VERSION 1.

0 MARKS & SPENCER MAY 2011

ECP
MODULE 4 :
Environmental Management

VERSION 1.0
MAY 2011

ENVIRONMENTAL & CHEMICAL POLICY FOR TEXTILE PROCESSING

 VERSION 1.0 MARKS & SPENCER MAY 2011

MODULE CONTENT
Introduction ............................................................................................................................... 3
1. Effluent ............................................................................................................................. 4
2. Reduction of Effluent Loading ........................................................................................ 6
3. Air Emissions ................................................................................................................... 8
4. Solid Waste ...................................................................................................................... 9
5. Reducing Water, Energy And Chemical Consumption ............................................... 10
5.1 Reducing water consumption....................................................................................................... 10
5.2 Reduction in Energy Consumption .............................................................................................. 11
5.3 Compressed Air ........................................................................................................................... 12
6. Best Practices for Eco-Factories .................................................................................. 13
6.1 Leak detection and preventive maintenance, improved cleaning ................................................ 13
6.2 Reuse of non-contact cooling water ............................................................................................ 13
6.3 Reuse of steam condensate ........................................................................................................ 13
6.4 Reuse water from pre-treatment processes ................................................................................ 14
6.5 Recover heat from hot rinse water ............................................................................................... 14
6.6 Pre-screen coal ............................................................................................................................ 14
6.7 Maintain steam traps .................................................................................................................... 14
6.8 Insulate pipes, valves, and flanges .............................................................................................. 14
6.9 Recover heat from smokestacks.................................................................................................. 14
6.10 Electricity Saving from Compressed Air .................................................................................. 15

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INTRODUCTION
Reducing the impact of Marks & Spencer products the environment is a corner stone of Plan A. Poorly
managed dyehouses, printers, laundries and tanneries can be one of the biggest causes of damage to the
environment and have a great effect on the availability of natural resources such as water and energy.

However, Marks & Spencer believe a well managed factory, which employs some very simple and straight
forward principles can dramatically reduce its impact on the environment as well as improving its
efficiency and quality of production. Some of these principles have been touched on in Module 3:
Minimum Standards and Best Practice. Module 4 has been designed to build on the information and
guidance in Module 3 and to outline the principles Marks & Spencer expect of its suppliers with regards to
environmental management and minimising the use of natural resources.

The most important step for any organisation to reduce its impact on the environment is to measure its
current impact. Marks & Spencer expect its suppliers to be able to measure its consumption of key natural
resources such as water, electricity, fuel, dyes and chemicals. The collection of this simple information will
help identify where the biggest opportunities for improvement and saving can be made.

As a minimum requirement it is mandatory that all mills in the Marks & Spencer supply chain meet the
local environmental consent limits for water, air and solid waste disposal and have certificates and test
results to demonstrate ongoing compliance. Marks & Spencer consider one of the most critical aspect of
environmental management is for all effluent to be treated in a fully functional effluent treatment plant
(ETP) before being discharged. Marks & Spencer will not do business with mills that discharge untreated
effluent directly into water courses.

ISO 14001 is a very robust environmental certification and you are encouraged to consider this for your
factory:
www.iso.org/iso/iso_catalogue/management_standards/iso_9000_iso_14000/iso_14000_essentia
ls.htm

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1. EFFLUENT
Minimum Standards Requirement
Untreated effluent must never be discharged
All effluent must be treated in a fully functional effluent treatment plant (ETP) before being
discharged
The capacity of on-site effluent treatment plants must be sufficient to process the total factory
effluent output
Chemicals must not be allowed to contaminate soil
No chemicals can be washed down surface water drains
Confirm no breaches of consent limits in past 12 months
Confirm no prosecutions in the past 12 months
Mills must be fully compliant with local and national laws and standards
Mills must measure the following parameters: COD/BOD, pH, Temperature, Offensive colour,
Suspended solids, Total Dissolved Solids, Specific metals and toxins.
Treated effluent must be tested on a frequent basis in an independent laboratory and records
must be available for inspection.
Records of independent test results of effluent must be retained for at least 12 months

Effluent from textile colouration is viewed as the biggest source of pollution and environmental damage in
the supply chain when it is not correctly managed. The Marks & Spencer policy with regards to effluent
control have been in place for many years and are designed to ensure that any mills supplying Marks &
Spencer comply with the local and national laws as an absolute minimum. Marks & Spencer will not do
business with any mill which discharges untreated effluent directly or indirectly into water courses
(including rivers, lakes, ground water etc).

