Reference no: EM132301928 , Length: word count:2000

Bioprocess Engineering Assignment - Bioprocess (Fermenter) design and safety

Ethanol is to be produced through batch fermentation of corn using a strain of Saccharomyces Cerevisiae under anaerobic conditions and using wet milling process. The plant is to be designed to produce 1.5 million tonnes of ethanol.

1. With the aid of a process flow diagram, give a brief description of the wet milling process to produce ethanol from corn using anaerobic fermentation. Include operating conditions for each of the major steps in the process.

2. Design the fermentation unit to deliver 1.5 million tonnes of ethanol per annum operating in batch mode. You can assume that glucose is the limiting nutrient and after the saccharification step, the broth entering the fermenter contains 180 g/l of glucose. Your design should include the following:

a. Size and number of fermenters required to achieve the target throughput including fermenter dimensions which should take into account vapour headspace.

b. Number of operating days per year.

c. Type of mixer (impeller) and its power requirements to ensure that mass transfer requirements are met.

d. Heat transfer requirements and how they will be achieved.

e. Material used for construction of the fermenter and the wall thickness.

The design report should clearly state the assumptions made and justification for any choices that are made in the design calculations. It should also make appropriate references to literature and wherever possible try to optimise the fermenter operation including reduction of energy requirements.

3. Carry out a risk assessment on fermenter operation and indicate the mitigating steps to be taken so that the risk is reduced to as low are reasonably possible (ALARP). Use the risk matrix and risk assessment form discussed in class for this purpose.