The invention discloses a technology method used for producing poly 
aluminium chloride and 
calcium aluminate. The technology method comprises following steps: 1, ash stir frying is carried out, and 
metal aluminum is recycled so as to obtain secondary aluminum ash; 2, the secondary aluminum ash is subjected to 
deamination processing so as to obtain a deaminated aluminum ash 
slurry; 3, the deaminated aluminum ash 
slurry is subjected to defluorination 
processing so as to obtain a defluorinated aluminum ash 
slurry; 4, the defluorinated aluminum ash slurry is filtered so as to obtain a filtrate anda 
filtration residue, wherein the filtrate is a poly 
aluminium chloride solution; and 5, the 
filtration residue is washed until the pH value is 7, is uniformly mixed with a 
calcium based auxiliary material, 
drying and high temperature reaction are carried out, after reaction, cooling, crushing, and 
grinding processing are carried out so as to obtain 
calcium aluminate. According to the technologymethod used for producing poly 
aluminium chloride and calcium 
aluminate, secondary aluminum ash is subjected to complete harmless processing, so that high efficiency 
resource utilization of secondaryaluminum ash is realized, and the produced products possess better economical benefit.