The textile industry is one of the complicated and vast industries with many processes and hence for this process, there is a need for sufficient energy. Energy is one of the main cost factors in these industries. Especially in times of high energy price increase per unit, improving energy efficiency opportunities that exist in every textile plant. Economic use of electric power is gaining more importance.
Hence in power cuts own generators are used. Cost of own generators is 2-2.5 times more than that of power supplied by utilities. Power consumption in textile industry is controlled by modification in machine parts, driving system, by using energy efficient motors and should have maintenance practice. The energy cost is around 15 % to 20 % and more.
The production cost and it stands next to raw material cost. Hence now a day’s area of focus is towards energy consumption at load end and by optimizing the efficiency of the motor. In this paper, the influence of energy-saving motors and process of Optimization in the textile mill on energy conservation is discussed with practical data.
In the textile industry, electricity consumption and power cost are increasing trend due to using modern machines and continues the range of machines by efficient operating parameters. The main objective of the textile mill is to produce yarn from the raw cotton which requires six stages of the process.
These are discussed briefly as follows. The textile mill can be split into three systems namely, card sliver, combed sliver and ring spinning system. The card sliver system consists of blow-room and carding machine, which does the function of removing the foreign particle from the raw cotton and convert the same into thick yarn.
The combed sliver system consists of draw frame and Comber machines, the draw frame machine ensures the uniformity in thickness of the sliver and comber machine removes the unwanted short fiber in the sliver. Ring spinning system consists of Speed frame and Ring-frame machine, which does the conversion of sliver into yarn. Ring frame produces a final product of the spinning mill.
Power Consumption In Textile Industry
The power required to drive the spinning frame increases as the cube of the speed. Production per unit power decreases to one half and one quarter as the speed increases from low to high rpm. Here a data is collected on power consumption in the composite mill.
|Department||Power Consumption %|
Power consumption in spinning department
|Post comb drawing||0.8|
The table shows that ring-frame consumes almost 80% of the power required for the entire spinning department.
The break-up of power consumption of ring-frame is given below
Major Areas Of Power Saving In Ring-Frame
- Optimization of motor H.P
Choice of the motor of the right type and H.P is done when consumption of energy comes. Too high H.P motors lead to under loading of the motor and higher power consumption.
To control end breaks and roller lapping’s speed is reduced. At that time lower H.P motors should be used. The dual motor drive is necessary. By using correct H.P motor 20% power saving is done. The motor should be loaded up to 85%.
- Proper choice of spindle drive wharves
Drive to tin roller and spindles leads to more power consumption hence 20% savings are done in 22mm wharve diameter as compared to 25mm. By reducing tin roller speed for 22mm wharve diameter no any slippage of the belt occurs.
- Use of narrow width spindles tapes
Wider width tape consumes more power because of greater bending resistance and winding losses.
16 mm tape: 6-7% more power consumption as compared to 13mm.
13 mm tape: Less slippage, and low power consumption.
- Use of Nylon tapes (sandwich) spindle tapes
By using such tapes 8-10% reduction in power consumption. P/c woven tapes are also used.
- Adoption of flat drive to ring frame
Ring frame is driven by V belts. From this point of view power consumption of V belt had the disadvantage that an immersive loss of energy taken in wedging and pulling out the belts from the V grooves during each revolution as shown in above figure. V belt offers considerable bending resistance. Flat belt is free from bending resistance and good grip and consumes less power consumption up to 6-8%.
- Proper choice of front roller speed
Power consumption is not affected by an increase in front roller speed to increase production. Production can be increased by reducing the spindle speed and twist multiplier. This is possible in fine counts where TM used is more.
- Optimization of oil level in bolster
Power consumption goes on increasing with increase in oil level in bolster because of resistance offered by the oil. At the time of topping oil waste occurs due to full oil in bolster and more power consumption takes place. Hence oil level should be 4.5 ccs.
Power Savings In Humidification Plant
The humidification motors should be optimized for its H.P depending on the load. Root cleaning should be done during the summer month. Exhausting of pneumatic air outside the department and false ceiling to reduce the conditioned space are some measures to reduce power for humidification.
- Refrigeration capacity reduced by 6% for every 3.5-degree increase in condensing temperature.
- Reducing condensing temperature by 5.5-degree results in a 20%-25% decrease in compressor power consumption.
- A reduction of 0.55 degree in cooling water temperature at condenser inlet, reduces compressor power consumption is 3%.
- 1mm scale build-up on condenser tubes can increase energy consumption by 40%.
- 5-degree increase in evaporator temperature reduces compressor power consumption by 20%-25%.
Compressed Air Used In Departments
- Every 5°c reduction in intake air temperature would result in 1% reduction in compressed power consumption.
- Compressed air leak from 1mm hole size at 7kg/cm pressure would mean power loss equivalent to 0.5kw.
- Reduction of 1kg/cm air pressure would result in 9% input power saving.
- For a reduction in 1kg/cm line pressure the leakage quality from 1mm size hole reduced by 10%.
Lightning In Department
- Replacement of incandescent bulbs by CFL’s offer 75%-80% energy savings.
- Replacement of conventional tube lights by new energy efficient tube light along with electronic ballast help to reduce 40%-50% of power consumption.
- 10% increase in supply voltage will reduce bulb life by 1/3 rd.
- 10% increase in supply voltage will increase lighting power consumption by an equivalent 10%.
- Use electronic ballast.
- Use reflectors whenever possible.
- Apply maximum glass windows while construction.
- Clean tubes frequently once/week.
These are small modifications or alteration of the energy use facilities may result in energy conservation to a large extent.
In India, there are many textile industries. Hence, by incorporating the above technique in all the textile mills, ample energy can be saved. In general, most of the mills have not included renewable energy techniques in productive and non-productive machines. By means of adopting these techniques, significant energy saving can be realized.