Alumina
(Al2O3) is very important material plays essential role
in Aluminum manufacturing fields. More than 90% of alumina produced worldwide
is consumed in the production of Aluminum. Nowadays, Aluminum is found
everywhere.
The
objective of this project is to design and analyze an Alumina production plant
by using Bauxite ore as a raw material which will be imported from Guinea and
manufactured in the United Arab Emirates. The capacity of this plant is 5 Mton/y.
The selected process was Bayer process. This selection has been done based on
economic issue, environmental friendly and efficiency degree. To give a quick
overall view of the process; a grinded Bauxite with streams of hot water and
NaOH (NaOH solution) are mixed and reacted in the reactor called a digester.
Then, the result of sodium aluminate solution will be separated from insoluble
red mud that is the main waste in the process with high pH. After that, by
cooling the stream, Aluminum Hydroxide will precipitate from the solution and
crystals of aluminum trihydroxide (Al(OH)3) will be formed, then the
crystals will be calcined to produce the alumina. Data gathering and literature
surveys have been done to determine the most suitable plant design and operation
conditions. Also, the material and energy balances have been performed on the
selected process. Then, the design of the main units (the digester, the
clarifier, the heat exchanger, the precipitator, the rotary kiln and the pump)
was done. Then, the economical study was done to get a feasibility study of the
project. Finally, the HAZOP study was done for the units that have high
probable risk. There were some difficulties face in the project like designing
units that handle solid materials, and some missing data.