main-content

This monograph focuses on methanol and its utilization in transportation sector, namely in spark ignition (SI) engines. The contents focus on methanol production and presents a variety of production technologies from different feedstocks. The potential of methanol utilization in transportation in SI engines is discussed, its challenges, limitations, aspects related to its utilization and current global use of methanol are also presented. The book also contains chapters related to pollutant formation and exhaust emissions from methanol fuelled SI engines, one chapter is focused specifically on formaldehyde emissions, which possesses one of the greatest challenges of methanol use in IC engines. Readers will learn about the production aspects of methanol, its potential as a sustainable fuel, its utilization in SI engine and the effect of methanol and its utilization techniques on engine performance, combustion, exhaust emissions, efficiency and other important parameters. This volume will be a useful guide for professionals, post-graduate students involved in alternative fuels, spark ignition engines, and environmental research.

### Introduction of Methanol: A Sustainable Transport Fuel for SI Engines

Abstract
Shortcoming of fossil energy resources and increasing energy demands lead to a search for alternative energy sources. The utilization of alcohol based fuels seems to be a suitable alternative for spark ignition (SI) engines. The most used alcohol fuels are methanol, ethanol, and butanol. Specific properties of these fuels predetermine them for mass utilization, especially in SI engines. The oxygen content of the alcohol fuels affects the harmful emission formation and combustion efficiency positively. On the other hand, their lower energy content means that in order to maintain the engine performance, it is necessary to increase the amount of fuel delivered to the engine, which may lead to construction modifications in the engine. Methanol is an important alternative fuel for SI engines and therefore this monograph is dedicated to this topic. This monograph focuses on the physical and chemical properties of methanol, utilization in SI engines, and the effect of methanol on formaldehyde emissions.
Avinash Kumar Agarwal, Hardikk Valera, Martin Pexa, Jakub Čedík

### Methanol as an Alternative Fuel in Internal Combustion Engine: Scope, Production, and Limitations

Abstract
In the present era, vehicles on road are increasing day by day and its demand is bouncing. The world’s fossil fuel reserves are limited so there is scope to have intensive research to develop and use non-fossil fuels in vehicles. Methanol is the best-suited candidate to fulfil this crisis. Methanol has lots of supporting characteristics to be used in the engine; lower production costs, high octane number, impressive cold working temperature, good emission characteristics, high latent heat of vapourization, enhancing thermal efficiency, high flame speed, low combustion temperature are a few of them. This fuel can be used directly and with blending with conventional fuel in engines. Methanol can be produced from a variety of feedstock such as coal, natural gas, CO2, biomass, etc. through various processes like reforming the gas with steam, production with methanotrophic Bacteria, gasification process, carbon dioxide hydrogenation, synthesis through Syngas, direct oxidation of methane, etc. Although methanol has many adaptive properties to be used as a fuel individual and with levels of blending however there are many challenges too with methanol used as a fuel; its toxicity, fire safety concern, low cetane number, lower heating value, higher kinematic viscosity, low lubricity, high corrosive in nature are a few of them. This chapter deals with various aspects from scopes to limitations of methanol to be used in Internal Combustion Engines.
Puneet Bansal, Ramnarayan Meena

### Methanol as a Low-Cost Alternative Fuel for the Reduction of Emissions

Abstract
Over the past years, there has been a dramatic increase in the regulatory requirements for low emissions from both new and existing utility boilers and gas turbines. Traditional methods of reducing NOx emissions, such as modification of the firing system and/or post-combustion treatment of the flue gas to remove NOx are very expensive. Hence, before the implementation of these expensive measures for emission reduction, it is desirable to evaluate all other low-cost alternatives. Fuel properties have a major influence on NOx formation during combustion. One of the attractive alternative fuels for combustion in utility boilers, gas turbines, and engines may be methanol. Existing experience has shown that with minor system modifications, methanol can easily be used as an alternative fuel that significantly decreases NOx and other harmful emissions. Besides that, methanol may be produced from CO2 which will allow reducing CO2 emission by extracting it from the flue gas flow of conventional utilities for methanol production and then further into clean electricity generation. On top of that, the additional advantage of methanol is it is a universal chemical and a fuel feedstock material, that is useful as both a chemical energy storage material and a substituting fossil raw material. Using methanol has become an important solution for emissions compliance to regulations due to its unique constituents and combustion characteristics. Methanol may be referred to as an enviro fuel. The clean burning characteristics of methanol are expected to lead to clean boiler pressure parts or turbine blades thus lowering maintenance compared to any other fuel oil burning. The experience gained by Israel Electric Corporation and Dor Chemicals with methanol burning and the usage of synthetic methanol to produce clean storage energy will be presented in this chapter.
Boris Chudnovsky, Alex Lazebnikov, Mordechai Reshef, Ilya Chatskiy

### Energy Analysis of Methanol Synthesis via Reverse Water-Gas Shift Reactor

Abstract
The growing energy demand and arousing environmental concerns are some of the major issues faced all over the globe. Excessive CO2 release has always been devastating the human ecosystem but in recent years historically high emission of CO2 from the energy sector has drawn much attention towards clean and green fuel. In this regard, methanol synthesis is a pivot to the research community as a clean fuel. This book chapter also strives to highlight the methanol synthesis process by performing thermodynamic analysis. A deliberate energy analysis of methanol synthesis by reverse water-gas shift reactor (rWGSR) is performed. The thermochemical processing is utilized to convert methane and carbon dioxide to methanol. On the basis of thermodynamic modelling, concentrations of different constituents over the cycle are determined. It is verified that the optimum state of methanol synthesis is accompanied by the lowest level of CO. Moreover, the concentration of carbon dioxide doesn’t affect the methanol synthesis significantly.

