Ship Exhaust Purification System with Integrated Bypass Casing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional exhaust gas purification systems for ships face challenges in efficiently processing NOx emissions due to catalyst clogging and increased costs associated with separate bypass paths, particularly in narrow engine rooms and when dealing with multiple engines.
Innovation Solution
An integrated exhaust gas purification system with a combined casing that includes a main path and a bypass path, where a selective catalyst reduction device is housed close to the main path, and a path-switching member to direct exhaust gases between paths, along with a reducing agent injection system to ensure efficient NOx reduction and extended catalyst life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a separate bypass path is provided outside the purification casing, then exhaust gas can be diverted away from the NOx catalyst, but the piping distance increases and production costs rise
Solution Approach 1:
The patent integrates the bypass path inside the purification casing rather than providing it separately outside. The bypass passage is formed within the casing structure itself, merging the purification chamber and bypass route into a single integrated component. This eliminates the need for separate external piping, reducing both production costs and structural complexity while maintaining the ability to divert exhaust gas away from the catalyst when needed
2Reliability
If a separate bypass path is provided outside the purification casing, then exhaust gas can be diverted away from the NOx catalyst, but installation space is required separately from the purification casing
Solution Approach 1:
The bypass path is nested within the purification casing structure. The bypass passage is formed inside the casing that already houses the purification chamber, effectively utilizing the existing spatial envelope. This nesting approach allows the bypass functionality to be accommodated without requiring additional external installation space, making the system suitable for narrow engine rooms with limited space
3Productivity
If the NOx catalyst is exposed to exhaust gas during sailing in non-regulation marine areas, then the purification system can operate continuously, but the catalyst lifetime is reduced and running costs increase
Solution Approach 1:
The system employs a dynamic path-switching mechanism that can change the exhaust gas flow route based on operational conditions. A switching valve allows the system to dynamically select between directing exhaust gas through the purification path (when in regulation marine areas requiring NOx removal) or through the bypass path (when in non-regulation areas where purification is unnecessary). This dynamic adaptability ensures the catalyst is only exposed when needed, extending its lifetime while maintaining purification productivity when required
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 allows for efficient processing of exhaust gases, extends the life of the catalyst, reduces manufacturing and installation costs, and simplifies the exhaust structure by merging paths, making it suitable for ships with multiple engines and limited space.
Implementation Method 1
a selective catalyst reduction device which accelerates reduction of NOx existing in exhaust gas of the engine is accommodated in the combined casing
Implementation Method 2
the urea water is hydrolyzed by heat of exhaust gas and ammonia is produced, the ammonia as a reducing agent acts on NOx
Implementation Method 3
a path-switching member which switches exhaust gas moving directions between the main path and the bypass path is placed in a branched portion
Data Source
AI summary
An exhaust gas purification system includes, as an exhaust gas path of an engine to be mounted in a ship, a main path which is in communication with outside, a bypass path which branches off from a halfway portion of the main path, and a combined casing with which both the main path and the bypass path are in communication. A selective catalyst reduction device is accommodated in the combined casing at a location close to the main path. A path-switching member which switches exhaust gas moving direction is placed in a branched portion between the main path and the bypass path. A reducing agent injection body is placed in the main path between the path-switching member and the combined casing.