects

•Accepts make it

through the basket

Rotor

•Helps fibers cross through basket

•Helps keeps basket from plugging

Vent Pipe

•Vents entrained air

from screen body

Fine Screen Vetical and Centrifugal

Latin American Operations Fine Screens in Cascade

Primary

Secondary

Next

System

Feed

Prior

SystemFeedAcceptsRejects

Sewer

Tertiary

Arreglo en cascada de tres etapas


Fine screen con arreglo hacia adelante en tres etapas

Fine Screens in Feed Forward

Primary

Secondary

Next

System

Feed

FeedAcceptsRejectsSewer

Tertiary

Primary

Prior

System


Comportamiento del flujo en la superficie de la cesta

Basket

Rotor

•Stock flow ing between

the basket and the rotor

1

Foil

High

Pressure

Vacuum

Accepts

2

•Stock forced through basket

slots due to inlet pressure

•Stock gets extra boost from

centrifugal force created by

rotor foil

+

++

-

- -

3 •Slot velocity is very

important to control

Fine Screen Vetical and Centrifugal


Fine Screen Variables a considerar

Aunque poseen ranuras de poca abertura

se deben tener en cuenta otras variables

en la remocion de contaminantes:

1. Presion de entrada y presion diferencial.

2. Consistencia de entrada,

3.Velocidad de paso por ranura.

4. Rata de rechazo

5. Diseno de la criba, perfil

6. Diseno del rotor y velocidad (intensidad

de pulso).


Velocidad de paso por ranura

100

80

60

40

20

0

SC

RE

EN

ING

EF

FIC

IEN

CY

, %

SLOT VELOCITY, m/s

0.5 1.0 1.5 2.0 2.5 3.0

Compressible

Conformable

Comp./Conformable

Noncompressible

Slotted Basket

0.25 mm (1.010 in)

Slot velocity and Screening Efficiencies

for various types of contaminants


Area abierta de canastilla

• Entre 6% y 9% de O.A.

PL

W

L

DS

W = WIDTH OF SLOT

L = LENGTH OF SLOT

DS = DISTANCE BETWEEN SLOTS

PL = LONGITUDINAL PITCH

% OPEN AREA = W X L X 100

DS X PL

OPEN AREA IN A SLOT PERFORATED BASKET


Influencia de la rata de rechazo

• Entre 25% a 30% en peso en primarios

• Entre 5% a 15% en peso en los trerciarios.

100

80

60

40

22

0 10 20 30 40

REJECT RATE, % OF WEIGHT

EF

FIC

IEN

CY

, %

0.5 mm (0.020 in.) smooth

0.23 mm (0.010 in.) coanda

0.25 mm (0.010 in.) bar

Reject Rates and Screening Efficiencies

for various types of basket styles


Velocidad del rotor - foils

• La velocidad del TIP va generalmente de 16 m/sef a 22 m/seg en criba centrifuga.

22 m/s

13.5 m/s

18 m/s

100

80

60

40

20

0 10 20 30 40

REJECT RATE, % OF WEIGHT

SC

RE

EN

ING

EF

FIC

IEN

CY

, %

Reject Rates and Screening Efficiencies

for various Rotor Speeds


Tipos de rotores

• Su uso depende de la naturaleza de la pasta

a tratar.


Tipos de cribas

• Los disenos modernos se asemejan mas a la tecnologia de C- bar de Voith o Cobra de Kadant, HSW

WAVES LEHMAN

PROFILE TM

Fine Screens Basket Surface Profiles

C-BAR TM

Flow


Sistema fine screen de tres etapas

• Centrifugo Black Clawson – Diabolo Lamort


Principales factores del proceso de flotacion.

•Particulas a remover

• Tamano

• Forma

•Distribucion

•Burbujas de aire

•Numero

•Distribucion de tamano

•Mezclado

•Combinacion de la pasta gris con las burbujas de aire.

•Quimica.


10 m m

100 m m

500 m m

50 m m

Burbuja de aire

1000 m m

Particula de tinta


Quimica

• Surfactante -”agente activo de superficie”

– Contiene cola hidrofobica y cabeza hidrofilica.

