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Technology and Process in Textile Industry

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Technology and Process in Textile Industry Powered By Docstoc
					            Process modification in the scouring process of textile industry
            Atichart Tanapongpipat, Citapar Khamman, Kejvalee Pruksathorm, Mali Hunsom*
              Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Phaya Thai Road, Bangkok 10330, Thailand




Abstract

   The effects of scouring parameters on the scouring efficiency, including the weight ratio of de-sizing agent and fabric (5e80 g/g fabric),
temperature of de-sizing agent tank (60e90  C) and dipping time (2e8 s), were investigated. The results demonstrated that weight loss of sizing
agent was significantly observed only in the de-sizing agent tank particularly in the first de-sizing tank and was found to a small extent in water
tank. The optimum condition in the scouring machine was found at a de-sizing agent to fabric ratio of 20 g/g fabric, with a temperature of the
first de-sizing agent tank of 80  C, a temperature of the second de-sizing agent tank of 90  C, and dipping time of fabric of 7 s. According to
these conditions, more than 89% of the sizing agent was eliminated and only 3.52 mg/g fabric of sizing agent remained in the scoured fabric
which was in an acceptable range for feeding to the down stream process known as dyeing process. Application of our results to actual textile
plant has shown that there is a cost reduction due to improved utilization of rinse water, chemicals and energy in the process and consequent
decreases in the generation of wastewater. Furthermore, the production capacity was increased from 30 m/min to 34.4 m/min.


Keywords: Cleaner production; Scouring process; Nylon; Sizing agent; Textile industry




