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20320130405005

  1. 1. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 33 MITIGATION OF COLOUR AND COD FROM TEXTILE WASTEWATER BY HMS, POLYMERIC COAGULANTS AND AIDS – INCLUDING LONGITUDINAL STUDY Mukherjee. S.* 1,2 , Bhattacharya A. K. 3 , Mandal. S. N.1 1 National Institute of Technical Teachers’ Training and Research, Kolkata, India 2 Ramakrishna Mission Shilpapitha, Belgharia, Kolkata, India 3 Tellab Chemicals, Mumbai, India ABSTRACT Textile is one of the most polluting industries in the world. The objective of this study was to evaluate hydrolyzing metal salts (HMS) in the form of Al2(SO4)3, 16H2O and FeCl3 independently and also in conjunction with polymeric coagulant (PACl) and recently developed cationic coagulants (Telfloc 01, Telfloc 185K and Telfloc 2840) for clarifying textile wastewater. Though parameters like pH, TSS, BOD, Sludge Volume were studied the major emphasis was on the two principal parameters Colour and COD. The experimental results show that each of the HMS was good in reducing colour, COD and other parameters significantly (more than 90% for colour and 70% for COD). However the generated sludge volumes were large (about 300mL/L). However the use of Telfloc 01, Telfloc 2840 in addition to HMS reduced the sludge volume considerably (about 100mL/L) while achieving colour and COD removal about 80% and 70% respectively. Addition of PACl with both HMS and Telfloc 01 & Telfloc 2840 in low dosages achieved colour and COD removal comparable to that of HMS, Telfloc 01 and Telfloc 2840. When only cationic polymeric coagulants and aids were used in the form of Telfloc 185K, Telfloc 01 and Telfloc 2840, colour and COD removal of about 90% and 80% respectively were achieved. Keywords: dye; coagulant; flocculant; hydrolyzing metal salt; polymeric coagulant; cationic coagulant. 1. INTRODUCTION Textile industry is one of the biggest users of water and discharges coloured wastewater of extremely heterogeneous composition and great quantity of toxic materials. This effluent if directly thrown into the water bodies will pollute the water and affects the flora and fauna. Effluent from INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND TECHNOLOGY (IJCIET) ISSN 0976 – 6308 (Print) ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October, pp. 33-41 © IAEME: www.iaeme.com/ijciet.asp Journal Impact Factor (2013): 5.3277 (Calculated by GISI) www.jifactor.com IJCIET ©IAEME
  2. 2. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 34 textile industries contains different types of dyes, which because of high molecular weight and complex structure shows very low biodegradability [9, 12, 15, 18]. Reactive dyes are widely used in textile industry because of their high stability during washing and because of their simple dying procedure. These being the main class of dyes used to dye cellulose and cotton [3]. However these dyes are highly soluble in water and also have low levels of fixing to fibers, most of their initial concentration being lost to the effluent [8]. Apart from this large number of chemical constituents such as alkali, acids, bleaching materials, enzymes, starch, resins, solvents, waxes, oils etc. are used in various steps during textile processing and finally comes out in the effluent after their consumption. Textile industries typically generate 200-350 m3 of wastewater per ton of finished product [11,20] resulting in an average pollution of 100 kg COD per ton of fabric [14]. Typical