Method and system for producing pig iron or fluid steel pre-products

Abstract

A method and a plant for the production of pig iron or liquid steel semi-finished products are shown, metal oxide-containing batch materials and, if appropriate, aggregates being at least partially reduced in a reduction zone by a reduction gas, subsequently being introduced into a smelting zone and being smelted along with the supply of carbon carriers and oxygen-containing gas and along with the formation of the reduction gas. The reduction gas formed in the smelting zone is supplied to the reduction zone, reacted there and drawn off as export gas, CO 2 is separated from the export gas, and a product gas is formed which is utilized for the introduction of pulverulent carbon carriers into the smelting zone.

What is claimed is: 
     
         1 . A plant for the production of pig iron or liquid steel semi-finished products, with a reduction assembly, in which metal-containing batch materials and, if appropriate, aggregates can be at least partially reduced by means of a reduction gas, and with a smelting assembly, into which the at least partially reduced batch materials or the aggregates can be introduced and smelted along with the supply of carbon carriers and oxygen-containing gas and along with the formation of the reduction gas, the formed reduction gas being capable of being supplied to the reduction assembly, reacted there and drawn off, if appropriate after purification, as export gas, wherein a CO 2  separation device for separating CO 2  from the export gas and for forming a product gas is provided, the product gas being connected via a product gas line to at least one introduction device for the introduction or injection, of pulverulent carbon carriers into the smelting assembly, wherein the introduction device has at least one mixing chamber for mixing the product gas with pulverulent carbon carriers and conveying gas, the mixing chamber being connected to the product gas line and to a conveying line for the inward conveyance of the pulverulent carbon carriers. 
     
     
         2 . The plant according to  claim 1 , wherein the batch materials contain iron-oxide, the lumpy carbon carriers are at least one of coke and coal, and the conveying gas is nitrogen. 
     
     
         3 . The plant according to  claim 1 , wherein the introduction device has an introduction line which connects the mixing chamber to at least one nozzle. 
     
     
         4 . The plant according to  claim 1 , wherein the introduction device has a supply line for the introduction of oxygen-containing gas. 
     
     
         5 . The plant according to  claim 4 , wherein the supply line and the introduction line are merged in the nozzle. 
     
     
         6 . The plant according to  claim 3 , wherein the nozzle is a tuyere of a blast furnace or an oxygen nozzle of a smelting assembly. 
     
     
         7 . The plant according to  claim 1 , wherein the reduction assembly is designed as the shaft of a blast furnace or as a reduction shaft or as a fluidized bed assembly or as a group of series-connected fluidized bed assemblies, and the smelting assembly is designed as the lower part of a blast furnace or as a melt-down gasifier. 
     
     
         8 . The plant according to  claim 1 , wherein a purification device is provided in a top gas outlet line for the outlet of reduction gas from the reduction assembly. 
     
     
         9 . The plant according to  claim 8 , wherein the purification device is connected by means of an export gas line to the CO 2  separation device, wherein at least one of a compressor and at least one cooler being arranged in the export gas line. 
     
     
         10 . The plant according to  claim 1 , wherein a heating device for the heating of product gas before the introduction of the latter into at least one of the reduction assembly and into the smelting assembly is provided, the heating device being capable of being heated as a result of the at least partial combustion of at least one of tail gas and of export gas. 
     
     
         11 . The plant according to  claim 8 , wherein the purification device is at least one of a dry purification and wet purification device.