1. Introduction                                                                 a large amount of dark color wastewater containing dyestuff,
                                                                                salts, high de-sizing agent oxygen demand (COD) derived
    The concept of cleaner production (CP) has been practiced                   from additives, total dissolved solid (TDS), total suspended
for many years in many countries [1]. Such CP activities in-                    solid (TSS) and fluctuating pH is generated leading to the
clude measures such as pollution prevention, source reduction,                  problem of wastewater management. One factor that can re-
waste minimization and eco-efficiency. At its heart, the                         duce the efficiency in dyeing process is the contamination of
concept is about the prevention rather than the control of pol-                 sizing agent in the fabric at high quantity. Namely, during the
lution [2].                                                                     yarn preparation, various kinds of sizing agent are added into
    In this work, the concept of CP including the waste min-                    the fabric to increase the strength and to reduce the ripping
imization and process modification was carried out in the tex-                   of the yarn during the fabric process. These sizing agents
tile industry because, in our country, the textile was the                      have to be eliminated from the fabric surface before feeding
second largest export commodity registering over US$ 5.2                        such fabric to the down stream process. The process used to
billion in 1999 and more than US$ 5.7 billion in 2003.                          eliminate the sizing agent is known as the scouring process
One principal problem that textile industries have been facing                  and its efficiency depends upon many parameters such as op-
is the re-dyeing process. When such process is carried out, it                  erating condition, type of de-sizing agent, etc. The bioscour-
leads to a loss of many resources such as water, energy, de-                    ing process was used to eliminate the sizing agent from wool
sizing agent and dyestuff, time, man-hour, etc. Moreover,                       and cotton [3]. The results indicated that, for cotton, the pec-
                                                                                tinase enzyme showed excellent activity even in organic me-
                                                                                dia, and the effectiveness of scouring was equivalent or better
 * Corresponding author. Tel.: þ66 2 2187523 5; fax: þ66 2 2555831.             than that achieved by the conventional alkaline process or bi-
   E-mail address: mali.h@chula.ac.th (M. Hunsom).                              oscouring in the aqueous media. On the other hand, for wool,
it was found that felting property and tensile strength of wool          from the fabric surface. The second and third tanks, containing
fabrics treated by protease in reverse micellar system were              chemical agent, were used to eliminate the sizing agent from
superior to those in aqueous media. The commercial enzyme                the fabric structure. The weight ratio of de-sizing agent and
pectinase from Aspergillus niger (Pontypridd, Wales, UK)                 fabric is maintained constant at 40 g/g fabric. The operating
was used to scour raw knitted fabric cotton/polyester (50/               temperatures of both de-sizing agent tanks were maintained
50), 146 g/m2 [4]. It was found that the bioscouring process             approximately at 80  C and 90  C, respectively. The last two
was very sensitive to the surfactant and the pH regulation               tanks were the rinsing water tanks, which were utilized to
whereas temperature seems to be less important. Aly et al.               wash the de-sizing agents on the fabric surface. The tempera-
[5] attempted to scour cotton fabrics made of Giza 70 and                tures of both tanks were controlled at around 80  C and 60  C.
Giza 75 by using various enzymes including bioprip, cellu-               The de-sizing agent used in the process was the liquid mixture
soft L and denilite enzymes. They demonstrated that the                  of NaOH, detergent, and chelating agent. The investigated fab-
scouring was affected by using either bioprip enzyme at                  ric was nylon with initial sizing agent content of 33.02 mg/g
60  C and pH 9 or cellusoft L enzyme at 50  C and pH 5                 nylon. In each experiment, the amount of aqueous solution
for 60 min. Ossola and Galante [6] demonstrated that the                 in each tank was fixed at 1.8 l. The efficiency of the scouring
efficiency of the scouring process of the flax rove in the                 process was determined by using the weight loss of sizing
decreasing order of effectiveness was pectinase > xylanase ¼             agent per unit weight of fabric. High loss of sizing agent refers
galactomannanase ¼ protease > lipase  laccase. The effect               to the high efficiency of the scouring process.
of low temperature plasma treatment on the scouring of nat-
ural fabrics was also investigated [7]. The results demonstrated
that low temperature plasma treatment could increase the                 3. Results and discussion
scouring rate of cotton and wool fabrics. Although the previous
results demonstrated that using various kinds of enzymes seems           3.1. Effect of de-sizing agent and water on the
to be effective to eliminate sizing agent in the fabric, applica-        scouring efficiency
tion of such may not be practical in actual textile industry
due to their high production cost. Therefore, the processes                 The experiments in laboratory scale were preliminarily per-
optimization and modification are the alternative procedures              formed to determine the effect of de-sizing agent and water on
to get the better scouring efficiency and environmentally                 the scouring efficiency by using the dipping time of 8 s, tem-
friendly as the CP concept. In this work, the effects of various         perature of all tanks of 80  C, and weight ratio of de-sizing
parameters in the scouring machine were investigated.                    agent and fabric of 40 g/g fabric. The results as exhibited in
                                                                         Fig. 2(a) showed that the significant weight loss of sizing
                                                                         agent of approximately 18.49 mg/g fabric was obviously ob-
2. Experimental                                                          served in a de-sizing agent tank whereas only 0.5e2.3 mg/g
                                                                         fabric of sizing agent was lost in water tanks. To confirm
    The effects of various parameters including effect of de-siz-        the effect of de-sizing agent on the weight loss of sizing agent,
ing agent and water, weight ratio of de-sizing agent and fabric          similar experiment was carried out by changing the sequence
in the range of 5e80 g/g fabric, temperature of de-sizing agent          of de-sizing agent and water tanks. The results plotted in
tanks (60e90  C), and dipping time (2e8 s) on the scouring              Fig. 2(b) demonstrated that when the fabric was submerged
efficiency were first determined in the laboratory scale by us-            in water from tank 1 to tank 3, only 0.5e1.2 mg/g fabric
ing the equipment emulated from the conventional scouring                was lost in the process. When the fabric was consequently sub-
equipment of textile industry. Fig. 1 displays the conventional          merged in the de-sizing agent tank, approximately 16.72 mg/g
configuration of the scouring equipments employed in the tex-             fabric was lost from the fabric. These results confirm that only
tile industry. It generally consisted of two de-sizing agent             de-sizing agent has strong influence on the weight loss of
tanks and three water tanks. The first tank, containing water,            sizing agent whereas the water has not. From such results, it
was used to wet and clean some impurities such as dust                   demonstrates that only one rinsing water tank was adequate




