A method for heating a blast furnace stove includes combusting fuel in a combustion chamber in the stove, providing combustion gases from the combustion chamber to heat refractory material in the stove, recirculating exhausted combustion gases into the combustion chamber, enriching the combustion chamber with oxygen sufficient for maintaining combustion in the combustion chamber without damaging the refractory material in the stove.

A process for producing an anti-erosion coating on an inner or outer metal wall of a chamber of a fluid catalytic cracking unit, comprising: (i) the shaping of a honeycomb metal anchoring structure, said anchoring structure being formed from a plurality of strips connected in pairs by joining assembly portions of these strips so as to form a plurality of cells between two adjacent strips, (ii) the fastening of said anchoring structure by welding to said metal wall, so that each cell of the anchoring structure is welded to the wall of the chamber at least at the junctions between the contiguous assembly portions of two adjacent strips, and (iii) the insertion of a composite material into the cells from the metal wall and at least up to the upper longitudinal edge of each strip.

Electric stove for heating a reducing gas, the electric stove including: a hollow metal shell body extending along a longitudinal direction; a refractory lining arranged on an inner surface portion of the shell body; a plurality of bricks arranged in adjacent layers extending along the longitudinal direction, where each brick includes a plurality of cavities extending straight along the longitudinal direction through the respective layer, where the cavities of adjacent layers are aligned to one another, whereby a plurality of channels for conducting the reducing gas is formed; and a plurality of heating wires for heating the reducing gas, wherein each heating wire has a diameter smaller than a diameter of a channel, and where each heating wire extends at least partially through at least one corresponding channel of the plurality of channels, such that when the electric stove is operated, a predefined heat amount is dissipated by each heating wire to a reducing gas flowing around the heating wire.

A method of direct reduction of iron (DRI) is disclosed, the method comprising generating metallic iron by removing oxygen from iron ore using a reducing gaseous mixture with excess carbon monoxide that produces an excess CO.sub.2 by-product is provided. CO.sub.2 by-product is optionally sequestered. A system for carrying out the method is also disclosed.

In various aspects, systems and methods are provided for operating a molten carbonate fuel cell assembly at increased power density. This can be accomplished in part by performing an effective amount of an endothermic reaction within the fuel cell stack in an integrated manner. This can allow for increased power density while still maintaining a desired temperature differential within the fuel cell assembly.

A flue gas treatment apparatus has a flue gas inlet, a treated gas outlet downstream of the flue gas inlet, and a gas flow path therebetween. The flue gas treatment apparatus comprises a particulate removal device. A first heater is downstream of the particulate removal device. The first heater heats the flue gas to a first treatment temperature. A first catalytic converter is downstream of the first heater for eliminating at least some CO and SO.sub.2 from the flue gas. A second heater is downstream of the first catalytic converter for heating the flue gas to a second treatment temperature. A second catalytic converter is downstream of the second heater for eliminating at least some NOx from the flue gas. At least a first fan forces the flue gas from the flue gas inlet to the treated gas outlet.

In various aspects, systems and methods are provided for integration of molten carbonate fuel cells with a Fischer-Tropsch synthesis process. The molten carbonate fuel cells can be integrated with a Fischer-Tropsch synthesis process in various manners, including providing synthesis gas for use in producing hydrocarbonaceous carbons. Additionally, integration of molten carbonate fuel cells with a Fischer-Tropsch synthesis process can facilitate further processing of vent streams or secondary product streams generated during the synthesis process.

The invention relates to a process for preparing ammonia gas and CO.sub.2 for urea synthesis. In the process of the invention, a process gas containing nitrogen, hydrogen and carbon dioxide as main components is produced from a metallurgical gas. The metallurgical gas consists of blast furnace gas, or contains blast furnace gas at least as a mixing component. The process gas is fractionated to give a gas stream containing the CO.sub.2 component and a gas mixture consisting primarily of N.sub.2 and H.sub.2. An ammonia gas suitable for the urea synthesis is produced from the gas mixture by means of ammonia synthesis. CO.sub.2 is branched off from the CO.sub.2-containing gas stream in a purity and amount suitable for the urea synthesis.

In various aspects, systems and methods are provided for operating molten carbonate fuel cells with processes for iron and/or steel production. The systems and methods can provide process improvements such as increased efficiency, reduction of carbon emissions per ton of product produced, or simplified capture of the carbon emissions as an integrated part of the system. The number of separate processes and the complexity of the overall production system can be reduced while providing flexibility in fuel feed stock and the various chemical, heat, and electrical outputs needed to power the processes.

Systems and methods are provided for processing metal sulfate compounds and sequestering CO.sub.2. These systems and processes involve one or more electrochemical cells for producing an alkali-containing catholyte and involve a CO.sub.2 absorption reactor operatively connected to the electrochemical cell and to a CO.sub.2 source. The CO.sub.2 absorption reactor receives the alkali-containing catholyte and CO.sub.2 gas for forming an alkaline carbonate solution. The alkaline carbonate solution is directed to a vessel where it reacts with an acidic sulfate solution comprising metal ions resulting in precipitation of solid metal carbonate compounds. The acidic sulfate solution may comprise sulfide leachates from acid mine drainage, sulfide mine tailings and/or reacted pyrite concentrate. The acidic sulfate solution may be circulated through an optional SO.sub.2 reduction reactor prior to reaction in the vessel. The SO.sub.2 reduction reactor reduces trivalent metal compounds present in the acidic sulfate solution to divalent metal compounds.