Sintered Alumina
Process
A process for the production of sintered alumina grains from indigenously available cal-cined alumina.
Uses
Finds major application in the manufacture of special refractories such as slidegate plates, low cement castables, high alumina bricks etc.
Salient Features
The raw material such as, calcined alumina and suitable additives are intimately mixed in proper proportions and pellets are formed at optimum pressure. These pellets are sintered at about 1700°C for 2/3 hours in air /oxidising atmosphere. The sintered pellets are then crushed, ground and sieved to desired fractions followed by magnetic separation. The grains contain minimum 99.0% alumina and have 5-6% A.P.
Environmental Considerations
The process does not present any effluent problem and is almost free from pollution.
Scale of Development
The process has been developed on laboratory scale.
Commercialisation Status
Licensed to M/s Tata Refractories Ltd., Belpahar (Orissa), 360 tpa and is in commercial production.
Major Raw Materials
- Calcined alumina (minimum 99.5% Al2O3)
- Additives
Major Plant Equipment/Machinery
Mixer, Briquetting press, High temperature furnace, Jaw crusher, Roll crusher, Ball Mill, Magnetic Separator. All indigenously available.
Techno-Economics
A plant with 600 tpa capacity (based on 3 shifts per day and 300 working days per annum) costs Rs. 125.00 lakhs. ROI is 45% at a selling price of Rs. 45,000/- per tonne.
Technology Package
Includes
- Process know-how
- Details of equipment
- Plant lay-out
- Quality assurance methods. Assistance in setting up the plant on separate terms.
Released Through
NML/CSIR
For further information please contact
Director
National Metallurgical Laboratory
Jamshedpur-831 007, India
