Process Flow Chart Of Water Treatment Plant (WTP) || WTP For Textile Industry

Water treatment plant (WTP) is necessary for every wet processing industry. In case of textile wet processing; water is required for dyeing, printing, finishing as well as garment washing. We know water is two types; hard water and soft water. The water which is collected from up of the soil or under the soil it may contains different chemical substances which makes the water hard. That hard water is not suitable for the wet processing. For this reason, it is required to purify the hard water. After purification by the water treatment plant, water becomes ready for the next wet process.



Process Flow Chart of Water Treatment Plant (WTP): The flow chart for water treatment plant is given below.

Hard Water Store Tank

↓

Stone Filter

↓

Carbon Filter

↓

Resin Filter

↓

Soft Water Store Tank

↓

Delivery Pump

Water Softening: There is an ion exchange method by which hardness of water is removed. After removing the hardness, water becomes soft and following parameters are maintained for considering a soft water. Here, I have present the standard for soft water.

Standard Water Quality for Dye House:

Parameter	Permissible concentration
Color	Color less
Smell	No bad smell
Water Hardness	<5 ppm
PH value	7-8 (Neutral)
Dissolve solid	< 1 ppm
Inorganic salt	< 500 ppm
Iron(Fe)	< 0.1 ppm
Manganese(Mn)	< 0.01 ppm
Copper (Cu)	<0.005 ppm
Nitrate(NO3)	< 50 ppm
Nitrate(NO2)	< 5 ppm

So, before processing, a textile engineer should ensure the quality of soft water.

Water Hardness | Effect Of Hard Water In Textile Industry

Water is the main running substances for wet processing of the textile industry as well as other manufacturing industry. The water which is in the environment that contains lots of impurities which required to purifying before use. By the purification, natural water becomes suitable for process.

Water for a textile plant may come from various sources. These include surface water from rivers and lakes, and subterranean water from wells. In most of the textile industries, they collect water from Underground. Natural and pretreated water may contain a variety of chemical species that can influence textile wet processing in general, and dyeing in particular.

The various salts present in water depend on the geological formations through which the water has flowed. These salts are mainly the carbonates (CO₃^2-), hydrogen carbonates or bi-carbonates (HCO^3-), Sulphates (SO₄^2-) and chlorides (Cl^-) of calcium (Ca²⁺), magnesium (Mg²⁺). Although calcium and magnesium carbonates in limestone are relatively insoluble in water. So in this reasons, water hardness can be divided into two ways. They are-

1. Temporary Hardness:  Ca(HCO₃)₂ , Mg(HCO₃)₂ , Fe(HCO₃)_2.

2. Permanent Hardness:  CaCl₂, CaSO₄, Ca (NO₃)₂, MgCl₂, MgSO_4, Mg (NO₃)_2.

Effect of Hard Water in Textile Industry: This water hardness causes some serious consequences in a textile dyeing and finishing industries and these are

• Precipitation of soaps.


• Redeposit ion of dirt and insoluble soaps on the yarn or fabrics being washed, this can cause yellowing and lead to uneven dyeing and poor handle.


• Precipitation of some dyes as calcium and magnesium salts.


• Scale formation on equipment and in boilers and pipelines.


• Incompatibility with chemicals in finishing recipes and so on.

Hardness expressed by parts per million (ppm) of CaCO₃ which is standard hardness scale and it is also called American hardness. The hardness of raw water is 100 ppm or more. To use it in dyeing and in boiler this water must need to soft & foreign materials needs to remove.

Organ Gram Of Dyeing And Finishing Textile Industry

Dyeing and finishing are the combined section of textile industry. This dyeing and finishing industry could be based on Yarn, Knitted or Woven fabrics. Generally, finishing is done after dyeing process. After finishing, materials are sending to garments or printing section for further operation. In every organization there have a managerial system which control the whole process. There have various sections in an industry. Every section is related to the production and its assistance.

Organ gram Of Dyeing and Finishing Textile Industry: The dyeing and finishing textile industry is run by the following managerial system.

Chairman

↓

Managing Director (MD)

↓

Executive Director (ED)

↓

Director (Production/ Finance)

↓

General Manager (GM)

↓

Deputy General Manager (DGM)

↓

Assistant General Manager (AGM)

↓

Manager (Dyeing/Finishing)

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Assistant Manager (Dyeing/Finishing)

↓

Senior Production Officer (SPO)

↓

Production Officer (PO)

↓

Assistant Production Officer (APO)

↓

Dyeing Master

↓

Shift In – Charge

↓

Floor In – Charge

↓

Supervisor

↓

Operator

↓

Helper

Above managerial system is must for better management. But it is very rear because all of the industries are not same in volume and not interested to main all of the class of the managerial system. For this reason, some part of the managerial system could be absent.

