INTRODUCTION:

Carpet industry in India, is one of the oldest and the most popular industries. India has an ancient heritage of carpet weaving, a craft that has asserted skill and expertise from lands as diverse as Persia, China and Afghanistan. However this art is no longer a trade, it is still isolated in the villages or towns. Along time this craft has evolved spreading its wings not only at the domestic front, but also in the international markets. Mughals brought the carpet weaving to India, and then learned magic of colors and weaves and more aesthetic touch was started to appear in Indian carpets.

Carpet industry in India, flourished more in north and western parts of the country. Major centers of carpet industry are Kashmir, Jaipur, Agra and Bhadohi-Mirzapur. Hand tufted carpets gained importance in the last few decades.

Major operations performed in Textile and carpet processing industries are designing, scouring, mercerizing, bleaching, neutralizing, dyeing, printing and finishing. These industries generate a variety of wastes i.e. liquid effluents, air emissions and solid wastes. However liquid effluents are of utmost concern because of its high volume and polluting potential. Quality and nature of waste generated depends on the fabric being processed, chemicals used, technology employed and operating practices. Disposal of untreated textile waste water is a serious threat to the environment. It accounts for 15-20% of total waste water in the country (Gopal 1994). The physico-chemical properties of soil of agricultural region and the water used for irrigation in sanganer area of Jaipur were also reported by Joshi and Kumar (2011) and the effect of physico-chemical properties of Jalmahal Lake water and some chemicals on different algae is also reported by Kumar and Singh (2009); Kumar et al.(2011) and Kulshreshtha et al.(2012).

Dyes are the most visible pollutant in the wastewater. About 3500 dyes are in practical use (Goyal et al. 2009). In aquatic systems, the dyes undergo chemical reactions and the variations in their chemical structures result in the formation of new xenobiotic compounds, which may be more or less toxic than their parent compounds (Khelifi et al. 2008 and Patil et al. 2008).

Beside dyes, the wastewater contains acid/alkali, common salt (NaCl), heavy metals, Sulphide, Chlorine and mineral oils. These wastewaters are extremely toxic to aquatic fauna and flora, crop plants and human beings.

Textiles industry waste water is characterized primarily by measurements of BOD, COD, colour, heavy metals; total dissolved and suspended solids (Demmin 1988). Dyeing and printing of textile has been developed with human civilization. Today, these industries are the backbone of economy in many developed and developing countries. In India, it contributes to about 25% of total export earning and provides employment to almost one fourth of the total labor force (Gopal 1994 and Juwarkar et. al 1997). A considerable amount of waste water generated by dyeing and printing industries have a strong color, a large amount of suspended solids, a highly fluctuating pH, salts, heavy metals, sulphides, chlorine, temperature and COD concentration (Gurnham 1965).

The present study covers the Namda or felted woolen carpet manufacturing processing in Tonk, during and after which, the carpet dyeing is applied. A lot of effluent is generated in the process, which is then allowed to drain towards the sinks of the local area, and affects the fauna and flora of Tonk. Out of the four sites selected in the present study, region 1, 2, 3 are located in the old city and the fourth is operating in RIICO industrial area, at outskirts of the city. During namda preparation process, especially in the dyeing process, a lot of waste water is generated. It is drained through local drainage system of the area and alters the microbial population of the reservoir in which the effluent is finally discharged. Therefore aim of the study was to carry out a detailed physico-chemical analysis of the effluents of four selected active carpet manufacturing units along with their remedial measures.

Study area:

The study on Biochemical analysis of the effluent of woolen carpet (Namada) industry was conducted at Tonk which is located in north-eastern part of the Rajasthan state between 75°07' to 76°19' east longitude and 25°41' to 26°34' north latitude.

MATERIALS AND METHODS:

Effluents from all the industries were collected in dry, sterile, properly caped polypropylene bottles in the year 2007. Temperature and pH were recorded on the field along with color and odour of the effluents. Samples were collected in cleaned acid washed plastic bottles and sterilized plastic bags and stored at 4°C. The samples were brought to laboratory for further physicochemical and biological analysis.

The collected samples have been analyzed to determine their physico-chemical characteristics i.e. Biological Oxygen demand, Chemical Oxygen Demand, Total Dissolved Solids, Acidity, Hardness, Chloride, Calcium, Magnesium and Nitrate. Physicochemical parameters of samples were done by standard methods (APHA 1985).

