Supported by

EIE/04/246/S07.38678

 

 

 

 

Benchmarking and Energy management Schemes in SMEs

 

Measure List Textile Industry

(scroll down for a more comprehensive description)

 

To download this list in Excel format click here

 

Process-related Improvement Opportunities

 

 

Energy Efficiency Method

 Short  Description/ procedure stage

1.      Replace rinsing baths with jets

Dyeing: Achieve to use lower quantities of liquid, less heating and cooling.

2.      Use vacuum extraction before washing and/or drying

Drying/washing: This quite new technique is used to extract as much water from the fabric

3.      Modify burners in stretchers, dryers and singeing machines

Adjustment or replacement can result in energy saving.

4.      Increase drying capacity with IR, NIR, HF and RF (radio frequencies)

Drying: Use radio frequencies to increase the capacity of stretchers and for preliminary drying.

5.      Use ultrasonic techniques for washing or dyeing textiles

Drying: Use ultrasonic waves to improve bath washing and dyeing process.

6.      Utilise modern, energy-efficient spinning, knitting and weaving equipment

Energy saving methods over all stages of productivity

7.      Prevent air intake in the steamer

Dyeing: Keep the splits in steamer as small as possible to reduce the steam consumption

8.      Replace oil-fuelled equipment with gas-fuelled models

Increase the participation of gas-fuelled plants because of its energy efficient characteristics

9.      Utilise ink-jet printing technology

This trend in the textile sector is used particularly for shorter rung lengths

10.  Automate water intake in dyeing equipment

Accomplishment of significant water saving

11.  Place washer’s wash tubs in counter-flow

Accomplishment of significant water saving

12.  Optimize the use of basic materials and additives

Reduction of consumption of basic materials

 

13.  Change to new, more advanced fibres.

New fibers are subjected to less treatment due to product characteristics

14.  Use bio-gas from waste water purification

The bio-gas from waste water can generate heat used in the productivity cycle.

15.  Utilise targeted extraction

Utilize local extractor hood

16.  Minimize rejects by purchasing high quality basic material

Energy conservation method

17.  Minimize rejects by improving composition control

Energy conservation method

18.  Reduce the liquid ratio in discontinuous equipment by means of suppression elements and/or by optimising piling

Dyeing: Energy conservation method to reduce water and energy amounts.

19.  Increase fabric speed in wide washer

Optimize fabric speed while keeping the washing results

20.  Optimise temperature setting on wide washer

Software material can be used for these purposes

21.  Reduce chemical doses in the wide washer

Software material can be used for these purposes

22.  Modify rinse ratio in wide washer to between 1:3 and 1:5

Optimize the wide washing process

23.  Monitor the rinsing process during washing using sensors (including conductivity meters)

Monitor the process can result in time, water and energy savings

24.  Control extractor air based on moisture content and/or underpressure in stretcher or dryer

Drying: Limit the amount of extracted air, by measuring the moisture content.

25.  Control temperature setting in stretcher and dryer with a pyrometer

Drying: Install pyrometer to measure the temperature of the fabric- attire significant information on the over-drying

26.  Use wet-in-wet treatment

Drying: Wet-in-wet treatment means integrating two sub-processes, making the intermediate drying stage redundant

27.  Ensure proper steam conditioning in the steamers

An important method in order to avoid a detrimental effect on the temperature and moisture content of the fabric

28.  Optimise the rotation speed of spinners, twisters and rinsers

It is proven that equipment is more energy consumption at high speed

29.  Take measures to reduce rejection and over-processing

Do necessary adjustments to optimize the procedure in total

30.  Optimise computer program for equipment control

Use specific software material to monitor the operation of the equipment

31.  Control the liquid level in discontinuous dyeing processes

 

Energy conservation method

32.  Measure the moisture content of fabric in drying processes

 

Drying: Measure the fabric moisture to adjust the machine operation

33.  Reduce air extracted from stretchers by means of valve settings in extraction channels

 