– Genera hidrofobicidad a las particulas de tinta y genera espuma.

– Se adiciona en niveles de 0.01% a 0.2%

• Los jabones no se usan porque insolubiliza el calcio que forma depositos y afecta los productos de recubrimiento del secador.


Cabeza Hidrofilica

Cabeza hidrofilica (e.j. oxido de etileno

Cola Hidrofobica

(e.j.oxido de propileno)

Cola hidrofobica

SURFACTANTES DE LAVADO

SURFACTANTE DE FLOTACION

Surfactantes no ionicos.


Factores que afectan el desempeno de la flotacion

• Consistencia de alimentacion: 0.7-1.1%

• Recirculacion: tipicamente de 3-5 pasos (recirculacion redistribuye las burbujas de aire, como estrategia para no incrementar el tiempo de retencion)

• PH: neutro para surfactantes sinteticos.

• Temperatura: Ningun control especial se requiere. Tipica temperatura de proceso 40-45oC

• Contenido de cenizas: ~7% a 10% ayuda.


Consistencia de alimentacion

• Ensayos en KC con – Celda Escher-Wyss CF3C

•1.0% consistencia alimentacion…..71% eficiencia en tamanos de 40 a 165 micron

•1.5% consistencia alimentacion…..43% eficiencia en tamanos de 40 to 165 micron

•1.0% consistencia alimentacion……53% eficiencia en tamanos >160 micron

•1.5% consistencia alimentacion……14% eficiencia en tamanos >160 micron


Weir

Internal

Side Wall

Froth

Knock-Down

Shower

Rejects

Trough

FlotationMain Components

Voith-Sulzer celda “E”

Aceptados : 3-6 pasos. Rechazos van a una 2o

celda en algunos modelos.


Flotation Cell Main Components

RejectsAccepts

Aerated

Pulp

Froth

containing ink

Weir

Rejects

Trough

Interior de la celda “E” de Voith-Sulzer

(With or without

flotation aid)


Feed Inlet

AcceptsRejects

Orifice PlatePulp

Air HolesFlowHelper

Air in

Air-PulpMixture

Celda “E” Voith-Sulzer & Difusor

Algunos modelos

requieren aire

comprimido . Otros

inducen aire

atmosferico.


AIr

Grey stockMixture

of suspension and air

Difusor de aire Escher -Wyss

•Un difusor de aire debe generar burbujas en un rango deseable de

tamano de ~0.3mm.

•Un difusor de aire debe inyectar una cantidad de aire del 30-60% del

flujo de alimentacion.


Celda MAC de Lamort


Celda Mac de Lamort


• Introduction/History

• Refining Theory

• Effect on Sheet Properties

• Refiner Plate Design

• Process Control

Stock Preparation Refining


Hollander Beater


Modern Double Disk Refiner


Jordan Conical Beater (updated version)


Double Disk Refiner with Double Inlet (Duo-Flow Configuration)


Duo-Flo

Sta

tor

Sta

tor

Sta

tor

Sta

tor

Pla

te

Pla

te

Pla

te

Pla

te

Ro

tor



• Refining Theory • Fibers

• Refining Mechanics

• Effect on Sheet

Properties


• Process Control


Latin American Operations Softwood Fiber Cross-Section


Layer Thickness Cellulose Hemicellulose Lignin

microns

Primary 0.03-0.10 10% 20% 70%

S1 0.10-0.20 35% 25% 40%

S2 0.50-0.20 55% 30% 15%

S3 0.07-0.10 55% 30% 15%

M Lamella 1.00-2.00 0% 10% 90%


Moving

Refining Mechanical Action

Stationary

1 Preliminary Dewatering

2 Removal of S1 Wall

3 Wall Extraction, Delamination

4 Fibril Stimulation

5 Dispersion & Hydration

1 2 3 4 5


Fiber

Fibrils

Network

CELLOBIOSE

Lignin

Hemicellulose

Fibril Paper

250

OH

OH OH

OH


Number of Bars Crossings

Net Specific Energy

Refining Intensity

Intensity Factor

Refining Variables


Specific Edge Load Theory (Edge Lengths per Second)