So, if anyone wants to get better production he or she should have to maintain the above managerial system.

Dyeing & Printing || Differences Between Dyeing And Printing

Dyeing and printing are the two major wet processing techniques for coloration of fabric. In the dyeing process; only one color is produced but in the printing process; various types of colored design are produced on the fabric surface. Dyeing is done on grey fabric but printing could be done on both pre-treated fabric and colored fabric.

Difference Between Dyeing And Printing: There is a lot of difference between dyeing and printing process. Here, I have mentioned some major difference between dyeing and printing.

Dyeing	Printing
1. By the dyeing process, dyes are applied on the whole fabric equally.	1. By the printing process, dyes are applied on the fabric localizedly to produce desired design.
2. Fabric, yarn and fibers are dyed by dyeing.	2. Generally printing is done on fabric.
3. In a dyeing process, dyes are applied on the both sides of the fabric.	3. Dyes are applied on olnly one side of the fabric.
4. No precise design is required for dyeing.	4. Design is must for printing.
5. In a dyeing process, only one dye is used.	5. In a printing process, one or more dye is used.
6. Precise temperature is required for dyeing.	6. In printing, it is not necessary to maintain precise temperature.
7. Thickener is not required for dyeing.	7. Thickener is must for printing paste preparation.
8. The density of dye solution is less than the density of printing paste.	8. In printing, the density of printing paste is higher than dye solution density.
9. Huge amount of water is required for dyeing.	9. Small amount of water is required for printing.
10. Steaming or curing is not necessary for dyeing.	10. Steaming or curing is must for printing to fix the dyes or pigments on the surface of the fabric.
11. Dyeing is comparatively cheaper than printing.	11. Printing is costly than dyeing.
12. Dyed fabrics are soft.	12. Printed fabrics are hard and harsh.

Process Sequence Of Removal Softener Spots From The Dyed Fabric

Removal of softener spot from the Fabric is a washing process, which is done in the dyeing bath. Softener spot is a dyeing fault which is occurred during the application of softener to the fabric in dyeing bath or de-watering machine. When this type of fault is found in a dyed fabric then it needs to make free the dyed fabric from the softener spots.



Generally, acid wash is done for removing softener spot from the fabric. It is an off line quality assurance system. When this type of fabric faults found in the finishing section then it sends for acid wash in the dyeing section. By the following way, softener spot can be removed from the dyed fabrics.

Dyed fabrics are supplied to the dyeing section

↓

Required amount of water filled

↓

Fabric was loaded and run for 10 min.

↓

Drain

↓

Required amount of water filled

↓

Acetic acid was added for 5 min.

↓

Wetting agent added for 5 min.

↓

Run for 10 min. at 70⁰ C

↓

Rinse for 15 min.

↓

Drain

↓

Required amount of water filled

↓

Acetic acid added for P^H- controlled

↓

Check P^H at 4.5

↓

Enzyme added

↓

Run for 1 hrs

↓

Shade check

↓

Rinsing for 10 min.

↓

Anti-crease was added for 5 min.

↓

Leveling agent added for 5 min.

↓

Run for 20 min at 80⁰ C

↓

Rinsing for 10 min.

↓

Acetic acid added for P^H- controlled

↓

Check P^H at 6.5

↓

Softening agent injected

↓

Run for 10 min. at 50⁰ C

↓

Unload the Fabric

Quality control department of the industry should be aware about the dyeing faults and give proper decision to remove the faults.

Process Flow Chart Of Stripping In Dyeing | Cotton Knit Fabric Re-Process

Knit Dyeing is a critical procedure and it is required to match the shade of the dyed fabric with the buyer’s approved swatch. Sometimes, it is found that the dyed fabric shade does not match with the approved swatch then this fabric is required to re dyeing. This re dyeing process is called stripping. Most of the time, black shade or deep shade is produced by the stripping process. Topping is another re dyeing process but stripping and topping is use for different case.

Stripping sequence of knit cotton fabric: Reactive dyes dyeing process is done for cotton or cellulosic fiber. Here, I have given a stripping process for the cotton fabric.

Fabric received from the batching section

↓

Required amount of water was taken into the machine

↓

The fabric was loaded and run for 5-10 minutes in normal temperature

↓

 Wetting agent, anticreasing agent were added at a time for 5 minutes

↓

Caustic was dosing at normal temperature for 5 minutes

↓

Run for 10 min.

↓

Temperature increase at 110⁰C and continue for 40 min.

↓

Cooling at 80⁰C

↓

Hydrose inject for 5 min.

↓

Temperature increased at 110⁰C for 10 min.

