40 Solid waste management in textile industries

R. Sunitha

Learning Objectives

To understand about of recycling of textile solid waste To impart knowledge about textile waste management

1. Introduction

The products which are produced from textile industry have some kind of impact on the environment. This may be hazardous some times. Textiles are made from various functions and are made up of different types of fibres, mixed in varying propositions. The application of fibres can be classified in three categories: Apparel, Home furnishing and industrial most of the fibre products are short term to medium term use, enduring up to few years in their service life. Textile waste unit is persuaded by the production of textile goods, higher the production, the greater the amount of waste. The growing consumption of products is an indicator of the increasing amount of waste generated in the world, which has increased environmental awareness and social responsibility, reinforced by strict legislation in developed countries, leading to the creation of more efficient waste management practices. Textile solid waste (TSW) belongs to the industrial and non-dangerous wastes and is defined as “waste of raw material referred to as fabric trims, scraps or parts rejected by defects” in manufacturing processes of the clothing industry. Producing textiles is an environmentally damaging process. It consumes large quantities of natural resources, like water, oil and they use toxic chemicals and generate large amounts of carbondioxide.

Green consumerism has stimulated industries to promote an environmentally correct image to the public. Excellence program requires mills to set up awareness and action programs. The apparel manufacturers have instituted environmentally correct production processes and recycling programs.

2.Waste

Waste is defined as any product or substance that has no further use or value. It is perceived to be a problem for they harm the environment and human health, take up space for landfills and that the costs are increasing to use existing and replace landfills and these are end of product lifecycle that causes environmental impacts and depletes the valuable resources.

2.1. What is textile waste?

The wastes from the textile community through various streams which includes fibre industry, and clothing manufacturing industry, consumers, commercial and service industries. The wastes can be of three kinds namely pre-consumer, post-consumer and industrial textile waste.

2.1.a. Pre-consumer textile waste

Pre-consumer textile waste is the leftovers or by-products from textile, fibre or cotton industries. Pre-consumer textile waste is nothing but the manufacturing waste which is generated by processing of fibres, production of finished yarns and textiles, technical textiles, nonwoven, garment and footwear, including off-cuts, selvages, shearings and rejected materials. Pre-consumer textile waste is usually “clean waste”. It is generated by retailers primarily in the form of unsold merchandise. The unsold merchandise may be sent directly to their own outlets or clearance centers. The textile waste can directly be sold to outlets, or to jobbers or consolidators who in turn resell the merchandise to other outlet stores. Another disposal option is to send the textile wastes directly to non-profit organizations. The last option open to retailers is sending the textile waste directly to landfills. But this method is the least used as the waste still has resale value.

2.1. b. Post-consumer textile waste

Post-consumer textile waste is the waste of fleece, flannel, corduroy, cotton, nylon, denim, wool and linen, which have passed through the consumer market.  It consists of any type of garment or household textiles such as sheets or towels which are discarded by the consumers for the reasons that they are worn out, damaged, outgrown, or have gone out of fashion. This category may be reasonable to good quality garment that can be recovered and recycled by another user as second-hand clothing. Clothing that cannot be worn again may be shredded into fibres to be used in products.

These items are given to charities sometimes and put in trash which ends in landfills. Of the amount about held is recycled as second hand clothing. Nonprofit organizations use around 40 percent of the estimated collected goods. The balance is sold to rag graders and export companies. The company who is a textile recycler and exporter primarily purchases from non-profit organizations then processes and sells about 8,000 tons of post consumer textile waste a year. This company handles different kinds of clothing, rags, and wipers and recycles over 96 percent of the textile waste they receive.

2.1. c. Industrial textile waste

Industrial textile waste is obtained from commercial and industrial textile applications including commercial waste from properties such as carpets and curtains, hospital refuse in addition to industrial applications such as filtration, conveyor belting, etc. Industrial textile waste is dirty waste. A substantial proportion of these end-of-life goods are consigned to landfill.

The vast majority of the solid waste stream is contributed by the post producer waste from industry. Total post-consumer solid waste accounts for only 2 percent of the nations total annual output of 11.7 billion tons. The textile waste worth to 1.5 and 1.9 billion pounds of new fibre and fabric wastes are generated annually by the fibre producers, textile mills and fabric manufacturers. Of this, total apparel manufacturers contribute 450 to 600 million tons annually in the form of apparel cuttings.

3. Sources of Textile Waste

Majority of textile waste comes from household sources. The clothes discarded as they become unfashionable, or undesirable. These are post-consumer waste that goes to jumble sales and charitable organizations. The household textiles coming to these organizations, are sold or donated. The remaining goods go to either a textile recovery facility or the landfill. Textile waste also arise during yarns and fabric manufacturing, apparel-making processes and from the retail industry. They are the post-industrial wastes. Apart from these textile waste other wastes such as PET bottles are also used for recycling polyester fiber.

