Bio-scouring:

Bio-scouring with pectinases (enzyme) have shown promise in replacing the traditional alkaline scouring treatment. Some auxiliaries suppliers have introduced an enzymatic process to remove hydrophobic and other non-cellulosic components from cotton. The new bio-scouring process operates at mild pH conditions over a broad temperature range and can be applied using equipment such as jet machines.

It is claimed that, due to a better bleachability of enzyme-scoured textiles, bleaching can be carried out with reduced amounts of bleaching chemicals and auxiliaries. Bio-scouring enzymes actually make the substrate more hydrophilic (which could explain better bleachability), but they are not able to destroy wax and seeds, which are therefore removed in the subsequent bleaching process.

Major Benefits achieved due to enzymatic scouring or bio-scouring:

There is no need for the use of caustic soda in enzymatic scouring. So this process reduced pollution loads, high TDS, BOD and COD in the effluent.

	Enzymatic scouring	Enzymatic scouring + bleaching with reduced concentration of hydrogen peroxide and alkali
Reduction in rinsing water consumption	20 %	50 %
Reduction in BOD-load	20 %	40 %
Reduction in COD-load	20 %	40 %

Tentative 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.

Complete reference Link: http://www3.itv-denkendorf.de/itv2/downloads/d0004918/WG3BucMarek.pdf