Observations and Results:

Physicochemical characters of carpet effluents:

The color of the effluent of Patni brothers, (effluent-1) was brown while the color of effluent of Riico industrial area was dark red (effluent-2), effluent of A.N. manufacturers (effluent-3) was brownish in color and the last effluent, of old bus stand, (effluent-4) showed grayish-black color. (Table 1)

As far as odor is concerned, all the effluents had fishy smell except that of Riico industrial area, (effluent-2) that had pungent smell.

Temperature of the samples ranged between 28⁰C—52⁰C, where the effluent-2 was the warmest (52⁰C) and the effluent-3 was the coolest one (28⁰C).Temperature of effluent-1 and effluent 4 were 40⁰C and 45⁰C respectively.

All the effluents were of acidic nature, the pH value ranged 3.4 – 4.3, out of this, the most acidic was effluent-2 and least acidic was effluent-1. Effluent-2 and effluent-3 displayed intermediate values of pH 3.4 and 3.8 respectively.

BOD (Biological Oxygen Demand) is a parameter, that indicates microbial load present in the effluent, and BOD range was 290 – 850 mg l^—1 in all the analyzed effluents. Effluent-2 had maximum BOD, 850 mg / l followed by effluent 3,553 mg / l, and effluent 4, 332 mg / l and the least values were for effluent 1, (290 mg / l).

Carbon Oxygen Demand is the oxygen needed to oxidize the organic compounds present in the effluent. The COD of all four samples ranged between 1043 – 1889 mg / l^—1 in which the effluent 2 showed the highest COD value, 1889 mg / l, followed by effluent 3,1730 mg/l, in the effluent 4, COD value–1125 mg / l and the lowest value was for effluent 1, (1043 mg / l).

Table 1: Physico-chemical analysis of the carpet effluents

S. No.	Physico-chemical character	Effluents from different industries
S. No.	Physico-chemical character	Effluent 1	Effluent 2	Effluent 3	Effluent 4
1.	Colour	Brown	Dark Red	Brown	Grey-Black
2.	Odour	Fishy	Pungent	Fishy	Fishy
3.	Temperature (ºC)	40	52	28	45
4.	pH	4.3	3.4	3.8	4.1
5.	BOD (mg/L)	290	850	553	332
6.	COD (mg/L)	1043	1889	1730	1125
7.	TDS (mg/L)	1005	1472	1231	1017
8.	Conductivity(µmho/cm)	1796	2209	1811	1252
9.	Acidity (mg/L)	404	348	371	390
10.	Chloride (mg/L)	1995	2210	2118	2017
11.	Hardness (mg/L)	3210	3550	3229	2821
12.	Ca (mg/L)	1750	1810	1981	1497
13.	Mg (mg/L)	1460	1740	1248	1324
14.	NO₃^-(mg/L)	123	245	212	342

Total Dissolved solids (TDS) in the effluent are an indicator of the degree of pollution in a water sample, the TDS ranged between 1005 mg / l to 1472 mg / l. The highest TDS value was for effluent 2 i.e. 1472 mg / l followed by effluent 3, i.e. 1231 mg/l while in the effluent 4, TDS value was 1017 mg/l and in effluent 1, 1005 mg/l respectively.

The conductivity or electrical conductivity (EC) indicates the presence of various inorganic ions in the effluent. It was found in a range between 1252 – 2209µ mho/cm. Where it was maximum in effluent 2 (2209 µ mho/cm) followed by effluent 3, (1811 µ mho/cm), effluent 1(1796 µ mho/cm) and effluent 4, i.e. 1017 µ mho/cm.

The effluents were highly acidic in nature; therefore their acidity is analyzed in the place of alkalinity (Alkalinity is

0.0 mg/l). The Acidity of all the effluents ranged from 371 mg/l – 404 mg/l, in which effluent 1 had the maximum

404 mg/l, followed by effluent 4, i.e. 390 mg/l and the values for effluent 3 and effluent 2 were 371 mg/l, 348 mg/l respectively.

Chloride (Cl^-) ion concentration was in the range of 1995 mg/l – 2210 mg/l, in which the effluent 2 had the maximum 2210 mg/l followed by effluent 3 and effluent 4, i.e. 2118 mg/l and 2017 mg/l respectively and the minimum was for effluent 1, i.e. 1995 mg/l.

Hardness of the water is in the form of total hardness. The total hardness varied from 2821 mg/l to 3550 mg/l in which the effluent 2 had the maximum hardness of 3550 mg/l (Ca⁺⁺ hardness = 1810 mg/l and Mg⁺⁺ hardness = 1740 mg/l) followed by 3229 mg/l by effluent-3 (Ca⁺⁺ hardness = 1981 mg/l and Mg⁺⁺ hardness = 1248 mg/l), then 3210 mg/l by effluent-1 (Ca⁺⁺ hardness = 1750 mg/l and Mg⁺⁺ hardness = 1460 mg/l), The least value was for effluent 4,2821 mg/l (Ca⁺⁺ hardness = 1497 mg/l and Mg⁺⁺ hardness = 1342 mg/l).