All effluent must be treated in a fully functional effluent treatment plant (ETP) before being discharged.
Effluent can be treated on-site, in a communal plant or in a municipal ETP. However, the factory must
clearly demonstrate how and where their effluent is being treated. If a factory is using off-site ETPs, the
factory is responsible for ensuring the ETP is compliant with local, national and Marks & Spencer
requirements.

Marks & Spencer do not publish one global standard for effluent treatment. However, the minimum
requirement for any factory supplying Marks & Spencer is that they are fully compliant with their local and
national laws and standards. As a minimum standard it is expected that factories take action to ensure the
following effluent parameters are measured and controlled.

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How to reduce the

Parameter What it is? Where is it found?
impact
All chemicals and dyes
COD / BOD Chemicals which require oxygen contribute to BOD/COD.
(Chemical / Minimise chemical usage
to break them down. High content Waxes and oils removed
Biological and select low COD/BOD
Oxygen results in depletion of oxygen from from natural fibres and fats
alternatives where possible.
demand) natural water courses. removed from hides have
high impact.
Processes that use
Excessive acidity or alkalinity that Effluent must be balanced
extremes of pH e.g. acidity
pH can affect the natural balance and neutralised unless there
from wool dyeing, alkalinity
within water courses. is consent.
from reactive dyeing.
Temperature must be
Releasing excessively hot or cold Chillers and heating
balanced – discharging
Temperature effluent into natural water courses systems. Any process using
boiling water or cold water is
can adversely affect eco-systems. or creating hot or cold water,
not acceptable
Colour is mainly a cosmetic
problem but excessive colour can Use higher fixation dyes and
Offensive
reduce the amount of light that Unfixed dyes use effective colour removal
Colour
gets to plant life – and some dyes in effluent treatment.
are toxic to aquatic life
Improve dust extraction in
TSS (Total Solid insoluble debris that can be factory processing (e.g.
Suspended ingested by aquatic species or Loose fibre and pumice dust vacuum slots) use effective
Solids) settle as silt on river or lake beds. filtration as the first stage of
effluent treatment
TDS is a measure of the amount
Optimise dye methods to
TDS of salts dissolved in effluent. This
reduce salt consumption.
(Total can kill many forms of life that can Salt from reactive dyeing.
Reverse osmosis is the only
Dissolved only survive in fresh water and
Solids) effective means of reducing
have a severe impact on drinking
TDS in effluent.
water.
Screen dyes and chemicals
Various contaminated textile
Specific Toxins can kill wild-life and for contamination. Apply
dyes and chemicals.
metals and seriously affect drinking water known toxins from zero
Mothproofing, anti-
toxins supplies discharge closed loop
microbials
systems

Where policing and certification of effluent controls is not implemented by local or national authorities,
Marks & Spencer require mills to have their treated effluent tested on a frequent basis (preferable
monthly) in an independent laboratory and records must be available for inspection.

Effluent must not be placed down surface water drains as this may bypass the ETP or contaminate the
local soil or groundwater. It is not uncommon for operatives who are cleaning old chemical drums and
containers to wash chemical residues down surface drains. This example of bad practice can lead to
environmental hazards and put the factory in risk of prosecution and loss of Marks & Spencer business.