↓

Run for 30 min.

↓

Cooling at 80⁰C

↓

Sample check

↓

Rinsing for 15 min.

↓

Hot wash

↓

Cold Wash

↓

Unload the Fabric

Stripping is done on the dyed fabric for this reason this type of re-dyeing increases the cost of the dyeing process.

Process Sequence Of Topping For Cotton fabric | Dyes Adding Process

Topping is defined as the addition of color to the fabric after completing one dyeing process. Sometimes it is found that the dyed fabrics do not match with the standard or buyer approved swatch then it needs to re dyeing, this process is called topping. Tipping sequence is near similar as the full dyeing sequence.

Generally, topping is done for the cotton fabric which is dyed by the reactive dyes. Here, I have given a topping process sequence on the cotton fabric which is dyed by the reactive dyes.

Required amount of water filled

↓

Fabric was loaded and run for 10 min.

↓

Drain

↓

Required amount of water filled

↓

Acetic acid was added for 5 min.

↓

Temperature increased at 60⁰ C

↓

Run for 20 min.

↓

Rinsing for 10 min.

↓

Drain

↓

Require amount of water filled

↓

Wetting agent was added

↓

Temperature increased at 95⁰ C

↓

Run for 30 min.

↓

Ringing for 20 min.

↓

Leveling agent added for 10 min.

↓

Salt dosing

↓

Color dosing for 30 min

↓

Run for 10 min

↓

Soda dosing

↓

Run for 1 hrs

↓

Temperature increase at 60⁰C for 5 min

↓

Run for 10 min

↓

Shade check (OK)

↓

Rinsing for 20 min.

↓

Drain

↓

Acetic acid was added for neutralization for 10 min

↓

Shade check (ok)

↓

Hot wash at 70⁰C

↓

Rinsing for 10 min.

↓

Fixing agent was added for 10 min

↓

Rinsing for 10 min.

↓

Water was filled at required amount

↓

P^H check at 5.5

↓

Softener was added

↓

Final shade checks and run for 20 min

↓

Unloading the dyed fabric

After completing a dyeing process, shade of the dyed fabrics are checked by the quality control department. If the shade of the dyed goods does not match with the buyers approved swatch then they give decision for topping or stripping.

Topping is an additional process which add extra dyeing cost on the dyeing process. So, a textile engineer should be aware about the dyeing of the fabrics.

Bleaching And Scouring Process Of Grey Melange Fabric

Pre-treatment is done for grey melange fabric. I have written about scouring and bleaching process of grey melange yarn in one of my blog post.

Whitening Recipe: Here, I have given a scouring and bleaching process of grey melange with a whitening recipe. I think this will help you to get better pre-treatment result.

Ingredient	Amount
detergent	0.5 g/l
Sequestering agent	1.0 g/l
Anti-creasing	0.8 g/l
Stabilizer	0.8 g/l
Caustic soda	3 g/l
Per oxide	3 g/l
Brightening agent	0.1 g/l

Sequence of scouring and bleaching: Grey melange fabric is pre-treated as the following way.

 

Fabric received from the batching section

↓

Water load

↓

Fabric load

↓

Run 5’ at normal temperature

↓

Drain

↓

Water load

↓

Sequestering, anti-creasing and stabilizer are added at normal temperature

↓

Run 5 minute

↓

Caustic dosing10’ at 40 ⁰C

↓

Steam rise to 70⁰C

↓

Peroxide (60⁰C x10’ dosing)

↓

Temperature 95⁰C

↓

Run time 40’ at 95⁰C

↓

Whitening agent dosing 20’

↓

Run 10’

↓

Sample check

↓

Fabric Unload

So, that’s all about scouring and bleaching process of grey melange fabric.

Process Flow Chart Of Viscose Fabric Dyeing

In dyeing floor, different types of natural, regenerated, synthetic, blended fabrics are dyed. All of the fibers dyeing procedure are not same. For this reason, an textile engineer should have vast knowledge about the different fibers dyeing process.


Viscose fabric or synthetic fabric dyeing procedure is given bellow:

Viscose fabric received from the batching section

↓

Required amount of water was taken into the machine

↓

The fabric was loaded and run for 5-10 minutes in normal temperature

↓

Drain

↓

Required amount of water filled

↓

CK-1,Oxalic acid were added/dosing at hot water for 15 min at 95⁰ C in adding tank

↓

Rinsing for 20 min.

↓

P^H check at 5.5

↓

Leveling agent dosing 10 min. at 55⁰C

↓

Run for 20 min

↓

Salt was added for 10 min

↓

Run for 10 min

↓

Color was dosing for 30 min at 50⁰C

↓

Run for 20 min

↓

Soda was added for 40 min at 50⁰C

↓

Run for 10 min

↓

Temperature increase at 60⁰C

↓

Run for 1 hrs

↓

Shade check (OK)

↓

Rinsing for 30 min.

