Biodiesel from Crude Tall Oil and Its NOx and Aldehydes Emissions in a Diesel Engine Fueled by Biodiesel-Diesel Blends with Water Emulsions

Murari Mohon Roy,Md Shariful Islam,Md Nur Alam

doi:10.3390/pr9010126

Abstract

Using biodiesel in diesel engines is beneficial for reducing emissions of carbon monoxide (CO), hydrocarbons (HC) and particulate matters (PM). Biodiesel is usually produced from vegetable oils or animal fats. When produced from plant oil or woody plant sources, biodiesel can reduce a significant amount of carbon dioxide on a life cycle basis. The objective of this study is to produce biodiesel from a non-conventional woody plant source that is, crude tall oil, which is a dark brown viscous liquid extracted and processed in wood pulping plants. It contains a high percentage of fatty acids. From raw crude tall oil, tall oil fatty acids were separated and were successfully used for the production of biodiesel in this study. Although biodiesel produces lower CO, HC and PM than petroleum diesel fuel, it produces higher oxides of nitrogen (NOx) emissions in diesel engines. Water emulsifications of diesel-biodiesel blends are investigated in a direct injection (DI) diesel engine in this work to understand their potential for NOx reduction. When using 10% water in the emulsions, NOx was reduced by nearly 15%. In aldehyde emissions, B100 showed 35% lower aldehydes and B100 with 10% water emulsion produced nearly 90% lower aldehydes than diesel fuel—a substantial reduction. Therefore, this study accomplished the desired goal of producing biodiesel from a non-conventional source, which satisfies ASTM biodiesel standard and results in lower NOx and aldehydes emissions with water emulsifications of diesel-biodiesel blends in a diesel engine compared to that of diesel fuel.

Highlights

The study concluded that pure biodiesel can reduce 70% of hydrocarbons (HC) emissions and 50% of particulate matters (PMs) and carbon monoxide (CO) emissions compared to conventional diesel fuel
It was noticed that heating value decreased 4.86% and 9%, with 5% and 10% of water emulsions, respectively and that density and viscosity gradual increased when adding more water in the emulsion
Fatty acids extracted from crude tall oil were utilized for the production of biodiesel through acidic esterification reaction in this study

Summary

Introduction

Use of biodiesel in diesel engines can significantly reduce GHG (78%) on a life cycle basis [1]. An investigation on the impacts of biodiesel on exhaust emissions was conducted by the United States. The study concluded that pure biodiesel can reduce 70% of hydrocarbons (HC) emissions and 50% of particulate matters (PMs) and carbon monoxide (CO) emissions compared to conventional diesel fuel. Many other investigations revealed that the use of biodiesel can result in a substantial reduction in PM, HC and CO emissions [3,4,5,6]. In a recent study [10], it was reported that a minor modification to engine parameters, such as compression ratio, injection timing and injection pressure with a binary mixture of 70% amla seed oil biodiesel and

Objectives

Methods

Results

Conclusion