Nitrate content in the collected samples ranged between 123 mg/l – 342 mg/l in which the maximum value was for effluent-4, 342 mg/l, followed by effluent-2 and effluent-3, 245 mg/l and 212 mg/l respectively. The least values were for effluent-1, i.e. 123 mg/l.

DISCUSSION:

Physicochemical parameters of the selected four sites of the carpet effluent exhibited a slight or moderate variation between the parameters tested upon them. Color of the carpet effluents ranged from dark reddish to brown and blackish; which ultimately depends upon the type and color of the carpet dyes used and utilized. The process of adding color to the fiber requires large volume of water not only in the dyeing process but also during the rinsing step; the process of dyeing involves the use of salts, metals, surfactants, organic processing assistants, sulphide and formaldehyde. There are more than 8,000 products associated with the dyeing process and over 1,000,00 commercially available dyes exist with over 7 × 10⁵ metric tons of dyestuff produced annually (Chagas and Durrant 2001). All the effluents displayed a fishy to pungent level of odor; earlier reports also indicate the foul smelling (pungent) of textile effluent (Jayan et al. 2011).

All the effluents displayed a pH range between 3.4 – 4.3 (acidic range) and a temperature range between 28⁰C– 52⁰C. A display of acidic range of carpet effluent is a result of addition of acids like HCl and H₂SO₄ during the dyeing processes. Unlike the unusual acidic range of carpet effluents, the textile effluents have a pH range of 8 – 14 (Nosheen et al. 2010), 7 – 9.0 (Alkdasi et al. 2004), 6.5 – 9 (Khan et al. 2009). This alkaline pH reported to be due to excessive use of chemical agents like NaOH, H₂O₂, detergents and anionic stabilizers during the bleaching process which is not practicised during carpet dyeing process, so the exclusion of this step can be attributed to the unusual acidic pH of the carpet effluent (Wood and Kellogg 1988). Acidity of the carpet effluents ranged in between 348-404 mg/l, these high values are due to the addition of acids like HCl and H₂SO₄, during the carpet dyeing. Acid is among the major pollutants of textile waste water (Dae –Hee et al. 1999).

The BOD values of carpet effluents were fairly high i.e. lying in the range of 290-850 mg/l, as these high values of BOD clearly indicate the low amount of available (biologically available) dissolved oxygen for the utilization of organic matter (complex organic matter) by the microbes, so it actually describes the pollution strength of the waste waters or effluent. Because of this high BOD, the untreated textile waste water can cause rapid depletion of dissolved oxygen, if it is directly discharged into the surface water sources (Patel and Vashi 2010).

The effluents also display a high level of COD (mg/l), i.e. 1043 – 1889 mg/l, and the effluents with high levels of COD are toxic to biological life (Metcelf and Eddy 1991), moreover high BOD and COD produce unaesthetic color, endanger water supplies and decrease recreational value of water ways.

The effluents have a small amount of dye and a high value of TDS (mg/l) i.e. total dissolved solids, ranging from 1012 – 1472 mg/l. High TDS values are one of the major sources of sediments, which reduce the light penetration into water and ultimately decrease the photosynthesis (Nosheen et al. 2000). The decrease in photosynthetic rate reduces the DO level of waste water, which results in decreased purification of waste water by micro-organisms (Tyagi and Mehra 1990).

The conductivity (EC) of the effluent ranged between the values of 1.252 – 2.268, mmhos/cm, which is attributed to the presence of various ions in the effluent. These values are in accordance with the findings of Jolly and Islam (2009) who also reported the high values of EC in the untreated effluent (1.81mS cm^-1).

The EC is total parameter for dissociated and dissolved substances and depends upon concentration and degree of dissociation of ions as well as the temperature and mitigation of ions in the electric field, though it does not give idea about type of ions present (Rump and Krist 1992). In another study the EC values of textile waste water decreased after the treatment with selected fungal species (Ramamurthy et al. 2011).Therefore EC is not a static parameter and it changes with an increase or decrease of ions in the waste water.

