Process and installation for producing substitute gas
AssigneeSiemens Vai Metals Technologies GmbH
InventorsRobert Millner, Jan-Friedemann Plaul, Kurt Wieder
Life of this patent
Estimating the term…
Abstract
A process and an installation for reducing particulate material containing iron oxide are shown, wherein the material containing iron oxide is at least partially reduced with reducing gas in a reducing zone and the waste gas produced during the reduction is drawn off and subsequently subjected to CO2 cleaning in a CO2 separating device (1), in which a tail gas containing CO2 is separated. The tail gas is subjected to combustion and subsequent dewatering in a dewatering device (5), the substitute gas thereby formed being used as a substitute for inert gas.
Claims16
A process for reducing particulate material containing iron oxide, comprising:
- reducing the material containing iron oxide at least partially with reducing gas in a reducing zone,
- drawing off the gas produced during the reduction as waste gas and subsequently subjected the gas to CO2 separation, in which a tail gas containing CO2 is separated,
- in order to balance out fluctuations in the amount and calorific value, temporarily storing the tail gas in a gas accumulator,
- mixing the tail gas with a gas containing oxygen or pure oxygen,
- combusting the mixed tail gas in a burner system, thereby forming a substitute gas, the substitute gas being used after dewatering as a substitute for inert gas or instead of nitrogen, wherein at least part of the substitute gas being mixed with the gas containing oxygen and being returned to the burner system after at least one of dewatering and compression for setting the combustion temperature during the combustion of the tail gas.
An installation for reducing particulate material containing iron oxide, with a reduction unit, in which the material containing iron oxide is at least partially reduced by means of a reducing gas and the reducing gas is drawn off as top gas, and with a CO2 separating device for separating CO2 from the top gas, thereby forming a tail gas containing CO2, wherein there are provided a burner system for mixing the tail gas with a gas containing oxygen or pure oxygen, and optionally a gas accumulator for temporarily storing and homogenizing the tail gas before it is mixed with the gas containing oxygen, and a combustion chamber, into which these gases can be introduced and combusted, thereby forming a substitute gas, and discharged by way of a substitute-gas discharge line, wherein there is provided a cooling or waste-heat recovering device including a dewatering device for separating water from the substitute gas, so that a substitute for inert gas or for nitrogen is formed, wherein a return line is provided for returning part of the dewatered substitute gas and for introducing it into the burner system after admixing gas containing oxygen for setting the combustion temperature during the combustion of the tail gas, this line branching off from the substitute gas line downstream of the dewatering device.
Dependencies are inferred from the claim text.