Dyers submit fresh proposals for achieving zero liquid discharge

A year after the Madras High Court directed the closure of over 720 dyeing units in Tirupur, the dyers have submitted fresh proposals with the promise of improved technology for achieving zero liquid discharge to be functional again.

“The closed dyeing units have submitted proposals for achieving zero discharge with new and proven techniques. Once all the proposals are in, the papers will be verified with assistance from professors of Indian Institute of Technology-Madras and Anna University-Chennai, over the next few months,” said an official at the Tamil Nadu Pollution Control Board (TNPCB).

If the proposals are found convincing, the dyeing units would be asked to submit a detailed project report and then allowed to operate in a phased manner, initially at 30 per cent of capacity and then at 50 per cent, to monitor if the zero liquid discharge as ordered by the High Court was adhered to, the official said. According to industry sources, the dyers had already invested Rs.800 crore on treating waste water and were paying huge sums as interest but could not achieve zero discharge. The new proposals are based on the governments' grant of Rs.200 crore for the dyers, official sources said.

TNPCB officials in the know said the common effluent treatment plants (CETPS), to which over 500 dyeing units were linked, were able to treat 85 per cent of waste water but were struggling for want of technology to achieve zero liquid discharge.

“Now, the plan is to try out nano-filtration and multi-effect evaporation to achieve zero liquid discharge in three CETPs,” said a senior TNPCB official.

According to a Central Pollution Control Board (CPCB) report on waste water treatment, nano-filtration could be positioned between reverse osmosis (RO) and ultra-filtration. Nano-filtration can be operated on lower pressure than reverse osmosis and as such treatment cost is lower than for RO. For zero discharge, Tirupur dyeing industry has to look at a multi-effect evaporator instead of the mechanical vapour recompression used earlier, the official said.

In fact, the CPCB had specifically suggested nano-filtration and multi-effect evaporator as technologies to achieve zero discharge in Tirupur dyeing industry way back in 2005. However, the dyers refused to embrace the technology but came up with a marine discharge proposal. “We have rejected the marine discharge proposal asking the dyers to look at technological options to be functional again,” said a senior official.

Before the High Court order, the Noyyal river and ground water survey in Tirupur showed that the TDS (Totally Dissolved Solid) had grossly contaminated the water with levels ranging above 5,000 mg/l (milligram per litre) as against the standard 2,100 mg/l which was a gross violation of norms.

The TNPCB, after a study visit to dyeing units in Gujarat, has suggested nano-filtration membranes.

HC declines interim injunction to farmer affected by Noyyal river pollution

The Madurai bench of theMadras high court, on Wednesday directed the state government to file its counter on a petition filed by a Karur-based farmer, alleging that the government's order disbursing amount of compensation to the members of Noyyal River Ayacutdars Protection Association (NAPA), alone is arbitrary. However, the court declined to grant interim injunction as sought by the petitioner.

In his petition, R Selvam, a farmer and ayacutdar of the Orathupalyam reservoir, said over 28,000 farmers were identified by the Loss of Ecology Authority (LEA), as affected by the Noyyal river water and Oruthupalayam dam, which were polluted due to effluents discharged by the dyeing units in Tirupur.

Button dyers under scanner for polluting Noyyal

The garment button dyeing industry workers of Tirupur have hit the panic button following the closure of 120 of their units in the knitwear hub over the recent weeks. These units were asked to shut shop and cease operations after the Tamil Nadu Pollution Control Board ( TNPCB) officials found that they were discharging coloured residual water mixed with dye solvents into open drains and channels of the Noyyal river.

As many as 2,000 workers directly involved with button dyeing units scattered across the city and nearby areas are in a tight spot as a result of these developments, claimed the office bearers of Small Industries Button Zippers and Accessories Lab Association (SIBLA), Tirupur. This ancillary sector dependent on the garment cluster is yet to get organised and the SIBLA is the sole registered body with over 300 units each engaging about three to five workers.

"We do not use any toxic dyes and our process is also not as mechanised and complex as garment dyeing. The officials have claimed that as per the court ruling we cannot discharge coloured effluent water into the open drains and they are sealing off the button dyeing units. Our members also observed a one day fast and have called for suspension of production till authorities take a favourable stand in the issue," said R Muthaiyyan, secretary, SIBLA, Tirupur.

Most of the button dyeing units function out of rented sheds and congested areas in residential areas in the city. They procure finished plastic buttons from wholesale agents in Delhi, Chennai and Hyderabad and stockpile them in Tirupur. Based on the orders received from the garment units in Tirupur, these buttons are immersed in polyester and nylon dye solutions after they are heated in big open containers. After the buttons are dyed in the desired shades then it is taken out of the solution and dried to be stitched on to the garment. "Most of the units do let out the remaining solution into open drains but the quantity and the dissolved salt levels are minimal when compared to the garment dyeing and bleaching units and hence the pollution control board officials should not use the same yardstick against us," Muthaiyyan said.

However, R Kannan, district environmental engineer, Tamil Nadu State Pollution Control Board (TNPCB), Tirupur, told TOI that the button dyeing units should also comply with the existing norms and cannot discharge coloured solvents into open drains and the river channels. He also added that these solutions contain chloride and sulphate salts which are not supposed to be openly discharged into the open. "We have received a petition from the SIBLA requesting us not to take action against the button dyeing units. So far 120 units have been sealed for letting out coloured effluents," Kannan said.

It is also being mooted that the button dyeing units should get organised and set up a common base in the garment cluster near the Common Effluent Treatment Plants so that they could ensure they are follow the zero effluent discharge norms devised as per the court directive. However, a majority of the units might face practical difficulties in adopting this method as they are extremely small scale in nature with minimum workforce and mechanisation.