The chloride ion concentration ranged between 1995-2210 mg/l, which are alarmingly high values of chloride ion content in the effluents. High chloride ion contents are harmful for metallic pipes as well as for agricultural crops if such wastes containing high chlorides are used for irrigation purposes. Moreover high chloride contents also kill some microbes, which are important in food chains of aquatic life (Kumar 1989).Chloride ions become more toxic when they combine with other toxic substances such as cyanides, phenols and ammonia (U.S. EPA 1976). Dyeing processes require large amount of salt, so the concentration of salt in dye wastewaters are always high. Textile samples may have as high as 15% w/v chloride ions.

The effluents also had a high range of total hardness, i.e. between 2845-3550 mg/l, likewise the Ca hardness also ranged high, i.e. between 1438-2110 mg/l. Magnesium hardness ranged between 1340-1460 mg/l.

Hardness in textile effluents is due to presence of divalent metallic cations like Ca⁺², Mg⁺², Sr⁺² and Fe⁺² (Abbasi 1998). Hard water has high concentrations of Ca²⁺and Mg²⁺ ions. Hardness is reported in terms of calcium carbonate and in mg/l. Hard water is generally not harmful to one's health but can pose serious problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling towers and other equipment that handles water. Hardness in water is defined as concentration of multivalent cations such as Ca²⁺and Mg²⁺ ions .Calcium and magnesium carbonates tend to be deposited as off- white solids on the surfaces of pipes and the surfaces of heat exchangers. The term total hardness is used to describe the combination of calcium and magnesium hardness. However, hardness is usually quoted in terms of CaCO₃because this is the most common cause of scaling (Sivasubramanian et al. 2012).

Hardness is a very important factor in dyeing process, as most of the dyes get precipitated in the presence of Ca²⁺and Mg²⁺ ions (Hussain et al.2004).

Nitrate in the effluent ranged from 123-342 mg/l. Some industrial wastewaters contain high concentration of nitrogen which may exist in the forms of ammonia, nitrate (v), nitrite (iii) and organic nitrogen (Priestly 1991). It is widely acknowledged that nitrogen in wastewater has become one of the major pollutants for our water resources. Environmental legislation requires removal of nitrogen from wastewater before being discharged (Zhiguo et al. 2000). Nitrogen can pose serious public health threat when present in drinking water above certain concentrations (Ohioma et al. 2009). Nitrogen is commonly found in oxic water as trioxonitrate (v), that is NO₃- The nitrate (v) ion, is not dangerous as such. It is reduced to the highly toxic dioxonitrate (iii), that is, NO₂ by certain bacteria at suboxic conditions commonly found in the intestinal tract. Nitrate (iii) causes the disease known as methemoglobinemia in infants (Ademoroti 1996).

REFERENCES:

1. Abbasi, S.A., 1998. Water Quality Sampling and Analysis. Discovery publishing House 4831/24, Ansari Road, Prahald Street. Daryaganj, New Delhi,110002 (India).

2. Ademoroti, C.M.A.1996. Standard methods for water and effluents Analysis.foludex press Ltd., Ibadan.

3. Al-kdasi, A. Idris, A. Saed, K. and Guan, C.T. 2004.Treatment of textile wastewater by advanced oxidation process. Global Nest: the Int. J. 6: 222-230.

4. APHA, AWWA and WPCF, 1985. Standard Methods for the examination of water and waste water.16^th edition.

5. Chagas, E.P. and Durrant L.R. 2001. Decolourization of azo dyes by Phanerochaete chrysosporium and Pleurotus sajor-caju. Enzyme Microb. Technol. 29: 473-477.

6. Dae-Hee, A. Won-Seok,C. and Tai-I, Y. 1999. Dyestuff wastewater treatment using chemical oxidation, physical adsorption and fixed bed biofilm process, Process Biochemistry. 34: 429–439.

7. Demmin,T.R. and Uhrich,K.D.1988. Improving carpet wastewater treatment.American dyestuff Reporter. June: 13.

8. Gopal, B.1994. Conservation of inland waters in India, An overview, Verh. Internat.Verein Limnol. 25: 24-94.

9. Goyal, S. Sharma, G. and Bhardwaj, K.K. 2009. Decolorization of synthetic dye (Methyl Red) waste water using constructed wetlands having upflow and downflow loading formate. Rasayan J. chem. 2 : 329-331.

10. Gurnham, C.F.1965.Industrial waste control.Academic press, New York.

11. Hussain,J. Hussain, I. and Arif, M. 2004.Characterization of textile waste water.Jr. of Industrial pollution Control.20:137-144.

12. Jayan, A. M. Maragatham, R. N. And Saravanan, J. 2011. Decolorization and physico chemical analysis of textile azo dye by Bacillus. International Journal on Applied Bioengineering. 5:35-39.

