Electric and Hybrid Cars – FAME, National Electric Mobility Mission, etc.

Ethanol production in India

Note4Students

From UPSC perspective, the following things are important :

Prelims level : Ethanol, EBP programme

Mains level : Ethanol production in India

  • The MoEFCC announced that mills would not require separate environmental clearance to produce additional ethanol from B-heavy molasses.
  • The ministry clarified that the proposals to undertake additional ethanol production from B-heavy molasses/sugarcane juice/sugar syrup/sugar would be considered under the provisions of the EIA Act, 2006.

What are ethanol and molasses?

  • Ethanol, or ethyl alcohol, is a liquid that has several uses.
  • At 95% purity, it is called rectified spirit and is used as the intoxicating ingredient in alcoholic beverages. At 99%-plus purity, ethanol is used for blending with petrol.
  • Both products are made from molasses, a byproduct of sugar manufacturing.
  • For making sugar, mills crush sugarcane which typically has a total fermentable sugars (TFS) content of 14%.
  • The TFS component consists of sucrose along with the reducing sugars glucose and fructose.
  • Most of this TFS component gets crystallized into sugar, and the remaining part is called molasses.

Molasses stages

  • The molasses go through three stages — A, B, and C, the last one being where the molasses are most un-crystallised and non-recoverable.
  • The ‘C’ molasses roughly constitute 4.5% of the cane, and have a remaining TFS of 40%.
  • After C-molasses are sent to the distillery, ethanol is extracted from them. Every 100 kg of TFS yields 60 litres of ethanol.
  • Thus, from one tonne of cane, mills can produce 115 kg of sugar (at 11.5% recovery) and 45 kg of molasses (18 kg TFS) that gives 10.8 litres of ethanol.

How more ethanol can be produced?

  • Mills can also produce only ethanol from sugarcane, without producing sugar at all.
  • In this case, the entire 14% TFS in the cane is fermented. Here, a mill can make 84 litres of ethanol and zero kg of sugar.
  • In between the two extreme cases, there are intermediate options as well, where the cane juice does not have to be crystallised right till the final ‘C’ molasses stage.
  • The molasses can, instead, be diverted after the earlier ‘A’ and ‘B’ stages of sugar crystal formation.
  • Mills, then, would produce some sugar, as opposed to fermenting the whole sugarcane juice into ethanol.

What new clearance aims?

  • If ethanol is manufactured using ‘B’ heavy molasses (7.25% of cane and with TFS of 50%), around 21.75 litres will get produced along with 95 kg of sugar from every 1 tonne of cane.
  • The latest move by the government is to waive the environmental clearance required to produce ethanol at this stage.
  • In the press release, it has been explained that this was done since this process does not contribute to the pollution load.

Why focus on more ethanol?

  • Mills currently have all-time-high stocks of sugar, and they have been at loggerheads with farmers over non-payment of dues.
  • Mill owners insist that the reason behind their woes is excess production of sugar and fall in its price.
  • Under the circumstances, ethanol is the only real saviour — both for mills and cane growers.
  • Ethanol production has been additionally facilitated with the government mandating 10% blending of petrol with ethanol.
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