↓

Acetic acid was added for neutralization for 10 min

↓

Run for 15 min. at 40 ⁰C

↓

Shade check (ok)

↓

Rinsing for 10 mins

↓

Drain

↓

Water was filled at required amount

↓

Hot wash at 95⁰C for 10 min.

↓

Drain

↓

Water was filled at required amount

↓

Cold wash for 20 min.

↓

Drain

↓

Acetic acid added for P^H controlled

↓

P^H check at 5.5

↓

Softener added at 50⁰C

↓

Run for 30 min

↓

Unloading the dyed fabric

Dyeing performance depends on the proper procedure and qualified dyes and chemicals.

Dyeing Procedure Of Polyester Fabric | Disperse Dyeing Process

Polyester fabric dyeing is done by the disperse dyes. Disperse dyes are water insoluble; for this reason dispersing agent is used for make it soluble in the water. We can see the polyester yarn dyeing process for getting more information.

Dyeing Procedure of Polyester Fabric: Here, I have given a dyeing sequence for polyester fabric.

Polyester fabric received from batching section

↓

Required amount of water filled

↓

Fabric was loaded and run for 10 min.

↓

Drain

↓

Required amount of water filled

↓

CK-2 and oxalic acid was added for 5 min.

↓

Run for 20 min. at 80⁰ C

↓

Rinse for 15 min.

↓

Drain

↓

Required amount of water filled

↓

Formic acid added for P^H- controlled

↓

Check P^H at 4.5

↓

Leveling agent (DIF) added for 10 min.

↓

Temperature increase at 60⁰ C

↓

Color/Dyes added for 15 min.

↓

Run for 10 min.

↓

Temperature increase at 130⁰ C for 30 min.

↓

Run for 30 min.

↓

Cooling at 80⁰ C

↓

Shade check

↓

Rinsing for 15 min.

↓

Drain

↓

Required amount of water filled

↓

Hot wash at 80⁰ C

↓

Shade check

↓

Rinsing for 15 min.

↓

Unloading

Disperse dye is suitable for polyester dyeing. It has great dye pick up %. Fastness properties of of the disperse dye is good to excellent.

Process Flow Chart Of Knit Fabric Dyeing With Reactive Dyes

Knit dyeing is near similar as yarn dyeing process but there is some difference in quality measurement. Generally all types of single jersey, double jersey and their derivatives are dyed by the following way.

Here, I have given a discontinuous dyeing process by hot brand reactive dyes. It is more practical process which is done in the dyeing industry. But the dyeing sequence and chemical brand can be different depending on the choice of the manufacturer. Also, some steps of dyeing can be removed or some steps can be added for better dyeing efficiency. Different dyeing parameter is also important to get better dyeing efficiency.

Fabric received from the batching section

↓

Required amount of water was taken into the machine

↓

The fabric was loaded and run for 5-10 minutes in normal temperature

↓

CK-2, D-600/C, SQ-12UD and PH-100(Scouring Chemicals) were added at a time for 5 minutes

↓

Caustic was added at normal temperature for 5 minutes

↓

Temperature increased at 60⁰ C

↓

Hydrogen per Oxide (H₂O₂) was added for 5 minutes

↓

Temperature increased at 95⁰C and continues for 1 hrs

↓

Sample check

↓

Cold wash at 40⁰C for 5-10 minutes

↓

Hot wash at 95⁰C for 5-10 minutes

↓

Required amount of water was loaded

↓

Croak-N was added

↓

Acetic acid was added

↓

Temperature increased at 80⁰C for 15-20 minutes

↓

Cold wash at 40⁰C and drain

↓

Water filled and Acetic acid was added

↓

P^H check at 4.5

↓

Temperature increased at 55⁰C

↓

Enzyme (Bio-EC) was added and   run for 1hrs at 55⁰C

↓

Shade check

↓

Cold wash at 40⁰C and drain

↓

Water filled/Required amount of water was taken

↓

Temperature increased at 95-99⁰C for 5-10 minutes

↓

Cold wash at 40⁰C and drain

↓

Acetic acid was added

↓

P^H check at 4.5

↓

EDX/200B and C/D-600 were added at a time

↓

Salt dosing

↓

Color dosing for 30 min

↓

Run for 10 min

↓

Soda dosing for 40 min

↓

Run for 7 min

↓

Temperature increase at 60⁰C for 5 min

↓

Run for 10 min

↓

Shade check (OK)

↓

Rinsing

↓

Water was filled at required amount

↓

PS-60 was added

↓

Temperature increase at 80⁰ C for 10 min

↓

Hot wash at 90⁰ C for 20 min and shade check in this time (OK)

↓

Rinsing

↓

Water was filled at required amount

↓

Acetic acid was added for neutralization for 10 min

↓

Shade check (ok)

↓

ECO/FRD was added for 10 min

↓

Rinsing

↓

Water was filled at required amount

↓

P^H check at 6.5

↓

(C.W.S) softener was added

↓

Final shade checks and run for 20 min

↓

Unload the dyed fabric

Various types of dyeing faults can be occurring due to wrong process. For this reason, quality control department should be aware about the quality of the fabrics.