                                    Tank # 1      Tank # 2       Tank # 3        Tank # 4         Tank # 5
                                     Water        De-sizing      De-sizing        Water            Water
                                                   agent          agent

                                               Fig. 1. Scheme of conventional scouring process.
                                                               (a)                                                                                                            (b)
                                                                                            25                                                                                                                           25




                                                                                                                                                                              Weigh loss of sizing agent (mg/g fabric)
                                                                                                         18.49
                                                                                            20                                                                                                                           20
                                                                Weight loss (mg/g fabric)
                                                                                                                                                                                                                                                                                                16.72

                                                                                            15                                                                                                                           15


                                                                                            10                                                                                                                           10


                                                                                                5                                                                                                                         5
                                                                                                                        2.29
                                                                                                                                                                                                                                    0.51                1.19                    0.88
                                                                                                                                      0.50              0.51          0.47                                                                                                                                     0.02                0.05
                                                                                                0                                                                                                                         0
                                                                                                                                                                                                                                            1                   2                   3           nk                      4                   5
                                                                                                          k



                                                                                                                         1


                                                                                                                                         2


                                                                                                                                                         3



                                                                                                                                                                         4
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                                                                                                                                                                                                                                                                               g
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                                                                                                                                                                                                       W                            W                  W                                         W              W
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                                                                                                                         W


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                                                                                                                                                         W
                                                                                                                                                                                                                                                                        -si
                                                               siz




                                                                                                                                                                                                                                                                De
                                                             e-
                                                            D




                                                                                                                        Fig. 2. Weight loss of sizing agent in de-sizing agent and water tanks.



in the process because it has no influence on the elimination of                                                                                                              process in the actual textile plant as shown in Fig. 4, which
the sizing agent in the fabric as the chemical did. Many water                                                                                                               demonstrates the relationship between the weight loss of de-
tanks lead to high amount of water consumption and high                                                                                                                      sizing agent as a function of parameters of the aqueous
quantity of wastewater generation.                                                                                                                                           solution (temperature, pH, TSS, TDS and alkalinity) in both
    The significance of both de-sizing agent tanks on the                                                                                                                     the chemical tanks. It can be seen that the parameters in the
weight loss of sizing agent was further investigated at a tem-                                                                                                               first chemical tank was more fluctuant than that of the second
perature of 80  C, dipping time of 8 s and weight ratio of                                                                                                                  chemical tank. This fluctuation was due to the contamination
de-sizing agent and fabric of 20 g/g fabric. The results as dis-                                                                                                             of the sizing agent in the aqueous solution. So, this behavior
played in Fig. 3 indicated that the weight loss of sizing agent                                                                                                              can confirm the previous results (Fig. 3) in that the more siz-
was more significantly observed in the first de-sizing agent                                                                                                                   ing agent can be removed in the first de-sizing agent tank than
tank than that in the second de-sizing agent tank, namely,                                                                                                                   in the second tank. Although, the relationship between the
greater than 18 mg/g fabric of sizing agent was eliminated                                                                                                                   weight loss of sizing agent and temperature (Fig. 4(a)) and
in the first tank whereas approximately 0.91 mg/g fabric                                                                                                                      pH (Fig. 4 (b)) of the first de-sizing agent tank was not cer-
was dislodged in the second de-sizing agent tank. These re-                                                                                                                  tainly observed, the TSS, TDS, M-alkalinity and P-alkalinity
sults can be confirmed by the data collected from scouring                                                                                                                    showed the relationship with the weight loss of sizing agent.
                                                                                                                                                                             Namely, high values of TSS, TDS, M-alkalinity and P-alkalinity
                                                                                                                                                                             led to high weight loss of sizing agent such as sample num-
                                             25                                                                                                                              bers 2, 19, and 20. Likewise low values of them conducted
                                                                                                                                                                             small weight loss of sizing agent such as sample 18. This
                                                                                                                                                                             tendency, however, was not clear for all samples because it
 Weight loss of sizing agent (mg/g fabric)




