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.
Particulate Emissions from Hydrogen Diesel Fuelled CI Engines
Compression ignition engines are much-celebrated power plants for both heavy transport and stationary applications, owing to their high thermal efficiency and low-end torque. However, CI engines are infamous for emission of black smoke mostly composed of carbon soot particulates. These soot particulates are a complex agglomeration of carbonaceous materials, volatile organic compounds (VOC) and trace heavy metals. Moreover, the soot particulates are reported to be associated with numerous hazards like impaired human organ functionality, climate change and visibility. Attempts have been made to reduce the soot emissions using diesel particulate filters (DPF) and other catalyst-based after-treatment technologies. However, life and performance efficiency of these measures remain questionable. This chapter aims to report the influence of hydrogen addition in a diesel engine on the particulate formation. The researchers have concluded that the primary pathway for PM formation in diesel engines is through hydrogen abstraction acetylene addition (HACA) mechanism, where a polyaromatic hydrocarbon (PAH) acts as a precursor to soot formation. The literature reports that hydrogen presence in the combustion chamber can deteriorate the formation of PM by interfering with HACA mechanism. Considering PM size and number are essential emission control parameters in vehicular emission norms throughout the world, and it is highly imperative to critically evaluate the potential of hydrogen in the reduction of PM size and number. Therefore, the chapter discusses in detail the effect of hydrogen enhancement in a dual-fuel engine. Further, attempting to critically present the hydrogen's influence on particulate modes, distribution and morphology.
Taphonomy of Isisfordia duncani specimens from the Lower Cretaceous (upper Albian) portion of the Winton Formation, Isisford, central-west Queensland
Taphonomic analysis of fossil material can benefit from including the results of actualistic decay experiments. This is crucial in determining the autochthony or allochthony of fossils of juvenile and adult Isisfordia duncani, a basal eusuchian from the Lower Cretaceous (upper Albian) distal-fluvial-deltaic lower Winton Formation near Isisford. The taphonomic characteristics of the I. duncani fossils were documented using a combination of traditional taphonomic analysis alongside already published actualistic decay data from juvenile Crocodylus porosus carcasses. We found that the I. duncani holotype, paratypes and referred specimens show little signs of weathering and no signs of abrasion. Disarticulated skeletal elements are often found in close proximity to the rest of the otherwise articulated skeleton. The isolated and disarticulated skeletal elements identified, commonly cranial, maxillary and mandibular elements, are typical of lag deposits. The holotype QM F36211 and paratype QM F34642 were classified as autochthonous, and the remaining I. duncani paratypes and referred specimens are parautochthonous. We propose that I. duncani inhabited upper and lower delta plains near the Eromanga Sea in life. Their carcasses were buried in sediment-laden floodwaters in delta plain overbank and distributary channel deposits. Future studies should refer to I. duncani as a brackish water tolerant species.