Adjust the valves to regulate the quantity of air

34.  Reduce dyeing periods by measurement and control (including pH and conductivity)

 

Dyeing: By using pH meters, adjust time periods of dyeing

35.  Reduce temperature of rinsing water

 

Energy saving method

36.  Use dyes with a higher fixation degree

 

The fixated dyes need less energy and water than the non-fixated ones

37.  Installation of control unit

Batch dyeing: Install control units to monitor the batch dyeing procedure

38.  Hot water consumption reduction in jigger

Batch dyeing: In the jigger is measured an significant energy conservation

39.  Usage of vacuum dewatering systems

Batch dyeing: Very significant water conservation - recommended mechanical systems

40.  Avoid over-temperature over open dyeing machines

Batch dyeing: Recommended temperature for a safer operation is 950

41.  Usage of MA techniques

MA (Minimum Application) techniques share the characteristic of applying less moisture to the fabric

42.  Prefer closed machines

Thermal loss reduction

43.  Usage of low add-on liquor application systems/reduction of volume capacity

Energy saving method

44.  Adoption of dispensive systems

Adopting dispensing systems where the chemicals are dispensed on-line

45.  Avoid washing at temperatures >950 in open/semi-closed machines

Avoid washing at temperatures of 95 °C or more when the washing tanks aren’t perfectly closed.

46.  Adaptation of water flows

Increased productivity method

47.  Use mechanical drying

Drastic moisture reduction prior to thermal drying

48.  Control Steamers

Monitor steam extraction

49.  Minimise energy consumption in stenter frames

Drying: Reduce water content of the incoming fabric

50.  Minimise energy consumption in stenter frames

Maintaining exhaust-humidity between 0.1 and 0.15 kg water/kg dry air

51.  Minimise energy consumption in stenter frames

Install heat recovery systems

52.  Minimise energy consumption in stenter frames

Fit insulating systems

53.  Minimize energy consumption in stenter frames

Ensure optimal maintenance of the burners

54.  Reuse heat of discharge from stretchers and dryers

Recycling of heat- used not in large scale.

55.  Reclaim residual heat from the dyeing and washing equipment

Use a heat exchanger and collect the heat in order to reuse in the washing phase.

56.  Avoid overflowing conditions

Batch dyeing: Energy saving method.

 

 

Full description method

 

 