L x L x RPM r s

Lx 60 sec/min ELS =

ELS = Number of edge length crossings per second (m/s)

L r = Total length of bars on a rotor (mm)

L s = Total length of bars on a stator (mm)

Lx = Average length of the bar

RPM =

Rotor speed (revs/min)

Where:

or # bars

rotator X

# bars

stator X

bar

length X RPM


Net Specific Energy

Where: NSE = Net specific energy (kW-hr/mton)

P Tot

= Total refiner power consumed (kW)

P NL

= Refiner no load power consumed (kW)

T = Refiner throughput (mtons/hr)

NSE = P Tot - P NL

T


Refining Intensity

Where: ELS = Total edge lengths per second (mm 2 /sec)

P Tot

= Total refiner power consumed (kW)

P NL

= Refiner no load power consumed (kW)

RI = P Tot

- P NL

ELS



• Refining Theory

• Effect on Sheet

Properties


• Process Control


Latin American Operations Unrefined & Unbleached Kraft Fiber

Latin American Operations Refined & Unbleached Kraft Fibers

Refining Effects

Fiber Shortening

Surface Increase

Crill Production

Lumen Reduction

Axial Compression

Form Change

Structure Change

Unravelling


Strength - Softness Curve Facial Tissue

Invariant Tensile Strength (g/ 3" sheet)

0

2

4

6

8

10

12

0 200 400 600 800 1,000 1,200 1,400

Qa

l S

oft

ne

ss


HI

LO 0 160

Strength vs Refining

KWH/T

Brush

Cut M

ulle

n/T

en

sile


HI

LO

0 160

Bulk vs Refining

KWH/T

Brush

Cut B

ulk

(C

alip

er)


HI

LO 0 160

Density vs Refining

KWH/T

Brush

Cut S

hee

t D

en

sity


GOOD

BAD 0 160

Formation vs Refining

KWH/T

Brush

Cut F

orm

atio

n


HI

LO 0 160

Drying vs Refining

KWH/T

Brush

Cut

Ste

am

Dry

ing



• Refining Theory

• Effect on Sheet

Properties


• Process Control



Bars

Plate

Dams

Refiner Plate Design - Dams

Latin American Operations Refining Action

Refining Action

Plate Clearance

Groove Width

Bar Width

Bar Angle

Incre

asin

g


Hydraulic Capacity of Refiner

Plate Clearance

Groove Width

Bar Width

Bar Angle

Hydraulic Capacity

Incre

asin

g


Coarse Refining

Mild Refining

Cutting

Brushing

Groundwood

High contaminant secondary

Hardwood

Softwood

Clean Secondary

Ni-hard

Ni-hard or Stainless steel

Bar 4.75

Groove - 4.75

Bar - 3.18

Groove - 3.18

7.9

6.4

5

10

1000x10

3000x10

Refiner Plate Design Recommendations

o

o 6

6

Re

fin

ing

Actio

n

Fib

er

Typ

es

Pla

te

Ma

teria

l

Ba

r/G

roo

ve

Wid

th (

mm

)

Gro

ove

De

pth

(m

m)

Ba

r A

ng

le

Cro

ssin

gs

pe

r S

eo

nd

(mm

C/s

)


Brushing Plates Effect of Consistency

Applied Energy (HPD/ADT))

0 1 2 3 4 5 6 7 8 9 10

3400

3800

4200

4600

5000

5400

5800

6200 4.5% Cons.

3.5% Cons.