characteristics of textile industry wastewater generally include wide range of pH, COD, dissolved solids and strong colour [5, 6, 7, 16, 19]. Different physico-chemical methods in the form of pretreatment, post treatment or main treatment have been investigated by different researchers all over the world. However in wastewater treatment coagulation as pretreatment is regarded as the most successful [13,17]. It also involves low capital cost [1,10]. However, very limited work has been carried out on the decolourisation of textile wastewater containing multiple dyes. Present study is designed to verify the efficiency in terms of removal of colour and COD from actual textile plant effluent, of some less used poly-electrolytes either independently or in conjunction to hydrolyzing metal salts (HMS) traditionally used in coagulation of wastewater. As the parameters for textile wastewater vary widely, a longitudinal study of textile wastewater was imperative. Accordingly removal of colour and COD was studied using the successful coagulants from cross sectional study. 2. MATERIALS AND METHODS Composite samples were obtained from a textile industry effluent pond. The samples are collected in polytetrafluoroethylene (PTFE) containers. The samples were labeled, sealed and tested as soon as possible after collection. The sample collection, transport and preservation were done in accordance to section 1060B and 1060C of Standard Methods for the Examination of Water and Wastewater APHA, AWWA, WEF. The characteristics of the raw effluent are presented in Table-1. Chemical coagulation flocculation experiments were performed using hydrolyzing metal salts (HMS) namely Al2(SO4)3,16H2O and FeCl3 supplied by Merck Specialties Private Limited, India and Poly Aluminum Chloride (PACl) (Commercial) supplied by GRASIM, India. Telfloc 01, Telfloc 185-K and Telfloc 2840 were obtained from Tellabs Chemicals Private Limited, India. Characteristics of PACl Characteristics Value Appearance Pale yellow powder Bulk density 0.75 ± 0.10 pH of 1% solution (w/v) 3.5 – 5.0 Al2O3 30 ± 1% Sulphate Nil The Standard Practice for Coagulation-flocculation Jar Test of Water was first adopted in 1980 and re-approved in 1999 [4]. Since coagulant interactions are very complex, laboratory studies
  3. 3. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 35 are needed to determine the suitable coagulant, optimal dosage, duration and intensity of mixing and flocculation. The coagulation and flocculation experiments were carried out by Jar test (by Programmable Phipps and Birds Jar Test Apparatus, Richmond, VA USA Model – PB – 900). Based on a series of studies the following operating conditions were selected • Rapid mixing speed 150 rpm • Rapid mixing time 1 min. • Flocculation speed 25 rpm • Flocculation time 20 min. • Settling time 30 min. The analytical methods were adopted from the Standard Methods for the Examination of Water and Wastewater [2]. Telfloc 2840 was added in the flocculation stage while all the other coagulants were added before rapid mixing. The supernatant obtained after settling in Jar Tester were taken for measurement of different parameters. pH and dissolved oxygen (DO) were determined using HACH multi-parameter meter (Model HQ40d) using glass electrode & LBOD probe respectively. COD was measured using COD digester (Model DRB 200 by HACH, USA) followed by UV-VIS Spectrophotometer (DR 5000 by HACH, USA). True colour was measured by UV-VIS Spectrophotometer (DR 5000) after filtration through 0.45µm