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An analyzer for real-time measure of sulfur compounds in vehicle exhaust gas has been developed utilizing the Ultra Violet Fluorescence (UVF) detection technology. This analyzer measures Total Sulfur (TS) including sulfates in PM. For detecting sulfur components as TS, sample gas is introduced into two combustion furnaces. The TS measurement by the UVF analyzer is considered to be applicable to real-time oil consumption test with sulfur tracing method, because it has high sensitivity and quick response. In this study, the UVF method is evaluated in detail based on the vehicle emission test results.

Recently, after-treatment techniques for diesel engine emission reduction have made a remarkable progress. Owing to new techniques such as the diesel particulate filter (DPF), the total amount of particulate matter (PM) collected on filter is rapidly reducing. It is significantly important for an engine operation to control the amount of PM or PM component ratio for high efficient after-treatment operation. Though a conventional gravimetric method is required by regulations, an alternative method, a combustion method, is focused on because of its simple and quick measurement. However it turned out that the combustion method has some difficulties to measure the low mass PM below 0.5mg. Then improvement methods were considered in this paper. Finally the modified instrument showed good correlation with gravimetric results below 0.5mg.

Since the introduction of Euro IV legislation [1, 2], Selective Catalytic Reduction (SCR) technology using liquid urea injection is (one of) the primary methods for NOx reduction in many applications. Ammonia (NH3) is the reagent and key element for the SCR system and its control calibration to meet all operational requirements. TNO and Horiba are highly motivated to facilitate a correct interpretation and use of emissions measurement data. Different hypotheses were defined to investigate the impact of temperatures and flow rates on urea decomposition. These parameters are known to strongly affect the urea decomposition process, and thus, the formation of NH3. During a test campaign, different SCR catalyst feed gas conditions (mass flow, temperature, species and dosing quantities) were applied. Three Horiba FTIR gas analyzers were installed to simultaneously sample either all upstream or all downstream of the SCR brick. Both steady-state and dynamic responses were evaluated.

Nitrous oxide (N₂O) emission reduction has gained large prominence recently due to its contribution to the climate change as a greenhouse gas. The United States Environment Protection Agency (US-EPA) together with the United States Department of Transport (DOT) has already regulated the N₂O emissions from light-duty vehicles (LDV) to 0.010 g/mile. For LDV, N₂O measurement should be done from sample storage bags over the light-duty FTP drive cycles. N₂O emission standard of 0.10 g/bhp-hr for heavy-duty engines (HDE) is also finalized. The final N₂O standard becomes effective in 2014 model year for diesel engines. Usually raw or diluted exhaust is measured for HDE emission testing. Therefore, an analyzer capable of measuring N₂O from bag and from diluted sample continuously is required to support both LDV and HDE regulations.

Recently, after-treatment techniques for diesel engine emission have made remarkable progress with the development of suitable De-NOx catalysts. The urea-injection SCR system is one of the candidates for a high efficiency De-NOx method for diesel engine emissions. This system reduces NOx through a reaction with ammonia (NH3) that is generated from injected urea. In this system, it is very important to control the amount and timing of the urea injection so as to minimize the NH3 gas slip. Therefore, NH3 gas measurement is becoming important during the development of NOx after-treatment systems even though NH3 is not a target component of the current emission regulations. In this paper, a new NH3 gas analyzer utilizing a chemi-luminescence detection (CLD) method has been developed. The new NH3 analyzer consists of dual detectors (DCLDs) and a furnace for a NH3 oxidization catalyst. Real-time concentration of NH3 can be calculated from the difference of NOx readings of two detectors.