reloaded bio

ECO FRIENDLY TEXTILE PROCESSING

Bio scouringPresented by:Fahim Uddin Zauwad 130103006

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).

Conventional methodConventional 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)

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 fibre

Enzymes used for Bio scouring

• Pectinase – (Pectins removal)• Protease – (Removal of proteins)• Lipases-(removal of fat )

• Combination of 2 or 3 enzymes

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

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

Figure: Bioscouring processing curve

1. Water,wetting agent, PH buffer and fabric; 2. Enzyme (pectinase); 3. Emulsifier.

Comparison of Bio-Scouring and Alkali Scouring

Bio-scouring

Blend of Enzymes-Pectinase + Protease

Removes Pectin, protein, Wax, Oil etc

Alkaline-scouring

Sodium Hydroxide

Remove Pectin, Protein, Wax, Oil, Cellulose

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

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.

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

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.

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.

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 .

BIO-SCOURING

Thank you

reloaded bio

Education