Abstract: Tannery industry processes are among the most environmentally polluting industrial processes because they produce different colored wastewater that heavily damages the environment and surrounding places. The experiment was conducted with different treatments of tannery effluent (TN) with coir pith (CP) and Nava rasa karaisal (NRK) and analyzed the physical and chemical parameters. There are fifty-one parameters like pH, salinity, Na, Pb, Hg, Zn, etc. which were analyzed and the results showed that the chemical absorption of treated tannery effluent was found better when compared with the other treatments. Hence, the present investigation revealed that the solid waste combination of (Tannery effluent + Coir pith + Nava Rasa Karaisal) can be used as organic fertilizers for plant growth and developments.
Keywords: Tannery effluent, Coir pith, NRK, Biofertilizer, BOD, COD
Introduction The tannery industries are the backbone of the leather industries and the colored wastewater generated from the various processing units is due to bleaching, mercerizing, dyeing, printing, and packing which require a large number of synthetic chemicals. Further, the effluent from the tannery industries is usually discharged with all types of pollutants into the sewage system or neighboring land causing serious environmental problems (Murali et al., 2013). The leather industry is one of the traditional and oldest industries in India and one of the leading foreign exchange earners for the country. But the industry is plagued by heavy pollution stress on the environment, thus negating some of the other societal benefits the industry has merited. Production of leather, leather goods, boards, and fur produces numerous by-products like solid waste and high amounts of wastewater containing different loads of pollutants and toxic chemicals.
Thamizhiniyan et al. (2009) earlier reported that water is the main source for industries to dispose of waste materials. It is found that almost all rivers are polluted in most of the stretches by some industries. Toxic heavy metals, which are of concern, like chromium (Cr), lead (Pb), zinc (Zn), arsenic (As), copper (Cu), nickel (Ni), cobalt (Co), cadmium (Cd) and mercury (Hg), are not biodegradable. So they tend to accumulate in the living organisms and lead to different types of diseases and disorders which finally threaten human life (Monachese et al., 2012). As a solution to this problem, some methods like reverse osmosis, ion exchange, membrane filtration, and electrodialysis are used effectively for removing these metals. But they are costly and generate concentrated wastes that require subsequent treatment for disposal. Biological removal may provide a suitable means for the treatment of wastewater (Lovely and Coates 1997 and Rittmann et al., 2004). The cyanobacteria showed enormous potential in wastewater and industrial effluent treatment, bioremediation of aquatic and terrestrial habitats, chemical industries, bio-fertilizers, (Malliga et al., 1996, Abraham et al., 2002, Malliga and Viswajith, 2005 & 2007, Chandrasekar et al., 2008, Pazhanivel et al., 2011, Bhuvaneshwari et al., 2011, Subramaniyan and Malliga, 2011, Subramaniyan et al., 2012, Durai Raju and Malliga, 2013, Shanmugapriya and Malliga, 2013, Lakshmi and Malliga, 2014, Nivetha et al., 2014, Lakshmi et al., 2015 and Jenny and Malliga, 2018), feed, etc., (Cairns and Dickson, 1971 and Kulasooriya, 2011).
Coir pith is the by-product of coir yarn industries which constitute about 70percent husk. As coir pith has a high content of lignin and it takes decades to decompose, it causes environmental hazards because of its disposal problems (Krishnamoorthy et al., 2012). The water holding capacity of coir pith is enormous which a boost to the growth of cyanobacteria was. The non-nitrogen fixing cyanobacteria which enriched the phosphorus and potassium contents in the soil also played a major role in food, feed, and medicine. Christopher et al. (2007) concluded that the coir pith based cyanobacterial biofertilizer could be an effective alternative or combination with chemical fertilizer. The recent research shows that coir pith can be partially decomposed through the action of cyanobacteria and can be used as a biofertilizer for all varieties of food crops (Silambuselvi et al., 2014, Durai Raju and Malliga, 2013 and Jenny and Malliga, 2016). Nava Rasa Karaisal is a concoction prepared by the mixing of nine products and used in traditional rituals. It enriches the soil and provides the entire nutrient requirements for the growth of the plant. Physiochemical and biological properties of Nava Rasa Karaisal revealed that they possess almost all the macronutrients, micronutrients and growth hormones required for crop growth. Nava Rasa Karaisal contains rich sources of nitrogen and valuable microorganisms which naturally enhances soil fertility and also Kalaibharathi et al. (2019) reported that the Nava rasa karaisal enriches the soil, plant and provides all the nutrients required for the plant growth. NRK is also called as microbial consortia used in treatment for seed and planting material. In this current research, five treatments in which physiochemical characterizations were analyzed to find out the reduction of different chemicals and heavy metals.