filter under suction by Cole-Palmer Air Cadet pump (Model no. 07530-50). TABLE -1 Raw effluent characteristic Parameters Value pH 9.1 ± 0.8 Total Suspended Solid (TSS) 272 ± 52 mg/L True Colour 90 ± 11 mg/L Pt-Co Chemical Oxygen Demand (COD) 1475 ± 201 mg/L Bio-chemical Oxygen Demand 286 ± 50 mg/L 3. RESULTS AND DISCUSSIONS 3.1 Cross sectional study 3.1.1 Impact on Colour Figure 1 Figure 2 500 1000 1500 2000 2500 3000 10 20 30 40 50 60 70 80 90 100 Al2 (SO4 )3 FeCl3 Dosages (in mg/L) --> (Al2 (SO4 )3 ,16H2 O / FeCl3 ) TrueColour(%decrease)--> 0 50 100 150 200 250 10 20 30 40 50 60 70 80 90 100 TrueColour(%decrease)--> Dosages of Telfloc 01 (in ppm) --> (Along with Al2 (SO4 )3 ,16H2 O / FeCl3 -1000ppm and Telfloc2840- 5ppm) Al2 (SO4 )3 FeCl3
  4. 4. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 36 Figure 3 Figure 4 Colour removal increased with increasing dosages of HMS and goes beyond 90 percent. However such high percentage of colour removal accompanied very high volume of sludge. Telfloc 01 when applied in varying dosages along with fixed dosages of HMS and Telfloc 2840. The removal of colour varied from about 60 to 80 percent for Al2(SO4)3,16H2O and 45 to 75 percent for FeCl3. PACl when used with fixed quantity of HMS, Telfloc 01 and Telfloc 2840 removed colour from about 65 to 80 percent, with the slope of the curves being mild and the curves being similar for both the HMS. Colour removal was highly satisfactory when Telfloc 185K was applied with fixed dosages of Telfloc 01 and Telfloc 2840. The range varied from about 88 percent and went beyond 95 percent. However the increase was not significant beyond a dosage of 1000 ppm of Telfloc 185K. 3.1.2 Impact on COD Figure 5 Figure 6 500 1000 1500 2000 2500 3000 0 10 20 30 40 50 60 70 80 90 Al2 (SO4 )3 FeCl3 Dosages (in mg/L) --> (Al2 (SO4 )3 ,16H2 O / FeCl3 ) COD(%decrease)--> 0 50 100 150 200 250 0 10 20 30 40 50 60 70 80 90 COD(%decrease)--> Dosages of Telfloc 01 (in ppm) --> (Along with Al2 (SO4 )3 ,16H2 O / FeCl3 -1000ppm and Telfloc2840- 5ppm) Al2 (SO4 )3 FeCl3 0 50 100 150 200 250 300 350 400 450 500 550 600 10 20 30 40 50 60 70 80 90 100 TrueColour(%decrease)--> Dosages of PACl (in mg/L) --> (Along with Al2 (SO4 )3 ,16H2 O / FeCl3 -1000ppm, Telfloc01- 50ppm and Telfloc2840- 5ppm) Al2 (SO4 )3 FeCl3 400 600 800 1000 1200 1400 1600 10 20 30 40 50 60 70 80 90 100 Dosages of Telfloc 185K (in ppm) --> (Along withTelfloc 01 - 250ppm & Telfloc 2840 - 10ppm) TrueColour(%decrease)-->
  5. 5. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 37 Figure 7 Figure 8 Performance of FeCl3 for COD removal was better than Al2(SO4)3,16H2O. For FeCl3, COD removal increased rapidly upto dosages of 1500 mg/L, after that it became asymptotic. For Al2(SO4)3, removal efficiency increased gradually. The difference may be attributed to the phenomenon of sweep flocculation as FeCl3 generates more sludge at lower dosages compared to Al2(SO4)3. With increase in dosages of Telfloc 01 along with fixed dosages of FeCl3 and Telfloc 2840 there is not much improvement in COD reduction. Whereas when Al2(SO4)3 was added in place of FeCl3 initially COD removal percentage increased rapidly with stabilization at higher dosages. PACl was not very effective in increasing the COD removal percentage when added with fixed dosages of HMS, Telfloc 01 and Telfloc 2840. When only synthetic coagulants like Telfloc 185K was used with fixed dosages of Telfloc 01 and Telfloc 2840, COD removal increased rapidly upto dosage of 1000 ppm thereafter attaining a stable value with minor increase. 