Waste from textile industry includes fibers damaged during storage or manufacturing. Major solid waste from, garments industry factories comprises fabric waste from garment cutting amounting to 10 to 20% of fabric consumption. The sources of these solid hazardous wastes include waste solvents from machine cleaning unused finish materials and dying and printing materials. Some of these hazardous materials include metallic chlorinated solvents.

Textiles manufacturing processes like warp preparation, weaving, dyeing, printing, finishing, and quality and process control, generates lot of waste during these process. The major wastes generated by this sector are fiber wastes, yarn spinning waste (hard Fiber), off cuts waste, packaging and spool. The data of metropolitan city like Bangalore in 2012 show that it the maximum waste of 36% is from apparel and 34.4% from fabrics. Other 15.2 % of solid waste is of resins, 12.2% contributed by fiber and 2.3% from dyes .

Industrial process and waste include scrap of fabric and yarn. These are wastes are associated with the storage and production of yarns and textiles such as chemical storage drums, cardboard reels for storing fabric and cones used to hold yarns for dyeing and knitting. Cutting room waste generates a high volume of fabric scraps. The majority of this waste originates from other sources during operation such as transportation, bale openings , servicing process, house keeping etc. These wastes can be recycled .

Lint wastes can originate from many textile production steps particularly from preparation dyeing and washing operations. The lint removal is easy by filtration process. The filters must be cleaned periodically. The collected lint may be sent to landfill or incinerated. Higher quality lint can also be marketed.

4.Effects of Solid waste

Another product of decomposition in landfill is methane gas, which is a major cause of greenhouse gases which contributes to global warming. The decomposition of organic fibres andyarn such as wool produces large amounts of ammonia as well as methane. Ammonia is highly toxic in both terrestrial and aquatic environments, and are toxic in gaseous form. Cellulose-based synthetics decay at a faster rate than chemical-based synthetics. In the past textile waste has been incinerated in large quantities, emitting organic substances such as dioxins, heavy metals, acidic gases and dust particles, which are all potentially harmful to both humans and the environment.

Waste minimizes options include reducing the quality of packing material, purchasing chemicals in returnable drums and purchasing yarns on reasonable loans.

The need to reduce waste supply is necessary due to its accumulation. However, this process is considered long-term period, which requires proper management in the short and medium term, avoiding environmental and health problems for humans. As far as the medical textiles is concerned,

The Problem of Disposable Waste is that the reusable surgical textiles are demonstrating increased clinician satisfaction while also providing comparable barrier protection. And reusable table and covers, surgical towels, etc drive down costs by reducing the volume of waste generated. Reusable Isolation Gowns Can Reduce Waste by 80% and Can Cost Up to 50% Less than Disposables. Reusable isolation or barrier gowns are engineered using microfiber technology that produces 100% polyester, tightly woven, and fluid-repellent fabric made of continuous filament threads. Isolation gowns: Protect healthcare workers from blood and bodily fluids, Provide comfort and allow for sterilization, Are available in several levels of protection, On the other hand, single-use, disposable isolation gowns generate five times more solid waste than a reusable product. Reusable Surgical Packs Decrease Waste and Costs when the comparison is made between the laundered packs and the disposable surgical packs which are thrown in trash in lots. There will be an Increase in Use of Reusable Surgical Gowns and Drapes as these seem to be cost effective as they don’t cause much wastes on land.

5.   Recovery of textile waste

 The practice of recovering textile waste is old technique. The recovery units are gaining so much of importance these days mainly in foreign countries. At the time there were 80 firms employing a total of 550 people sorting the rags. Today, recovering textile waste is a multi-billion dollar global industry that performs a vital social and environmental function and provides employment for millions of people all around the world. The textile waste from

products or listings, including headings such as hosiery cuttings and clips, polyester tow, cotton shoddy, used clothing wiping rags, denim/jean clippings, 100% cotton yarn waste, silk fibre waste can be utilized. Collection is mostly of post-consumer waste by means of community donations deposited into charity bins, thousands of which are located across Tirupur, and/or drop-offs directly to charity shops. The vision of every organization and municipality is to recycle all of its waste into usable products.

