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Sustainable Industrial Design and Waste Management
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TABLE 2.23
Recipe for Combined Desize and Scour: Woven Fabric – Misr Beida Dyers
Processing recipe (for 1 ton Combined desize and scour Half bleaching
of fabric)
NaOH (38% Be) (l) 133 75
Espycon 1030 (kg) 4.8 1.5
Egyptol PLM (kg) 2.4 –
Ammonium persulfate 1.2 –
Na 2 SiO 3 (kg) – 16
H 2 O 2 (35%) (kg) – 13.3

• Strong odor of chlorine was noted, resulting from the use of sodium
hypochlorite in the bleaching process.
• Worker safety issues were noticed, associated with the handling of
toxic and hazardous chemicals such as sodium hypochlorite.
• High steam, energy and water consumption was noted during the
desizing, scouring, and bleaching processes.
• Some re-processing of fabric was required due to insufficient fabric
whiteness and uniformity of dyeing.

CP techniques implemented
Combined desize and scour – Misr Beida Dyers Company
Seven production trials were conducted to improve the efficiency of the com-
bined desizing and scouring process. Four fabric samples of 250–313 kg size
were treated on the normal wide jiggers and three samples of 750–850 kg size
were processed on the existing Vald Henriksen jiggers.
In the trials, concentrations and rates at which chemicals were added were
varied as well as temperature, number, and timing of washes. Initial problems
of attaining acceptable fabric wettability and whiteness index were eventu-
ally overcome. The final acceptable processing recipe for desize/scour fol-
lowed by half bleaching of 1 ton of fabric appears in Table 2.23.
®
Fabric quality after bleaching and dyeing with Cibachrome Orange ,
showed improved wettability and whiteness and consistent color properties.
A comparison of results is shown in Table 2.24.
In optimizing the modified combined process it was possible to eliminate
two hot washes in the half bleaching process. More expensive chemicals were
phased out and replaced with ammonium persulfate and Egyptol. Overall there
was a reduction in water, energy, and steam consumption. Processing cycle time
was shortened by 2 hours (18% reduction in processing time).

Combined scour and bleach – Giza Spinning and Weaving Company
Trials were undertaken to combine the scour and bleach processes more effi-
ciently and to phase out the use of sodium hypochlorite in bleaching. Hydrogen