3.1.3 Variation of Sludge Volume Figure 9 Figure 10 400 600 800 1000 1200 1400 1600 0 10 20 30 40 50 60 70 80 90 Dosages of Telfloc 185K (in ppm) --> (Along withTelfloc 01 - 250ppm & Telfloc 2840 - 10ppm) COD(%decrease)--> 0 50 100 150 200 250 300 350 400 450 500 550 600 0 10 20 30 40 50 60 70 80 90 COD(%decrease)--> Dosages of PACl (in mg/L) --> (Along with Al2 (SO4 )3 ,16H2 O / FeCl3 -1000ppm, Telfloc01- 50ppm and Telfloc2840- 5ppm) Al2 (SO4 )3 FeCl3 500 1000 1500 2000 2500 3000 0 100 200 300 400 500 Al2 (SO4 )3 FeCl3 Dosages (in mg/L) --> (Al2 (SO4 )3 ,16H2 O / FeCl3 ) SludgeVolume(mL/L)--> 0 50 100 150 200 250 0 100 200 300 400 500 SludgeVolume(mL/L)--> Dosages of Telfloc 01 (in ppm) --> (Along with Al2 (SO4 )3 ,16H2 O / FeCl3 -1000ppm and Telfloc2840- 5ppm) Al2 (SO4 )3 FeCl3
  6. 6. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 38 Figure 11 Figure 12 As expected sludge volumes were higher reaching upto about 500 mL/L with increasing dosages of HMS. However when Telfloc 01 was added to fixed dosages of HMS and Telfloc 2840, the sludge volume remained within 200 mL/L. PACl when added to fixed dosages of HMS, Telfloc 01 and Telfloc 2840 kept the sludge volume below or near 200 mL/L. Varying dosages of Telfloc 185K with fixed dosages of Telfloc 01 and Telfloc 2840 maintained the sludge volume between about 100 mL/L to 200 mL/L. 3.2 Longitudinal study TABLE -2 Raw effluent characteristics for different samples Parameters pH TSS True colour COD BOD Sample 1 7.42 114 260 939 167.3 Sample 2 7.33 147 1050 980 134.3 Sample 3 7.36 117 51 573 137.9 Sample 4 9.43 124 85 1839 322.7 Sample 5 8.68 118 172 937 245.9 Sample 6 9.04 163 457 907 193.1 TABLE -3 Combinations adopted for treating different samples Coagulants Al2(SO4)3,16H2O PACl Telfloc 01 Telfloc 185K Telfloc 2840 Combination 1 1250 ppm 75 ppm 5 ppm Combination 2 1500 ppm 500 ppm 50 ppm 5 ppm Combination 3 250 ppm 500 ppm 10 ppm Combination 4 250 ppm 1000 ppm 10 ppm Combination 5 250 ppm 1500 ppm 10 ppm 0 50 100 150 200 250 300 350 400 450 500 550 600 0 100 200 300 400 500 SludgeVolume(mL/L)--> Dosages of PACl (in mg/L) --> (Along with Al2 (SO4 )3 ,16H2 O / FeCl3 -1000ppm, Telfloc01- 50ppm and Telfloc2840- 5ppm) Al2 (SO4 )3 FeCl3 400 600 800 1000 1200 1400 1600 0 100 200 300 400 500 Dosages of Telfloc 185K (in ppm) --> (Along withTelfloc 01 - 250ppm & Telfloc 2840 - 10ppm) SludgeVolume(mL/L)-->
  7. 7. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 39 3.2.1 Removal of colour Figure 13 Percentage of colour removal was studied for five combinations of coagulants / flocculants and coagulation aids. The results show that for all the samples the colour removal was the best with combination five i.e. with synthetic polymeric coagulants and aids in the form of Telfloc 185K – 1500 ppm, Telfloc 01 – 250 ppm and Telfloc 2840 – 10 ppm. Colour removal increased with increasing dosages of Telfloc 185K with the removal reaching above ninety percent for almost all the cases at Telfloc 185K concentration of 1500 ppm. 3.2.2 Removal of COD Figure 14 0 10 20 30 40 50 60 70 80 90 1 00 sa m p le1 sa m p le2 sa m p le3 sa m p le4 sa m p le5 sa m p le6 Truecolor(%decrease)--> D iff e re n t s a m p le s C om b.1 C om b.2 C om b.3 C om b.4 C om b.5 0 10 20 30 40 50 60 70 80 90 1 00 sa m pl e1 sa m pl e2 sam pl e3 sa m p le4 sa m p le5 sa m p le6 COD(%decrease)--> D ifferent s am ples C om b.1 C om b.2 C om b.3 C om b.4 C om b.5