It is recommended that factories should ensure the total capacity and rates of effluent treatment of the
ETP are in excess, or at least matching, the total discharge and rate of effluent production of the mill. If
the rate of production of effluent is approaching the limit of the ETP capacity then action is required to
either reduce the demand on the ETP or make investment to expand its capacity.

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2. REDUCTION OF EFFLUENT LOADING

The cost of effluent treatment is related to the volume of effluent and the concentration of chemicals
contained in that effluent. The best ways to reduce effluent loading, and therefore, the best ways to
ensure consent limits are not breached are:

 Reduce water consumption to reduce the volume of effluent

 Reduce chemical usage and increase dye fixation to reduce the total effluent loading
 Use low impact chemicals to minimise loading for COD, BOD, TSS etc

Where technical performance is similar, it is

commercially sensible to use products that are
easily removed from the effluent or have the
lowest contribution to COD, BOD, TSS, etc. For
example, formic acid contributes less to COD than
acetic acid and can be used in its place in many
wet processing facilities. The use of controlled
dosing and pH measurement systems will also
help to minimise the total amount of acid used.

Chemical choices should not be made on the

basis of biodegradability alone.

It would be irresponsible to use biodegradable products which are less effective or inconsistent in meeting
the required standards, and therefore, lead to increased levels of re-dye and re-processing, with
associated increased water and energy consumption.

Although colour in effluent is a largely cosmetic issue it can create an impression that effluent controls are
substandard and therefore colour discharges should be avoided. Where ever possible use dyes and
processes that give high levels of fixation. This not only reduces colour in the effluent, but could also help
to reduce the number of wash off stages, leading to lower water consumption, improved productivity and
lower costs. Bi-reactive dyes, for example have a higher affinity than average dyestuffs. As more dye
adheres to the fabric, less dye is used, less auxiliary chemicals are used, less rinsing is required and the
amount of colour in the effluent is reduced.

Salt is used in large quantities for reactive dyeing of cotton and it passes through effluent treatment plants
into water courses without being affected. It is recommended that steps are taken to minimise salt
consumption via the use of low salt reactive dyes.

One of the most important and cost effective ways to reduce effluent loading is to improve the quality and
consistency of the dyeing and finishing process. This reduces the amount of unnecessary re-dyeing and
re-processing, improves productivity, on time delivery and customer satisfaction.

A holistic approach to effluent management is zero discharge or water recycling. If the treated effluent is
clean enough to use in factory processing then it should not be discharged. This can reduce the cost of
waste management, reduce water extraction costs and protect the local environment.

Additional best practices that can be used to improve the control and treatment of effluent include:

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 Maximise filtration of solid materials

 Biological treatment is an energy intensive process but the use of AC blowers rather than DC
blowers can reduce energy consumption
 Carefully dose flocculants to minimise solid waste and consider non-chemical methods of colour
removal such as ozone to reduce solid waste
 Avoid the use of chlorine to remove colour

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3. AIR EMISSIONS
Minimum Standards Requirement
Confirm no breaches of consent limits in past 12 months
Records of independent test results must be retained for at least 12 months
Air quality must be satisfactory throughout factory
Appropriate PPE must be provided and worn

Air Emissions are often considered to be less significant than water pollution. However, climate change
and the increased use of performance finishes have raised the importance of air pollution. Control of air
emissions is important for both environmental and worker safety reasons, as fumes, dust and smoke can
create serious health issues. It is normal for local authorities to have strict standards for air emissions and
factories must be in possession of the appropriate certification to demonstrate compliance.

It is important to ensure boilers, generators and any other pieces of equipment that burn fuel meet local
consent limits for air emissions. It is also important to explore how the factory can improve its efficiency to
reduce the total amount of fuel used as this has a very direct impact on air emissions not to mention
costs.

Fumes and particulates from the exhausts and chimneys are traditionally difficult to manage, but the
development of modern scrubbers to remove noxious gases and particles can help ensure consent limits
are met.

