bio scouring

Presented By Md .Shahriar Jinnah Biplob Deputy Manager Marketing Sparkle Colors (Agent of Dystar)

ENZYMATIC SCOURING OR BIO-SCOURING CAN SIMPLY BE DEFINED AS THE APPLICATION OF LIVING ORGANISMS(PECTINASES ENZYME) AND THEIR COMPONENTS TO REMOVE THE NATURAL AND ADDED IMPURITIES

Introducing Bio-Scouring: A Cost Effective and Eco-friendly Process for the Generation Next

In bioscouring process only one bath is used before the actual dyeing starts, whereas in conventional process a minimum of 5 baths are used. This leads to a total 4 bath saving. Considering an MLR of 1:7, the total amount of water that will be saved is about 28 liters for every Kg. processed. For a unit doing a 30 Mt. of bleaching every day, the amount of water that will be saved is 840,000 Liters per day. On annual basis the amounts comes to be 306600,000 liters of water.

Bio-Scouring Method

THE CHEMICAL COMPOSITION OF COTTON IS:Cellulose – 91.00%Water – 7.85%Protoplasm, Pectins – 0.55%Waxes, Fatty Substances – 0.40%Mineral Salts – 0.20%

Mechanism involved in Bio-Scouring

The following two stages mechanisms are involved in bio scouring---Stage 1: Removal of wax ( a major part being fatty acids, alcohols and

esters) is the critical factor for improved wettability. Pectin functions as a ‘glue’ binding wax to the fibre. Pectin removal does not by itself result in wax removal or improved wettability but it renders wax extractable or emulsifiable.

Stage 2: 2/3 or more of the pectin must be dissolved in order to be able to

emulsify enough wax for a good wettability for dyeing.

Bio-Scouring

Flow chart of Bio scouring

Why Bio-Scouring: (Problems of traditional scouring)

It has become an essential demand for the mill managers to sort out an alternative for the traditional caustic scouring process for some of its unavoidable limitations:

Less fibre strength: In traditional scouring process caustic soda works on swelling method and attacks the secondary cell wall being almost pure cellulose which I have discussed earlier and it causes to damage the fibre and its strength as well.

Excessive weight loss: The recommended weight loss for caustic scouring is 3-8%, but in practice it is around 8-12% which means an excessive loss of fabric weight unnecessarily. The factory has to pay extra money for this unavoidable fabric loss which should not be accepted.

Dye loss: Said earlier that caustic works on swelling method by which all the necessary and unnecessary particles are removed from cotton fibre and most importantly it damages the actual structure of cotton fibre which inspire the dye molecules not to fix according to our requirements and it causes a significant amount of dye loss.

Energy and time concern: In caustic scouring it takes around 105°C temperature and to raise the temperature at this degree it requires a huge amount of energy on which sector we are struggling. Not only that to raise and lower this temperature and also for several rinsing it takes more time which reduces the productivity.

Why Bio-Scouring: (Problems of traditional scouring)

Rinsing and neutralisation: In caustic scouring several rinsing steps are practiced which increase the demand of amount of water volume and as this process is carried out at a high pH range (12-14), it needs to neutralise the scouring bath for the processes ahead.

Effluent concern: A lot of harsh chemicals are used in traditional scouring process which are very much responsible to increase the amount of BOD, COD and TDS in the effluent water and increase the unwanted pressure on environment. Caustic scouring is responsible for the lion parts of the total effluent of a factory. It produces -----

54% to the total BOD 49% to the total COD 10-20% of the total pollution load generated during entire textile processing

operation. Risk in chemical handling: The handling of harsh chemicals increase the

possibilities of accident and most importantly the longevity of the workers are badly affected by the handling of this harsh chemicals.

BLEACHING

STANDARD

ECO FRIENDLY

H2O2 30% vol. : 4 g/lNaOH 30% : 2 g/lStabilizer : 0.3- 0.5 g/lDetergent : 0.5 g/lAnticreasing agent : 1.0 g/l

Stabilizer : 0.3- 0.5 g/lDetergent : 0.5 g/lAnticresing : 1.0 g/lBiopolish enzyme : 0.5%Bioscouring Enzyme : 0.5%

H2O2 30% vol. : 15 cc/lNaOH 30% : 3-4 g/l

• Biopolish Enzyme : 0.5%

• H2O2 Killer enzyme 0.2%

Scouring+Bleaching Biopolish

BleachingScouringe+ biopolish

Bio-Scouring Application Process:

Important process parameters: pH and Temperature Wetteners Emulsifiers Pectinase enzyme Water Wetting agent

Buffer Scourzyme L Emulsifier For Bio- Scouring of cotton fabric Scourzyme L of Novozymes is used

as sample which is an alkaline pectinase and it removes pectin and other impurities from the primary cell wall of the cotton fibres without any degradation of cellulose.

Equipment: Any type of dyeing m/c used in textile wet processing.

Recipe and curve for continuous method

Recipe for Bio-Scouring:A typical process for a pad-batch process combining scouring and desizing in one single

step is as follows: impregnation at 60 °C (pH 8 - 9.5) with: 2 - 3 ml/l wetting agent 2 - 5 ml/l emulsifier 5 - 10 ml/l enzymatic compound 4 - 6 ml/l amylase 2 - 3 g/l salt allow to dwell wet for 3 - 12 h, depending on the amount and type of starch hydro extraction and rinsing. Applicability The enzymatic scouring process can be applied to cellulosic fibres and their blends (for

both woven and knitted goods) in continuous and discontinuous processes. When enzymatic desizing is applied, it can be combined with enzymatic scouring. The process can be applied using jet, overflow, winch, pad-batch, pad-steam and pad-roll

equipment.

Advantages of Bio-Scouring over Traditional scouring:

The advantages of bio scouring comparing to traditional scouring can be found in all of the following perspectives----

Quality perspective Economic perspective Environmental perspectiveQuality perspective: It has been described earlier that the main

objectives of scouring are— To get the adequate absorbency for further subsequent processes To get the minimum degree of whiteness for medium to dark shades and

maximum degree of whiteness for light and white shades.

Optimizing the concentration & time of bio scouring using pectinase

Optimizing the temperature & PH of bio scouring using pectinase


TreatmentAbsorbency (time)

Scourzyme L ( 0.4%) 3 sec.



Caustic scouring 1 sec.

The AATCC recommended absorbency standard for drop test is in the range of (1-5) sec. So the absorbency of bio scoured fabric is quite satisfactory.


Degree of whiteness: The whiteness found after bio scouring is quite satisfactory for medium to dark shade but for light and white shade the result is below the satisfaction limit.

Except the above direct qualitative measure of bio scouring, it adds some supplementary quality to the dyed and finished fabric---

Level dyeing Soft feeling No strength loss

Economic perspective: Bio scouring process is very much economical and cost effective comparing to traditional scouring. By considering the following parameters for cost analysis it is found that this process reduces 10-20% of total annual cost which adds a significant amount of profit to the company’s annual turnover.

Less chemical cost Energy saving Time saving Less water consumption Less weight loss of fabric Less dye loss Less effluent treatment cost


Less Effluent

Thanks for watching my presentation

bio scouring

Technology