1. SUBMITTED BY
VISHAL SINGH
MAE- II SEMESTER
00320903613
A REPORT ON
ENVIRONMENTAL IMPACT
OF TEXTILE INDUSTRIES
ENVIRONMENTAL STUDIES
ETEN-160
2. INTRODUCTION
The textile industry is a significant contributor to many national economies.
The Indian textile industry is no exception to this. It occupies a unique
position in the Indian economy in terms of its contribution to industrial
production, employment and exports.
It is closely linked with agriculture and rural economy and is the single largest
employer in the industrial sector, employing about 35 million people.
Here an attempt has been made to present an overview of Indian textile
industry in terms of its structure, problems associated with it, its impact on
environment, pollution control strategies.
Textile processing industry is characterized not only by the large volume
of water required for various unit operations but also by the variety of
chemicals used for various processes. There is along sequence of wet
processing stages requiring inputs of water, chemical & energy and
generating wastes at each stage. Large variation in demand of type, pattern
and color combination of fabric resulting into significant fluctuation in waste
generation volume and load.
Textile processing generates many waste streams, including liquid,
gaseous and solid wastes, some of which may be hazardous. The nature of
the waste generated depends on the type of textile facility, the processes and
technologies being operated, and the types of fibers and chemicals used.
3. EFFECTS ON ENVIRONMENT
Any industrial activity causes pollution in one form or the other and so is the
textile industry. This industry covers a wide spectrum of manufacturing
activities and is diverse in terms of raw materials and techniques employed,
chemicals used and the final products. The impact of textile production on the
environmental aspects such as air, water, land and human body, and the
social aspects such as child labour and poor unhygienic working conditions
must be considered.
Large number of chemicals in vast quantities are used in textile wet
processing to satisfy consumer's demands as regards aesthetics, handle,
imparting desirable properties, etc. Some of these chemicals, such as dyes
and finishing agents, remain attached to the textiles, whereas a substantial
proportion of these chemicals remain in the processed water, causing air and
water pollution. Air pollution is also caused during drying and polymerization
sequence of finishing operations. Many of the dyes and finishing agents
remaining on the finished fabric have been found to pose health hazards.
4. Air Pollution
Most processes performed in textile mills produce atmospheric emissions.
Gaseous emissions have been identified as the second greatest pollution
problem (after effluent quality) for the textile industry. Speculation
concerning the amounts and types of air pollutants emitted from textile
operations has been widespread but, generally, air emission data for textile
manufacturing operations are not readily available. Air pollution is the most
difficult type of pollution to sample, test, and quantify in an audit.
Air emissions can be classified according to the nature of their sources:
Point sources:
•Boilers
•Ovens
•Storage tanks
Diffusive:
•Solvent-based
•Wastewater treatment
•Warehouses
•Spills
Textile mills usually generate nitrogen and sulphur oxides from boilers Other
significant sources of air emissions in textile operations include resin finishing
and drying operations, printing, dyeing, fabric preparation, and wastewater
treatment plants. Hydrocarbons are emitted from drying ovens and from
mineral oils in high-temperature drying/curing. These processes can emit
formaldehyde, acids, softeners, and other volatile compounds. Residues from
5. fiber preparation sometimes emit pollutants during heat setting processes.
Carriers and solvents may be emitted during dyeing operations (depending on
the types of dyeing processes used and from wastewater treatment plant
operations. Carriers used in batch dyeing of disperse dyes may lead to
volatilization of aqueous chemical emulsions during heat setting, drying, or
curing stages. Acetic acid and formaldehyde are two major emissions of
concern in textiles.
Water Pollution
The textile industry uses high volumes of water throughout its
operations, from the washing of fibers to bleaching,
dyeing and washing of finished products. On average,
approximately 200 L of water are required to produce l kg
of textiles. The large volumes of wastewater generated
also contain a wide variety of chemicals, used throughout
processing. These can cause damage if not properly
treated before discharge to the environment. Of all the
steps involved in textiles processing, wet processing
creates the highest volume of wastewater.
The aquatic toxicity of textile industry wastewater
varies considerably among production facilities. The
sources of aquatic toxicity can include salt, surfactants,
ionic metals and their metal complexes, toxic organic chemicals, biocides and
toxic anions. Most textile dyes have low aquatic toxicity. On the other hand,
surfactants and related compounds, such as detergents, emulsifiers and
dispersants are used in almost each textile process and can be an important
contributor to effluent aquatic toxicity, BOD and foaming.
6. Solid Waste Pollution
The primary residual wastes generated from the textile industry are
non-hazardous. These include scraps of fabric and yarn, off-specification yarn
and fabric and packaging waste. There are also wastes 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, which
can often be reduced by increasing fabric utilization efficiency in cutting and
sewing.
PREVENTION
Air Emission Control
The conventional source of air pollution from a textile mill is boiler chimney.
These emissions normally consist of pollutants such as suspended particulate
and sulphur dioxide. Regulations often specify the type and composition of
the fuel to be used and the chimney height for satisfactory pollutant dispersal.
Air emission control methods commonly installed at textile mills include
cyclone separators, bag filters and wet scrubbers. Oil mists and volatile organic
7. carbon (VOC) are more difficult to control. Reductions can be achieved by
controlling the application of spinning oils and finishing agents to fabric.
Proper air ducting and the installation of mist eliminators are other important
control techniques.
Sludge Treatment and Disposal
During the biological treatment of effluent, sludge is formed. If the sludge
formed is small, it may be recycled or can be used in lagoons. In case of
substantial quantity of sludge, it may be subjected to aerobic digestion. The
digested sludge may be thickened by a gravity thickener. Supernatant from
this process should be returned to the aeration tank and thickened sludge may
be de-watered. The liquid taken off may be returned to rapid mix tank of the
chemical coagulation process. Sludge from the centrifuge is best disposed of
to a sanitary landfill facility on or off site.
Efforts Made by Government of India
• Prohibition on the use of 1 1 2 dyes, which are capable of releasing listed
harmful amines.
• Evolution of eco standards and logo for eco-friendly textiles.
• Organization of educative seminars,
workshops and camps to inculcate the eco-
friendly concepts among the industry and
consumer.
• Assistance to be provided by Textile Research
Associations and Textile Committee to textile
units for securing ISO 9000 Quality System
Certification and ISO 1 4000 Environment
Management System Certification.
