The invention relates to a method for operating a fluidized bed boiler (6), comprising the steps of: a) providing fresh ilmenite particles having a shape factor of 0.8 or lower as bed material to the fluidized bed boiler (6); b) carrying out a fluidized bed combustion process; c) removing at least one ash stream comprising ilmenite particles from the fluidized bed boiler; d) separating ilmenite particles from the at least one ash stream, wherein the separation includes a step of using a magnetic separator (12) comprising a field strength of 2,000 Gauss or more; e) recirculating separated ilmenite particles into the bed of the fluidized bed boiler; wherein the average residence time of ilmenite particles in the fluidized bed is 100 h or more.

The invention relates to a method for operating a fluidized bed boiler (6), comprising the steps of: a) providing fresh ilmenite particles having a shape factor of 0.8 or lower as bed material to the fluidized bed boiler (6); b) carrying out a fluidized bed combustion process; c) removing at least one ash stream comprising ilmenite particles from the fluidized bed boiler; d) separating ilmenite particles from the at least one ash stream, wherein the separation includes a step of using a magnetic separator (12) comprising a field strength of 2,000 Gauss or more; e) recirculating separated ilmenite particles into the bed of the fluidized bed boiler; wherein the average residence time of ilmenite particles in the fluidized bed is 100 h or more.

The present invention relates to a CLC and operation method thereof equipped with a loop seal separator using magnetic oxygen carrier particles and a magnetic separator. And more particularly, the present invention relates to a loop seal separator using magnetic oxygen carrier particles and a magnetic separator, wherein the loop seal separator comprises a duct into which the ash and magnetic oxygen carrier particles, discharged from a reducer, flow; a magnetic separator to separate the ash from the magnetic oxygen carrier particles, flowing into the duct, by magnetic material; an ash discharge pipe to discharge the ash, separated by the magnetic separator; and an oxygen-carrier-particle discharge pipe to encourage the magnetic oxygen carrier particles, separated by the magnetic separator, to flow into an oxidizer.

The present invention relates to a CLC and operation method thereof equipped with a loop seal separator using magnetic oxygen carrier particles and a magnetic separator. And more particularly, the present invention relates to a loop seal separator using magnetic oxygen carrier particles and a magnetic separator, wherein the loop seal separator comprises a duct into which the ash and magnetic oxygen carrier particles, discharged from a reducer, flow; a magnetic separator to separate the ash from the magnetic oxygen carrier particles, flowing into the duct, by magnetic material; an ash discharge pipe to discharge the ash, separated by the magnetic separator; and an oxygen-carrier-particle discharge pipe to encourage the magnetic oxygen carrier particles, separated by the magnetic separator, to flow into an oxidizer.