Regeneration Of Diesel Particulate Filters With Hydrogen Rich Gas
The options for the regeneration of a Diesel Particulate Filter (DPF) using hydrogen rich gas are investigated. The advantages of using hydrogen rich gas for this purpose are described. The system requirements for such a system are also evaluated. The use of a plasmatron fuel converter for the onboard generation of hydrogen rich gas from diesel fuel is discussed. The advantages of homogeneous, non-catalytic reforming by the plasmatron fuel converter are described. Finally, the effect of homogeneous combustion of the hydrogen rich gas in the exhaust (upstream from the DPF) is investigated.
Visualization of Combustion Phenomena in Regeneration of Diesel Particulate Filter
Combustion phenomena in the regeneration of a diesel particulate filter (DPF) were clarified through a visualization experiment, using a half-cylindrical wall-flow DPF covered by a quartz glass plate. At a constant oxygen concentration (8.5% and 10% in the current study) of a working gas used for regeneration, in the cases of large particulate masses and high working gas temperatures, the particulate matter trapped on the filter surface is burned in a narrow reaction zone which can be observed as a high brightness zone moving slowly toward the downstream side. Just after the reaction zone passes, a sharp temperature peak is detected and there remains no particulate matter on the filter surface. Furthermore, the particulate matter is ignited first around the middle of the DPF, and then, the reaction zone propagates toward both the upstream and the downstream sides. On the other hand, in cases of small particulate masses and/or low working gas temperatures (but higher than 600°C), no such bright reaction zone is seen; however, it was observed that with time the particulate matter disappeared uniformly on the entire filter surface. These regeneration patterns can be summarized as separate and distinct reaction patterns in a reaction diagram consisting of the particulate mass and the inlet temperature of the working gas.
Techno-economic analysis of chemical looping combustion with humid air turbine power cycle
Abstract Power generation from fossil fuel-fired power plant is the largest single source of CO2 emission. CO2 emission contributes to climate change. On the other hand, renewable energy is hindered by complex constraints in dealing with large scale application and high price. Power generation from fossil fuels with CO2 capture is therefore necessary to meet the increasing energy demand, and reduce the emission of CO2. This paper presents a process simulation and economic analysis of the chemical looping combustion (CLC) integrated with humid air turbine (HAT) cycle for natural gas-fired power plant with CO2 capture. The study shows that the CLC–HAT including CO2 capture has a thermal efficiency of 57% at oxidizing temperature of 1200 °C and reducer inlet temperature of 530 °C. The economic evaluation shows that the 50 MWth plant with a projected lifetime of 30 years will have a payback period of 7 years and 6 years for conventional HAT and CLC–HAT cycles respectively. The analysis indicates that CLC–HAT process has a high potential to be commercialised.