Part 2 2&j Fermentation and distillation 1. Maize can be consumed directly by humans and animals, but it is also used to produce ethanol as a fuel substitute or processed into corn syrups. Conversion of maize kernels into ethanol involves the following production steps: milling and soaking, boiling, cooling and enzyme hydrolysis, fermentation with yeast, centrifugation and finally distillation before molecular filtration. Milled maize kernels have the following composition. a. One maize-to-ethanol plant processes 5000 tons of milled maize per day by adding 2.50 L of water per kg of milled maize. Identify the mass flow rates (kg/s) in and out of the enzyme digestion process and show these on the diagram below b. The mixture of carbohydrates, lipids and water is added to a batch fermenter (4000L) with yeast (Saccharomyces cerevisiae) at 35.0C. The yeast grows rapidly and anaerobically respires at a rate of 2000 moles of glucose (C6H12O6) per second in this reactor. The anaerobic respiration of hydrolysed carbohydrates by yeast can be shown by: C6H12O62C2H5OH+2CO2H=34.5kJ/mol of ethanol Determine the flow rate (kg/s) of cooling water required to maintain the fermenter at 35.0C. You may assume there are no other heat losses, and the specific heat capacity of the cooling water is 4.18J/g.K with an input temperature of 5.0C and an output temp 30.0C. c. During this fermentation one batch becomes contaminated with bacteria which can be killed by lowering the pH from 6.00 to 1.95. The additional acid does not react with carbohydrates or lipids or yeast. Calculate the volume of 2.50M sulphuric acid which is required to achieve the pH of 1.95 of this batch? Assume the sulphuric acid dissociates completely and this additional acid does not change the total volume significantly