天然白云石合成镁钙砂新工艺的研究

结合一步煅烧与两步煅烧工艺,采用粒度8～5、5～3、3～1 mm的天然白云石,研究了900、950、1 000、1 100℃轻烧温度下原料的活性和烧结性能;通过改变生料与消化料的混合比例,研究了镁钙砂的烧结性和抗水化性。结果表明:最佳的轻烧条件是粒径8～5 mm,轻烧温度1 000℃;随着生白云石粉含量的增大,镁钙砂的体积密度先增大后减小,在生白云石粉质量分数为50%时镁钙砂的烧结性能最好,体积密度最大可达到3.35 g.cm-3;生白云石粉的质量分数<50%时对合成镁钙砂的抗水化性能影响不大,当生白云石粉的质量分数>50%时,其抗水化性能急剧下降。

Synthesis of magnesia-calcia clinker from raw dolomite

Combined one-step calcination process with two-step calcination process,the activity and sintering property of raw dolomite(particle size of 8-5,5-3,3-1 mm) light-calcined at 900,950,1 000,and 1 100 ℃,respectively,were studied.Sintering property and hydration resistance of magnesia-calcia clinker were studied by changing the proportion of raw dolomite and slaking product.The results show that the optimal light-calcining condition is particle size of 8-5 mm and calcining temperature of 1 000 ℃;as the raw dolomite powder content increasing,bulk density of magnesia-calcia clinker increases first and then decreases;when raw dolomite addition is 50 mass%,magnesia-calcia clinker has the best sintering property and its bulk density can reach 3.35 g·cm-3;when raw dolomite powder content is <50 mass%,the influence of dolomite on the hydration resistance of magnesia-calcia clinker is not obvious,when raw dolomite powder content is >50 mass%,the hydration resistance declines rapidly.