Bre

akin

g L

en

gth

(m

)


Typical Refiner Curve Burst vs Power

Power Input (kW-hr/mton)

0 20 40 60 80 100

100

120

140

160

180

200

Burs

t (k

Pa)


Recommendations

•Maximize inch crossings per second

• Increase refiner consistency above 4%

•Maintain even pressure through the refinerthrough the use of recirculation

•Monitor differential pressure

• Routinely develop refiner curves



• Refining Theory

• Effect on Sheet

Properties


• Process Control



Electro-Mechancial Actuator


Typical Refiner Controls

FIC

FT

FSL

PSH

M

JIC

Sel. Sw. Target KW (By Operator)

From Chest

JT

I

To Chest

Seal Water

Net Specific Energy Target (By Operator)

NSE Calculation

KT

KIC PSL

Cons. Dilution Water

FINE SCREENING

Purpose:

The objective of all Fine Screens is to eliminate small size contaminants (bigger than its slot width but smaller than the coarse screen’s holes) from the stock. Many of the rejected contaminants are stickies. Few fiber bundles and other small contraries are also removed. Minimal ink removal and no brightness gains are expected.

Latin American Operations OBJETIVO:

Blanqueamiento tiene tres funciones:

• Blanquear las fibras

• Despojar los colorantes.

•Remover lignina en algunos casos.

Todo esto es para mejorar la apariencia de la fibra

reciclada.

Overview:

Una variedad de quimicos se usan para abrillantar o

blanquear la pulpa reciclada. Cada uno tiene sus

ventajas y desventajas. Algunos quimicos son

compuestos oxidantes y otros reductores. Las reacciones

oxidacion – reduccion son las responsables de

decolorizar y deslignificar la pasta.

La lignina es la causa del amarillamiento de la fibra

cuando se expone a la luz o a un alto PH.

Blanqueo


ELEMENTOS DE COLOR EN PAPEL RECICLADO

• Son tres fuentes de color presentes en el papel reciclado.

– Lignina presente en la pasta mecanica.

– Colorantes

– Pigmentos

• Aqui nos ocuparemos de tratar quimicamente las dos primeras.


Agentes quimicos de blanqueo

• Blanqueadores Oxidantes :

– Peroxido de Hidrogeno

– Oxigeno

– Ozono

– Hipoclorito de Sodio

• Blanqueadores Reductivos:

– Acido Formamidina sulfinico (FAS)

– Sodium hydrosulfite


•Most used bleach in waste paper recycling •Bajio, Ecatepec, Ramos Arizpe, Guiacaipuro, Peru,

Owensboro, Aranguren, Malaysia, Philippines,

Thailand, South Africa, PDC, Israel, Argentina, Brazil (3

mills)

•Bleaches by breaking down color

structures attached to lignin

•Best results are seen after washing

•These reactions are irreversible

Hydrogen peroxide


H2O2 + -OH H2O + -OOH

•Perhydroxy anion is responsible for brightening action

•Some dyes and pigments are not sensitive to oxidative

degradation

•Multi valent metal ions and enzymes (Catalase) decompose

peroxide

% Decomposed Peroxide

0 10 20 30 40 50 60 Time (minutes)

20

40

60

80

100

0

Boiled filtrate

Untreated filtrate

Hydrogen peroxide


•High pulp consistency benefits bleaching

•Stabilizers (Sodium silicate) and chelating

agents (DTPA,EDTA) optimize Peroxide

bleaching

0 5 10 15 20 25 30

62

56

58

60

Brightness ISO

% Consistency

60

% Silicate applied

Brightness ISO

1 5 3 4 2

57

58

59

61

62

63 2 % Perox.

1 % Perox.

0.5 % Perox.

Hydrogen peroxide


Cs.

pH

Temp.

Time

Equip.

15-30

9-11

90-130ºC

1-3 hrs pressurized tower

Typical conditions

•Used with Peroxide

•Very little or no brightening on its own

•Color structures are exposed for

peroxide to bleach

•KC South Africa tried to use oxygen

Oxygen


Cs.

pH

Temp.

Time

Equip.

~15

7-8

35-45ºC

~20 min sealed tower

Typical condition in RF

•Very strong oxidizing agent with very

little selectivity

•In RF the target is fluorescence instead of

lignin or colorant

•Very expensive

•Commercial installations have not been

successful

Ozone


Cs.

pH

Temp.

Time

Equip.

