As discussed in previous articles, about 89% of alumina produced in the World is used for manufacture of aluminium metal and remaining 11% for production of chemicals and other non-metallurgical applications. Thus calcined alumina as well as hydrated alumina (Hydrate) is broadly characterized in two categories-
- Metallurgical grade alumina or Smelter grade alumina (MGA or SGA)) and
- Non-metallurgical grade alumina or Chemical grade alumina (NMGA or CGA).
As per data available on public domain, bauxite is available in Tayan, Munggu Pasir, Mempawah and West Kalimantan region in Indonesia. West Kalimantan is having total bauxite reserves of over 2000 million tonnes with proven reserves of over 800 million tonnes of bauxite. The bauxite is predominantly gibbsitic in nature with average quality of about 43% total alumina, about 38.6% available alumina and around 3% reactive silica. The bauxite in Indonesia has been seen in low lying hills with overburden varying from 0.60 m to 3.8 m and nodular bauxite horizon from 2.2 to 5.2 m. The geographical studies indicate that these bauxite deposits were formed by in-situ weathering. Till last year, the country was exporting bauxite to china and other countries but in the recent past, the Indonesian government has totally banned the export of bauxite and putting more focus on processing of bauxite for production of value added products.
In Indonesia, there are two major Alumina projects in West Kalimantan namely Tayan Alumina Project and Mempawah Alumina Project under execution and active consideration as outlined here under.
Tayan CGA Project: Tayan bauxite mine commenced its operation in early 2010 and was exporting bauxite to China and Japan. Construction of Tayan Alumina Project was started in April 2011 aiming to mechanical completion schedule in December 2013 and trial production in January 2014. The capacity of this plant is 0.300 million tonnes for production of wide varieties of Chemical grade hydrates and aluminas. The estimated project cost is US$ 490 million with the technology supplied by Showadenko (SDK), Japan. The actual mechanical completion of this project is expected by end of December 2014 and commercial production by March 2015.
Mempawah SGA Project: The capacity of this plant is 1.2 million tonnes of SGA to be supplied as feed stock to Aluminium Smelter. The estimated capital investment will be about US$ 1.5 billion. The construction of this plant will be started by early 2015 with mechanical completion target of December 2017.
We seek your valued comments / opinions / additional information, if any.