Reuse 50/50 cotton/polyester

Figure 2. Dyebath reuse 50/50 cotton/polyester, high energy reactive/base-...

The final area of knit fabric research was adaptation of reuse to the coloration of 50/50 cotton/polyester blends. Several problems in addition to those already listed had to be attacked and solved before the process could be developed ... 

Savings and Cost/Benefit Analysis. The bench scale experiments were successful Tn overcoming major technical problems while demonstrating that dyebath/auxiliary bath reuse is indeed feasible with reactive dyes on cotton-containing fabrics. In addition, a shortened-cycle dyeing procedure coupled with reuse for cotton/polyester blends was shown to further increase energy, mass, and time savings (Table XXX). 

To construct a model plant for incorporation of the two-step dyebath/fixation bath reuse technique to the coloration of cotton/ polyester knits, several assumptions were made ... 

Table XXXII. Direct Savings in Two-Step Dyebath Reuse Coloration of Cotton/Polyester Knits Based on 3.6 x 10 Lb./Yr. Production...

Good lot-to-lot shade correlations were also obtained with reuse of low-temperature reactive dyebaths and fixation baths on 100% cotton, and with reuse of combined high-energy reactive/disperse dyebaths and fixation baths on cotton/polyester knit fabrics. Further computer program development is required, however, before industrial shades can be matched with the reactive dye reuse system. 

Fabric coveralls are designed to be cleaned after each day s use and reused. However, absorbent materials such as cotton, polyester, cotton blends, denim, and canvas cannot be cleaned adequately after they are drenched or thoroughly contaminated with concentrated pesticides labeled with the signal word "DANGER" or "WARNING". Always discard any such clothing or footwear. They cannot be safely reused. 

Mercerization is a process of treating cotton and cotton/polyester woven goods with 20% caustic solution under tension to enhance dyeability, appearance, and luster. The pollutant is wastewater of very high alkalinity or neutralization salts. This waste stream can be recycled through evaporative caustic reclamation systems, but that is rare in commerce. Another potential reuse strategy for this waste stream is scouring. 

Chlorination was found (172) to be the most suitable and effective method for decolori2ing and reducing the COD of waste dyebaths containing a2o dyes. These findings have been substantiated for chlorination and biochemical purification (173). A study (174) has been done on the technical and economic feasibiUty of a chlorination dye wastewater reclamation system for treating effluent that is suitable for reuse in dyeing of polyester/cotton blends with disperse and direct dyes. 

Fixation Bath Reuse to Combined Disperse/Reactive Dyeing of Polyester/Cotton Knit Fabric... 

Polyethylene terephthalate, also known as PETE or simply 1, is a form of polyester often used to make bottles and jars to contain food. When collected, it is ground up into flakes and formed into pellets. The most common use for recycled PETE is the manufacture of polyester carpets. But it may also be spun into a cotton-candy-like form that can be used as a fiber filling for pillows or sleeping bags. It may also be rolled into thin sheets or ribbons and used as tapes for VCRs or tape decks. Reuse to produce bottles and jars is also common. 

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