13. Jolly, Y. N. and Islam, A. 2009.Characterization of dye industry effluent and assessment of its suitability for irrigation purpose. Journal of Bangladesh Academy of Sciences. 33: 99-106.

14. Joshi N. and Kumar A. 2011. Physico-chemical Analysis of Soil and Industrial Effluents of Sanganer Region of Jaipur Rajasthan. Res. J. Agricul. Sci., 2(2): 354-356.

15. Juwarkar,A.Padole,L.M.and Oke,B.H.1997. HRTS effluent treatment. The Indian Textile Journal.14.

16. Khan, M.S. Ahmed, S. Evans, A. E. V. and Chadwick, M. 2009. Methodology for Performance Analysis of Textile Effluent Treatment Plants in Bangladesh. Chemical Engineering Research Bulletin. 13: 61-66.

17. Khelifi, Gannoun, E. H. Touhami, Y. Bouallagui, H. and Hamdi, M.2008. Aerobic decolorization of the indigo dye-containing textile wastewater using continuous combined bioreactors, Journal of Hazardous Materials. 152:683–689.

18. Kulshreshtha J., Kumar M. and Singh G. P. 2012 Impact of different culture conditions on Growth and pigment contents of Anacystis nidulans. Indian Res. J. Agricul. Sci. 82 (9): 794–9.

19. Kumar M, Kulshreshtha J. and Singh G. P. 2011 Growth and pigment profile of Spirulina platensis isolated from Rajasthan, India. Res. J. Agric. Sci. 2(1): 83-86.

20. Kumar M. and Singh G. P. 2009 Effect of Ethyl methane sulphonate on growth and pigments of Spirulina platensis. Indian Hydrobiology. 12(1): 39-47.

21. Kumar, A. 1989. Environmental Chemistry. Pages: 261–4. Wiley Eastern Limited, New Delhi.

22. Metcelf and Eddy Inc., 1991.McGraw Hill Publishing Company, McGraw Hill International Editions, Singapore, 3rd Edn.

23. Nosheen, S. Nawaz, R. Arshad, M. and Jamil, A. 2010. Accelerated Biodecolorization of Reactive Dyes with Added Nitrogen and Carbon Sources. Int. J. Agric. Biol. 12: 426–430.

24. Ohioma, A. I. Luke, N. O. and Amraibure, O. 2009. Studies on the pollution potential of wastewater from textile processing factories in Kaduna, Nigeria. Journal of Toxicology and Environmental Health Sciences.1 : 034-037.

25. Patel, H. and Vashi, R.T. 2010. Treatment of Textile Wastewater by Adsorption and Coagulation. E-Journal of Chemistry. 7:1468-1476.

26. Patil, P.S. Shedbalkar, U.U. Kalyani, D.C.and Jadhav, J.P.2008. Biodegradation of Reactive Blue 59 by isolated bacterial consortium PMB11. J Ind Microbiol Biotechnol. 35:1181–1190

27. Priestly, A.T.1991. Report on Sewage Sludge Treatment and Disposal Environmental Programs and Research Needs from an Australian Perspective. CSIRO, Division of chemicals and Polymers: 1 –44.

28. Ramamurthy, N. Balasaraswathy, S. and Sivasakthivelan, P. 2011. Biodegradation and physicochemical changes of textile effluent by various fungal species. Romanian J. Biophys. 21: 113–123.

29. Rump, H.H. and Krist, K. 1992. Laboratory manual for examination of water, wastewater and soil. 2nd ed., VCH P0-blishers, New York.

30. Sivasubramanian, V. Subramanian, V. V. Muthukumaran, M. and Murali, R. 2012. Algal technology for effective reduction of total hardness in wastewater and industrial effluents. Phykos.42 : 51– 58.

31. Tyagi, O.D. and Mehra, M. 1990. A textbook of environmental chemistry. Anmol Publications, New Delhi, India.

32. U.S. Environmental Protection Agency (EPA),1976. Drinking Water Regulations and Health Advisories, EPA 822-R -94-001.

33. Wood, W.A. and Kellogg, S.T. (eds.) 1988. Biomass. In: Methods in Enzymology, Academic Press, Inc. San Diego, CA. 161 part B.

34. Zhiguo, Y. Herwig, B. James, L. and Willy, V. 2000. Reducing the Size of Nitrogen Removal Activated Sludge Plant by Shorting the Retention Time of Inert Solid via Sludge Storage. Wat. Res. 34 : 611- 619.

Received on 15.12.2012 Accepted on 02.02.2013

Research J. Science and Tech 5(2): April- June, 2013 page 245-249