For the safety of workers air extraction devices should be employed at the source of any fumes or
particulates in the factory. For example, the dust generated by brushing, sueding or the weighing of
powdered dyes should be extracted at these points in the factory. All dust or particulates that are collected
through extraction should be careful disposed off with other solid waste.

As highlighted in Module 3 – worker safety, all workers must be provided with PPE where any health
risks from air emissions are identified.

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4. SOLID WASTE
Minimum Standards Requirement
Confirm no breaches of consent limits in past 12 months
There must be no unauthorised burning of solid waste
Solid waste disposal must meet local authority requirements

Marks & Spencer suppliers should only send waste to disposal when all other safe opportunities for
recycling and reuse have been explored. Empty chemical drums and boxes can be reused, waste fabric
can be sold to textile waste processors, and solid waste from ETPs can in some areas be used as a
fertilizer. However, ETP sludge can contain dangerous chemicals and its use and disposal will be subject
to varying controls and permissions from the appropriate authorities must be sought before its use. If and
when solid waste has to be disposed of, it must be done in accordance with the local and national
regulations.

The calorific value of solid waste is relatively high and could be used as a fuel for boilers or heating
systems. However, the unauthorised burning of solid waste is not permitted by Marks & Spencer as solid
waste may release dangerous gases during burning that breach air consent and/or pollution regulations.
Permission from the appropriate authorities must be sought before solid waste is considered as a fuel
source.

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5. REDUCING WATER, ENERGY AND CHEMICAL

CONSUMPTION
Minimum Standards Requirement
Consumption of water, energy and chemicals is measured on an ongoing basis

There are many opportunities to reduce water, energy, chemicals and environmental impacts without
making fundamental changes to dyeing, laundry, tannery and printing processes.

5.1 Reducing water consumption

Minimum Standards Requirement

Water extraction does not exceed any local or national consent agreements

There is increasing global demand on fresh water supplies and Marks & Spencer has identified water as
the critical factor to tackle in reducing the impact of dyeing, printing, finishing of textiles and leather
production. In some areas of the world water supplies are very scarce and there are very strict limits on
the amount of water that factories can extract from rivers, lakes and boreholes. Every effort should be
made to minimise water consumption.

Two key tools for managing water consumption are the water meter and Right First Time (RFT)
processing.

Meters help identify the processes and activities that consume the largest amounts of water and where
the biggest saving can be achieved. Water meters should be installed to monitor the total site
consumption and wherever possible individual process and machine consumption.

Water meters: Essential for monitoring factory performance

Having high levels of RTF ensures that material is processed only once, and therefore, water
consumption is kept to a minimum. Poor quality control and low RFT results in materials being dyed two,
three or more times, resulting in a doubling or even tripling of water consumption. It is well proven that
water consumption can be dramatically reduced by instigating the best practice to improve RFT.

Other determining factors for controlling water usage are liquor ratio and the number of baths used in
processing. For batch processing liquor ratio can vary between 4:1 and 20:1 so for any given process the
amount of water used can vary by a factor of five. Using modern machinery and lower liquor ratios are
major tools for reducing water consumption. However at very low liquor ratios rinsing and washing
processes are not very effective so consider using fewer baths of longer liquor ratio for effective washing.
Over-flow rinsing to improve the effectiveness of a washing process uses a very high volume of fresh

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water and should be avoided. In continuous processing the use of counter-flow washing is strongly
recommended.

One obvious way of reducing net water consumption

is to explore the feasibility of water re-cycling.

In the best dyehouses water recycling can result in no

effluent discharge and approximately 90% re-use of
water. For example, rinse baths can be re-used,
cooling water can be recycled, as can steam
condensate. Investment in reverse osmosis and
evaporator equipment can prove to be effective tools
in reducing water consumption.
Reverse osmosis system

5.2 Reduction in Energy Consumption

Energy is expensive and contributes to the cost of production. Just as important, most energy needs are
met by burning fossil fuels which contribute to air pollution and climate change. Reducing energy
consumption will save money and help protect the local and the global environment. As with water
conservation, the key tools for minimising energy use are measurement and managing quality control.

