Critical Issues for Trouble-free Operation of Tube Digestion System

Hi Friends,

In earlier posts, we have already discussed about the design, engineering and operational aspects of Tube digestion system generally preferred for processing of Boehmitic Bauxite for production of alumina because of lower consumption of thermal energy. Total thermal energy consumption with Tube digestion works out to around 12 GJ per tonne of alumina which accounts for about 9 GJ/t for Bayer process (Hydrate) area and 3.0 GJ/t for calcination area.

In present post, we would like to have physical feel of Tube digestion system which may attribute in taking necessary precautionary measures while design, engineering and operational stages of the system. In this context, I would like to express my sincere thanks to one of our friends of Alumina fraternity who has shared with us two photographs clearly reflecting the pros and cons of the system being faced in one of the Alumina refineries in the World. In first photograph, the general arrangement of pipes are clearly visible where as in second photograph the nature of scaling can easily be experienced as shown below-

Both these photographs are the lessons for the designers and plant operators to take necessary precautionary measures in modifying the system while executing and operating new Alumina refinery in future.

It is needless to mention that Tube digestion system is most energy efficient methodology for processing Boehmitic Bauxite over other digestion technology available so far. However, the most amicable solution for maintaining the tubes free of hard scales need to be established for the operational ease. These photographs supplements our statements and apprehensions presented in previous posts on the subject.


Request to put your views / suggestions / remarks / comments, if any.
Regards.


Kunwar Rajendra