Oxyfuel clinker production with special oxygen addition
AssigneesThyssenkrupp Industrial Solutions AG, Vicat
InventorsJost Lemke, Eike Willms
Life of this patent
Estimating the term…
Abstract
Processes and plants for producing cement clinker, in which an oxygen-containing gas having a proportion of 15% by volume or less of nitrogen and a proportion of 50% by volume or more of oxygen is conveyed from a first section of the cooler directly adjoining the top of the furnace into the rotary furnace and is optionally additionally conveyed to the calciner, and where the total gas streams fed in to the combustion processes consist to an extent of more than 50% by volume (preferably more than 85% by volume) of oxygen.
Claims18
A method for producing cement clinker, comprising:
- preheating a starting material to a calcination temperature,
- performing calcination of the preheated starting material in a calciner,
- firing, in a rotary furnace, the calcined starting material to form cement clinker,
- cooling the cement clinker in a cooler, and
- feeding an oxygen-containing gas having a proportion of 15% by volume or less of nitrogen and a proportion of 50% by volume or more of oxygen into a first section of the cooler, the first section of the cooler directly adjoining a top portion of the rotary furnace, and from the first section of the cooler into the rotary furnace,
- wherein the total gas streams fed to the cooler consist of more than 75% by volume of oxygen,
- the introduction of the oxygen-containing gas is set so that there is an excess of oxygen at a main burner and residual amounts of the oxygen-containing gas are permitted to enter the calciner for combustion, and a proportion of oxygen in the oxygen-containing gas fed from the cooler into the rotary furnace is the same as the proportion of oxygen in the oxygen-containing gas fed to the cooler.
A plant for producing cement clinker, comprising:
- a preheater,
- a calciner,
- a rotary furnace, and
- a clinker cooler,
- wherein the plant has, at a section of the cooler directly adjoining a top of the rotary furnace, a device for feeding gas from the cooler to the rotary furnace, the device configured to feed a gas having a proportion of 15% by volume or less of nitrogen and a proportion of 50% by volume or more of oxygen such that there is an excess of oxygen at a main burner and residual amounts of oxygen are conveyed into the calciner,
- wherein the plant is configured for feeding gas streams which in total consist to an extent of more than 75% by volume of oxygen to the cooler,
- wherein at least one of:
- the plant is free of a tertiary air supply to the calciner, or
- the plant is free of means separate from the rotary furnace for supplying enriched oxygen to the calciner.
A method for producing cement clinker, comprising:
- preheating a starting material to a calcination temperature;
- performing calcination of the preheated starting material in a calciner;
- firing, in a rotary furnace, the calcined starting material to form cement clinker;
- cooling the cement clinker in a cooler;
- feeding an oxygen-containing gas having a proportion of 15% by volume or less of nitrogen and a proportion of 50% by volume or more of oxygen into a first section of the cooler, the first section of the cooler directly adjoining a top portion of the rotary furnace, and from the first section of the cooler into the rotary furnace;
- and
- limiting fuel energy that is introduced into the rotary furnace to less than 33% of fuel energy necessary for clinkering,
- wherein the total gas streams fed to the cooler consist of more than 75% by volume of oxygen,
- the introduction of the oxygen-containing gas is set so that there is an excess of oxygen at a main burner, so that residual amounts of the oxygen-containing gas are permitted to enter the calciner for combustion, and a proportion of oxygen in the oxygen-containing gas fed from the cooler into the rotary furnace is the same as the proportion of oxygen in the oxygen-containing gas fed to the cooler.
Dependencies are inferred from the claim text.