高级炭酸镁石棉砖,在解放前全部是依靠进口,解放后有些石棉厂已经能够制造,在制造这种高级石棉保温砖,各厂还都用炭酸镁做为填充剂,可是目前我国天然的炭酸镁矿还很少,所用的都是化学方法制造出来的,每吨售价在一千元以上,因此制出的炭酸镁石棉砖的售价也就很贵。我厂在1954年5月利用廉价的石膏代替炭酸镁试制硫酸钙石棉砖,获得初步成 Advanced magnesium carbonate asbestos bricks, all rely on imports before liberation, after the liberation of some asbestos plants have been able to manufacture, in the manufacture of such high-grade asbestos insulation bricks, the factory also use magnesium carbonate as a filler, but now our natural carbon acid Magnesium mines are still very few, and all of them are manufactured using chemical methods. They cost more than 1,000 yuan per ton, so the price of manufactured magnesium carbonate asbestos bricks is also very expensive. In May 1954, our factory made use of cheap gypsum to replace calcium carbonate for trial production of calcium sulfate asbestos bricks.