### Methanol—A Sustainable Fuel for SI Engine

Abstract
The vulnerability of crude oil prices with geopolitics around the world is effecting the economy of many countries. The increase in pollution-related deaths due to conventional fossil fuels is making their use debatable every other day. In India, the road transport sector alone utilizes around half of the petroleum consumption. As per reports, the demand for petrol and diesel is increasing at a rate of 6.4% every year. This predicted trend of fuel consumption and growth in motor vehicles are making future energy security fragile. At this juncture, research is being carried out to find suitable alternatives for fossil fuels at least in non-commercial vehicles. Many alternatives such as alcoholic fuels, biodiesels, hydrogen, electric vehicles, and fuel cells are being proposed for their utilization in the present vehicle fleet. Among these alternatives, methanol and its blends stand out in the race. The availability of methanol from a wide variety of feedstock and its characteristics makes it an undeniable alternative for SI engines. Methanol contains ~ 50% inherent oxygen, which leads to cleaner combustion compared to gasoline and diesel. In this chapter, various properties of methanol which makes it a viable SI engine fuel are discussed in detail. The limitations of methanol and its blends in the SI engine are analyzed. The technical solutions available to overcome these limitations are presented in this chapter. The effects of using methanol and its blends on SI engine performance, combustion, and emissions are reviewed in detail. The requirement of catalytic convertors in methanol-fueled engines and design modification required for catalytic convertors for methanol operation are also discussed in the present chapter.

### A Brief Review on Methanol-Fuelled Vehicles (MFV) in China and Implementation Policy

Abstract
By far, China has the largest methanol fuel and vehicle deployment in the world. As a liquid fuel with many properties close to gasoline and diesel, methanol was developed with the aim of enhancing Chinese energy security, reducing fuel costs and lowering emissions of the fast-growing population of vehicles. In parallel, methanol as a fuel served to extend the coal chemistry value chain, boosting local economies within coal-rich provinces of China in the process. Beginning in the 1980s, the R&D efforts on methanol-fuelled vehicles and related methanol fuels from the very early stages were centred in Shanxi Province. This chapter will focus on more recent developments in China—from 2010 to the present. It was during this period that Chinese methanol-fuelled vehicles entered a new stage of development, marked by a national methanol vehicle pilot program, which involved four provinces and the Shanghai city municipality. This pilot program included over 1,000 vehicles, ranging from passenger cars to buses and heavy-duty trucks, with a sharp focus on key concerns from various governmental bodies that would provide policy direction. In March 2019, a promotional policy for methanol-fuelled vehicles was issued by eight leading Chinese ministries and administrations, which paved the way for the future development of methanol-fuelled vehicles in China. Several of the key policy influences as well as the reasoning behind such a development will also be discussed in this chapter.
Kai Zhao, Gregory Dolan, Chris Chatterton

### Regulated and Unregulated Emissions from Methanol Fuelled Engines

Abstract
Globally, the transport sector is under threat due to the rapid depletion of fossil fuel reserves and emissions. Researchers are making constant efforts to reduce the dependence on fossil fuels by trying to find suitable alternative fuels and improving combustion technology. In their earnest efforts, the use of methanol fuel in Internal Combustion Engines (ICEs) appears to be a ray of hope as it can be produced from municipal solid waste (MSW), high ash coal, biomass, and atmospheric CO2, which can definitely reduce the rate of depletion of fossil fuel reserves. Additionally, it results in emissions of less harmful pollutants compared to diesel/gasoline-powered engines due to the presence of the inherent oxygen in its molecular structure. However, it is necessary to study regulated and unregulated tailpipe emissions before starting the commercial use of any alternative fuel on a large scale. The reason is that it can be a substitute for petroleum fuels, but its combustion may be harmful to the environment. This chapter explains the formation of both, regulated and unregulated pollutants from methanol fuelled engines and their adverse effects on human health. Also, it explains the factors that lead to the preference of methanol as a sustainable ICEs fuel. It also summarises various techniques for methanol utilization in both SI and CI engines.
Hardikk Valera, Jakub Čedík, Martin Pexa, Avinash Kumar Agarwal

