STUDY ON TIRUPPUR CETPs DISCHARGE AND THEIR IMPACT ON NOYYAL RIVER AND ORATHUPALAYAM DAM, TAMIL NADU (INDIA)

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1 STUDY ON TIRUPPUR CETPs DISCHARGE AND THEIR IMPACT ON NOYYAL RIVER AND ORATHUPALAYAM DAM, TAMIL NADU (INDIA) A. Samuel Rajkumar *1 and S. Nagan 2 1. Tamil Nadu Pollution Control Board, Chennai (INDIA) 2. Depatment of Civil Engineering, Thiagarajar College of Engineering, Madurai (INDIA) Received November 14, 21 Accepted February 24, 28 ABSTRACT Tiruppur town is located on the bank of Noyyal river, Tamil Nadu, India. Noyyal is a tributary of river Cauvery. There 729 bleaching and dying units are in operation in Tiruppur area. These units generate 96.1 million litres per day (MLD) of wastewater. Initially, they discharged untreated effluent into the river. In year 1997, after the Tamil Nadu Pollution Control Board (TNPCB) directions they installed 8 Common Effluent Treatment Plants (CETP) and individual effluent treatment plants (IETP) consisting of physical, chemical and biological treatment process. Even then, the treated effluent from the CETPs and IETPs did not meet the Total Dissolved Solid (TDS) and chloride standards. The discharge of high TDS and chloride effluent into Noyyal river had significantly affected the river water quality, groundwater quality as well as the Orathupalayam dam which is constructed across Noyyal river at 32 km down stream of Tiruppur. In year 26, the honorable High Court of Madras and TNPCB directed the bleaching and dyeing units to install Zero Liquid Discharge (ZLD) plant consisting of RO plant and reject management system. At present there are 17 CETPs with ZLD plant are in operation. The treated effluent is reused by the member units. The RO reject is concentrated in Multiple Effect Evaporator (MEE) / Mechanical Vacuum Re-compressor (MVR) and then solar evaporated. Thus the discharge into the river is now stopped. However the damage caused to the groundwater and soil in the river basin is yet to be restored. Key Words : Tiruppur discharge, Noyyal river, Mechanical Vacuum Re-compressor (MVR), Zero Liquid Discharge (ZLD) plant, Multiple Effect Evaporator (MEE) INTRODUCTION Tiruppur is the head quarter of Tiruppur district. Geographically the town is at 11.7 o north latitude and 77.5 o east longitude. The town is spread over an area approximately 27 sq.km and a population of 3.5 lakhs. It is located on the bank of Noyyal river 1. It is one of the well-known places in hosiery and knitwear manufacture in international market. Tiruppur accounts for 9% of India s hosiery and knitwear export 2. The main activities in industrial sector here are ginning, weaving, knitting, bleaching, and dyeing, printing and allied works. Tiruppur has become an important textile cluster *Author for correspondence 558 in India both for overseas market and the domestic market. It has 25 knitting and stitching units, 729 dyeing and bleaching units, 3 printing units, 1 embroidery units and other 2 units catering to compacting, raising and calendaring. This town annually contributes about INR 36 crores in foreign exchange earnings to India. The dramatic improvement in Tiruppur s export market can be attr ibuted to the disbanding of gar ment manufacturing in western countries due to environmental pollution and high cost of labour. Due to low annual rainfall (~ 5 mm/year), textile wet processing industries in Tiruppur buy water through lorries from surrounding villages at a cost of around INR. 115 crores annually 3.

2 Study area The Noyyal river is a tributary of the river Cuavery. The Noyyal river originates from Velliangiri hills in the western ghats and flows through Coimbatore, Tiruppur, Erode and Karur districts traversing distance of 172 km and confluences with the river Cauvery at Kodumudi which is at 55 km down stream of Tiruppur. A dam namely Orathupalayam dam is constructed across the Noyyal r iver at about 32 km downstream of Tiruppur Town, to irrigate ayacut of 2, 2. The river has seasonal flow, mostly during the north-east monsoon period. Return flow from Lower Bhavani Project (LBP) canal also drains into the Noyyal. The river gets polluted when it passes through Tiruppur, due to discharges of 96.1 million litres per day (MLD) of coloured effluent with high total dissolved solids (TDS) in the range of 6 to 7 mg/l, by the textile belching and dyeing units in Tiruppur 4. Apart from the industrial pollution, about 3 MLD of untreated municipal wastewater find its way into the Noyyal river and makes the river as one of the most polluted rivers in the State. The groundwater in the down stream of Tiruppur and the surface water in Orathupalayam dam have become highly polluted. A line sketch of Noyyal river basin is given in Fig. 1. Fig. 1 : Location of Noyyal river basin, CETPs and river water sampling points Textile bleaching and dyeing units In Tiruppur, there are 729 bleaching and dyeing units under operation 3. They process mainly hosiery and cotton cloth. They carryout wet process activities which includes i). bleaching, ii). neutralizing, iii). washing, iv). Acid wash, vii). washing, viii). soaping, ix). hot wash, x). fixing and softening 5 (Fig. 2). The wastewater generated by bleaching and dyeing operations mainly depends on the chemicals utilized and the processes adopted. 1 kg of fabric bleaching and dyeing process generate 8 litres of trade effluent from soft flow machine process, and 15 litres from winch machine process 5 (Table 1). 559

