Industrial Production of Ethanol from Sugar Cane (1 Viewer)

[ruchikavera]

I know there have been many posts on this but they were all a bit confusing :S So, I'm hoping to clear this up

Here's what I've gathered from various sources about the steps, please correct me if I'm wrong:

• Grains from sugar cane are passed through hammer mills and ground to a fine powder.
• This meal is sent to a mashing system, where it is mashed together with enzymes and water.
• This then undergoes hydrolysis (decomposition by water), catalysed by the enzyme, invertase:
  C12H22O11_(aq) + H2O_(l) --> C6H12O6_(aq) + C6H12O6_(aq)
  (sucrose) + (water) --> (glucose) + (fructose)
• The sugars are filtered: the solid residue is continually hydrolysed with more acid until it too has broken down into sugars.
• Ca(OH)2 is added to the acidic sugar solution (filtrate) to neutralise it.
• The neutralised sugar solution is filtered to remove the solid residue of CaSO4.
• Ferment the sugar solution, using enzymes produced by the yeast called zymase, to produce ethanol:
  C6H12O6_(aq) ---> 2C2H5OH_(aq) + 2CO2_(g)
  - Yeast used is Saccharomyces cerevisiae
  - Small amounts of yeast nutrients are added, such as phosphoric acid or urea
  - Mixture is kept at 37 degrees Celsius.
  - Oxygen is excluded
• Fermented product (6-10% ethanol) is sent to the purification section.
• Distillation of the ethanol/water produces a higher concentration of ethanol (96%).
• This is then dehydrated to remove the last water molecules and impurities. After this, the ethanol can be sold commercially.

So, is this all I need in order to address the dot point thoroughly?

 

[madharris]

It look right except that the BOS wants the temp to be 25-35ºC not 37ºC

well that's what my teacher and past papesr have told me

 

[delian]

No, I think 37 degrees should be right- human body temp. But I don't think BOS would be too picky.