Ethanol from Cassava

Ethanol is generally produced by the fermentation of sugar, cellulose, or converted starch and has a long history. In Nigeria, local production of ethanol from maize, guinea corn, millet, other starchy substrates, and cellulose is as old as the country itself. Apart from food and pharmaceutical uses, ethanol is finding itself alternative usse for biofuel in most of the developed world for the following reasons:
Cassava Ethanol ProcessFlowchart
It is not poisonous.
It does not cause air pollution or any environmental hazard.
It does not contribute to the greenhouse effect problem (CO2 addition to the atmosphere, causing global warming).
It has a higher octane rating than petrol as a fuel. That is, ethanol is an octane booster and anti-knocking agent.
It is an excellent raw material for synthetic chemicals.
Ethanol provides jobs and economic development in rural areas.
Ethanol reduces country’s dependence on petroleum and it is a source of non-oil revenue for any producing country.
Ethanol is capable of reducing the adverse foreign trade balance.
Equipment required
Peeler
Grater
Jet cooker
Fermentor
Distiller
Steam boiler
Generator
Efficient treatment plant
Basic plant
The first type of plant will produce a strong alcohol from cassava, but this will have an odor as the distilling process is very crude. The plant would bring in fresh cassava, wash and peel, grate, cook in a jet cooker, ferment, distil, and bottle. In addition a steam boiler, generating set, effluent treatment plant and electrical system are required. The actual amount of cassava needed is dependant upon the starch content, but as a guide, cassava at 30% starch content will produce approximately 280 liters of alcohol/tonne. Cassava which is only 20% starch will produce only 180 liters of alcohol/tonne.
The plant will produce approximately 3000 liters/day of alcohol at 96%, which equivalent to 7500 liters/day at 40%. The plant will also produce around 2-3m3/hr of effluent. This has to be disposed of properly and is normally used as an animal feed. This plant operates on a batch basis and can process approximately 4-6 batches/24 hours, producing 500 liters of alcohol/batch. The plant will need good water supply and continuous electrical supply (around 50Kva). The steam requirements are around 1500 kg/hour.
The cost will be in the region of £290,000 which includes all the equipment, shipping, supervision of installation, commissioning, and operator training.
Complex plant
The next type of plant will produce a better quality of alcohol from cassava, and uses a multi-column still so that the complex distilling techniques employed ensures a high quality product, free from all types of odors, etc. The plant would bring in fresh cassava, wash and peel, grate, cook in a jet cooker, ferment, distil, and bottle. In addition a steam boiler, generating set, effluent treatment plant, and electrical system are required. The actual amount of cassava needed is dependant upon the starch content, but as a guide cassava at 30% starch content will produce approximately 280 liters of alcohol/tonne. Cassava which is only 20% starch will produce only 180 liters of alcohol/tonne.
The plant will produce approximately 4000 liters/day of alcohol at 96%, which is equivalent to 10,000 liters/day at 40%. The plant will also produce around 2-3m3/hr of effluent. This has to be disposed of properly and is normally used as an animal feed. This plant operates on a batch basis and can process approximately 4-6 batches/24 hours, producing 500 liters of alcohol/batch. The plant will need a good water supply and a continuous electrical supply (around 50Kva). The steam requirements are around 1500 kg/hour.
The cost will be in the region of £620,000 which includes all the equipment, shipping, supervision of installation, commissioning, and operator training.