Baffle Wall Flow Separation in Cement Kiln Chlorine Bypass
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional cement plants face challenges in efficiently reducing chlorine concentration in the kiln due to contamination from calciner exhaust gas low in chlorine concentration, leading to increased heat loss and manufacturing costs when attempting to extract a part of kiln exhaust gas high in chlorine concentration.
Innovation Solution
A baffle wall is formed on the lower face of the calciner's exhaust duct at an inclination angle of 20 to 60° relative to the horizontal plane, with a spacing that maintains an average flow rate of 15 to 35 m/s between the baffle wall and the opposite wall plane, preventing calciner exhaust gas from contaminating the kiln inlet and allowing exclusive extraction of high-chlorine kiln exhaust gas by the chlorine bypass apparatus.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a part of kiln exhaust gas high in chlorine concentration is extracted by the chlorine bypass apparatus, then chlorine concentration in the kiln is reduced, but calciner exhaust gas low in chlorine concentration contaminates the extraction stream, reducing extraction efficiency
Solution Approach 1:
The exhaust gas flow path is segmented into distinct regions using a baffle wall that separates calciner exhaust gas flow from kiln exhaust gas flow. This segmentation ensures that only kiln exhaust gas high in chlorine concentration is extracted by the chlorine bypass apparatus, while calciner exhaust gas low in chlorine concentration is directed elsewhere, thereby improving extraction efficiency
Solution Approach 2:
The harmful calciner exhaust gas flow is extracted and removed from the potential contamination path by directing it through a separate flow path using the baffle wall configuration. This allows the chlorine bypass apparatus to selectively extract only the chlorine-rich kiln exhaust gas without contamination from calciner exhaust gas
2Quantity of substance
If exhaust gas extraction is increased to reduce chlorine concentration, then chlorine removal effectiveness improves, but heat loss increases and manufacturing costs rise
Solution Approach 1:
The baffle wall creates localized flow patterns that concentrate the extraction of chlorine-rich kiln exhaust gas in a specific region, while allowing calciner exhaust gas to follow a different path. This local quality differentiation enables effective chlorine removal with minimal heat loss by extracting only the necessary portion of exhaust gas
3Quantity of substance
If the gas extracting pipe is positioned to extract kiln exhaust gas, then chlorine concentration reduction is achieved, but calciner exhaust gas may contaminate the extraction stream
Solution Approach 1:
The baffle wall acts as an intermediary structure that guides and separates different exhaust gas flows. It mediates between the calciner exhaust gas flow and the kiln exhaust gas flow, ensuring that the gas extracting pipe extracts only kiln exhaust gas while preventing contamination from calciner exhaust gas
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 configuration effectively reduces chlorine concentration in the cement kiln by preventing calciner exhaust gas contamination and optimizing exhaust gas flow, minimizing heat loss and maintaining operational efficiency.
Implementation Method 1
a baffle wall protruding toward the pipe inclination part side on a lower face of the exhaust duct of the calciner at an inclination angle within a range of 20 to 60° with respect to a horizontal plane is formed
Implementation Method 2
a gas extracting pipe 11 which is connected to the exhaust gas pipe 9 from the kiln inlet part 2 and picks out and cools a part of the exhaust gas
Implementation Method 3
the chlorine component contained in the exhaust gas results in its transfer again to the cement raw material side
Data Source
AI summary
There is provided a cement plant including a chlorine bypass apparatus capable of efficiently reducing the chlorine concentration in a cement kiln due to exhaust gas extraction by a small amount, by preventing calciner exhaust gas low in chlorine concentration from contamination and extracting a part of kiln exhaust gas high in chlorine concentration. In the invention, a baffle wall 20 which protrudes, on a lower face 16a of an exhaust duct 16 of a calciner connected to the pipe inclination part 14 of an exhaust gas pipe 9 rising from a kiln inlet part 2 of a cement kiln 1, toward a pipe inclination part 14 side at an inclination angle α within a range of 20 to 60° relative to the horizontal plane, and a spacing between a lower end edge 20a of the baffle wall and an opposite wall plane 14a of the pipe inclination part is configured such that an average flow rate of the exhaust gas between the both falls within a range of 15 to 35 m/s.