Water: no longer a cheap resource!

With thanks to Dr K S Murthy, Pidilite Industries Ltd, for reporting on this recent SDC EC event.

If there is anything in this world that has no alternative, it is water. A good thought becomes reality only when implemented. With this in mind, SDC EC organised a half-day seminar titled “Water: No more a Cheap Resource” in December 2015 in Mumbai for the benefit of the textile processing industry.

Mr Sachin Pulsay, Chairman, Mumbai Chapter welcomed everyone to the event.

Mr Pradeep Dodhia, Director, Dodhia Synthetics Ltd, and Chief Guest thanked SDC and wished the seminar success. Keynote speaker Mr Hardik Shah, Chacha Industries, said water is required for every activity and realised its importance in his processing industry. Per capita availability of water in 1947 was 6,042 cu m, which came down to 1,545 cu m in 2011 and is predicted to be 1,340 cu m by 2025. In India 55% people depend on agriculture followed by industry where the water shortage is acute. We have to save water by rain harvesting and avoiding leakage.

Mr Ramesh Agarwal, Vice President, Sales, Archroma India Private Ltd spoke on polyester dyeing and innovation. Dyeing with disperse dyes by diffusion, desorption of colour and its removal by reduction clearing (RC) for optimal fastness. The ranges are Foron RD, RDE, RDS, S and SWF. Foron RD dyes effect saving of water and energy besides increasing productivity against conventional dyes.

• Donnapal ELD concept: PEs can be dyed at pH 9 in alkaline medium wherein RC and machine cleaning (oligomer deposits) is dispensed with besides effecting brightness, saving of water, energy, time and effluent load.
• Sustainability by innovation: Entails biodegradable products with low BOD and COD values that help effluent treatment.
• Ecology and environment, economy and efficiency, one way selector, process cluster (optimise process; reduce cycle time, improve productivity and CO₂ emissions). Methodology is product selection, process shortlisting and solution selection based on eco standards, MRSL compliant, zero discharge and bio-elimination. One way calculator is for saving water, energy, time, productivity and COD elimination.
• Smart Repel Hydro Blue Magic concept: saving energy, water and electricity; Advance Denim; EarthColors; Nylosan (metal free) dyes.

Mr Pradeep Rane, General Manager, CHT India Private Ltd spoke on the innovative Four Successes Module benefiting not only the environment but saving water, time and energy diversifying discontinuous pre-treatment processes for cellulosic fibres and suitable for all machines like jet dyeing, jigger or package. The products are Blue Sign approved.

• Innovation for peroxide (activator) bleaching, booster technology combined with Comb Polymers: Vario Bleach 3E – low temperature as well as high temperature and optimised bleaching process in alkaline pH. Full white at 70^oC. Whiteness CIE 156; Base white 82 and Fluorescence 74. Conventional high temperature bleaching of cotton yarn is achieved with Vario Bleach in 15 minutes.
• Greige dyeing dye bath conditioner Sarbabid MLP – Multifunctional product (enzymatic, washing, emulsifying, dispersing, chelating properties and buffer) for controlled dyeing of cellulosic fibre with reactive dyes. Besides dark shades, it is possible to dye cotton/viscose and cotton blended with polyester.
• Dyeing and washing with cost effective Bezektive GO (anionic) at 40^oC. They are polyfunctional dyes having multifunctional groups with a shelf life of six months. Low consumption of water, energy and shortened process (exhaust and CPB). Direct cost of dyestuff and chemicals is 15% while indirect cost of water, energy, steam, machine hours and productivity is 85%.

–      Efficiency: Minimise ecological footprint with ease of washing off.

–      Cost effectiveness: Dyeing at 40^oC entails production cost reduced significantly and improvement in production capacity up to 50% in some cases.

• Intensity: Colours are highly intense resulting in lower requirements.
• Process safety: Exhaustion and fixation property, reproducibility of shade, homogeneous bath exhaustion in salt and alkali bath.
• Sustainability: 30% less water consumption, lower dyestuff and salt, 80% less energy and small amount of hydrolysed dye that can be easily washed off thereby effluent load is low besides saving 45% of time cycle.
• Cost saving: Dyeing cost eg for a lot of 250 kgs. Fixed cost, water and electricity are less when compared to conventional dyeing process and productivity increase almost by 40%, fixation rate of dyes (orange, red and navy) is 90% warranting less rinsing process.
• Summary: Dyeing and washing off at low temperature, reduction in dyes up to 40% and water consumption 30%, energy consumption 80%, lower amount of salt, reduction in environment type and low production cost.
• Innovative Soaping with Vario Soaping: Cotoblanc SEL helps in separation of dyebath hydrolysate and complex formation preventing redeposition on the fibre (optimum soaping efficiency in presence of high amount of salt in bath and alkaline pH). Reduction of rinsing bath and saving of water.

Summary: Soaping at 40-90^oC depending upon dye system used, efficiency independent of salt concentration in the dyebath. Time taken for light shades is 448 minutes while with Four Success Module, it is 367 minutes. Maximum saving of water up to 30% in case of dark shades; 70-75% energy and 30-35% time whereas light shades, saving of water up to 20%, energy 60% and time 20%.

Mr Nandan Prabhune, Thermax Limited (Energy and Environment) as a water and wastewater solution provider group, he spoke on wastewater treatment for the textile industries. He dealt with pollutants that enter water and interfere in recovering good quality of water conserving the environment. Alternatives available in technology to recover water at lower prices and to conserve resources. Recycle and reuse treated wastewater for various process applications.

