Eco Friendly Dyeing Final Version

8/2/2019 Eco Friendly Dyeing Final Version

1/33

CopyrightMatex. All Rights Reserved.. EFD SFW071

ECO-FRIENDLY

DYEING


2/33


OUTLINE

Background

Textile Wet Processing

Desizing

Scouring

Bleach Clean Up

Cold Pad Batch Dyeing


3/33


BACKGROUND

Increasing awareness for a cleaner and

greenerliving standards

Enforcement of stricter guidelines and rulingsfrom various associations and Governmentbodies

Challenges faced by Textile Dyeing

companies around the world alike

Matexs belief in being ecologically efficient


4/33


DYEING

PROCESS

DesizingMebyoNHT

ScouringMebyoPT

Bleach

Clean UpMebyoHON

DyeingMegafix B-CPB Soaping

Finishing

Garment


5/33


DESIZING


6/33


DESIZING

Removal of starch used as size duringweaving to prevent unleveled dyeingand poor batch-to-batch reproducibility

Traditional Desizing Methods Acidic: Sulphuric or hydrochloric acid

Oxidative: Persulphate plus alkali or

bromite and alkaliThese treatments reduce the tensile strengthof the fabric.


7/33


DESIZING

Desizing with biocatalyst

Advantages: LESS chemicals involved

ECO-FRIENDLY

EFFICIENT in wide rangetemperature

Specific, NO damage to cellulose

fibres BETTER strength retention

SOFTER fabric feel

SHORTER process time


8/33


DESIZING

Mechanism:

Biocatalyst hydrolyzes -1,4-linkagesin starch

HYDROLYSIS


9/33


DESIZING

Test for degree of desizing

Tegewa Scale

Tegewa Rating: 1 Tegewa Rating: 7


10/33


SCOURING


11/33


SCOURING

Removal of impurities such as

Waxes Hemicelluloses Pectins Mineral salts

from raw cotton during the early stages

of textile wet processing

Prepares fabric for subsequenttreatments Mercerizing Printing

Bleaching Finishing

Dyeing


12/33


SCOURING

AlkalineScouring

Bioscouring

NeutralizationConventional

FabricInput

Washing DyeingNo Neutralization

At low alkalinity (pH 8.5)

In highly alkaline condition

Alternative


13/33


SCOURING

Advantages of bioscouring:

ECO-FRIENDLY (less harshchemical caustic soda)

LESS rinse water needed

REDUCE effluent load REDUCE water consumption

SAVE energy

SAVE cost Fully RETAIN cellulose structure


14/33


SCOURING

Wetting Test

Grey Fabric Treated Fabric


15/33


SCOURING

100%20-45%COD

100%20-45%BOD

100%20-50%Total diss solids (TDS)

100%35-50%Rinse water

consumption

SameSameDye ability

SameSameBleach ability

+ 5 -10% points+ 1-5% pointsBrightness increase

< 1 second< 1 secondWettablility, drop test

4-10%


16/33


140Total water required(tonne)

1:7Liquor ratio

$1.00Fabric cost per kg

(USD)

20Total fabricprocessed / day(tonne)

Basic Assumption

$66,360-Steam cost saving / year2 (USD)

$189.601$410.801Total steam cost / day (USD)

1226Total steam required (tonne)

85.71185.71Steam required / 1 tonne water(kg)

3065Temperature differential (oC)

6095Scouring Temperature (oC)

3030Base temperature (oC)

Energy cost

Bioscouring

AlkalineScouring

Energy Saving

1 Based on steam costUSD$15.80/tonne of steam2 Based on 300 working days peryear3 Based on 4% fabric weight lost4 Based on 1.5% fabric weight lost

Bioscouring

AlkalineScouring

Fabric Saving

$150,0000Weight lost cost saving / year2

(USD)

$300$800Total weight lost cost / day(USD)

30048003Total fabric weight lost / day (kg)


17/33


BLEACH CLEAN UP


18/33


BLEACH CLEAN

UP Removal of H2O2 residual to

ensure leveled dyeing

Bleach Clean Up Alternatives By rinsing only

By reducing agent

With biocatalyst

Bleaching Rinsing DyeingRinsingRinsing Rinsing

RinsingBleaching DyeingRinsingReducing

Agent

RinsingBleaching Biocatalyst

Dyeing


19/33


BLEACH CLEAN

UP Advantages of using biocatalyst:

SAVE water No rinsing required. Can proceed in the same

bath with dyeing process

SAVE energy No more hot rinse, cold rinse, hot rinse

SAVE time As short as 10 min to complete the job!

