Study On The Mechanism And Technology Of Lime-sintering Alumina Production Process Based On Monocalcium Aluminate

The main phases of calcium aluminate clinker are 12CaO·7Al₂O₃(C₁₂A₇)and?-2CaO·SiO₂??-C₂S?,But the C/A ratio?mol ratio?of C₁₂A₇ is high,and this leads to high consumption,high energy consumption,high quantity of slag,high cost of the production process,and energy consumption.To solve these problems,CaO·Al₂O₃?CA?was used to replace C₁₂A₇ to reduce the cost.The synthesis problem and the leaching property of CA;the leaching property of the mechanical mixture of CA and?-C₂S;the influence of low C/A ratio and low A/S ratio on calcium aluminate clinker;the influence of temperature on calcium aluminate clinker;and the leaching property of calcium aluminate clinker were studied in this paper.The equilibrium mechanism influence of calcium aluminate clinker phase is studied by SEM,X-ray diffraction?XRD?,X-ray fluorescence analysis.The results show that:?1?when C/A is 1.0,CA can be obtained by sintering under1500?for 120 min,the alumina leaching ratio of clinker can be up to 99.83%.?2?CA and the mechanical mixture of CA and?-C₂S have no difference on leaching ratio of alumina,both of them can be up to 99.51%,the secondary reaction which decrease the alumina leaching ratio doesnot appear under this condition.?3?The clinker consisting mainly of CA and?-C₂S was successfully synthesized when C/A is 3,and its optional alumina leaching ratio is 95.36%.?4?The self-disintergtating ratio and the leaching ratio do not change significantly with the increase of C/A?1.0¹.2?when A/S is 3.0;the changes of A/S?1.0⁴.0?has little effect on phase composition when C/A is 1.0,the self-disintering ratio decreases and alumina leaching ratio increases with the increase of A/S under the conditions mentioned above.?5?The alumina leaching ratio and the self-disintergtating ratio of clinker are higher when the speed of rising temperature is faster.the influence of cooling rate on phase composition,self-disintergtating properties and leaching properties of the slag are not obvious,the clinker of high alumina leaching rate and excellent self-disintergtating property was synthesized under 1350?for30⁶0min.