Ethanol Gasoline Research Articles

Influence of injection pressure on performance and emission characteristics of single cylinder RCCI engine fuelled with ethanol gasoline and diesel biodiesel blends

Reactivity controlled compression ignition (RCCI) has great potential for a simultaneous reduction in Nitrogen oxides (NOx) and particulate matter (PM) with increase in thermal efficiency. In this experimentation, an attempt is made to investigate the effect of injection pressure on the performance emission and combustion characteristics of single cylinder RCCI engine. Literature reveals that injection pressure has a great influence on the quality of charge preparation, fuel stratification, and incylinder reactivity. Suitably modified engine was operated for 0 to 12 kg loads, for 400 to 700 injection pressure. The blend of ethanol gasoline E20 used as a low reactivity fuel and blend of diesel jatropha biodiesel B20 used as a high reactivity fuel. Experimental results showed that increase in injection pressure enhances the degree of charge homogeneity, reduces the combustion duration, and provides higher rate of energy release. For 12 kg load and 700 bar injection pressure, it is observed that 5% rise in thermal efficiency, 27% reduction in smoke opacity, 2% reduction in HC, 4% reduction in CO and 20% rise in NOx as compared to 400 bar injection pressure.

Implementation of Oxy-Fuel Combustion (OFC) Technology in a Gasoline Direct Injection (GDI) Engine Fueled with Gasoline-Ethanol Blends.

Nowadays, to mitigate the global warming problem, the requirement of carbon neutrality has become more urgent. Oxy-fuel combustion (OFC) has been proposed as a promising way of carbon capture and storage (CCS) to eliminate carbon dioxide (CO2) emissions. This article explores the implementation of OFC technology in a practical gasoline direct injection (GDI) engine fueled with gasoline–ethanol blends, including E0 (gasoline), E25 (25% ethanol, 75% is gasoline in mass fraction), and E50 (50% ethanol, 50% is gasoline in mass fraction). The results show that with a fixed spark timing, φCA50 (where 50% fuel is burned), of E50 and E25 is about 4.5 and 1.9° later than that of E0, respectively. Ignition delay (θF) and combustion duration (θC) can be extended with the increase of the ethanol fraction in the blended fuel. With the increase of the oxygen mass fraction (OMF) from 23.3 to 29%, equivalent brake-specific fuel consumption (BSFCE) has a benefit of 2.12, 1.65, and 1.51% for E0, E25, and E50, respectively. The corresponding increase in brake-specific oxygen consumption (BSOC) is 21.83, 22.42, and 22.58%, respectively. Meanwhile, θF, θC, and the heat release rate (HRR) are not strongly affected by the OMF. With the increase of the OMF, the increment of θF is 0.7, 1.8, and 2.2° for E0, E25, and E50, respectively. θC is only extended by 1, 1.1, and 1.4°, respectively. Besides, by increasing the intake temperature (TI) from 298 to 358 K under all of the fuel conditions, BSFCE and BSOC present slight growth trends; θF and θC are slightly reduced; in the meantime, φCA50, φPmax (crank angle of peak cylinder pressure), and the position of the HRR peak are advanced by nearly 1°.

Impact of coolant temperature on the combustion characteristics and emissions of a stratified-charge direct-injection spark-ignition engine fueled with E30