5.1. Recycle

Textile recycling should be done for both, environmental and economic benefits. It avoids many polluting and energy intensive processes that are used to make textiles from fresh materials. The Council for Textile Recycling reports that each year 750,000 tons of post producer textile waste is recycled into new raw materials for the automotive, furniture, mattress, course yarn, home furnishings, paper and other industries. Reports say that 73 percent of the post producer fabric waste recycled annually, approximately 150 million pounds are reprocessed in to fibre 200 million pounds are sorted for colour and exported to be respun and 100 million pounds are used to make wipers. About 75 percent of post-produceer textile waste is recycled instead of disposed in landfills.

The requirement of landfill space is reduced. Textiles lead to many problems in landfill. The synthetic fibers do not decompose. Woolen garments do decompose but produce methane, which contributes to global warming.

Pressure on fresh resources too is reduced.Leads to balance of payments as we buy fewer materials for our requirements.As fibers get locally available, they don’t have to be transported from abroad thus reducing pollution and saving energy.Lesser energy is consumed while processing, as items don’t need to be re-dyed or scoured.Waste water reduces as it does not have to be thoroughly washed with large volumes of water as it is done for, say, raw wool. Demand is reduced for textile chemicals like dyes and fixing agents.

Textile recycling is the reuse or reproduction of fibers from textile waste. The worldwide recycling industry performs important social and environmental functions. The various stages of the recycling process provide significant employment around the world. The garment or household textiles can effectively be recycled by sale or gift to another user. The UK-based Recycling Association estimates that up to 95% of the textiles that are land filled each year could be recycled. Of the textile waste recovered by the charities, 60% is items of clothing that can be re worn or reused and 15% can be torn into industrial wiping and polishing cloths.

Cotton can be used for making rags or form a component for new high-quality paper. Knitted or woven woolens are brought to the state of fiber for reuse by the textile industry and are used for car insulation or seat stuffing. Other kinds of fabric are reprocessed into fibers for upholstery, insulation, and even building materials. The fasteners used are taken off for reuse. If all available means of reuse and recycling are properly utilized, only about 5% of the remaining solid waste needs to be disposed of.

5.1. a. Methods of Recycling

The simplest method of recycling scrap is by granulating but this produces a product which in most cases is impossible to reuse directly into the primary manufacturing process of fiber. It is noisy and dirty with much dust, the scrap cannot be filtered to remove the impurities. The standard method of extrusion is by melting, filtering and pelletizing. Scrap can not be fed directly into the extruder and needs to be put through a granulator first. This gives problems because the often light fluffy material is degraded due to high shear and heat, the process is dusty and noisy and energy usage is high – semi- or fully automatic aggregators.

THE EREMA PROCESS extrusion process is dust free, has a low noise level, occupies a small space, gas low energy usage and generates low maintenance costs. It can produce clean, full bulk density, filtered pellets with little or no degradation directly from PP,PE,PET film, fiber or scrap bottles at a high output and low operating cost.

The high performance which is independent of the shape and bulk density of material to be processed, results from EREMA concept of using a shredder drum attached to an extrudes. The shredder drum is continuously fed, with the rate being automatically controlled by the load on the shredder motor which drives high speed rotary knives that not only cut the material but also heat it to just below its melting point. This hot material is then fed into an extruder which melts the material and passes it through a filter to remove contaminants and then into water cooled die head to produce pellets which are dried, stored or bagged. Since the material is fed got into a short extrudes, the screw is designed with deep fight which produces little or no shear. This provides a maximum heat history which results in little or no change in the melt index. The quality of material is such that it can be used in higher value added products. In the conventional extrusion, material is heated primarily by shear from the extrusion screw, which causes considerable degradation of polymer and a high energy usage.

These particles may be used in a number of ways such as filling for cushions or bags, for upholstery, for packing, manufacturing mats and in the automotive industry.

Upholstered furniture comprises of non-woven textile with a number of bonding degrees. They are also set up as textile cover material non-woven used in areas well below the surface are made from reclaimed fibers. They are of eco interest with respect of recycling. Usually these are prepared from white primary fibers.

5.2.Regenerating textiles

All textile waste streams are often un realised sources of valuable raw materials that can be regenerated. Processing machinery is also likely to be engineered to produce a specific product and thus the investment in developing regenerating capabilities is often large-scale. Products made by regenerating textile waste include acoustic textiles used for sound proof blocks, insulation, roofing felt, bank stabilisation, and as pollution control filters.

6. Barriers to recovering textile waste

There are numerous political, economic, social, technological, environmental, legal and institutional barriers to the improvement of resource recovery in certain places. They are

Knowledge, Finance, Research and development Community awareness and Facts and figures.

One of the barriers faced by the company and is in search through design and product development, is consumer resistance against innovations, such as recycled yarn.

