Tuesday, August 7, 2012

Eco standards in textile Industry through eco auditing

The growth in garment industry in India follows the same pattern as that in the Western World, where individual tailoring has slowly faded away and mass production of apparel has penetrated even the rural markets. The readymade garment market has boomed in the recent years. Garment production and quality control has gained increasing importance in the world. Customer/buyer awareness and competition will lead to further growth and strict quality parameters.

Product manufacturing and testing may be looked at under the following broad categories:
♦ Raw material specifications.
♦ Apparel end-use specifications.
♦ Performance specifications.
♦ Disposal of used products.

Today’s ecological requirements
Today in Europe, ecological and toxicity factors are gaining prime importance in the business of fabric and apparel trade. In 1992, Germany banned the use of metallic components in all consumer articles, which contained nickel. Soon thereafter followed restrictions on pentachlorophenol (PCP) and Azo dyes, which liberated banned Amines. Pollutants, Allegan & Carcinogens are now being severely restricted in the manufacturing of consumer goods sold all over Europe. Therefore, a proper selection of processes is essential in confirming to standards demanded by a customer.

Enzyme technology
Enzymes and enzyme technology are widely touted as the way of the future for many processing industries. Enzyme wash is a technique involving the use of enzyme products designed to produce a moderate level of abrasion without the use of pumice stones. Enzymes are organic catalysts highly specific both in the reaction catalysed and their choice of reactants. Enzymes' properties are:
♦ Physically, enzymes are of colloidal nature and chemically they are of the nature of proteins.
♦ Enzymes are complex and have high molecular weights.
♦ Enzymes are destroyed by high temperatures because proteins get denatured.
♦ Enzymatic reactions are reversible.
♦ The activity of enzymes is limited to a narrow range of pH.
♦ Enzymes are inhibited by cyanide, sulphides, azides, etc.
♦ The range of specificity varies in different enzymes.

Water in textile wet processing
The textile industry consumes large amounts of water in its varied processing operations mainly for two purposes: First as a solvent for processing chemicals and secondly, as a washing and rinsing medium. Successful results in the textile wet processing are strongly dependent on a clean and consistent supply of good quality water.

Water consumption
Amount of water consumption in the wet processing depends up on the following factors:
♦ Machine design
♦ Complexity of process
♦ Method of process
♦ Nature of operation

Tolerances for water for textile industry
Quality of water required for textile industry depends on the location, available sources like river water, sea water, bore water, etc. That means different sources of water having different levels of contamination like presence of metallic parts, salt level. Organic, inorganic content which affect the tolerance limit for the textile wet processing. Table 1 shows the tolerances limit for bleaching and dyeing operation in cotton wet processing industry and also mentioned for wool scouring processing industry. The factor which affects the quality of water in the textile wet processing and consciousness to be taken in these areas is shown in Figure 1.

Efficiency of enzyme
The efficiency of enzyme reaction depends up on the following factors, which are shown in Figure 2.

Eco-auditing
Eco-auditing is a systematic, documented and objective view of the facility, operations, practices and products and related to meeting environmental requirements. It is the assessment of the textile industry with regard to their conformance with the norms or criteria of certain eco-parameters that are required for maintaining eco-standard.

Eco-criteria
The eco-criteria for textile products are built around three key areas:
I. Environmental requirements concerning the fibre types used.
II. Environmental requirements concerning the processes and chemicals used in the production of textiles.
III. Requirements concerning the usability of the final textile products.

Keywords to meet eco-criteria:
Due to the various keywords to meet eco-criteria, the following possibilities may arises.
1. To analyse eco-pressures on the industry hence impact possibilities to soil, air and water.
2. Environmental auditing of all inputs, including raw materials used chemicals and dyes.
3. An action plan should be developed to interpret the results of chemical audit.
4. Substitution of chemical and dyes.
5. Laboratory bench testing.
6. Pilot test testing.
7. Production scale testing.
8. Process optimisation.
9. Development of a quality assurance system and quality assurance manual.

EU Eco-audit: This system lays down 9 requirements to be fulfilled for acceptance of a place and a concern:
♦ Carrying out eco-analysis.
♦ Laying down basis for eco-analysis.
♦ Introduction and maintenance of an eco-management system.
♦ Laying down aims of eco-management.
♦ Carrying out necessary eco-analysis tests.
♦ Setting up an ecology programme.
♦ Preparing an ecology situation statement.
♦ Testing of confirmation to above statement.
♦ Handing over such an ecology statement to the relevant authorities and entry in the local Eco-register.

