Method for operating a top gas recycling blast furnace installation
AssigneeL'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
InventorMichael Grant
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Abstract
Method of operating a blast furnace installation comprising a top gas recycle blast furnace and hot stones, whereby a hydrocarbon containing fuel is transformed into a transformed gas stream consisting mainly of CO and H2 and substantially devoid of hydrocarbon, whereby a low-heating-value gaseous fuel is generated comprising a mixture of the transformed gas with a portion of the CO2-rich tail gas obtained by decarbonatation of the blast furnace gas, and whereby the low-heating-value fuel is used to heat the hot furnace gas is heated before being injected into the blast-furnace.
Claims16
A method of operating a blast furnace installation comprising a top gas recycle blast furnace generating blast furnace gas, comprising the steps of:
- decarbonating the blast furnace gas so as to obtain a CO2-enriched rich tail gas stream and a decarbonated blast furnace gas stream containing not more than 3% vol CO2;
- transforming a hydrocarbon-containing gaseous fuel not generated by the blast furnace to generate a transformed gas stream containing at least 70% vol of CO and H2 in total and at most 7% vol of hydrocarbon;
- producing a low-heating-value gaseous fuel having a heating value of from 2.8 to 7.0 MJ/Nm3 and containing (i) a portion of the tail gas stream and (ii) at least a first portion of the transformed gas stream and using said low-heating-value gaseous fuel for heating hot stoves;
- heating at least 70% vol of the decarbonated blast furnace gas stream in the hot stoves to a temperature between 700° C. and 1300° C. to generate heated decarbonated blast furnace gas;
- and
- injecting the heated decarbonated blast furnace gas into the blast furnace.
Dependencies are inferred from the claim text.