The direct injection spark ignition (DISI) engine has received considerable attention due to its potential to increase the power density of traditional spark ignition engines while significantly improving fuel economy through lean, unthrottled combustion. However, the market introduction of DISI engines operated in a lean combustion mode is inhibited by their unsatisfactory emissions, especially during cold start conditions that make proper mixture formation more challenging. Ethanol-blended gasoline, now a widely used fuel, makes the cold start of a DISI engine more difficult, leading to higher HC and soot emissions because of the high latent heat of vaporization of ethanol relative to gasoline. This work investigated the impact of coolant temperature on the characteristics of combustion and emissions in a stratified-charge DISI engine fueled with an E30 fuel (i.e. 30% ethanol in gasoline), while the coolant temperature was alternated between four levels (45, 60, 75, and 90 °C) to simulate different conditions throughout the warm-up process. The experiments showed that the coolant temperature affected the post-spark inflammation time, as well as the speed, intensity, and stability of the combustion process in the engine. When the coolant temperature rose, the engine produced more NOX and less CO, PM and HC. In addition, high-speed direct photography was used to obtain crank-angle resolved images of fuel sprays and flames in the cylinder. As the coolant temperature rose, the liquid spray lengths became shorter, reducing the possibility of wall wetting, and reduced irradiance from soot particles also indicated less non-premixed combustion. The in-cylinder imaging results are consistent with the observed combustion and emission characteristics and shed light on the underlying processes. Some potential solutions to the emissions challenges faced here could be either raising in-cylinder temperatures by using trapped residuals or modifying the injection schedule, for example by increasing the number of injections or to inject later in the cycle into a higher-density environment.

Antenna Sensor Based on AMC Array for Contactless Detection of Water and Ethanol in Oil

When ethanol and water are mixed into gasoline, the dielectric properties of gasoline will change. Based on this characteristic, we propose an antenna sensor and study its radiation and sensing performance in detection of ethanol gasoline in 6-7GHz band. In order to avoid the corrosion of the oil sample on the antenna, the antenna adopts a multilayer dielectric substrate structure. A <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\times 2$ </tex-math></inline-formula> artificial magnetic conductor (AMC) array is loaded on the bottom of the antenna to increase the gain of the sensor and reduce the return loss. The antenna sensor has good radiation pattern with a peak gain of 4 dB and high quality factor(Q) up to 69. Furthermore, the antenna sensor shows the advantages of high sensitivity and wide detection range on the detection of oil-water mixture and ethanol gasoline concentration. In order to verify the simulated results, the radiation and sensing performance of the antenna were measured, and the measured results were basically consistent with the simulated ones. Therefore, the proposed antenna sensor can be used for real-time wireless detection in ethanol gasoline transportation.

Study on combustion and emissions of a hydrous ethanol/gasoline dual fuel engine with combined injection

Hydrous ethanol has lower cost and energy consumption during the production process than anhydrous ethanol. Many researchers used hydrous ethanol instead of anhydrous ethanol to manufacture hydrous ethanol-gasoline. The water ratio in hydrous ethanol (ω) determines the energy consumption in the production process of ethanol. However, no one researched the effects of different ω on combustion and emissions of hydrous ethanol-gasoline. So, we prepared five kinds of ethanol with different ω (0, 5%, 10%, 15%, 20% vol.) to research the effects of ω on combustion and emissions. This study adopted combined injection with hydrous ethanol direct injection plus gasoline port injection (HEDI + GPI). The engine speed was 1500 rpm, and λ was 1, the intake manifold absolute pressure was 48 kPa, the direct injection ratio was 20%, five spark timings varied from 5 °CA BTDC to 25 °CA BTDC. The results showed hydrous ethanol prolonged flame development and propagation duration, decreased Tmax and Pmax, delayed APmax. Water increased COVimep, but using hydrous ethanol at the reasonable spark timing would not significantly affect the stability. Meanwhile, when the spark timing was MBT, compared with GE (gasoline/anhydrous ethanol dual fuel) fuel, as ω in GEW (gasoline/hydrous ethanol dual fuel) fuels increased, torque and brake thermal efficiency improved by 1.69%, 1.13%, −0.01%, −0.77%; HC increased by 2.13%, 9.02%, 23.89%, 37.15%; CO decreased by 41.95%, 28.56%, 5.59%, 2.46%; NOx decreased by 10.10%, −0.75%, −0.17%, 4.18%; total PN emissions decreased by 24.07%, 69.57%, 36.34%, 32.45%. Meanwhile, more water caused the size of particles to drop, made particles smaller.

