Cement Clinker Chloride Bypass Gas Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The chloride bypass exhaust gas in cement clinker manufacturing has a reduced oxygen content when used for calcination and combustion, making it difficult to comply with emission limits, and cooling it with fresh air increases treatment costs and reduces energy recuperation.
Innovation Solution
Using previously cooled chloride bypass exhaust gas and/or main kiln exhaust gas as a coolant instead of air to cool the chloride bypass gas, followed by heat recovery through a heat exchanger, and implementing selective catalytic reduction and oxidation catalysts to enhance energy efficiency and emissions control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If chloride bypass exhaust gas is used for calcination and combustion, then oxygen content is reduced, but emission limits cannot be complied with
Solution Approach 1:
The exhaust gas treatment process is segmented into multiple stages: first cooling step, deducting step, and second cooling step with heat recovery. This segmentation allows each stage to address specific issues independently, enabling oxygen removal while maintaining emission compliance through controlled processing at different temperature levels.
Solution Approach 2:
The patent applies parameter changes by controlling temperature at different stages: cooling the bypass gas to condense chlorides, then reheating to burn off carbon, and final cooling for heat recovery. These temperature parameter changes transform the exhaust gas composition to meet emission limits while preserving oxygen for combustion processes.
2Temperature
If fresh air is used to cool chloride bypass gas, then cooling effect is achieved, but treatment costs increase and energy recuperation is reduced
Solution Approach 1:
The system implements feedback by using the cooled exhaust gas from the second cooling step as the cooling medium in the first cooling step. This creates a closed-loop heat exchange system where the cooling demand of the first stage is met by the thermal energy available in the second stage output, maximizing energy recuperation and eliminating the need for external fresh air cooling.
Solution Approach 2:
The exhaust gas cooling system serves itself by using its own cooled output to provide cooling for the earlier stage. The second cooling step's cooled gas automatically becomes the cooling medium for the first cooling step, creating a self-sufficient thermal management system that recovers energy internally without external energy input.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces the volume of exhaust gas, minimizes oxygen enrichment, and allows for compliance with emission limits while maximizing energy recuperation and reducing treatment costs.
Implementation Method 1
the bypass gas is cooled in a first cooling step by mixing it with a cooling gas
Implementation Method 2
The remaining heat may be recuperated by cooling the dedusted chloride bypass gas flow in a second cooling step by providing a thermal contact of the dedusted chloride bypass gas flow with at least one heat carrier fluid which is in turn heated
Data Source
AI summary
In methods of and/or plants for manufacturing cement clinker, the amount of chloride bypass exhaust gas 79 can be substantially decreased, when using previously cooled chloride bypass exhaust gas 81 and/or cooled kiln exhaust gas as coolant for the chloride bypass exhaust gas 39 prior to deducting the chloride bypass exhaust gas 39.