Exhaust Emissions and Physicochemical Properties of Hydrotreated Used Cooking Oils in Blends with Diesel Fuel

Iraklis Zahos-Siagos,Dimitrios Karonis

doi:10.1155/2018/4308178

Iraklis Zahos-Siagos, Dimitrios Karonis

Open Access

https://doi.org/10.1155/2018/4308178

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Abstract

Hydroprocessing of liquid biomass is a promising technology for the production of “second generation” renewable fuels to be used in transportation. Its products, normal paraffins, can be further hydrotreated for isomerization in order to improve their cold flow properties. The final product, usually referred to as “paraffinic diesel,” is a high cetane number, clean burning biofuel which is rapidly gaining popularity among researchers and the industry. Nevertheless, the costly isomerization step can be omitted if normal paraffins are to be directly mixed with conventional diesel in low concentrations. In this work, nonisomerized paraffinic diesel produced through hydrotreating of used cooking oil (hydrotreated used cooking oil (HUCO)) has been used in 4 blends (up to 40% v/v) with conventional diesel fuel. The blends’ properties have been assessed comparatively to European EN 590 and EN 15940 standards (concerning conventional automotive diesel fuels and paraffinic diesel fuels from synthesis or hydrotreatment, resp.). Furthermore, the HUCO blends have been used in a standard stationary diesel engine-generator set. The blends have been considered as “drop-in replacements” for standard diesel fuel. As such, no engine modifications took place whatsoever. The engine performance and exhaust emissions of steady-state operation have been examined in comparison with engine operation with the baseline conventional diesel fuel.

Highlights

Compression ignition engines have been undoubtedly the dominant powertrain in transportation sector’s medium- to heavy-duty applications for decades
A first assessment of HUCO as a blending component with ultralow sulfur diesel (ULSD) took place regarding the physicochemical properties of the 2 fuels and the 4 blends created
HUCO measured properties were evaluated comparatively to EN 15940 standard for “class A” paraffinic diesel fuels from synthesis or hydrotreatment. e properties of ULSD, H10, H20, H30, and H40 samples were evaluated comparatively to standard EN 590 for automotive diesel fuels which is currently in effect. Both ULSD and HUCO fuels were found to be in compliance with their respective standards, EN 590 and EN 15940

Summary

Introduction

Compression ignition engines (i.e., diesel engines) have been undoubtedly the dominant powertrain in transportation sector’s medium- to heavy-duty applications (trucks, buses, and marine propulsion) for decades now. Catalytic hydroprocessing has been a well-established process in the petrochemical industry for over a century, and it has been examined for conversion of vegetable oils since the early 1990s [7, 14] It can be employed for various purposes such as heteroatom (sulfur, nitrogen, oxygen, and metals) removal, saturation of olefins and aromatics, isomerization, and cracking. Is step, adds an extra cost to overall biofuel production not to mention that there are cases where it may not be needed (e.g., when paraffinic diesel is to be mixed in relatively small proportions with conventional diesel, resulting in negligible deterioration of final blend’s cold flow properties) Another use for nonisomerized paraffinic diesel could be the upgrade of lowquality gasoil fuels through strategic blending [14, 23].

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Exhaust Emissions Experimental Setup and Procedures

C15 C16 C17 C18

Results and Discussion

H30 H40 HUCO