3 Raw Fabric Bleaching Neutralizing Washing Dyeing Washing Acid wash Washing Soaping Hot wash Fixing & Softening Finished Fabric Fig. 2 : Process flow chart Table 1 : Raw effluent characteristics of the combined effluent form bleaching and dyeing process 5 Each unit discharges about 15 kilo litres per day (KLD) of effluent. In total the units in Tiruppur discharge about 96.1 MLD of effluent. After treatment it finally reaches Noyyal river. This alone makes the Noyyal as a perennial river, having otherwise been betrayed by nature. Effluent treatment plants The large and medium scale units (236 units) have provided individual effluent treatment plant (IETP). After treatment they use the treated effluent on land of irrigation in their own land. The remaining medium and small scale units (493 units) who have not adequate land and finance to provide IETP, have joined together and formed company 4. Through the company they executed 8 common effluent treatment plants (CETP) with 5% finical subsidies from Central and State Governments. 56 The treatment system generally consists of collection well, equalization tank, flash mixer, clariflocculator, aeration tank, clarifier, pressure sand filter, sludge thickener, centrifuge, and sludge drying beds. After treatment the treated effluent was discharged into river Noyyal. In this study, the performance of the CETPs and the quality of Noyyal river water, Orathupalayam dam water quality are presented. AIMS AND OBJECTIVES All the dyeing units in Tiruppur have provided treatment plant either commonly or individually. The units without treatment plant were shut down by the TNPCB. Even then complaints are being received from the farmers that the river water and the Orathupalayam dam water is polluted due

4 the dyeing units effluent discharge. In order to assess the actual field condition, this study was taken up. The aim and objective is to monitor the 7 operational CETP s outlet and at the same period to monitor the river water quality at the upstream and down stream and also to monitor the Orathupalayam dam water quality. MATERIAL AND METHODS Treated effluents samples were collected every month from the out let of 7 operational CETPs from April 28 to March 29. At the same time Noyyal river water samples were collected at three locations (i.e). Mangalam (2 km upstream of Tiruppur), Kasipalayam (5km down stream of Tiruppur) and Anaipalayam (2 km down stream of Tiruppur). Similarly at Orathupalayam dam (32 km down stream of Tiruppur) also water sample was collected in the same period. Samples were collected in 2.5 litre new plastic containers and got analyzed in TNPCB laboratory. The samples were analyzed as per the standards methods of APHA 6. The analysis was carried out for physico chemical parameters.(table 2) Chloride mg/l Fig. 3 : TDS profile of CETPs RESULTS AND DISCUSSION The report of analysis of CETPs treated effluent quality is given in Table 2. It reveals that TDS was in the range of mg/l as against permissible level of 21 mg/l 7, chlorides was in the range of mg/l as against the permissible level of 1 mg/l, BOD was in the range of 1-3 mg/l as against the permissible level of 3 mg/l, COD was in the range of mg/l as against the permissible level of 25 mg/l, % sodium was in the range of 85-98% against permissible level of 6% (on land for irrigation standards). The results are plotted in graph and given in Fig. 3 to Fig. 6 The Noyyal river water quality (Table 3) reveals that the TDS level in the upstream of Tiruppur was in the range of mg/l, down stream was in the range of mg/l as against the permissible level of 15mg/L 8. Chlorides in the upstream was in the range of mg/ L and in the down stream was in the range of mg/l as against the permissible level of 6 mg/l. BOD in the upstream was in the range of 1-48 mg/l and in the down stream 1-36 BOD mg/l Apr'8 Oct'8 Nov'8 Andipalayam Angeripalayam Kasipalayam Mannarai Chinnakarai Kunnangalpalaym Veerapandi Standard Fig. 4 : Chloride profile of CETPs Apr'8 Oct'8 Nov'8 Andipalayam Angeripalayam Kasipalayam Mannarai Chinnakarai Kunnangalpalaym Veerapandi Standard Fig. 5 : BOD profile of CETPs 561