                                             20                18.49                                                                                                         relates to various parameters in scouring process such as con-
                                                                                                                                                                             centration of de-sizing agent at interval, operating tempera-
                                                                                                                                                                             ture, etc.
                                             15

                                                                                                                                                                             3.2. Effect of weight ratio of de-sizing agent and fabric
                                             10
                                                                                                                                                                                According to the above results, the de-sizing agent has sig-
                                                                                                                                                                             nificant effect on the efficiency of scouring process. The actual
                                                                                                                                                                             ratio of de-sizing agent to fabric used in the textile industry
                                              5
                                                                                                                                                                             was about 40 g/g fabric. In this part, the author attempted to
                                                                                                                                             0.91                            reduce the de-sizing agent cost in the actual process by reduc-
                                                                                                                                                                             ing the de-sizing agent to fabric ratio. The experiment was
                                              0
                                                                                            1                                                       2                        conducted in a laboratory scale with the weight ratio of de-
                                                                n      k#                                                                   n k#                             sizing agent and fabric in the range of 5e80 g/g fabric at a tem-
                                                             Ta                                                                          Ta
                                                                                                                                                                             perature of 80  C and a dipping time of 8 s. The results plotted
                                             Fig. 3. Weight loss of sizing agent in both de-sizing agent tanks.                                                              in Fig. 5 demonstrated that weight loss of sizing agent was
        (a)                                                                                                                                     (b)
                              140                                                         80                                                                           20                                                     80
                                                                      Tank 1                                                                                           18                                 Tank 1
                                                                                          70                                                                                                                                  70
                              120                                     Tank 2                                                                                                                              Tank 2
                                                                                                                                                                       16




                                                                                                                                                                                                                                       Weight loss (mg/g fabric)
                                                                                                                                                                                                                              60




                                                                                               Weight loss (mg/g fabric)
                                                                      Weight loss         60                                                                                                              Weight loss
                              100                                                                                                                                      14
       Temperature (°C)




                                                                                          50                                                                                                                                  50
                                                                                                                                                                       12
                               80




                                                                                                                                                 pH
                                                                                          40                                                                           10                                                     40
                               60                                                                                                                                      8                                                      30
                                                                                          30
                                                                                                                                                                       6
                               40                                                                                                                                                                                             20
                                                                                          20                                                                           4
                               20                                                                                                                                                                                             10
                                                                                          10                                                                           2

                                                                                                                                                                       0                                                      0
                                0                                                         0                                                                                 0   5   10     15        20       25         30
                                    0   5   10        15         20       25         30
                                                                                                                                                                                     Sample number
                                                 Sample number

     (c)                                                                                                                   (d)
                              350                                                         80                                                    20,000                                                                            80
                                                                      Tank 1                                                                                                                               Tank 1
                              300                                                         70                                                                                                                                      70
                                                                      Tank 2                                                                                                                               Tank 2




                                                                                                                                                                                                                                                    Weight loss (mg/g fabric)
                                                                                               Weight loss (mg/g fabric)



                                                                      Weight loss         60                                                    15,000                                                     Weight loss            60
                              250
                                                                                                                            TDS (mg/g fabric)
      TSS (mg/g fabric)




                                                                                          50                                                                                                                                      50
                              200
                                                                                          40                                                    10,000                                                                            40
                              150
                                                                                          30                                                                                                                                      30
                              100
                                                                                          20                                                     5,000                                                                            20

                              50                                                          10                                                                                                                                      10

                               0                                                          0                                                                            0                                                          0
                                    0   5   10        15         20       25         30                                                                                     0   5   10     15        20        25         30
                                             Sample number                                                                                                                           Sample number

      (e)                                                                                                                                        (f)                   8                                                       80
                                8                                                         80
                                                                       Tank 1                                                                                                                              Tank 1
                                                                                          70                                                                                                                                   70
                                                                       Tank 2                                                                                                                              Tank 2
                                                                                               Weight loss (mg/g fabric)




