mgo board production line used mgcl2 mgnesium choloride Mgcl2>93, K<0.01,Na<0.01, Ga<0.005, Fe<0.02, Si<0.005 mgo board production line used mgcl2 mgnesium choloride.Mgcl2>93, K<0.01,Na<0.01, Ga<0.005, Fe<0.02, Si<0.005 Used for MGO building materials production line.