  8. 8. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 40 From figure 14 it is observed that COD removal was the best achieved with the combination two i.e. Al2(SO4)3,16H2O – 1500 ppm, PACl – 500 ppm, Telfloc 01 – 50 ppm and Telfloc 2840 – 5 ppm and went beyond 70 percent for all the cases. This may be due to the sweep flocculation combined with high volume of sludge. Combination five came a close second with COD removal percentage close to 70 percent for three samples and above 70 percent for the other three. However the sludge volume was considerably lower with combination five in all the cases compared with combination two. 4. CONCLUSIONS Based on the results and discussions it may be concluded that colour removal was best attained when Telfloc 185K was used along with Telfloc 01 and Telfloc 2840. Colour removal was also good at high HMS dosages but the resultant sludge volume became enormous. The combination five of Telfloc 185K – 1500 ppm, Telfloc 01 – 250 ppm & Telfloc 2840 – 10 ppm was proved to be the best among all combinations when applied on different samples. Maximum COD removal attained was between about 70 to 80 percent in each of the combinations at some dosages of the coagulants during the cross sectional studies. During longitudinal.study with different types of samples, combination two was proved to be the best. However combination five was the next best option with COD removal reaching near 70 percent for three samples and above 70 percent for the rest three. Considering the sludge volume, combination five may be considered as the optimum choice for treating different types of textile effluents. Overall this research evaluated different coagulants and aids vis-à-vis their efficiency in removing different parameters of the textile wastewater. Considering the major parameters such as Colour and COD the combination of Telfloc 185K with Telfloc 01 and Telfloc 2840 at some dosages proved to be very efficient in treating this type of textile wastewater. REFERENCES [1] Y. Anjaneyulu, N.S. Chary, D.S.S. Raj, Decolourization of industrial effluents – available methods and emerging technologies – a review, Reviews in Environmental Science and Biotechnology 4 (2005) 245- 273. [2] APHA, Standard Methods for the Examination of water and Wastewater. 22nd ed. American Public Health Association, American Water Works Association, Water Environment Federation, Washington, DC, 2012. [3] Araújo FVF, Yokoyama L. Remoc¸ ão de cor em soluc¸ ões de corantes reativos por oxidac¸ ão com H2O2/UV, Quím Nova 29 (2006) 4-11. [4] ASTM, Standard Practice for Coagulation-Flocculation Jar Test of Water E1-1994 R(1995), D 2035-80. Annual Book of ASTM Standards, Vol. 11.02, 1995. [5] I. Ciabatti, F. Tognotti, L. Lombardi, Treatment and reuse of dyeing effluents by potassium ferrate, Desalination 250 (2010) 222 - 228. [6] E. Debik, G. Kaykioglu, A. Coban, I. Koyuncu, Reuse of anaerobically and aerobically pre- treated textile wastewater by UF and NF membranes, Desalination 256 (2010) 174 -180. [7] F. El-Gohary, A. Tawfik, Decolourisation and COD reduction of disperse and reactive dyes wastewater using chemical-coagulation followed by sequential batch reactor (SBR) process, Desalination 249 (2009) 159 -1164. [8] Franciele Regina Furlan, Laís Graziela de Melo da Silva, Ayres Ferreira Morgado, Antônio Augusto Ulson de Souza, Selene Maria Arruda Guelli Ulson de Souza, Removal of reactive dyes from aqueous solutions using combined coagulation/flocculation and adsorption on activated carbon, Resources, Conservation and Recycling 54 (2010) 283-290.