                                                                                                                                                                                                                                               Weight loss (mg/g fabric)
                                6                                      Weight loss        60                                                                           6                                   Weight loss         60
        M-alkalinity (mg/l)




                                                                                                                                                 P-alkalinity (mg/l)




                                                                                          50                                                                                                                                   50

                                4                                                         40                                                                           4                                                       40

                                                                                          30                                                                                                                                   30

                                2                                                         20                                                                           2                                                       20

                                                                                          10                                                                                                                                   10

                                0                                                         0                                                                            0                                                       0
                                    0   5   10         15        20       25         30                                                                                     0   5   10     15        20        25        30
                                             Sample number                                                                                                                           Sample number

      Fig. 4. Physical properties of aqueous solution in the chemical tanks of the scouring process of textile industry and weight loss of sizing agent.




observed when the ratio of de-sizing agent and fabric increased                                                                           agent to fabric ratio from 14 to 20 g/g fabric. It increased
from 5 to 14 g/g fabric, namely, it slightly increased from                                                                               from 18.2 mg/g fabric to 24.3 mg/g fabric or approximately
16.7 mg/g fabric to 18.2 mg/g fabric or approximately 7e                                                                                  to 33.5%. Further increasing ratio of de-sizing agent to fabric
9%. However, the significant increase in the weight loss of                                                                                to 80 g/g fabric cannot promote the increase of weight loss of
sizing agent was then found when increasing the de-sizing                                                                                 sizing agent in fabric. According to this study, it can be said
                                                                                                             30




                                                                    Weight loss (mg sizing agent/g fabric)
                                                                                                                                                                                                                   24.3          24.4          24.2        24.0
                                                                                                             25
                                                                                                                                                                  22.3


                                                                                                             20                      18.0          18.2
                                                                                                                       16.7


                                                                                                             15


                                                                                                             10


                                                                                                              5


                                                                                                              0
                                                                                                                         5           10            14             17                                               20            40            60          80
                                                                                                                                                          Chemical : Fabric (g/g fabric)

                                                                                                                    Fig. 5. Weight loss of sizing agent as a function of de-sizing agent to fabric ratio.



that the optimum de-sizing agent to fabric ratio was found at                                                                                                            loss of sizing agent obtained from this condition increased
a ratio of 20 g/g fabric which is approximately 50% less than                                                                                                            slightly from 18.5 mg/g fabric at 60  C to approximately
that used in actual textile process.                                                                                                                                     24.4 mg/g fabric at 80  C and afterwards it was rather
                                                                                                                                                                         constant. On the other hand, the effect of temperature in the
3.3. Effect of temperature in de-sizing agent tanks                                                                                                                      second de-sizing agent tank was also studied in the range of
                                                                                                                                                                         60e80  C by using the fixed temperature of the first chemical
   In this part, the experimental set up was imitated from the                                                                                                           tank. The results demonstrated in Fig. 6(b) referred that the
actual process consisting of three water tanks and two de-                                                                                                               weight loss of sizing agent was constant in the range of
sizing agent tanks. The first water tank was used for wetting                                                                                                             operating temperatures of 60e80  C, but it would increase
and cleaning the fabric from impurity such as dust. The next                                                                                                             to approximately 29.5 mg/g fabric at 90  C. From this inves-
two tanks were de-sizing agent tanks containing de-sizing                                                                                                                tigation, it can be said that optimum temperatures in the first
agent with weight ratio of 20 g/g fabric and the last two tanks                                                                                                          and second de-sizing agent tanks were 80  C and 90  C,
containing water was used to eliminate the de-sizing agent on                                                                                                            respectively.
fabric surface. The temperature in all water tanks was con-
trolled at 80  C and the temperature of both de-sizing agent                                                                                                            3.4. Effect of dipping time
tanks was varied in the range of 60e90  C. Fig. 6(a) demon-
strates the effect of temperature in the first chemical tank in                                                                                                              The dipping time indicates the time that the fabric is sub-
the range of 60e90  C by using constant temperature of the                                                                                                              merged in the solution. The shorter dipping time means the
second chemical tank (80  C). It showed that the weight                                                                                                                 rapid velocity of fabric fed into the scouring machine.


