To produce metallic aluminum (electrolytic aluminum), the first step is to produce alumina. Almost all the alumina in the world is produced by alkali method, which is divided into Bayer method, sintering method and Bayer-sintering combined method, with Bayer method as the main method. It takes two tons of alumina to produce one ton of metal aluminum. According to information, in 2002, my country’s electrolytic aluminum production required 8.52 million tons of alumina, domestic supply of 5.48 million tons, and imports of 3.04 million tons. In 2003, 11 million tons of alumina was needed, 6.15 million tons were supplied domestically, and 4.85 million tons were imported. Solving the domestic alumina gap is a big problem.