Method of producing iron ore pellets

Abstract

Provided is a method of producing iron ore pellets that produces green pellets that have high strength and can suppress bursting. The method of producing iron ore pellets includes: a process of mixing iron ore having a total Fe content of 63 mass % or less and a binder to obtain a mixture; a process of granulating the mixture to obtain green pellets; and a process of firing the green pellets to obtain iron ore pellets. The iron ore includes core ore 10 having a particle size of more than 1 mm and fine ore 12 having a particle size of 1 mm or less.

1 . A method of producing iron ore pellets, the method comprising:
 a process of mixing iron ore having a total Fe content of 63 mass % or less and a binder to obtain a mixture;   a process of granulating the mixture to obtain green pellets; and   a process of firing the green pellets to obtain iron ore pellets,   wherein,   the iron ore comprises core ore having a particle size of more than 1 mm and fine ore having a particle size of 1 mm or less.   
     
     
         2 . The method of producing iron ore pellets according to  claim 1 , wherein the mass fraction of the core ore is 15 mass % or more of the iron ore. 
     
     
         3 . The method of producing iron ore pellets according to  claim 2 , wherein the mass fraction of particles having a particle size of more than 2.8 mm in the core ore is 15 mass % or more of the iron ore. 
     
     
         4 . The method of producing iron ore pellets according to  claim 2 , wherein the mass fraction of particles having a particle size of more than 2.8 mm in the core ore is 30 mass % or more of the iron ore. 
     
     
         5 . The method of producing iron ore pellets according to  claim 1 , wherein the mass fraction of particles having a particle size of more than 4.8 mm in the core ore is 10 mass % or more of the iron ore. 
     
     
         6 . The method of producing iron ore pellets according to  claim 5 , wherein the mass fraction of particles having a particle size of more than 4.8 mm in the core ore is 25 mass % or more of the iron ore. 
     
     
         7 . The method of producing iron ore pellets according to  claim 1 , wherein the particle size and mass fraction of the core ore are set so that the number of particles of the core ore contained per iron ore pellet is on average 0.9 to 1.0. 
     
     
         8 . The method of producing iron ore pellets according to  claim 1 , wherein the iron ore material is sieved through a sieve having a 1 mm mesh size, the iron ore material that does not pass through the sieve is used as the core ore, and the iron ore material that passes through the sieve is ground and used as the fine ore. 
     
     
         9 . The method of producing iron ore pellets according to  claim 1 , wherein, in the mixture, when W1 is the mass of the fine ore and W2 is the mass of the binder, W2/W1×100 is 1.0 or more. 
     
     
         10 . The method of producing iron ore pellets according to  claim 1 , wherein the binder is bentonite.