                     (a)                                                                                                                                                 (b)
                                                               35                                                                                                                                                 35
                                                                                                                                                                         Weight loss (mg sizing agent/g fabric)
                      Weight loss (mg sizing agent/g fabric)




                                                                                                                                                                                                                                                                  29.5
                                                               30                                                                                                                                                 30
                                                                                                                                            24.4           25.1
                                                                                                                                                                                                                          23.9          24.0          24.6
                                                               25                                                                                                                                                 25
                                                                                                                              21.3
                                                                                                             18.5                                                                                                 20
                                                               20

                                                               15                                                                                                                                                 15

                                                               10                                                                                                                                                 10

                                                                5                                                                                                                                                  5

                                                                0                                                                                                                                                  0
                                                                                                             60               70            80              90                                                             60           70            80          90
                                                                                                             Temperature in the 1st chemical tank (ºC)                                                                    Temperature in the 2nd chemical tank (ºC)

Fig. 6. Weight loss of sizing agent as a function of temperature at (a) constant temperature of the second chemical tank of 80  C and (b) constant temperature of the
first chemical tank of 80  C.
                                            35                                                                   Table 1
                                                                                                                 Comparison of conditions and characteristics of scoured fabric between this
                                                                                            29.07        29.50   work and actual textile plant
                                            30                                27.44
 Weigh loss of sizing agent (mg/g fabric)