Quality assurance system: The quality assurance manual must provide the following information:
♦ Dyes ad pigments along with their CI number
♦ Chemicals in use
♦ Material safety data sheets for all items
♦ Processing methods used
♦ Quality parameters of the final product
♦ Test methods for each of the items
♦ Frequency at which each test needs to be conducted
♦ Eco-label requirements

Profit of Eco-audit: By introducing the eco-audit in textile wet processing industries, the following benefits are obtained:
♦ Cost reduction due to systematic analysis from material input to delivery at every stage of processing
♦ Legal safety
♦ Improvement of the environmental protection within the industry
♦ Improvement of reliability
♦ Improvement of acceptance within the official and the public

Eco-labels

Buyers in the Europe markets frequently ask for certification of common eco-labels. Eco-labels are basically of two categories, those which are Government administrated and other which are commercially introduced. Some of these labels are given in Table 3.

Some labels have special requirements that the processor will need to understand what the customer/buyer needs before deciding processes, process parameters and dyes & chemicals that should be used.

Steps for achieving Eco-label award:

♦ Management commitment.
♦ Selection of eco-label product lines.
♦ Establishment of factory implementation team.
♦ Preparation of process flow diagram.
♦ Eco-audit of chemical & dyestuff.
♦ Process optimisation.
♦ QA system & QA manual.
♦ Award of eco-label certification.

Measures to over come problems associated with waste water quality
♦ Colour of process water can be removed by flocculation and filtration method where it is treated with alum (aluminium sulphate), and lime or soda ash.
♦ Metallic impurities can be removed by aeration, coagulation with alum settling and filtration. However some of the waters require special treatment.
♦ Membrane filtration, ion exchange and electrolysis can remove sulphate and chlorides.
♦ Silica-scale growth in process water can be prevented using scale inhibitors of good dispersants.
♦ Silica can be removed through reverse osmosis (RO) and ion exchange techniques, as well as disilicisers. RO membranes are not immune to silica scale, which forms as a gelatinous mass on the membrane surface. It then can dehydrate, forming a cement like deposit.
♦ Water hardness can be removed by ion exchange method. This is commonly referred as ‘Zeolite Softening’. Hardness can also be removed by treatment with lime and soda ash; This is known as ‘Soda-Softening’.
♦ Turbidity can be removed by clarification using alum and soda ash or lime followed by filtration.

The future in textile requirements
Quality parameters and specifications in the future are expected to investigate the complete “Eco-Cycle” or “Life-Cycle” of a textile product. Bio-degradable products will need to be produced to replace the ones that are to be phased out. Human rights concerns, socio-economic issues such as child labour, work environment and occupational hazards will need to be effectively addressed.


References
1. Lopmundra Nayak, and P S Nayak: A Part of Ensuring Eco-Standard, Clothesline, July 2004.
2. Edward Menzes, and Dr Bharat Desai (Rossari Biotech): Water in Textile Wet Processing -- Quality and Measures, Clothesline, 2004.
3. Eskel Nordell: Water Treatment for Industrial and Other Uses, 1951, Reinhold Publishing Corporation, New York.
4. Paul Roshan and Naik S R: Textile Dyer & Printer, 1997, 13.
5. NCUTE programme on Finishing of Garment & Knits, 2001.
6. Dr G P Nair: Developments in Garment Finishing Machinery.
7. D V Alat: Enzymes in Garment Finishing.
8. Dr R B Chavan: Eco-friendly Specially Chemicals in Garment Finishing.
9. Dr Ulhas Nimkar: Quality Control and Testing in Garment Finishing.
10. Achwal W B: Colorage, 40 (11) (1993), 23.
11. Lantto R, Miettinen and Suominen: American Dyestuff Reporter, 85 (1996).
12. S Perkins: Dyeing and Finishing, Asian Textile Journal, 1997, 72-74.
13. Nalankilli G: Application of Enzymes in Wet Processing of Cotton.
14. Nalankilli G: Indian Textile Journal, C3 (12) Sep 1992, 110.
15. www.rossari.com, www.biocon.com, www.yogeswarchemicals.com.
16. www.texanlab.com.