Hydro Extractor Machine For Dyed Knit Fabric | Functions Of Hydro Extractor

Hydro extractor machine is the first sequence of finishing unit of dyeing and finishing floor. After completion of dyeing process, dyed fabrics are hold for sometimes before hydro extraction. Hydro extractor machine is important one before de-watering process.



Functions of Hydro-extractor: Hydro extractor machine is used for removing excess water from fabric by centrifugal extraction. About 65% water is removed by this process. The extraction time is about 5-10 minutes. After extraction process, we can find out the efficiency of the hydro extractor. I have written about the hydro extraction process of yarn dyeing and calculating system of efficiency of the hydro extractor in one of my blog post.

Working Procedure Of Hydro Extractor Machine: Hydro extractor machine is like a round basket and it is made of steel. There are a lot of holes on the down side of this basket. After putting the wet fabric in the hydro extractor, it moves and water is removed by the centrifugal extraction. Extract water is drained out through the holes.

Various types of hydro extractor are available in the market. Here, I have present a profile of a hydro extractor. The brand name of the hydro extractor is Dilmenler, which is made of Turkey.

So, choose your hydro extractor machine, which is suitable for removing excess water from the wet knit fabric.

Process Sequence Of Flock Printing On Cotton Fabric

Flock printing is done by depositing various flocks on the surface of the fabric. Flocks means small finely cut natural or synthetic fibers. This flocks are applied on an adhesive coated surface for impart a decorative or functional characteristics to the surface of the fabric.

Flock printing has great scope to produce various attractive designs. Flock printing is generally done on T-Shirt, jewellery boxes, gift, wallpaper or upholstery.

Here, I have given a process flow of flock printing on cotton fabric.



Recipe: This is a sample recipe for flock printing.

Flock paste-----------------90%

Fixer (Nylon) ---------------10%

And, Flock powder (Synthetic or cotton)

Sequence of flock printing: Flock printing is as the following way.

Table preparation

↓

Fabric plaited on the table

↓

Apply flock paste with the help of screen

↓

Flock powder apply with the help of flock gun

↓

Manually dry by hanging for 30min

↓

Curing at 180ºc (belt speed 3 m/min)

↓

Brushing

↓

Delivery

Before flock printing it needs to select the flock for the printing. Size and type of the flock is important one for flock printing.

Process Flow Chart Of Foil Printing With Recipe

Foil printing is a sublimation transfer printing process. Foil printing is done by the help of paper. Foil paper is solid color which is made by buyer requirement. Printing is done in high temperature and pressure. By this printing process man-made and natural both fabric types can be print.



Here, I have given a sequence of foil printing with recipe.

Recipe: It is a sample recipe; this recipe can be changed on the depth of the color and types of dyes use.

Foil paste----------------90%

Fixer---------------------10%

Sequence of foil printing: Foil printing is done as the following sequence.

Fabric preparation

↓

Fabric plaited on the table

↓

Foil gun / Foil paste apply by screen

↓

Dry slightly in air temp / Hand dryer

↓

Apply foil paper on the fabric

↓

Heat apply by heat press m/c (150ºc for 5 sec)

↓

Cooling for 4 sec

↓

Foil paper removed by hand

↓

Delivery

Different type of foil printing is done on T-shirt, Polo-Shirt and other knit and woven fabric. During this printing, the printer should select correct printing paper and should be aware about the ink transfer process from the paper to the fabric.

So, print your fabric by foil printing process and produce various attractive designs like rubber printing or crack printing.

Process Flow Chart Of Crack Printing On Cotton Fabric

Crack printing is a printing method to produce attractive design on the fabric surface. Here rubber is used as the printing paste. It is near similar as rubber printing process but additional crack paste is used before applying rubber printing paste by the screen printer on the cotton fabric.



Here, I have given a printing process of cotton fabric with crack printing process. Also, I have given a sample printing recipe.

Printing Recipe:

Rubber-----------------98%

Fixer-------------------2%

And crack paste / clear

Process Flow Chart Of Crack Printing: Following sequence is the crack printing.

