Abstract: Compression strength variation rule and improve method were studied by using preheated pellets with and without cooling as the burden.The result shows that in the case of equal added binder, the compressive strength of reduced pellets via thermal charging improves obviously; With addition of the binder the compression strength of reduced pellets increases.The reduction speed of thermal charging is slower than the cold-one.Added 1.5% F binder and reduced for 30min,the reduction degree of cold charging and hot charging respectively reached 95% and 90%.

Key words: Preheated pellets, Gas-based reduction, Compression strength, Direct reduced iron