  1. Replace rinsing baths with jets: By replacing rinsing baths with jet paint equipment, the liquid ratio can be drastically improved. This means that lower quantities of liquid will require heating and cooling. Depending on the bath and jet models, significant reductions can be achieved in the steam and/or gas consumption.
  2. Use vacuum extraction before washing and/or drying: Vacuum technology is now a proven savings option in drying and washing processes in particular. After treatment, by running wet fabric over a vacuum beam, much water can be extracted from the fabric.  As a result, less energy is required to subsequently dry the fabric. This technique is particularly suitable for fabrics made of artificial fibres, such as polyester. It is less suitable for cotton as yet because fuzz and dirt can leave deposits behind. Vacuum extraction can also be used in support of the washing process.
  3. Modify burners in stretchers, dryers and singeing machines: The burners in stretchers, dryers and singeing machines must be optimally adjusted to suit their purpose. Burners with oversized dimensions and limited yield have or can cause incomplete combustion. Adjustment or replacement can result in energy savings.
  4. Increase drying capacity with IR, NIR, HF and RF (radio frequencies): Alternative methods for drying textiles that are now being used include IR (Infra-Red) drying in particular. IR drying uses ceramic radiators installed above the fabric line in one or more elements. These units are either gas fuelled or use electricity. These techniques have been improved in recent years; the elements can be rapidly switched on and off to avoid fabric fires when the fabric is not moving. In particular, this technique is used to increase the capacity of stretchers and for preliminary drying.
  5. Use ultrasonic techniques for washing or dyeing textiles: Ultrasonic waves can accelerate and improve bath washing and dyeing processes. Mechanical washing is still needed. The processing period can be reduced using this technique. As a result, the washer model can also be compacter and less expensive.
  6. Utilise modern, energy-efficient spinning, knitting and weaving equipment: The mechanical processes in the textiles industry – spinning, weaving and knitting – have experienced important developments. Modern spinning equipment, for example, use light-weight spindles that are powered separately. This reduces energy consumption. The production speed of weaving equipment has increased significantly, including by means of improved grab lines, and especially by the introduction of air weaving systems. These make production more energy efficient. For the record, part of this effect is negated with air weaving systems due to the energy used to generate the necessary compressed air.
  7. Prevent air intake in the steamer: In the steaming process, constant and reproducible conditions must be achieved in the steamer atmosphere. A disruptive factor can be the intake of air in the steamer, for example via the enter and exit splits. This air reduces the temperature in the steamer and makes the atmosphere unstable. In some processes, oxygen disrupts the chemical reactions important for fixating dyes. As a result of these disruptions, more steam than necessary is added to establish the desired conditions as yet. Keeping the splits in the steamer as small as possible can reduce the steam consumption.
  8. Replace oil-fuelled equipment with gas-fuelled models: Heating up machines by means of thermal oil is energetically inefficient due to the fact that electricity is used and because of losses during the generation, storage and transport of the heated oil. Where possible, the use of directly gas-fuelled equipment is strongly recommended.
  9. Utilise ink-jet printing technology: This development addresses the trend towards increasingly shorter rung lengths and batches. Conventional silk-screen techniques are only efficient and profitable for batches of at least 3000 metres. Extremely short lengths can be produced efficiently and flexibly using ink-jet printing or xerography. Unlike with silk-screening, these techniques do not leave residual baths and their waste percentage is significantly lower. Textiles printers can use these techniques to address the demands for Quick Response and flexibility, enabling them to quickly attune to changing trends and fashion-sensitive applications. Ink-jet technology is already being used in the Netherlands on a modest scale, in particular for the production of short lengths and specialities.
  10. Automate water intake in dyeing equipment: By automating the water intake in dyeing equipment, taps are not left open unnecessarily long. Automation, however, requires an accurate understanding of the water demand during the process. Significant reductions in water consumption have been achieved using this method, often conserving large amounts of energy.
  11. Place washer’s was tubs in counter-flow: In important principle in continuous washing processes is utilising the counter-flow in the water intake. This reduces water and energy consumption while improving the washing results.
  12. Reduce the use of basic materials and additives: This measure contributes to indirect energy savings with reference to the energy used to manufacture these materials.
  13. Utilise the characteristic of new fibres: Using new fibres can generate important product innovations. This may also reduce energy consumption because a number of fibre types are easier to process.
  14. Use bio-gas from waste water purification: The bio-gas generated by certain types of waste water purification can be used to produce heat. Consider, however, that this measure involves additional costs for the H2S purification.