SAFE H2O2 complete removal without affecting

dyestuff or textile materials


20/33


BLEACH CLEAN

UP Bleach Clean Up with Biocatalyst

- Adjust pH asdesired forsubsequent dyeing

- Add biocatalyst

Bleaching

-Drain-Fill cold

BleachClean Up

Dyeing

- Checkperoxide level

5 10 15 20 25 30 35 40 45 50 55 600

20

40

60

80

100

Time (min)

TemperatureC


21/33


BLEACH CLEAN

UPWater Usage in the Various Bleach Clean Up

Methods

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Water Reductive Biocatalyst

NoofRinseBaths


22/33


Process Time for the Various Bleach Clean Up

Methods

0

20

40

60

80

100

120

140

Water Reductive Biocatalyst

Minutes

Bleaching Rinsing H2O2 Removal


23/33


COLD PAD BATCH


24/33


COLD PAD BATCH

DYEING

A more environmentally sound and

higher quality dyeing method

Process steps:Padding Roll Batching

Washing Soaping Washing

Drying


25/33


COLD PAD BATCH

DYEING Total volume of pad-trough

10 / 15 litres per metre of

width of fabric (example 2metres; volume 20 to 30litres)

Immersion time 1.5sec

Bath temperature 25 30C

Pick up 70 80%

Fabric speed such as thetime to completely renew

the trough should notexceed 10 minutes

Batching time: 8 16hrs

Dyes/AuxiliariesAlkali

4 volumes Batching Vessels1 volume

Mixing Vessel

Foulard with anautomatic level-adjustment


26/33


COLD PAD BATCH

DYEING Advantages of Cold Pad Batch Dyeing:

Simplicity in process of dyestuff application Reduction in water consumption by 50 to

80%

Reduction in energy consumption by up to60%

Reduction in chemical costs, other thandyestuff, by up to 50% due to elimination of

salt and reduction of alkali requirements Reduction in labor costs by 40 to 60%

Minimum fabric abrasion

Excellent shade reproducibility from lot toSource: Cotton Inc 2003/TRI3007


27/33


COLD PAD BATCH

DYEING Reactive dyestuff

A dye type that connect to the fiber through

chemical reactions (covalent bond)

HYDROLIZATION25%

FIXATION75%

R2-DYE-OH R2-DYE-Ocell

HYDROLIZATION

6%

FIXATION

19%

HO-DYE-OH HO-DYE-Ocell

TOTAL6% HYDROLIZATION

94% FIXATION

MONO REACTIVE

DYE-R

HYDROLIZATION25%

FIXATION75%

DYE-OH DYE-Ocell

TOTAL25% HYDROLIZATION

75% FIXATION

BIFUNCTIONAL REACTIVE

R1-DYE-R2


28/33


COLD PAD BATCH

DYEING Megafix B-CPB

Belongs to Bifunctional Reactive DyesGroup

Low to medium substantivity, medium tohigh reactivity

Excellent build-up, high color yield andfixation

Good fastness

Good repeatibility

Good trichromic compatibility

Meet Oeko-Tex 100 requirement

CO C


29/33


COLD PAD BATCH

DYEING Trichromatic

CompatibilityFrom theillustration &data values, itshows that the

trichromaticcolors arecompatible &they give thesimilar shade &tone throughoutfrom the 1stfabric to the 40thfabric.

COLD PAD BATCH


30/33


COLD PAD BATCH

DYEING

1. Based on water & sewer cost of $2.58/1000 gals.2. Based on steam cost $4.38/1000 lbs. of steam. Pad-batch includes extra drying.3. Based on electric power cost of 5.0/kWh.

4. Based on sodium chloride at 4/lb.

Cost Comparison on Reactive Dyeing pre-bleached 100%Cotton ( Greenville, S.C. local currency)

Source: Cotton Inc 2003/TRI3007

77.8%$117.15$33.40$150.55

-Total (ExcludeDyestuff & Labor)

100%$40.0000$40.0041000 lbsSalt

50.0%$1.50$1.503< 30kWh

$3.00360 kWhElectricalConsumption

67.6%$39.77$19.0524,350 lbs$58.82213,430lbs

SteamConsumption

73.6%$35.88$12.8514,980gals

$48.73118,889gals

Waterconsumption

-1 : 1-15 : 1Liquor Ratio

-1000 lbs-1000 lbsBatch size

%

Saving

Total

saving

Pad-batch

cost

Pad-

Batch

Beck

Cost

BeckItem

COLD PAD BATCH


31/33


COLD PAD BATCH

DYEING


32/33



33/33


Eco Friendly Dyeing Final Version

Documents

Transcript of Eco Friendly Dyeing Final Version