Experimental Investigation on the Emissions of a Port Fuel Injection Spark Ignition Engine Fueled with Methanol–Gasoline Blends

Abstract

The prospect of using methanol as an alternative fuel for vehicles in China is enticing because of its good combustion properties, low production cost, and renewable capacity, but the in-cylinder combustion of methanol also brings extra emissions concerns, such as alcohols and aldehydes. For the impact of methanol–gasoline blends on the pollutant emissions of spark ignition (SI) engines to be investigated, a GEELY MR479Q port fuel injection SI engine was selected for tests of burning different methanol–gasoline blends at wide-open throttle operating conditions, and an AVL Fourier-transform infrared multicomponent gas analyzer was used to measure all of the emissions. Test results show that the methanol-containing fuel blends had positive effects on the engine-out regulated emissions. Nitrogen oxide, carbon monoxide, and nonmethane hydrocarbon emissions were all dramatically reduced when the test engine was fueled with methanol–gasoline blends. Other hydrocarbon emissions such as ethylene, propylene, and soot precursors like acetylene and aromatic hydrocarbons were also reduced with the methanol–gasoline blends. However, the methanol in the fuel blends caused significant elevation of engine-out unburned methanol (CH3OH) and formaldehyde (CH2O) emissions at the same time, especially for high methanol-containing fuel blends, such as M50 and M70. When fueled with M70, engine-out unburned CH3OH emission could reach as high as 500 ppm, and CH2O emission was almost 4 times as much as that of M0. Other emissions like ethanol, acetaldehyde, and 1,3-butadiene were observed to be only slightly influenced by methanol during the engine tests.

A comparative study of the effect of compression ratio on the efficiency and flame development angle in a Cooperative Fuel Research engine fueled with binary gasoline–alcohol blends

“…However, methanol presents certain disadvantages such as toxicity and problems in transportation and storage. 22,23 Zhen and Wang 23 studied methanol and gasoline blends and observed that the increased concentration of methanol implicated a reduction in CO and HC emissions and slightly increased NO x emissions. On the contrary, the emissions of formaldehyde, acetaldehyde and unburned methanol increased when methanol fraction is increased.…”

A comparative analysis of knock severity in a Cooperative Fuel Research engine using binary gasoline–alcohol blends

“…However, the high toxicity of methanol, which leads to special safety measures during handling, transport and refueling, represents an important disadvantage over ethanol. 35,36 Zhen and Wang 36 conducted a review on experimental studies of the combustion of methanol-gasoline blends in SI engines. They observed a predominance of research focused on the emissions generated by the blend.…”

“…However, the high toxicity of methanol, which leads to special safety measures during handling, transport and refueling, represents an important disadvantage over ethanol. 35,36…”

The effects of addition of co-solvents on the physicochemical properties of gasoline–methanol blended fuels

“…The prospect of using methanol as an alternative fuel for vehicles is attractive because of its high-octane number, good combustion properties, and renewable capacity, even if the in-cylinder combustion brings concerns because, compared to gasoline, it has lower energy content and higher RVP. 13–15 Methanol’s blending octane values are nominally 129–134 RON and 97–104 MON. Methanol’s actual octane numbers will vary depending on the octane of the gasoline base fuel and its composition.…”