Materials and Methods
The effluents were collected from the tannery industry at Sempattu Unit, Tiruchirappalli, Tamil Nadu, India, and coir pith was collected from coir industries near Samayapuram, Tiruchirappalli, Tamil Nadu, India. The collected effluent was mixed with NRK, CP separately and in combinations and the effluents were taken for the following physical and chemical parameters like Colour (IS: 2720 part I (1987), pH (APHA 1989), TDS (IS: 3025 Part 16: 1984), TSS (IS: 3025 Part 17: 1984), Alkalinity as CaCO3 (IS: 3025 Part 23: 1986), Hardness as CaCO3(IS: 3025 Part 21: 2009), Chloride (APHA, 1989), Nitrite (APHA, 1995), Nitrate (APHA 1976), Salinity (APHA 22nd Ed, 2012), Potassium (US EPA 3050 B, 1996), Biological Oxygen Demand (BOD) (IS: 3025 Part 58: 2006, RA 2012), Chemical Oxygen Demand (COD) (IS: 3025 Part 44: 1993 RA 2009), Calcium and Magnesium (Govindaraju et al., 2001), Zinc (US EPA 3050 B, 1996) and Selenium (IS: 3025 Part 56: 2003) which were analyzed through the standard techniques (Table 1 & Table 2).
Result and Discussion
Bio-fertilizers are eco-friendly and supply the nutrient inputs of microbial origin for plant growth and developments. Organic fertilizers and manure can increase the quality and improve the yield paving the way for sustainable agriculture. In the present investigation, physiochemical parameters were analyzed for the collected untreated tannery effluent and treated tannery effluent with coir pith and Nava Rasa Karaisal. The tannery effluent exists as pale brown in color; Nava Rasa Karaisal was white with gray in color and exhibiting microbial growth; Tannery effluent with Nava rasa karaisal color was changed into very light brown and also showing the growth of microorganisms; Tannery effluent with Coir pith color was light brown and Tannery effluent with Coir pith and Nava Rasa Karaisal after treatment the color was changed from pale brown to dark brown in color because of microbial effects (Plate 1; Table 1 &Table 2,). Supporting evidence showed that untreated effluent color was brownish-black while treatment with sorghum the color changed into muddy grey in color (Gark and Kaushik, 2009) and untreated industrial effluent was grey in color and after treatment with Pseudomonas sp. turn in yellow color on the observation of 15th day (Susithra et al., 2009). The untreated tannery effluent color changed after treatment from dark brown to pale brown (Murali et al., 2013). Initially tannery effluent color was brown and after treated by a bacterial consortium (Bacillus sp., Pseudomonas sp. and Micrococcus sp.) the color was changed into brown to light brown on 72 hrs (Mythili and Karthikeyan, 2011). The color of leather industrial effluent is black before treatment but, after the degradation with the native fungus, Aspergillus niger and non- native fungus Aspergillus flavus the color changed into almost colorless (Noorjahan, 2014). The turbidity of tannery effluent was not changed after treatment with the TN with CP and NRK (Table 1). The initial pH of the tannery effluent was 8.87 and reduced to pH 6.73 (TN+CP+NRK) and 6.64 (TN+CP) in solid waste treatments (Table 1 & Table 2). Similarly, Mohammed Assou et al. (2014) showed that the optimization of multiple responses allowed coagulants and flocculants doses to be minimized while maximizing the percentage of turbidity 97percent removal.
James Jeya Josepine. A. 1 , Jenifer. G. P.2 and Malliga. P.3 1&2Department of Marine Biotechnology, 3Professor & Head, Department of Marine Biotechnology, Bharathidasan University, Tiruchirappalli, India Email: firstname.lastname@example.org