5 COD mg/l TDS mg/l Apr'8 Oct'8 Nov'8 Apr'8 Oct'8 Nov'7 Mangalam Kasipalayam Anaipalayam Orathupalayam Dam Andipalayam Angeripalayam Kasipalayam Mannarai Chinnakarai Kunnangalpalaym Veerapandi Standard Fig. 8 : Chlordies in Noyyal river Fig. 6 : COD profile of CETPs mg/l as against the permissible level of 3 mg/l. COD in the upstream was mg/l and in the down mg/l. In the Orathupalayam dam, the TDS (Table 3) in April 8 was 7888 mg/l and it was reduced to 4256 mg/l in March 9. Chlorides were reduced from 2324mg/L to 195 mg/l. This is due continuous release of dam water without stocking and improvements in the CETP discharges 4. The results are plotted in graph and given Fig. 7 to Fig. 1. Pollution concentration in Noyyal river is low till the river reaches Tiruppur. But it increases considerably in Tiruppur area, due to textile effluent discharge, and continues up to Orathupalayam dam. Pollution concentration in the river is more in summer than TDS mg/l Apr'8 winter. The existing moderate flow in Noyyal is not sufficient for diluting the pollutants 9,1. The environmental impact on ground water, surface water, soil, fish and the natural eco-system in the Tiruppur area and in downstream area is due to Oct'8 Mangalam Kasipalayam Anaipalayam Orathupalayam Dam Nov'7 Fig. 7 : TDS in Noyyal river 562 BOD mg/l COD mg/l Apr'8 the following reasons: (a) the continuous discharge of untreated / partially treated effluent for more than 2 years has accumulated in the soil, water, etc in many locations. The Noyyal river and the land in and around the town of Tiruppur do not have the capacity to assimilate the TDS and chlorides Unless remediation measures are undertaken, the impact will continue for several Oct'8 Mangalam Kasipalayam Anaipalayam Orathupalayam Dam Apr'8 Nov'7 Fig. 9 : BOD in Noyyal river Oct'8 Nov'7 Mangalam Kasipalayam Anaipalayam Orathupalayam Dam Fig. 1 : BOD in Noyyal river

6 Table 2 : Report of analysis of CETP outlet (before discharge into Noyyal river) All parameters are in mg/l except % Sodium. Inland surface water discharge standards as per CPCB : TDS 21 mg/l, Chloride 1 mg/l, BOD 3 mg/l, COD 25 mg/l % 563

7 Table 3 : Report of Analysis of Noyyal river water and Orathupalayam dam water samples All parameters are in mg/l except % sodium, IS 2296 : 1982 standards for class C water body : TDS - 15 mg/l, chlorides - 6 mg/l, BOD 3 mg/l % sodium for irrigation 6 (max. limit) 564

8 years even after treatment measures are in place (b). the existing effluent treatment plants even when they are functioning are unable to reduce the total dissolved solids and chloride levels, resulting in continuing contamination of soil and water. The environmental impact is not only in Tiruppur (local) but in downstream areas also. CONCLUSION Noyyal river basin was polluted due to discharge of effluent by the bleaching and dyeing units. In order to protect the surface water and groundwater, TNPCB had directed all the bleaching and dyeing units in Tiruppur to provide zero liquid discharge (ZLD) plant and achieve zero discharge. Accordingly the existing 7 operational CETP member units have provided ZLD plant which consists of Reverse osmoses (RO) plant, and reject management systems (RMS). The RMS consists of multiple effect evaporator or mechanical vacuum recompressor followed by crystallizer, centrifuge and solar pan. The RO permeate and MVR condensate is reused in the dyeing process and the salt from solar pan is stored in secured land fill facility. The IETP units have also joined together and provided 1 ZLD plants. At present 17 common ZLD are in operation since January 21. Once this ZLD is operated successfully, further pollution of Noyyal river will be stopped. Tamil Nadu Government has also banned setting up of water polluting industries within 5 Km from the Noyyal River. REFERENCES 1. Environmental Cell Division, Water Resources Organization, PWD, Coimbatore, Pilot studies to restore Orathupalayam dam, (27). 2. Institute of Water Studies, PWD, Environmental impact of industrial effluent in Noyyal river basin, (22). 3. Madras school of economics, Chennai, Compensating the loss of ecosystem services due to pollution in Noyyal river basin, Tamil Nadu, India, (26). 4. TNPCB, Report on Bleaching and dyeing Industries in Tiruppur, Tamil Nadu, India, (29) Environment with people s involvement and co-ordination in India, Tiruppur, Zero discharge project report for Kuppandampalayam effluent treatment, Company (P) Ltd, (27). 6. APHA Standard method for examination of water and wastewater, 2 th Ed., Washington D.C., U.S.A., (1998). 7. Central pollution control board, Delhi, Environmental standards for ambient air, automobiles, fuels, industries and nose, (2). 8. Indian standards, tolerance limits for inland surface waters subjected to pollution, (1982). 9. Ramasamy V. and Rajagopal, Ground water quality in Tiruppur, Ind. J. Environ. Hlth. 33 (2), , (1991). 1. Senthilnathan S. and Azeez P. A., Water quality of effluents from dyeing and bleaching industry in Tiruppur, Tamil Nadu, India, J. Ind. Poll. Con., 15(1), 79-88, (1999). 11. Abbasi S. A., and Vinithan S., Water quality in and around an industrialized suburb of Pondicherry, Ind. J. Environ. Hlth., 41(4), , (1999). 12. Centre for Science and Environment, New Delhi., Report on the pollution of Bandi river by textile industries in Pali town, (27). 13. Impact of textile dyeing and printing industrial effluent on soil and ground water quality: a case study, Ind. J. Environ. Prot., 19(1), , (1999). 14. Patnaik K.N., Satyannarayana S.V., and Rout S.P., Water pollution from major industries in Paradip area: a case study, Ind. J. Environ. Hlth., 44(3), ,(22). 15. Rahmani H. R., Invesigation effects of industrial waste water of Yazd-Baf factory on soil and plants, J.Environ.Res.Develop., 2(3), , (28).