  9. 9. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 41 [9] B.Y. Gao, Q.Y. Yue, Y. Wang, W.Z. Zhou, Colour removal from dye-containing wastewater by magnesium chloride, Journal of Environmental Management 82 (2007) 167 -172. [10] V. Golob, A. Vinder, M. Simonic, Efficiency of coagulation/flocculation method for treatment of dye bath effluents, Dyes and Pigments 67 (2005) 93 -97. [11] J.M. Gozálvez-Zafrilla, D. Sanz-Escribano, J. Lora-García, M.C. León Hidalgo, Nanofiltration of secondary effluent for wastewater reuse in the textile industry, Desalination 222 (2008) 272 -279. [12] T.C. Hsu, C.S. Chiang, Activated sludge treatment of dispersed dye factory wastewater, Journal of Environmental Science and Health 32 (1997) 1921- 1932. [13] H. Huang, K. Schwab, J.G. Jacangelo, Pretreatment for low pressure membranes in water treatment: a review, Environmental Science and Technology 43 (2009) 3011- 3019. [14] M. Jekel, Wastewater Treatment in the Textile Industry. In: Treatment of Wastewaters from Textile Processing. TU Berlin, Schriftenreihe Biologische Abwasserreiigung des Sfb 193, Berlin, 1997 pp. 15 -24, [15] T.H. Kim, C. Park, J. Yang, S. Kim, Comparison of disperse and reactive dye removals by chemical coagulation and fenton oxidation, Journal of Hazardous Materials 112 (1e2), (2004) 95 -103. [16] W.J. Lau, A.F. Ismail, Polymeric nanofiltration membranes for textile dye wastewater treatment: preparation, performance evaluation, transport modelling, and fouling control- a review, Desalination 245 (2009) 321 -348. [17] T.O. Leiknes, The effect of coupling coagulation and flocculation with membrane filtration in water treatment: a review, Journal of Environmental Sciences 21 (1) (2009) 8 -12. [18] A. Pala, E. Tokat, Colour removal from cotton textile industry wastewater in an activated sludge system with various additives, Water Research 36 (11) (2002) 2920 -2925. [19] C. Phalakornkule, S. Polgumhang, W. Tongdaung, B. Karakat, T. Nuyut, Electrocoagulation of blue reactive, red disperse and mixed dyes, and application in treating textile effluent, Journal of Environmental Management 91 (2010) 918 -926. [20] K. Ranganathan, S. Jeyapaul, D.C. Sharma, Assessment of water pollution in different bleaching based paper manufacturing and textile dyeing industries in India, Environmental Monitoring and Assessment 134 (2007) 363 -372. [21] A.K. Verma, R.R. Dash, P. Bhunia, A review on chemical coagulation/flocculation technologies for removal of colour from textile wastewaters, Journal of Environmental Management, 93 (2012) 154-168. [22] J.M. Sieliechi, R. Kamga and G. Joseph Kayem, “Coagulation-Settling of Natural Organic Matter From Soft Tropical Water Using Aluminium and Iron(Iii) Sulphate”, International Journal of Advanced Research in Engineering & Technology (IJARET), Volume 4, Issue 4, 2013, pp. 118 - 133, ISSN Print: 0976-6480, ISSN Online: 0976-6499. [23] R Radhakrishanan and A Praveen, “Sustainability Perceptions on Wastewater Treatment Operations in Urban Areas of Developing World”, International Journal of Civil Engineering & Technology (IJCIET), Volume 3, Issue 1, 2012, pp. 45 - 61, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. [24] Dr.S.A.Halkude,And C.P.Pise, “Factors Affecting the Coagulation of Turbid Water With Blend Coagulant Moringa Oleifera & Alum”, International Journal of Advanced Research in Engineering & Technology (IJARET), Volume 4, Issue 4, 2013, pp. 181 - 190, ISSN Print: 0976-6480, ISSN Online: 0976-6499. [25] C. P. Pise and Dr. S. A. Halkude, “Blend of Natural and Chemical Coagulant for Removal of Turbidity in Water”, International Journal of Civil Engineering & Technology (IJCIET), Volume 3, Issue 2, 2012, pp. 188 - 197, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316.

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