Design And Test Of Experimental System For Simulating Exhaust Gas From Marine Diesel Engine

Emissions from marine diesel engines contain large amounts of nitrogen oxides(NOx), sulfer oxides(SOx), carbon oxides(COx), particulate matter(PM) and other harmful substances causing serious air pollution, which has become one of the main sources of pollution. International Maritime Organization (IMO) has formulated strict exhaust emission regulations and dealing with ship exhaust gases is an important and urgent task at present. Nowadays, many domestic and foreign experts and scholars are studying the after-treatment technology of marine diesel engines (flue gas) emissions. However, the complicated components of marine exhaust, high temperature, unavailability of on-board measurement and some other reasons bring much inconvenience to the early-stage experiment on exploring new technology of exhaust emission treatment. Therefore, it is of great importance to build up a perfected and reliable marine exhaust gas simulation system for the development of marine exhaust gas processing technology.The author of this thesis firstly compares the various methods of standard gas distribution and selects the mass flow control method which meets the requirements in this system. Then, the author discusses the gas mixing ratio calculation of mass flow method. The author also designs the simulated exhaust gas system from the aspects of processes conception, designing requirements, components selection and so on, and introduces the overall composition and gas distribution operation of the system.For the complete simulated exhaust gas system, the author conducts a series of experiments for performance verification experiments, including air tightness test, gas delay-output characteristics test and simulation of marine exhaust gas of mono-component and multi-component gas mixture ratio test, and gas output stability test. The author analyzes a large number of simulated exhaust gas composition data which are measured by flue gas analyzers with the principles of mathematical statistics. The result of the experiments proves that the exhaust gas simulation system for marine diesel engine designed in this thesis has a gas distribution uncertainty lower than5%as well as a good output stability, which can meet the requirements of the study on the new treatment technology of exhaust gas emission from marine diesel engines under the laboratory condition.