  15. Utilise targeted extraction: Targeted extraction can be used, for example, by using local extractor hoods for the process baths. As a result, the thermal path of the heated and moist vapour from the process baths can be optimally utilised. The ventilation debit in the hall in which the baths are located can also be reduced. In addition to energy savings, this reduces the erosion to the building caused by the moist air. Savings in the energy consumption for ventilation and heating/cooling.
  16. Limit rejects by improving basic material purchasing: The quality of the basic materials is one of the factors that determine the quality of the finished product. Improved purchasing will limit the level of rejection and conserve energy.
  17. Limit rejects by improving composition control: Improved control of the composition of the material will limit rejection and conserve energy.
  18. Reduce the liquid ratio in discontinuous equipment by means of suppression elements and/or by optimising piling: The liquid ratio in discontinuous equipment can be reduced using elements that fill spaces normally occupied by threads or fabric, but when the load is incomplete these only increase the bath volume. Machines can also be modified by adding permanent fixtures that reduce the bath volume. However, the liquid must continue to flow properly to safeguard the correct thread or fabric flow. Furthermore, cone piling can be optimised, e.g. by using cones of a different shape or rolls. Measures like these, reduce water and energy consumption.
  19. Increase fabric speed in wide washer: Optimising the wide washing process can be done using measures that include increasing the fabric speed while maintaining the washing results. In order to do so, the washer must be mapped in detail and the relevant process parameters measured if necessary. Software can be used to identify the various options.
  20. Optimise temperature setting on wide washer: Optimising the wide washing process can be achieved using measures that include attuning the temperatures of the various tubs while maintaining the washing results. In order to do so, the washer must be mapped in detail and the relevant process parameters measured if necessary. Software can be used to identify the various options.
  21. Reduce chemical doses in the wide washer: Optimising the wide washing process can be done using measures that include reducing the chemical doses while maintaining the washing results. In order to do so, the washer must be mapped in detail and the relevant process parameters measured if necessary. Software can be used to identify the various options.
  22. Modify rinse ratio in wide washer to between 1:3 and 1:5: Optimising the wide washing process can be done using measures that include setting the proper rinse ration while maintaining the washing results. In order to do so, the washer must be mapped in detail and the relevant process parameters measured if necessary. Practical and theoretical considerations indicate that a ratio between 1:3 and 1:5 will generally render the best results. Software can be used to identify the various options.
  23. Monitor the rinsing process during washing using sensors (including conductivity meters): Measuring the wash parameters during the process can result in time and water, and therefore energy, savings. The temperature and the conductivity of the bath in particular are important indicators for the washing results.
  24. Control extractor air based on moisture content and/or underpressure in stretcher or dryer: The air extracted from stretcher and dryers can contain a maximum amount of water vapour. By measuring this moisture content, the quantity of extractor air can be limited if the moisture content is below the maximum. As a result, less air needs heating and energy is conserved. Important in this measure is maintaining the underpressure in the machine, to avoid ‘smoking’ risks.
  25. Control temperature setting in stretcher and dryer with a pyrometer: Contact-free temperature sensors, known as pyrometers, can be placed at one or more points along the fabric line to measure the temperature. This generates important information about the course of the drying process. It makes it possible to optimally adjust the temperature of the various stretcher fields while preventing over-drying.
  26. Use wet-in-wet treatment: Wet-in-wet treatment means integrating two sub-processes, making the intermediate drying stage redundant. By adding a limited amount of moisture (with chemicals) in the first stage, sufficient absorption capacity remains in the fabric to go straight to the next treatment stage. Removing the drying stage can save huge quantities of energy. Adding moisture in a wet-in-wet process is done using one or more MA techniques.
  27. Ensure proper steam conditioning in the steamers: The proper steam conditioning is important. Most processes use saturated steam. Make sure the steam is not overly heated: this has a detrimental effect on the temperature and moisture content of the fabric. Sub-optimal steam conditions will generally result increased steam consumption.
  28. Optimise the rotation speed of spinners, twisters and rinsers: Spinners, twisters and rinsers have proven to consume relatively more energy at higher rotation speeds. It must be determined whether the increased production justifies this increased consumption with a view to the desired production and logistics attuning (waiting periods for subsequent processes).