Table preparation

↓

Fabric plaited on the table

↓

Crack paste/clear apply with the help of screen

↓

Dry in air temp or hand dryer m/c (slight)

↓

Printing paste apply with the help of screen

↓

Curing at 190ºc (belt speed 2 m/min)

↓

Delivery

Crack printing can be produced on the surface on T-Shirt, Polo-Shirt and other finished knit fabric and woven fabric.

Process Flow Of Rubber Printing On Cotton Fabric

Rubber printing is one of the important printing processes. After apparel manufacturing, printing is done on the surface of the fabric. Here, I have given the process sequence of rubber printing with recipe.



Recipe:

Rubber----------------60%

Clear------------------38%

Fix---------------------2%

Process Flow Of Rubber Printing: Rubber printing is done as the following way in a printing unit.

Table preparation

↓

Fabric plaited on the table

↓

Rubber printing paste apply with the help of screen

↓

Hanging the fabric for 30 min

↓

Curing at 150ºc (belt speed 5 m/min)

↓

Delivery

That’s all about rubber printing.

Dyed Yarn Drying Process | Drying Mechanism of Stray-field FASTRAN Textile Dryer

Dryer is essential to remove remaining water from the package. About 60-80% water removes by dryer. After passing Hydro section package move into drying section. Following is most used yarn dryer use in yarn dyeing industry.

1. Stray-field FASTRAN Machine


2. GALVANIN (Hot Air Dryer)

Drying Mechanism of Stray-field FASTRAN Textile Dryer: There are lots of dyed yarn dryer for drying the dyed yarn which passed hydro-extractor. I have written about the drying mechanism of Stray-field FASTRAN Textile Dryer.

Direct method of heating are those where the heat is generated within the material itself with ratio frequency and microwave method being typical examples. This method of heating is also referred to as dielectric heating.

Most non-metallic substances undergo a uniform rise in temperature when subjected to a high frequency electric magnetic field. Each time the direction of the applied RF field reverse, so the polarization of the individual molecules within the substance changes. The constant molecular movement causes friction which in turn leads to a rise in temperature. As may be expected the higher the frequency of the electromagnetic field the faster the molecules process, thus creating more friction and consequently more heat is produced.

The frequency of the RF fields generated by devices for dielectric heating is centered on 13.50 MH_Z and 27.12 MH_Z.


Here, I like give a simple idea about the Stray-field FASTRAN Textile Dryer.

Brand Name                : Stray-field

Country Origin             : UK

Supply Voltage            : 380-420

Supply Frequency        : 50 H_Z

Supply Phases             : 3

Supply KVA                 : 230

Supply Power Factor    : 0.9

Maximum Weight         : 3800 Kg

RF Power Output         : 100 kW

Operating Frequency    : 27 MH_Z

Points Need to Consider During Drying: Following points are need to consider during yarn drying. They are:

1. Machine Speed: Machine speed varies according to the shade of the yarn. Conveyor runs in high speed for dark shade and comparatively at low speed for light shade.


2. Feeding System: Plastic package feed in vertical form, but spring package feed in horizontal form because fire can be form by feeding in vertical form.


3. Yarn Type: Same type yarn should run at same settings. Otherwise it can damage the yarn quality. Cotton, Polyester, Acrylic, P/C or CVC yarn should feed separately.


4. Moisture: Machine settings should be according to the amount of moisture remain in the package.

Evaluation of Efficiency of Stray-field Dryer: It needs to know the efficiency of a dyed yarn dryer. For this reason, I have presented a sample calculation of dyed yarn dryer efficiency.

Weight of double yarn package before dyeing               =  1.2 Kg

Weight of double yarn package with water before Dryer = 2.034 Kg

Weight of water in double yarn package before Dryer = (2.034 – 1.2) Kg =  0.834 Kg

Weight of package after Dryer          =          1.2 Kg

Water remain in package after Dryer   =          (1.2 – 1.2) Kg =  0 Kg

Water remove by Dryer                     =          (0.834 – 0) Kg = 0.834kg

Efficiency

=   {(Weight of water before Dryer - Water remain after Dryer) / Weight of water before Dryer}   X 100%

=   {(0.834 – 0) / 0.834} X 100%

=    1 X 100%

=    100 %

Efficiency of Dryer = 100 %

So, yarn dryer is essential for dry the dyed yarn. After drying, dyed yarns transferred for re-winding or random section.

Characteristics Of Process Waste Streams Of Textile Industry | Industrial Effluent Impacts

Textile industry is the huge sector where a large amount of waste streams or effluents are produced. The effluent which is produced in different sector of textile industry is dangerous for the environment. Mainly effluent is produced from desizing, scouring, bleaching, mercerizing, dyeing, printing, finishing, washing and others process. This type of waste water contains harmful chemicals for the environment, for this reason it needs to purify before discharge to the environment. Effluent treatment plant is used for treated the effluent which is come from the textile or other chemical industry.

