The Central Pollution Control Board (CPCB) is formulating plans address pollution from distilleries, one of the major sources of pollution in the country. There are 319 distilleries in the country, of which 285 are operational. They produce 3.25 billion litres of alcohol per annum. However, along with alcohol, they also produce almost 40.4 million litres of waste water or spentwash annually.
“Almost 10 kilolitre of waste water is generated in producing one kilolitre of alcohol. We are developing techniques like multi-effect evaporator (MEE) because of which only two kilolitres water will be wasted in the entire process of alcohol production. The other technique is to utilise spentwash as an auxiliary fuel in a cement kiln. This plan is in line with the government's zero-liquid discharge norms for distilleries,” said A B Akolkar, additional director, CPCB.
Only 40 per cent of the waste water generated in the distilleries is reusable after alcohol production. But it cannot be used for drinking purposes. Moreover, because of shortage of molasses, many of them have shifted to grain-based alcohol production. The ultimate aim for these molasses-based distilleries is to have zero discharge of water by completely utilising it in the system. The carbon in the residue should be used to generate energy.
Radico Khaitan, the number two company in the Indian Made Foreign Liquor market, too is planning to go for MEE despite the technology costing Rs 40-45 crore initially, with an operating cost of Rs 3 per litre of alcohol. “We have not used MEE as yet but we are looking at alternative technologies as there is zero liquid discharge with it,” said Devendra Singh, vice president, production at Radico Khaitan.
In fact, the government aimed to achieve 100 per cent utilisation of spentwash by December 2005 to ensure zero discharge in inland surface water courses, with 50 per cent utilisation to be realised by March 2004.
The Ministry of Environment and Forests had said that the nutrient value of effluents would be utilised by making compost. The ministry had also said till 100 per cent utilisation of spentwash was achieved, discharge of treated effluent would be regulated to prevent colouring of water bodies.
India produced 1,800 million litres of alcohol last year and this year’s estimate stands at 2,200 million litres. “The actual production is always 60-65 per cent of the actual capacity of 4,000 million litres annually,” said V N Raina, director general of the All-India Distillers’ Association.
Akolkar said that distilleries should utilise the spentwash in a cement kiln because it is rich in carbon and can be used as an auxiliary fuel. “Another way to reduce the amount of spentwash is by converting the residual sugar into alcohol. It should also be noted that grain-based distilleries have less pollution load as compared with molasses-based ones,” he explained.
“Of the total distilleries in the country, only 10 are purely grain-based and these are less polluting than molasses-based distilleries. Also, spentwash of molasses is difficult to treat and very expensive,” Raina added.
However, Raina explained that treating the spentwash from a distillery of 60,000 kilolitres of capacity costs around Rs 5-6 crore. Hence, distilleries have started using different techniques to reuse this spentwash, like biocomposting, reverse osmosis and incineration. “But incineration is a high power consuming process and hence, most distilleries are biocomposting the spentwash because other processes are expensive,” he said.
While industries like aluminium, cement and thermal power plants have adopted improved environmental practices, industries like distilleries, pesticides, dye intermediate and pharmaceuticals are coming forward slowly to give the desired response.
“Most companies are using technologies that lead to zero liquid discharge. We do biocomposting and there is only an uploading cost of investing in technology. The costs do not go up substantially,” said the CEO of the India arm of a leading global beverages company. He added that the cost of the evaporator was 20 per cent of the distillery cost while it cost another 8-10 per cent of the total production cost to run this system.