• Wastewater characteristics: COD (1500-2500 mg/l); BOD to COD ratio 20-40%; TDS (2500-6000); colour from dyeing and printing. Colour removal by physicochemical treatment (chemicals mixed with water added to remove suspended solids or impurities in the form of sludge), biological or organic fraction degraded by microbes treated in bioprocesses (aerobic and anaerobic); recycle application by membrane technology (Ultra Filtration, Nano Filtration and Reverse Osmosis). Once secondary treatment is achieved, water will go for Zero Liquid Discharge. Footprint is smaller and significant colour removal is achieved.
• Treatment of water to secondary standards: PVA is one of the components that interferes in the treatment and anaerobic treatments are available for this stream. The disadvantage is higher biological sludge generation where dewatering could be difficult. Physicochemical treatment wherein chemical dose may not be same as the earlier ones followed by anaerobic as well as aerobic treatment resulting in 40% reduction in colour. Here the limitation would be the space required as compared to the previous option and with higher cost.
• Membrane technology solution: Newly developed treatment technology using membrane process has been adapted to get colourless water at various levels of concentration. The idea is to reduce colour wastewater which is going for treatment. They operated couple of pilot scale units at some locations effecting significant COD reduction from secondary treated water and could get 30-80 ppm.
• Permeate: Dissolved solids from water coming out of the membrane processes have lower TDS. Therefore water coming out could be used for secondary application like processing and dyeing. The major installation was at Arvind Mills with 500 cu m per hour, 5 streams of RO and in the plant secondary water is recycled for process application. The other is aerobic bioreactor to remove COD and BOD from wastewater.
• Summary: Treating wastewater with physicochemical followed by biological treatment would conserve resources. Solutions available could be applied to achieve Zero Liquid Discharge.

Panel discussion: When the well is dry, we know the worth of water (Benjamin Franklin). How many of us are using water responsibly? The panel discussed viable solutions to the current water crises for the benefit of textile industry.

Mr Anjani Prasad, Archroma India Private Ltd as moderator, gave a preamble to the water industry which is about 30-bn while textile, dyes and chemicals is about 10-bn going at the rate of 6% and developments taking place with respect to filtration technology using membrane and chemicals. Where do we have problems in saving water?

• Sizing entails starch with BOD and COD problems and some work may be done to reduce size content thereby saving water.
• Avoid cold and hot water leakage besides energy loss with the latter. Saving in preparatory processes; finishing, aqueous coating industry, hot melt (no water and no drying process). Chemicals which are used with BOD COD issues with bioelimination factor. About 40% is bioelimination while the need is 100%. Detergents used for washing and soaping are based on ethoxylates and the need is 80% biodegradation.
• Water is available in the ocean, wastewater, lakes, rivers and ground water. Besides industry, potable water is required for drinking. Water supplied to the mills and factories, after usage goes to ETP or CETP. Innovative processes are waterless dyeing, electrostatic dyeing besides 3D printing that dispenses with spinning, weaving and processing.

Mr Prakash Chavan, Executive Engineer said MIDC is the second largest water supplier in Maharashtra after the Bombay Municipal Corporation. In the technical presentations, Archroma and CHT have given solutions with their products for saving about 30% water, but at what cost? They should endeavour to produce chemicals that help to reduce water consumption and further treatments. Thermax produces wastewater treatment units and here again cost is an issue. MNCs like Clariant, Archroma etc may not have problems compared to SME units because MPCB has set up regulatory standards and based on turnover set up secondary treatment plant and discharge effluent to CETP. Their expectations are technology at affordable cost and to comply with norms. Water supply from lakes and tanks. Though water contamination exists, rain water harvesting through roof may be possible with due care. Chemical industries should produce technological products at a viable cost to effect saving of water.

Mr Amit Patjoshi, Associate Director, Infrastructure and Government Services, KPMG Advisory Services Private Ltd said that water is a limited resource and not a cheap resource. The solution has to come from both industry and the user. Proper standards across the supply chain regardless of the size of units and treat the water and pollution levels minimising costs and maximising outputs from industrial processes. Clusters of SME units working together standards and technology thereby distributing the cost in tandem. Address unaccounted water (32% UFW) on leakages by smart filter monitoring and no discharge of wastewater by recycle and reuse.

Mr Vinod Khetarpal CCol FSDC, Managing Director, Bombay Crimpers, said that the Government demanded ZDHC which is a difficult proposition and costly. Besides leakage 6% of water is wasted, which needs control and workers should be made more conscious of the importance of water. Yet, he is able to save up to 40% by metering the jet dyeing machines and brought down to 5% from 9% per batch. Cooling water is wasted and leakages are high. Yet water is cheap compared to chemical products eg 30 paisa for scouring and save water with the use of appropriate chemicals but cost would become more. Therefore chemical industry should emerge with products cheaper than water.

Mr Asish Chitre, Business Development Manager, DyStar said that dyes and chemicals and their optimisation would come with innovation in terms of new products. Improve processes to optimise consumption of water, dyes and chemicals which will end up in effluents. Challenge is cost and whether the cost of product would offset savings. This is difficult and you need to account for it. Trials have been carried out by dye and chemical manufacturers where the cost is optimised and cost offset of the product vs. overall cost of the process has been analysed. Besides, training at smaller units to make the staff and workers aware about the use of such technology, there have been efforts by the industry to bring down the cost of processing and inputs.

Compared to organised sector, SMEs find it hard to set up ETP due to high cost besides ROI concept and to form a cluster and to align is easier said than done. Focus is on trained and skilled labour required to control ETP operations. There is a need to train people.

A question/answer discussion followed. Chacha Industries, Satish Trading Co, Vishal Trading, Sharp Biotech Specialties Private Ltd, SMEW Textile Machinery Private Ltd and Thermax Ltd sponsored the event.

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