The invention discloses a method for producing sandy aluminum
oxide by treating aluminum ash through a
soda lime sintering method, and belongs to the technical field of
aluminum industry environmental protection. According to the invention, the aluminum ash,
sodium carbonate and limestone are mixed according to a certain proportion, high-temperature
sintering is directly carried out, and the sandy
alumina is obtained through the procedures of ball milling alkaline leaching,
solid-liquid separation, deep desilicication, carbon component strengthening and the like, so that the risk that toxic combustible and explosive gases such as
ammonia gas,
methane,
hydrogen and the like are generated when the traditional aluminum ash is washed with water is avoided; salt such as
chlorine salt and villiaumite volatilized at high temperature is prepared into the aluminum
smelting fluxing medium according to a proper proportion, so that high-value
resource utilization of the aluminum ash is realized. The efficient desiliconizing agent is prepared from
barium aluminate, hydrated
calcium aluminate, hydrated
calcium carboaluminate and
lime milk according to a certain proportion, the desiliconizing effect is greatly improved compared with that of traditional
lime milk, and a
solid guarantee is provided for producing qualified sandy
alumina. The concentration of
carbon dioxide adopted for common carbon separation is 30-40%, the concentration of
carbon dioxide in
tail gas generated by the
rotary kiln is about 10%, and the carbon separation efficiency is low, so that the concentration of
carbon dioxide generated by the
tail gas of the
rotary kiln can be increased to 60-70% by adopting a purification-special
silica gel pressure swing adsorption mode; the
decomposition rate of the
sodium aluminate solution and the yield of aluminum
hydroxide are greatly improved, the effect of enhancing carbon content is achieved, carbon dioxide generated by the
tail gas of the
rotary kiln is reasonably utilized, and the carbon emission is reduced.