### Low-Temperature Combustion Kinetics of Methanol-Blended Gasoline and Methanol Synthesized Dimethyl Ether

Abstract
Low-temperature combustion (LTC) is a desirable mode of fuel utilization that ensures low particulate matter (PM) and oxides of nitrogen (NOx) emissions. Low-temperature combustion kinetics of five different methanol-blended gasoline containing 10, 20, 30, 40, and 50% of methanol by volume, respectively, were compared with neat gasoline. Methanol addition in gasoline enhanced low-temperature combustion behavior compared to neat gasoline due to the improved evaporation and mixing characteristics. Unlike the combustion efficiency and power, which showed marginal improvement; carbon monoxide (CO), and NOx emissions dropped significantly with the increase in methanol/gasoline ratio. The effect of methanol/gasoline ratio on different low-temperature chemical pathways was investigated to find an optimum value in terms of combustion performance and emission. Operating strategies to reduce and mitigate unburned methanol emission are discussed, which arose at higher methanol concentrations. Dimethyl ether (DME) is an attractive fuel for compression ignition engines. Since it exhibits low-temperature chemistry, it is particularly suited for homogeneous charge compression ignition (HCCI) Engines. Active radicals generated by low-temperature transient plasma (TP) discharge offer a viable approach to control the combustion phasing of an HCCI engine. In this study, the low-temperature kinetics of DME was explored employing a non-equilibrium plasma ignition strategy using zero-dimensional modeling. A sensitivity analysis of the first and second-stage ignition delays was carried out. The negative temperature coefficient (NTC) regime revealed interesting distinctions between DME and other low molecular weight alkanes. The presence of a thermal bottleneck was found to decrease the efficiency of plasma assistance.
Sayan Biswas, Vyaas Gururajan

### Ignition and Extinction of Hydrogen and Gasoline Blended Methanol Flames

Abstract
Chemical kinetics effects on fundamental laminar combustion processes were investigated for 20% methanol-blended gasoline and 20% hydrogen-blended methanol for a range of equivalence ratios, $$0.5 < \phi < 2$$ using a detailed reaction mechanism comprising of 2027 species and 8619 reactions. Fundamental laminar combustion properties—flame speed, flame thickness, minimum ignition energy, ignition, and extinction strain rates of the two fuel blends were compared with base fuels, methanol, gasoline, and hydrogen. Mean extinction strain rates were nearly twice the ignition strain rates which indicated a hysteresis behaviour of laminar flames. An in-depth analysis of the thermal and chemical flame structure of lean fuel blends was conducted to explore the significance of intermediate products and radical species on flame behaviour. Chemical kinetics caused a greater impact on the ignition process compared to extinction. A sensitivity analysis of ignition and extinction strain rates showed the importance of key reactions and their role in the improvement of laminar flame characteristics of fuel blends. The sensitivity coefficients for ignition were greater compared to extinction signifying a stronger influence of chemical kinetics on the ignition process compared to extinction. The knowledge obtained from this study can be leveraged in creating tailored fuel blends with superior laminar combustion competencies enabling higher efficiency and lesser pollutant emission for automotive applications.
Sayan Biswas

### Measurement, Mechanism and Characteristics of Formaldehyde Emission from Methanol/Gasoline Blends Fueled Engine

Abstract
As a coal-based environmental-friendly fuel, methanol has the great potential to power internal combustion engines. However, as an important intermediate product of methanol combustion, the formaldehyde emission of methanol engines imposes great threats on public health, and more importantly, the targeted method has not been specially developed. This chapter introduces four parts relating to methanol engine-out formaldehyde. (1) the ordinary detection method of airborne formaldehyde and the latest measuring methods of the ones from the engine, (2) the emission mechanism from hydrocarbon and methanol combustion, (3) the emission characteristics from methanol/gasoline blends fuelled engine, and (4) the conversion efficiencies of the three-way catalyst.
Yanju Wei

### Application of Methanol as a Clean and Efficient Alternative Fuel for Passenger Cars

Abstract
Methanol as a low carbon alternative fuel for automobile application has been studied for the past few decades. There are a few technical barriers that have prevented the methanol-fueled vehicle from gaining market penetration. These technical barriers include: cold start difficulty, highly toxic aldehyde emission out of methanol fuel combustion that could be considerably higher than spark ignited (SI) gasoline engines, corrosion, lubricity and material compatibility issues of methanol fuel system components were also concerns for mass production of methanol-fueled vehicles. Tremendous efforts have been made over the past three decades to address these technical challenges. Many investigations have demonstrated brake thermal efficiency advantage of methanol fueled SI engines over conventional gasoline engines for passenger car application, as well as China V emission compliance even after regulated useful lifetime as part of methanol fueled vehicle pilot projects in China. Many studies confirmed that the methanol-fueled engines have excessive aldehyde emissions, especially during the cold start period. But the latest studies also show that using gasoline cold start assistance during engine and after-treatment warm-up period on methanol-fueled engines, along with conventional three-way oxidation catalysts for gasoline engine, is a production viable approach to meet the China V emission standard, including the newly proposed formaldehyde emission limit in China, despite noticeable deteriorations over its useful lifetime. The newly proposed tailpipe methanol emission regulation in China reminds the technical community that additional investigations are needed on methanol-fueled engines as more stringent emission regulations are introduced.
Harold Sun, Wesley Wang, Kim-Pui Koo