A Multiple-Objective Environmental Rationalization and Optimization for Material Substitution in the Production of Stone-Washed Jeans- Garments

As the Textile Industry is the second largest industry in Egypt and as small and medium-sized enterprises (SMEs) make up a great portion of this industry therein it is essential to apply the concept of Cleaner Production for the purpose of reducing pollution. In order to achieve this goal, a case study concerned with ecofriendly stone-washing of jeans-garments was investigated. A raw material-substitution option was adopted whereby the toxic potassium permanganate and sodium sulfide were replaced by the environmentally compatible hydrogen peroxide and glucose respectively where the concentrations of both replaced chemicals together with the operating time were optimized. In addition, a process-rationalization option involving four additional processes was investigated. By means of criteria such as product quality, effluent analysis, mass and heat balance; and cost analysis with the aid of a statistical model, a process optimization treatment revealed that the superior process optima were 50%, 0.15% and 50min for H2O2 concentration, glucose concentration and time, respectively. With these values the superior process ought to reduce the annual cost by about EGP 105 relative to the currently used conventional method.




References:
[1] M. Ilomaki, M. Melanen, "Waste Minimization in Small and Mediumsized
Enterprises - Do Environmental Management Systems Help?". J.
Cleaner Production 9 (2001), 209-217.
[2] KITA, APEC Virtual Center for Environmental Technology Exchange,
Cleaner Production by Kitakyushu International Techno-cooperative
Association, October 2004.
[3] J. Petek, P. Glavic, "Improving the Sustainability of Regional Cleaner
Production Programs", Resources Conservation and Recycling 29
(2000), 19-31.
[4] Unepi, "www.unepi.org/pc/cp/understanding_cp/home", UNEP, Cleaner
Production - Key Elements, December 2004.
[5] SEAM Programme, "A Guide of Cleaner Production, Opportunity
Assessments in Small and Medium Enterprises", September 2004, p. 6-9.
[6] D. Mahato, Denim Processing. J. Colourage, August 2005, 79-80.
[7] P. Kubelka, F. Munk, Tech. Physik, December 1931 p. 593.
[8] ASTM, D1682 - 1924, "Standard Test Method for Determination of
Tensile Strength".
[9] AATCC Test Method 39-1980, "Wettability of Fabric Method".
[10] ASTM, D4158 - 2001, "Standard Guide for Abrasion Resistance of
Textile fabrics".
[11] AATCC Test Method 66 - 1990, "Wrinkle Recovery of Fabric:
Recovery Angle Method".
[12] ASTM, D1388-1996, "Standard Test Method for Determination of
Stiffness".
[13] APHA, "The American Standard Methods for Examination of Water and
Wastewater", sections 5210B, 2540C, 2540D, 5220D, 1998.
[14] Z. Kafarov, S. Achnazarova, "Experiment Optimization in Chemistry
and Chemical Engineering", Mir Publisher, 1982, p. 151-158, 167-171.