15-25

9-11

20-80ºC

20-180 min

tank or tower

Typical conditions

•Used for wood free waste papers because it

generates yellowing over lignin containing

fibers.

•It is cheap to use

•After bleaching Sodium bisulfite can

be used to kill residuals

•Environmentally unfavorable/corrosive

Sodium hypochlorite


Brightness increase 9

7

5

3

0 0 5 7 9

pH value

x

x

x x 25oC

40oC 60oC 80oC

x

•High temperature improves efficiency

•Retention time typically is 30-60 min but some

uses as little as 15min.

•High consistency improves chemical efficiency

but de-gasing is required or entrained air

will consume

hydrosulfite

•Direct coupling of

reductive to oxidative

bleaching is

discouraged

Sodium Hydrosulfite


60

65

70

75

80

85

90Brightness ISO

Yellow Red Green Black 1% Hydro, 70ºC,4%Cs,1 hr

pH 5.5 pH 9.5

•Used for color-stripping of dyes in RF

•Brightens brown fiber in wood containing pulp

(modifies chromophore groups in lignin)

•For color-stripping: pH above neutral

•For lignin bleaching: pH below neutral

•Used by K-C mills:

Bajio, Ramos, Coleshill,

Guaicaipuro, Reisolz

Aranguren, Mainz

South Africa

Sodium Hydrosulfite


Typical RF conditions

•Requires special storage and handling

(self combustible)

•Hydro is less expensive than comparable

reductive bleach FAS

•On site generation is economical and safer if usage is >1

ton/day

•Chemicals used in onsite generation:

comb 1: NaBH4, NaOH, SO2

Comb 2: NaBH4, H2SO4, NaHSO3

(borohydride) (bisulfite) Cs. 4-6 or 10-14%

pH 8-10

Temp. 60-90oc

time 30-60 min

Hydro 0.8-1.6%

Sodium Hydrosulfite

Latin American Operations •Used for color-stripping of dyes

•More efficient than Hydro, particularly on

yellow dyes

•Either high pH (9-11) or high temperature

activates FAS

•High temperatures

improve bleaching

•Used by: Barrow, Hadera

Villanoveta,

Korea,

80

75

70

65

60

Temperature ºC

50 60 70 80

0.2 % FAS

0.4 % FAS

0.6 % FAS 0.8 % FAS

Brightness ISO

FAS

Latin American Operations •Requires a retention time of 40-120 min

•High consistency improves efficiency

but watch out for entrained air.

•Air decomposes FAS although

less susceptible

than Hydro. Brightness ISO 85

80

75

70

65 0 30 60 90 120

Time (minutes)

90oC 70oC 50oC 40oC

0.4 % FAS

0.2 % NaOH

4 % Cs

FAS


Typical conditions

•FAS is more expensive than comparable

reductive bleach Hydro

•Moisture impedes FAS powder make down

Cs. 4-6 or 10-14%

pH 9-11

Temp. 55-90oc

time 30-120 min

FAS 0.4-0.8%

NaOH 1 NaOH : 1 FAS

FAS

Latin American Operations Technology comparison:

Bleach Comparison Table

Oxidative

Bleaches

Peroxide Oxygen Ozone Hypochlorite

Reductive

Bleaches

Hydrosulfite FAS DBI

Bleachables

Lignin and

some dyes

Removes

Lignin aids

bleaching

Most dyes

and

Fluorescence

Most dyes Lignin and

many dyes many dyes many dyes

Disadvantage

s

Poor color

stripper

High capital

cost, high

BOD, poor

color stripper experimental

Darkens

lignin,

environmental

restrictions

Limited

capability:

combustible

More

expensive

than

hydrosulfite

pH 9-11 9-11 7-8 9-11 8-10 8.5-11 7-8

Consistency 15-30 15-30 15-30 15-25 4-6 &10-14 4-6 &10-14 30

Time 1-2 hrs 2-3 hrs 5-45 min 40-180 min 30-60 min 30-120 min <5 min

Temperature 70-90 90-130 23-45 20-80 60-90 55-90 60-90

preparación de pasta. pulper. funcionamiento

Engineering