                                                                                                                 Characteristics and conditions           This work          Actual textile
                                                                 25.85
                                                   24.35                                                                                                                     plant
                                            25
                                                                                                                 Weight ratio of de-sizing agent          20                 40
                                                                                                                   and fabric (g/g fabric)
                                            20                                                                   Temperature of the first de-sizing        80                 80
                                                                                                                   agent tank ( C)
                                                                                                                 Temperature of the second de-sizing      90                 90
                                            15
                                                                                                                   agent tank ( C)
                                                                                                                 Dipping time (s)                         7 (34.4 m/min)     8 (30.0 m/min)
                                            10                                                                   Weigh loss of sizing agent               29.50             24.92e26.73
                                                                                                                   (mg/g fabric)
                                                                                                                 Residual sizing agent in scoured           3.52             6.29e8.10
                                            5                                                                      fabric (mg/g fabric)
                                                                                                                 Operation cost
                                                                                                                   Chemical reagent (USDa/m2 fabricb)       0.361             0.722
                                            0
                                                     2            4             6            7             8       Water (USD/m2 fabric)                    0.116             0.232
                                                                                                                   Wastewater management                    0.071             0.141
                                                                         Dipping time (s)
                                                                                                                 (USD/m2 fabric)
                                            Fig. 7. Weight loss of sizing agent as a function of dipping time.     Energy cost (USD/m2 fabric)              0.004             0.007
                                                                                                                  a
                                                                                                                      1 USD ¼ 35.8 Baht.
                                                                                                                  b
                                                                                                                      Fabric with 1.524 m width.
Similarly, it indicates the large production capacity per unit
time. Fig. 7 shows the weight loss of sizing agent on fabric
as a function of dipping time in the range of 2e8 s at de-siz-
                                                                                                                 optimum condition leads to the decrease of operation cost of
ing agent to fabric ratio of 20 g/g fabric, temperature of the
                                                                                                                 approximately 50%.
first de-sizing agent tank of 80  C and temperature of the
second de-sizing agent tank of 90  C. The results indicated
that when the dipping time increased from 2 s to 7 s, the                                                        4. Conclusion
weight loss of sizing agent increased slightly from 24.35
mg/g fabric to approximately 29.07 mg/g fabric and then                                                             The concept of CP concerned with waste minimization and
became quite constant. Therefore, it can be said that the op-                                                    process modification was performed in the scouring process of
timum dipping time was around 7 s, which was correspond-                                                         textile industry. The results indicated that only the de-sizing
ing to the velocity of fabric in scouring machine of around                                                      agent had significant effect on weight loss of sizing agent
34.4 m/min. At this condition, greater than 89% of sizing                                                        whereas water did not. Therefore, one rinsing water tank
agent was eliminated from the fabric surface and the amount                                                      was enough to clean the de-sizing agent from the fabric.
of the sizing agent remaining in the fabric was lower than                                                       This decreased the quantity of wastewater discharged from
3.52 mg/g fabric which is acceptable to feed into the down                                                       the process by approximately 20%. For the chemical tanks,
stream process.                                                                                                  the first de-sizing agent tank in the scouring machine had
   Table 1 exhibits the comparison of operating conditions                                                       more influence on the weight loss of sizing agent than that
and properties of the scoured fabric between laboratory                                                          of the second de-sizing agent tank. Namely, the weight losses
and the actual textile processes. It showed that the ratio of                                                    of sizing agent were approximately 24 mg/g fabric and
de-sizing agent to fabric used in this work was lower than                                                       0.91 mg/g fabric for the first and the second de-sizing agent
that of the actual process of approximately 50%. The dip-                                                        tanks, respectively. The optimum condition in the scouring
ping time which was corresponding to the velocity of fabric                                                      process was found at the de-sizing agent to fabric ratio of
in the scouring machine was faster than that in actual pro-                                                      20 g/g fabric, temperature in the first and second de-sizing
cess of around 15%. It means that the production capacity                                                        agent tanks of 80  C and 90  C, respectively, and the dipping
can be increased by operating the system at our find out con-                                                     time of 7 s. Application of our results reduces the amount of
dition. By employing this condition, more than 89% of siz-                                                       chemicals, rinse water and energy used in the process. In ad-
ing agent was eliminated from the fabric and the remaining                                                       dition, the production capacity was increased from 30 m/min
sizing agent in fabric was approximately 3.52 mg/g fabric                                                        to 34.4 m/min. The barrier that may be faced when this im-
which is lower than that obtained by using the actual textile                                                    provement is carried out is the variation of the amount of
plant.                                                                                                           the sizing agent in the fabric surface in the actual textile plant.
   The operation costs used in the new optimum condition                                                         When this situation occurs, the producers have to use the ratio
including the costs of rinsing water, chemicals, wastewater                                                      of the de-sizing agent to fabric greater than 20 g/g fabric or
management and energy were also calculated and compared                                                          with safety factor of approximately 20e50%. This will lead
with that used in the conventional process as demonstrated                                                       to a decrease in savings from the new process. The other bar-
in Table 1. It can be seen that the application of the new                                                       rier is that this condition can only be used with nylon.
Acknowledgement                                                        [2] International institute for sustainable development. Available from:
                                                                           <http://www.bsdglobal.com/tools/bt_cp.asp>; 2005.
                                                                       [3] Sawada K, Ueda M. Enzyme process of textiles in reserve micellar solu-
   The authors would like to thank the Thailand Research                   tion. J Biotechnol 2001;9:263e9.
Fund under the IRPUS projects for the financial support of              [4] Calafell M, Garriga P. Effect of some process parameters in the enzymatic scour-
our project and the Cleaner Technology Consortium at Chula-                ing of cotton using an acid pectinase. Enzyme Microb Technol 2004;34:326e31.
longkorn University.                                                   [5] Aly AS, Moustafa AB, Hebeish A. Bio-technological treatment of cellu-
                                                                           losic textiles. J Clean Prod 2004;12:697e705.
                                                                       [6] Ossola M, Galante YM. Scouring of flax rove with the aid of enzymes.
References                                                                 Enzyme Microb Technol 2004;34:177e86.
                                                                       [7] Sun D, Stylios GK. Effect of low temperature plasma treatment on
[1] Kjaerheim G. CP and sustainability. J Clean Prod 2005;13:329e39.       the scouring and dyeing of natural fabrics. Text Res J 2004;74:751e6.

				
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