  29. Take measures to reduce rejection and over-processing: Over-processing material and rejections can be reduced by optimising the processes. The reproducibility of the process is determinant in this respect. In most cases, this can only be achieved by thoroughly measuring the process parameters and making any necessary adjustments. Various methods are available for determining causes for the need for over-processing. Naturally, reducing over-processing and rejection will bring significant energy savings, both directly and indirectly (basic materials).
  30. Optimise computer program for equipment control: The software for controlling equipment, especially dyeing equipment, should be periodically evaluated to determine whether they provide optimal control for the relevant process. Over the course of time, smaller and larger process modifications may have taken place, or different chemicals may be used. As a result, it may be possible to reduce dyeing periods in some cases, resulting in energy savings.
  31. Control the liquid level in discontinuous dyeing processes: Adjusting the liquid level in discontinuous dyeing processes can save water and therefore conserve energy. Moreover the reproducibility of the process will be improved.
  32. Measure the moisture content of fabric in drying processes: Measuring the fabric moisture content makes it possible to adjust the machine based on residual moisture content. Savings can be achieved by increasing the machine speed and/or reducing the quantity of discharged air.
  33. Reduce air extracted from stretchers by means of valve settings in extraction channels: The quantity of air extracted from a stretcher can be easily adjusted by adjusting the valves (manually). It may be possible to automatically adjust the valves, depending on the process operations.
  34. Reduce dyeing periods by measurement and control (including pH and conductivity): Measuring the dyeing parameters can result in savings because this makes it possible to determine when the dyeing process has been completed.
  35. Use dyes with a higher fixation degree: The manufacturers of dyes and chemical additives are continually improving their products. By changing recipes, processes can be modified, shortened and made more energy-efficient. In particular, improving the fixation yield contributes to this because less energy and water are needed to rinse non-fixated dyes from the fabric.
  36. Install automatic controllers for control of fill volume and liquor temperature in batch machines: Use machinery fitted with automatic controllers of fill volume, temperature and other dyeing cycle parameters.
  37. Fit hoods and covers ensuring full closure of machinery that could give rise to vapour losses
  38. In the jigger, rinsing in batches can reduce hot water consumption by between 30 – 60%.
  39. If possible use vacuum dewatering built into a jigger. This results in water savings of more than 80% and consequent savings in energy consumption. Install mechanical dewatering if possible.
  40. Don't use open dyeing machines at temperatures higher than 95°C
  41. Minimise residual liquor by using minimal application techniques (e.g. foam application, spraying) or reducing volume of padding devices
  42. Prefer washing machines that are as much as possible closed (the tanks themselves and between the tanks).
  43. Using low add-on liquor application systems and minimising volume capacity of the dip trough when using pad dyeing techniques
  44. Adopting dispensing systems where the chemicals are dispensed on-line as separate streams, being mixed only immediately before being fed to the applicator
  45. Avoid washing at temperatures of 95 °C or more when the washing tanks aren’t perfectly closed.
  46. Adapt water flows to the production
  47. Squeeze off the textile material between and possibly also in the washing tanks
  48. Control steamers so that not to much steam is extracted
  49. Minimise energy consumption in stenter frames by using mechanical dewatering equipment to reduce water content of the incoming fabric
  50. Minimise energy consumption in stenter frames by optimising exhaust airflow through the oven, automatically maintaining exhaust-humidity between 0.1 and 0.15 kg water/kg dry air.
  51. Minimise energy consumption in stenter frames by installing heat recovery systems.
  52. Minimise energy consumption in stenter frames by fitting insulating systems
  53. Minimise energy consumption in stenter frames by ensuring optimal maintenance of the burners in directly heated stenters
  54. Reuse heat of discharge from stretchers and dryers: The heat discharged by stretchers and dryers can be recycled using heat exchangers. These are not yet used on a large scale, primarily because it is believed that this will cause difficulties in machine maintenance and accessibility.
  55. Reclaim residual heat from the dyeing and washing equipment (using a heat exchanger): The heat in the discharged process water from dyeing or wide washing equipment can be reclaimed with a heat exchanger and reused in the washing process. Depending on the process and the machine dimensions, this can render large savings.
  56. Unsuitable rinsing conditions such as overflowing should be avoided. Either for waste water and energy matters or to avoid mal operation of machines. 
  57. Energy audits: Energy audits are recommended since they cover all units like power and steam consumption, all A/C plants, lighting and motor studies, water consumption, all process stags.

 

 

                     

Note 1 The sole responsibility for the content of this publication lies with the authors. It does not represent the opinion of the Community.Β  The European Commission is not responsible for any use that may be made of the information contained therein.