Boiler for iron fuel combustion arrangement

Abstract

The present invention relates to an iron fuel boiler process for iron fuel combustion, comprising the steps of combusting an iron fuel suspension medium comprising iron fuel and oxygen in an iron fuel burner arrangement to obtain an iron oxide containing medium; receiving the iron oxide containing medium into an iron fuel boiler arrangement for transferring the iron oxide containing medium towards a separation unit disposed at the end of said iron fuel boiler arrangement; exchanging heat between the iron oxide containing medium and a boiler of the iron fuel boiler arrangement with a heat-exchange medium during the transfer of the iron oxide containing medium through said iron fuel boiler arrangement; and separating iron oxide from the oxide containing medium to obtain solid iron oxide particles and a gas flow. The process further comprising the step of cooling said iron oxide containing medium with a cooling medium during said transfer of the iron oxide containing medium through the iron fuel boiler arrangement such that a temperature of the iron oxide is achieved of below the sintering temperature of the particles at said separation unit.

1 . An iron fuel boiler process for iron fuel combustion, comprising the steps of:
 combusting an iron fuel suspension medium comprising iron fuel and oxygen in an iron fuel burner arrangement to obtain an iron oxide containing medium;   receiving said iron oxide containing medium into an iron fuel boiler arrangement for transferring said iron oxide containing medium towards a separation unit disposed at an end of said iron fuel boiler arrangement;   exchanging heat between said iron oxide containing medium and a boiler of said iron fuel boiler arrangement with a heat-exchange medium during said transfer of said iron oxide containing medium through said iron fuel boiler arrangement;   separating iron oxide from said iron oxide containing medium to obtain solid iron oxide particles and a gas flow;   
       said process further comprising the step of:
 cooling said iron oxide containing medium by mixing the iron oxide containing medium with a cooling medium during said transfer of said iron oxide containing medium through said iron fuel boiler arrangement such that a temperature of said iron oxide is achieved of below the sintering temperature of said solid iron oxide particles at said separation unit. 
 
     
     
         2 . The iron fuel boiler process according to  claim 1 , wherein a temperature of said iron oxide is achieved of below 800° C. at said separation unit. 
     
     
         3 . The iron fuel boiler process according to  claim 1 , wherein said iron fuel boiler arrangement comprises air inlet means arranged for said cooling step. 
     
     
         4 . The iron fuel boiler process according to  claim 1 , wherein said iron fuel boiler arrangement comprises water inlet means arranged for said cooling step. 
     
     
         5 . The iron fuel boiler process according to  claim 1 , wherein said step of cooling is performed during said exchange of heat. 
     
     
         6 . The iron fuel boiler process according to  claim 5 , wherein said step of cooling is performed during part of said exchange of heat. 
     
     
         7 . The iron fuel boiler process according to  claim 1 , further comprising the step of:
 exchanging heat between said gas flow and said boiler of an iron fuel boiler arrangement, with a heat-exchange medium after said separation of said iron oxide from said oxide containing medium.   
     
     
         8 . The iron fuel boiler process according to  claim 1 , wherein said step of cooling comprises:
 cooling down said iron oxide containing medium while said oxide containing medium is directed away from a wall surface of said iron fuel boiler arrangement.   
     
     
         9 . The iron fuel boiler process according to  claim 8 , wherein said iron fuel boiler arrangement comprises a boiler housing geometry arranged for said cooling to direct said oxide containing medium away from said wall surface by said geometry. 
     
     
         10 . The iron fuel boiler process according to  claim 8 , wherein said iron fuel boiler arrangement comprises air inlet means arranged for said cooling step to direct said oxide containing medium away from said wall surface. 
     
     
         11 . The iron fuel boiler process according to  claim 1 , wherein said transfer of said iron oxide containing medium towards said separation unit takes place in a vertically downwards direction. 
     
     
         12 . The iron fuel boiler process according to  claim 1 , wherein separating iron oxide from said oxide containing medium is performed to such a degree that at least 95 wt. % iron oxide particles with a size of at least 10 μm, are separated from said oxide containing medium. 
     
     
         13 . The iron fuel boiler process according to  claim 1 , wherein said separation unit is a gravimetrical-based and/or momentum-based separation and/or centrifugal-based separation. 
     
     
         14 . The iron fuel boiler process according to  claim 1 , further comprising a step of cooling down the separated iron oxide particles to a temperature of below 180° C.