Sub-metering to establish energy use throughout the factory will identify processing which consume the
most power and areas where energy efficiency can be improved. Good quality control will ensure products
are processed once with no need for re-processing and the associated energy use that goes with re-
dyeing, re-washing etc.

As with water, energy can be recycled by using heat

recovery systems, with up to 40% saving in energy use
being achieved in some areas. Heat can be recovered from
hot water, hot gases and even warm effluent. Heat recovery
systems on new machines and boilers, and even retro fitted
heat recovery systems can payback within 1 to 2 years. Also
some factories use as much water for cooling as they do in
process baths. Water consumption can be halved if cooling
water is recycled. Pumping clean, warm cooling water down
a drain is a significant waste of water and energy. Heat recovery system

Koenig are recognised specialists in the field of heat recovery:

http://www.luwa.com/SystemKoenig/WaterHeatRecoveryMain/WaterHeatRecovery

Wet processing machines use electricity and steam. It is obvious that the longer and hotter the process
the more electricity and steam that is used. To reduce energy consumption consider shorter or lower
temperature processes. Drying machines, steamers and ovens use fans and blowers that consume
electricity. An obvious way to reduce energy is to plan production so these machines can be switched off
when they are not actively processing materials.

A significant way to reduce electricity consumption is to use AC drives for pumps, blowers, and pulleys.
AC drives use approximately 20% less energy than DC drives and the payback can be less than one year.

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A further energy reduction of up to 20% can be achieved by insulating all machines that contain hot water.
All hot water pipes should be insulated to avoid heat losses and all leaks should be repaired to prevent
wastage of water.

One of the most important ways to improve efficiency is to check all steam pipes for leaks and all steam
traps for effective operation. Leaks from pipes and poorly functioning steam traps waste energy and
water.

5.3 Compressed Air

It is important to ensure air compressors are appropriate to the size of

demand. Oversized compressors are very inefficient and waste
considerable energy and money.

Compressed air systems should be checked on an ongoing basis and

all leaks repaired immediately. Use of compressed air should be
regularly assessed and poor practice should be avoided at all times.
For example, operatives should not use compressed air for cleaning
machines. Suction cleaning using vacuums is far more effective at
cleaning as well as using less energy.

Air compressor

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6. BEST PRACTICES FOR ECO-FACTORIES

Marks & Spencer has developed a set of best practice guidelines for factories of any type to reduce
energy and water consumption. These guidelines were a result of the Marks & Spencer sponsored eco-
factory projects in the UK and Sri Lanka. The most important aspects of the best practice guidelines are:

 Maximise the use of natural light

 Use energy efficient light bulbs
 Use PIR light switches in areas that are not frequently
used
 Insulate buildings to keep them cooler in summer and
warmer in winter
 Use natural ventilation and minimise use of air-
conditioning
 Preventative maintenance programmes to identify and
fix leaks
 Turn off machines and equipment when not in use
 Train workers in the need to conserve water and energy
Eco - factory
 Use of non return valves on steam and water pipes

In addition, to this learning, Marks & Spencer have recognised the work of NRDC in developing best
practice guidelines to reduce water and energy usage in textile wet processing mills. Implementation of
the NRDC best practice has been proved to reduce consumption of these vital resources, as well as
reduce operating costs for little or no capital investment. Where investment has been required the
payback period has been less than 12 months. The NRDC 10 Best Practices to Reduce Water and
Energy Use are listed below.

More information on the NDRC can be found at: http://www.nrdc.org/default_t.asp

6.1 Leak detection and preventive maintenance, improved cleaning

A single 2mm steam leak can result in the loss of energy equal to more than 10 tons of coal. Experts
estimate that textile facilities can reduce water and energy use by as much as 10% through effective leak
detection and preventative maintenance programs. It has been estimated that water and steam leaks
were responsible for between 1-5% of all water and coal usage. Larger savings can be expected from
improved water conservation such as turning off hoses when they are not being actively used.