Characteristics of Process Waste Streams of Textile Industry: Now, I will show you the process unit of textile industry from where effluent is produced, possible pollutant contain in water and nature of waste water. It must help us to get the general concept about the effluent of the textile industry and we can set up ETP for treated the effluent.

Desizing: We know that, size materials are apply on the yarn surface in weaving sector. The removing process of size materials from the fabric is called desizing. Possible pollutant in water is Starch, Glucose, CMC, PVC, Resins, Fats, and Oils etc. The nature of the waste water is high BOD (35-50%) of total.

Scouring: Scouring is the process by which impurities of the textile materials are removed. Possible pollutant in water is NaOH, Na₂CO₃, Waxes, Grease, Fragments of cotton etc. Nature of waste water is strongly alkaline, dark color, high BOD (30%) of total.

Bleaching: Natural color of the textile materials are removed by the bleaching process. Possible pollutant in water is Na(0Ocl)Cl, NaOH, Cl₂, H₂O₂, Na₂O₂, acids etc. Nature of waste water is alkaline, BOD (5%) of the total.

Mercerizing: It is an additional process to improve the physical properties of the fiber. Possible pollutant in water is NaOH, H₂SO₄, Na₂CO₃ etc. Nature of waste water is strongly alkaline, BOD (less than 1%).

Dyeing: Dyeing unit is the main production house of waste water. Waste water which is produced in yarn dyeing, woven dyeing or knit dyeing unit is highly polluted. Possible pollutant in water is various Dyes, Salts, Acids, Alkalis, Soap, and Detergent etc. Nature of waste water is strongly colored, fair BOD (6%) of the total.

Printing: Various type of decorous design is formed by the printing process. Possible pollutant in water is Colors, Pigments, Gums, Oils, Acids, different salt and other auxiliaries. Nature of waste water is highly colored, oily appearance, BOD (6 to 10%) of the total.

Finishing: Different types of finishing are applied in the finishing section. Possible pollutant in water is Traces of Starch, Resins, Softeners, and Stiffeners etc. Nature of waste water is low BOD (2 to 4%) of the total.

To protect the environment from the harmful effect of the effluent of the textile industry, the owner of the industry should set up an Effluent Treatment Plant (ETP).

Working Procedure Of Effluent Treatment Plant (ETP) | Treatment Of Waste Water

Effluent Treatment Plant (ETP) is essential to purify the waste water which is come from different types of manufacturing industry like textile, ternary, dyes and chemical manufacturing industry, pharmaceuticals etc. Different environment saving organizations are trying to protect the environment from the harmful effect of the effluent. Different waste water has different characteristics which pollute the water.

Process flow chart of effluent treatment with effluent treatment plant: Following is the basic structure of effluent treatment plant.

Effluent from different manufacturing industry

↓

Primary Filtration

↓

Cooling and Mixing

↓

Neutralization (by acid or alkali)

↓

Chemical Co-agulation

↓

Settling and Separation of Sludge

↓

Pressure Filtration

↓

Discharge

Now, I like to give a short description about the sequence of operation in effluent treatment plant.

Primary Filtration: It is the first stage of effluent treatment plant, where effluent is come from weaving, dyeing, printing or finishing unit. Here primary filtration is performed to remove solid waste particles.

Cooling and Mixing: In this stage, different types of effluent are mixed and cool down by the help of motor which run a fan.

Neutralization Tank: After cooling and mixing; effluent is transferred to neutralization tank by the help of pump. Here, acid or alkali is mixed to neutralize the effluent. A pH meter is placed in the neutralization tank.

Co-agulant Bath: After neutralization of effluent; effluent is transferred to a co-agulant bath. Here, co-agulant is added with the effluent.

Settling Tank: In here; effluent separates from the water and it found in the lower level of the tank. Effluent is like as sludge.

Pressure Filter: Here, filtration is done under pressure. A certain amount of pressure is created here.

Carbon Filtration: It is an optional filter process.

Discharge to Drain: After completion of all the process, the effluent becomes purify and it becomes safe to drain to the environment.

When treated water is drain to the environment it is checked by the different testing lab. Different standard is maintained during discharge of the treated effluent.

Knit Dyeing | Common Knit Dyeing Faults And Their Way Of Remedies

Knit fabric dyeing process is different from yarn dyeing or woven fabric dyeing process. During knit dyeing; some dyeing faults can be occurred due to wrong operating system. But it can be overcome by applying some techniques.

