Emissions Reduction of Regulated and Unregulated Hydrocarbon, Gases in Gasoline Bi-mode SI/HCCI Engine by TWC Converter

Hasan Aoand Abu Jrai A

doi:10.4172/2168-9873.1000224

Abstract

A specific case of HCCI is gasoline fuelled HCCI. It is attractive due to the simplicity of implementing such a technology into existing SI engines as well as the existing fuelling infrastructure. Lean and highly diluted homogeneous charge compression ignition HCCI engines offer great potential in improving vehicle fuel economy and contribute in reducing CO2 emissions. Gasoline is a complicated mixture of many different hydrocarbons which results in rather poor auto-ignition properties. Hydrocarbons and CO emissions from HCCI engines can be higher than those from spark ignition (SI) engines, especially at low engine load when the EGR rate or the residual gas required to control NOx emission are elevated. Toxic chemicals emitted by SI engines, Carbonyl compounds and poly aromatic hydrocarbons PAH generated by V6 (SI/HCCI) gasoline engine especially in HCCI mode. A qualitative and quantitative analysis of hydrocarbon compounds, alkenes. Alkanes, aromatics and aldehydes was analysed before and after catalyst, alkanes, alkenes and aromatic were conducted using Gas Chromatography-Mass Spectrometry (GC-MS) apparatuses. Aldehydes were conducted using High Performance liquid chromatography (HPLC) on reversed phase. HPLC system, although, bi-functional after treatment, the device will be required to control the regulated and unregulated hydrocarbon, CO, and NOx emissions under lean and stoichiometric (oxygen free) engine operating conditions. This paper describes studies on the regulated and unregulated hydrocarbons, NOx, and CO emissions coming out of HCC/SI gasoline engine. Comparative study of catalyst performance will be analysed under HCCI stoichiometric and SI operation under different engine loads, analysis indicate that, the HC and CO emissions reduction over the prototype catalyst was in the range of 90-95% while the maximum NOx emissions reduction under lean engine operating conditions was in the range of 35-55%. The catalytic converter showed an excellent efficiency of eliminating unregulated hydrocarbons (alkenes, alkanes, and aromatics) and aldehydes compounds; achieved reduction efficiency was up to 92%.

Highlights

Homogeneous Charge Compression Ignition (HCCI) engine is an alternative piston-engine combustion process which can deliver high engine efficiency comparable with those of compression ignition (CI) engines
It has been proposed that the engine technology employing HCCI will have dual mode combustion systems, where spark ignition (SI) or CI combustion is in use together with HCCI
Increasing engine load from 3-4 bar improves HC and CO oxidation which leads to significant reduction of HC and CO emissions, on the other hand the opposite trend seen in the case of NOx emission when the engine load was increased

Summary

Introduction

Homogeneous Charge Compression Ignition (HCCI) engine is an alternative piston-engine combustion process which can deliver high engine efficiency comparable with those of compression ignition (CI) engines. Hydrocarbon and carbon monoxide levels of HCCI engines vary between experimental conditions Though they are found to be similar or higher than those of SI engines and both CO and HC emissions are increase at light loads. The mass distribution of these species in the exhaust is a function of the engine design, fuel composition, and the engine operation conditions Another cause of excessive HC emissions is related to combustion chamber deposits. This is the major source of HC emissions from four-stroke engines This manuscripts presents study on a new catalytic converter design, aiming to control regulated and unregulated hydrocarbons, CO and NOx emissions under stoichiometric, HCCI/SI engine operation and different engine loads.

Experimental Procedure

Results and Discussion

Conclusions