6.2 Reuse of non-contact cooling water

Non-contact cooling water is high in quality and temperature and can be easily reused for other
processes. In addition, non-contact cooling water’s high discharge temperature (45°C) and volume adds
unnecessary load to effluent treatment plants.

Install a water reuse and heat exchanger system can help make use of this water and energy resource
leading to savings across the business.

6.3 Reuse of steam condensate

Textile mills rely on a large amount of saturated steam some of which will condensate into very high in
temperature water of a very pure nature. The most efficient use of this condensate is to return it to the

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boiler for conversion back into new steam. Even for sites which do not have their own boiler the
condensate can serve as a water supply for washing or desizing. Installing pipes to capture and reuse
condensate can help saving a substantial amount of energy and water.

6.4 Reuse water from pre-treatment processes

Instead of discharging water from bleaching and mercerizing machines to the effluent treatment plant it
can be collected and reused for other processes. After simple treatment for removal of fibrous matter, this
water usually meets the quality requirements for scouring.

6.5 Recover heat from hot rinse water

During manufacturing, large quantities of very hot water are used for rinsing. The heat from this rinse
water can be captured and used to preheat the incoming water for the next rinse. A plate heat exchanger
can transfer wastewater heat energy to incoming cold freshwater. This opportunity can incur a high initial
cost, but in all instances the investment pays back quickly, within two and four months.

6.6 Pre-screen coal

In mills using coal fired boilers the adoption of spiral coal screen technology can increase the efficiency of
the fuel by separating good quality, high calorific coal from low quality coal.

6.7 Maintain steam traps

Steam traps play an important role in maintaining the efficient flow of steam through a mill by removing
moisture and preventing condensation. Therefore, they reduce heat loss and so reduce overall fuel
consumption. However, poorly maintained steam traps will allow live steam to escape into the condensate
system and so increase heat loss and fuel consumption. In steam systems that have not been adequately
maintained, between 15% and 30% of the traps may have failed.

Regular inspection of steam traps (monthly testing is recommended) and repair or replacement of broken
traps will reduce loading on the boiler and save money. In addition, steam traps should be installed at
appropriate intervals (typically one about every 25 meters) from the main steam headers for most effective
use.

6.8 Insulate pipes, valves, and flanges

Heat loss from pipes, valves, and flanges will waste energy and therefore money. Insulating steam pipes
is inexpensive and will save money. According to industry data, one meter of un-insulated steam pipe
could lose the equivalent energy of nearly three tons of coal per year.

If all steam pipelines, flanges and valves in a typical factory are well insulated, heat loss from steam pipes
could be reduced by up to 90%. Routine inspection of pipe, valve, and flange insulation throughout the
mill well ensure on going energy and cost savings

6.9 Recover heat from smokestacks

A boiler can produce smoke fumes at a temperature of 360°C. Often these fumes and the energy they
carry are directly discharged into the atmosphere. Installing a waste heat boiler to use this heat can help
2
reduce energy consumption, CO emissions and costs. The waste heat boiler can be used to pre-heat the
main boiler feed water or as a supplementary steam supply for the mill.

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6.10 Electricity Saving from Compressed Air

Large amounts of compressed air are used through-out a mill for a wide range of processes. Every air line
is susceptible to leakage, which can account for 20 to 75 percent of air demand in a plant where no
regular maintenance is carried out. Compressed air leaks most commonly exist at threaded connection
points, rubber hose connections, valves, regulators, seals, and old pneumatic equipment.

In addition, the working pressure of compressed air is often set according to the maximum pressure
required by the mill. It is often possible to reduce this pressure without any negative impacts on
manufacturing, which will save energy as well as reduce the volume of air loss through any remaining
leaks.

Optimizing the compressed air system could save between 2 and 59 kWh per ton of production, or
between 0.3%t and 3% of its total electricity use.

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