Though the conventional scouring process is extremely using now-a-days, it has great bad effect on environment.
Many of the developed countries are avoiding the conventional scouring process replacing enzymatic,ecofriendly, scouring processes.
Bioscouring is an eco-friendly scouring process it has great future.
The new enzymatic procedure is corresponding with a significant role in minimizing the de-mand of energy, water, chemicals, time and costs.
2. Scouring
• Scouring is an important pre-treatment operation in the
processing of cotton and cotton blended materials.
• The main objective of scouring is to remove the non-cellulosic
constituents of cotton fiber which make the fiber non-
absorbent.
• Conventionally, scouring is done in a hot aqueous solution of
NaOH to remove hydrophobic components from the primary
wall (e.g. pectin, protein and organic acids) and the cuticle
(waxes and fats).
3. Conventional method
Conventional method:
Alkali scouring.
Where 3-4% caustic soda is used at high temperature (90-95oC)
for long duration (2-3hours)
Disadvantages of alkali scouring:
1) Damage to fiber.
2) Requirement of large quantity of water for washing.
3) Heavy effluent load (Salts of neutralization)
4. Enzymatic Scouring
Enzymatic Scouring or Bio-Scouring
can simply be defined as the application of living
organisms and their components to remove the
natural and added impurities.
Bioscouring is a process by which alkaline stable
pectinase is used to remove pectin and waxes
selectively from the cotton fiber
5. Enzymes used for Bio scouring
• Pectinase – (Pectins removal)
• Protease – (Removal of proteins)
• Lipases-(removal of fat )
• Combination of 2 or 3 enzymes
6. Enzymes used for Bio scouring
• Pectinase:- Pectinases are used for the
removal pectic substances from cotton.
• Lipases :- They are used for the removal of
natural fatty substances from cotton
• proteases:- proteases are enzymes that
catalyze the hydrolysis of proteins
7. Recipe
Enzymatic scouring was carried out by the following
recipe-
Enzyme : .............................................3 g/L or 0.5%
Sequestering agent : ...........................1 g/L
Wetting agent : ...................................2 g/L
Emulsifier ………………………………………. 0.5-1.5 g/l
Temperature : .....................................50-60oC
Time : ................................................30 min
M: L : ................................................1:10
PH : ...................................................7-9
11. Parameter Bio Scouring Alkaline Scouring
pH 7-8 12-13
Temperature 50-600C 950C
Residual Pectin 20-25% 10-11%
Weight loss <1.5% 4-6%
Handle Very soft Harsh and papery
Rinse Water
Consumption
30-40% of Alkaline scouring
TDS 50% of Alkaline Scouring
BOD 50% of Alkaline Scouring
COD 50% of Alkaline Scouring
14. Advantages
1. (BOD) and (COD) of enzymatic scouring process are 50 % as
compared to alkaline scouring (100 %).
2. Total Dissolved Solid (TDS) of enzymatic scouring process is
50% as compared to alkaline scouring (100%).
3. Handle is very soft in enzymatic scouring.
4. It also minimizes health risks of operators .
they are not exposed to hazardous chemicals.
15. Advantages
• Save energy
• Save cost
• Water saving
• Temperature saving
• Time saving
• Smoother surface profile(Fully retain cellulose structure)
• Lesser weight loss
• Lesser costs of auxiliaries
• Mild application condition
• Environmental benefits
• Reduces effluent treatment process/ ETP cost
16. Disadvantages
• partial removing of cotton fiber waxes.
• Enzyme activity can, however, be reduced or even completely
destroyed (denatured) by high temperatures, extremes of pH
and high concentrations of electrolytes that destroy their three-
dimensional structures. Heavy metal ions and oxidizing and
reducing agents also deactivate the enzymes.
• The degree of whiteness is often less and the process is not
suitable for removing seed-coat fragments and mote
adequately.
17. Summary
Though the conventional scouring process is extremely using
now-a-days, it has great bad effect on environment.
Many of the developed countries are avoiding the conventional
scouring process replacing enzymatic,ecofriendly, scouring
processes.
Bioscouring is an eco-friendly scouring process it has great
future.
The new enzymatic procedure is corresponding with a
significant role in minimising the de-mand of energy, water,
chemicals, time and costs.
18. References
• Institute of Technology Textile, Garment and Fashion Design,
Bahir Dar University .
• Seminar on Bio-Scouring process,
Karachi institute of Textile Technology.
• Prof. (Dr.) M.D.TELI
Bahir Dar University .