7. Solid waste management

7.1 Levels for Waste Management

“Management” means managing things for utilization of resources in best manner, which can help to save time, cost and resources.

Waste can be managed at two levels i.e. 1. Industrial level 2. Household level 7.11.

Waste management at Industrial level:

Non hazardous Textile Waste at Industrial level generally includes fibers, yarn, cut off fabric pieces, defective fabrics with construction, extra fabric cutting, contributed by various industries and factories. 10-15% of Waste produced by industries is hazardous and the generation of hazardous wastes is increasing at the rate of 2- 5 % per year.

Pure white cotton fibers may be converted to superabsorbent polymers by chemical modification and can be used for production of medical textiles i.e. in diapers.

With low quality material, there is another possibility for developing super absorbent agro- textiles for water storage and controlled water release for plantation in arid or desert land. It may be possible to produce cellulose in the powder form, which can be used as fillers, or for blending with other polymers for developing composite materials.

Wool Fibers normally recycled by blending with new wool to produce new textile product .The final product may be little harder, but surely long lasting.Polypropylene which is widely used in the production of sport wear can be reprocessed by producing pellets/ master batches and further molding into different plastic component.

Sludge management in textile industry is major problem due to its surplus volume. Typically solid waste management is mainly to remove the waste by carrying them out of the city boundaries and dumping them and there. Steps have been taken to utilize these wastes for converting it into useful low cost bricks. Textile sludge has a variable composition and contains high organic matter, N, P, K and micronutrients contents. In addition dyes, heavy metals and pathogenic microorganisms may be presented.

Composting may be done for utilization and transformation of these wastes in the soil improvement. During the composting, the plant nutrients present in the wastes are converted by microbial action into soluble forms, available to plants. Composting also decreases or eliminates the toxicity of textile sludge. Vermicomposting is commonly used for the management of organic wastes. It was investigated that the potential of an earthworm, Biological treatment with activated sludge was found to be more efficient and reliable in terms of organic matter removal than chemical coagulation for the treatment of textile‐processing industry waste.

Benefits of reducing Wastes at Industrial level

i. Reducing the cost of purchase material (e.g.: by maximizing fiber use).

ii.   Increasing profitability (as lost product means less profit).

iii.   Minimizing Solid Waste treatment and disposal costs

iv.   Improving waste quality and reducing treatment costs.

v.   Reducing environmental impacts by reducing use of raw materials and producing less waste.

7.1.2 Waste management at Household level:

Hazardous waste at household level generally includes products like paper, aluminum cans, metals, steel cans, tires batteries thrown by the local public.

actors at household level contributing to the environment pollution:

Increased income: With the increase in income, luxury budget of individual have increased which has lead to more discarded clothes contributing to textile waste. Dynamic nature and fashion: Because of this nature of the fashion, people tend to discard clothes more often to acquire new fashionable garments Worn out clothes: Normally worn out clothes are discarded without any recycling or reuse

Suggested measures at household level:

Formal Reuse Waste can reduce by reuse of the clothes e.g.: It can be handed over to second hand shop or to the needy people who cannot afford new clothes.

Semi- Formal Reuse i.e. selling on website e.g.: children inherits clothes from siblings, friends sharing clothes Making products by reusing discarded fabric or clothes

Waste minimization actually offers the best possibilities for environmental aspect of sustainable development by reducing resource use and avoiding production of waste. Recovery trade and recycling activities are the steps in the waste management. An important difference in evaluating the value of such waste flows is that made between unmixed sources of waste.

Conclusion

So textile industry is one of the most polluting industries. Not only production but consumption of textiles also produce waste. To overcome this problem, textile industry has taken many measures towards environment. Textile waste recycling will become ever more important. The engineers are trying to innovate economical recycling processes, which, also included the textiles field. There is the opportunity to develop knowledge networks to develop pre-consumer waste and resulting products. Maximizing waste diversion towards recovery and recycling is the waste primary environmental goal at this point is not well developed among the local authorities and citizens. Rather there activities take place mainly in a private market content. Therefore,evaluating value is currently the only method we can use to expect to what extent recovery of waste materials is likely to increase when then incentives are changed.

With growing attention to environment responsibility towards solid waste management the textile and apparel industry has expanded its efforts to reduce disposal of post-producer textile waste in landfills.Consumer education must be encouraged to stimulate an appreciation fo the value of textile recycling to the environment as well as to one’s own personal economy. They should be informed on different types of textile products conducive to recycling benefits of recycling certain apparel items and potential outlets for disposing of textile products.

Web links

• https://en.wikipedia.org/wiki/Management
• https://en.wikipedia.org/wiki/Training
• whatis.techtarget.com/definition/quality-control-QC