Knit Dyeing Faults and Their Way of Remedies: Common knit fabric dyeing faults and their way of remedies are given below.

Crack, Rope & Crease Marks

Causes:

1. Poor opening of the fabric rope.


2. Shock cooling of synthetic material.


3. Incorrect process procedure.


4. Higher fabric speed.

Remedies:

1. Pre-Heat setting.


2. Lower rate rising and cooling the temperature.


3. Reducing the m/c load.


4. Higher liquor ratio.


5. Running at a slightly higher nozzle pressure.

Fabric Distortion and Increase in Width

Causes:

1. Too high material speed.


2. Low liquor ratio.

Remedies:

1. By decreasing both nozzle pressure & winch speed.


2. By using high liquor ratio.

Pilling

Causes:

1. Too high mechanical stress on the surface of the fabric.


2. Excess speed during processing.


3. Excess foam formation in the dye bath.

Remedies:

1. By using of a suitable chemical lubricant.


2. By using antifoaming agent.


3. By turn reversing the Fabric before dyeing.

Running Problem

A. Ballooning:

Causes: Seam joining with too densely sewn.

Remedies: By cutting a vertical slit of 10-15 cm in length for escaping the air.

B. Intensive Foaming

Causes: Pumping a mixture of air and water.

Remedies: By using antifoaming agent.

Uneven Dyeing

Causes:

1. Uneven pretreatment (uneven scouring, bleaching & mercerizing).


2. Uneven heat-setting in case of synthetic fibers.


3. Quick addition of dyes and chemicals.


4. Lack of control of dyeing machine.

Remedies:

1. By ensuring even pretreatment.


2. By ensuring even heat-setting in case of synthetic fibers.


3. By slow addition of dyes and chemicals.


4. Proper controlling of dyeing machine.

Shade variation (Batch to batch)

Batch to batch shade variation is common in exhaust dyeing which is not completely avoidable. Even though, to ensure a consistent batch to batch production of shade the following matters should be controlled carefully-

1. Use standard dyes and chemicals.


2. Maintain the same liquor ratio.


3. Follow the standard pretreatment procedure.


4. Maintain the same dyeing cycle.


5. Identical dyeing procedure should be followed for the same depth of the shade.


6. Make sure that the operators add the right bulk chemicals at the same time and temperature in the process.


7. The Ph, hardness and sodium carbonate content of supply water should check daily.

Dye Spot

Causes: Improper mixing of dyestuff in the solution, in right amount of water, at the temperature.

Remedies: We should pass the dissolved dyestuff through a fine stainless steel mesh strainer when adding it to the chemical tank, so that the large un-dissolved particles are removed.

Patchy Dyeing

Causes:

1. Uneven heat in the machine.


2. Improper impregnation of dye liquor due to the low wetting property of the fabric.


3. Dye migration during intermediate dyeing.

Remedies:

1. By proper pretreatment.


2. By adding extra wetting agent.


3. Heat should be same throughout the dye liquor.

Specky Dyeing

Causes:

1. Excessive foam in the dye bath.


2. Fall of water droplets on fabric surface before or after dyeing.


3. In sufficient after treatment.

Remedies:

1. By using antifoaming agent.


2. Sufficient after treatment.


3. By using a good wetting agent in the dye bath.

Roll to Roll Variation or Meter to Meter Variation

Causes:

1. Poor migration property of dyes.


2. Improper dyes solubility.


3. Hardness of water.


4. Faulty m/c speed, etc

Remedies:

1. Use standard dyes and chemicals.


2. Proper m/c speed.


3. Use of soft water.

Crease Mark

Causes:

1. Poor opening of the fabric rope.


2. Shock cooling of synthetic material.


3. If pump pressure & reel speed is not equal


4. Due to high speed m/c running.
   

Remedies:

1. Maintaining proper reel sped & pumps speed.


2. Lower rate rising and cooling the temperature.


3. Reducing the m/c load.


4. Higher liquor ratio.

Dye Spot

Causes:

1. Improper Dissolving of dye particle in bath.


2. Improper Dissolving of caustic soda particle in bath.

 Remedies:

1. By proper dissolving of dyes & chemicals.


2. By passing the dissolved dyestuff through a fine stainless steel mesh strainer, so that the large un-dissolved particles are removed.

Softener Mark

Causes:

1. Improper mixing of the Softener.


2. Improper running time of the fabric during application of softener.


3. Entanglement of the fabric during application of softener.

Remedies:

1. Maintaining proper reel sped & pumps speed.


2. Proper Mixing of the softener before addition.


3. Prevent the entanglement of the fabric during application of softener.

So, we should be careful about the knit dyeing faults as well as yarn dyeing faults.