Effects of Water Ratio in Hydrous Ethanol on the Combustion and Emissions of a Hydrous Ethanol/Gasoline Combined Injection Engine under Different Excess Air Ratios.

Ethanol is usually combined with gasoline to manufacture ethanol–gasoline with excellent combustion characteristics. However, extracting water from hydrous ethanol to manufacture anhydrous ethanol consumed much energy, which increases the production cost of ethanol–gasoline. Many researchers have studied the combustion and emissions of hydrous ethanol–gasoline to explore the application of hydrous ethanol–gasoline as the fuel for spark-ignition engines. Most previous studies changed the hydrous ethanol ratio with fixed purity in hydrous ethanol–gasoline to study the effects of hydrous ethanol. Different from previous studies, this paper studied the effects of water ratio (Wr) in hydrous ethanol on the combustion and emissions of a hydrous ethanol/gasoline combined injection engine under different excess air ratio (λ) values. The ratios of ethanol and gasoline keep constant, while the purity of hydrous ethanol changes during the research. The experiment adopted the combined injection mode with hydrous ethanol direct injection plus gasoline port injection; the direct injection ratio was 20%. The experiment set three λ (0.9, 1, and 1.2) and five Wrs (0, 5, 10, 15, and 20%). The test engine’s speed was 1500 rpm, and the intake manifold absolute pressure was 48 kPa. Results showed that water inhibited combustion, prolonged CA 0-10 and CA 10-90, reduced Pmax and Tmax, and delayed APmax; larger λ made the deterioration on combustion more obvious, and the smaller λ had a larger tolerance to water. Water could increase torque and improve emissions, but different parameters corresponded to different optimal Wrs. For torque, the optimal Wr was 5%. For HC emissions, the optimal Wr was 0%; for CO emissions, the optimal value was 5%; and for NOx emissions, the best value was 20%. The best Wr was 10% for particle number (PN) emissions. Under the optimal Wr condition, when λ values were 0.9, 1, and 1.2, compared with pure gasoline, the torque increased by 7.5, 5.54, and 5.31%; HC emissions decreased by 21.37, 23.43, and 26.58%; NOx emissions decreased by 4.26, 11.47, and 12.55%; CO emissions decreased by 17.51, 34.56, −50%; and the total PN emissions decreased by 87.64, 89.64, and 76.07%.

A comparison of the emissions of gasoline–ethanol fuel and compressed natural gas fuel used in vehicles with spark ignition engine in Rio de Janeiro: Brazil

A comparison of the emissions of gasoline–ethanol fuel and compressed natural gas fuel used in vehicles with spark ignition engine in Rio de Janeiro: Brazil

Volatility and physicochemical properties of gasoline-ethanol blends with gasoline RON-based 88, 90, and 92

A binary set of gasoline-ethanol (GE) blends from three types of gasoline’s research octane number (RON), i.e., RON 88, RON 90, and RON 92, were formulated. Herein, the volatility characteristics, i.e., vapor pressure and distillation behavior were measured. Also, physiochemical properties, i.e., density and RON for each blend and oxygenating compounds influence from ethanol, were discussed. The obtained result revealed that the vapor pressure of GE blends is highly affected by non-ideal vapor-liquid equilibrium mixture. The initial boiling point of GE blends would gradually increase as the higher ethanol’s concentration. However, the final boiling point of the GE blends never exceeds the final boiling point of the pristine gasoline, yet never less than the final boiling point of pristine ethanol. Furthermore, RON, oxygenate content, and density, showed a linear increment curve by increasing ethanol content on each gasoline type. Finally, the results showed that it might be advantageous to use ethanol to provide the added value of gasoline RON 88, RON 90, or RON 92 to form a new gasoline product by considering a confident RON and the limitations for high and low volatility.

Analysis of Hydrous Ethanol Price Competitiveness after the Implementation of the Fossil Fuel Import Price Parity Policy in Brazil

Competition is a relevant element in any open economy. Public policies are necessary to induce economic efficiency and to create conditions to preserve or stimulate a competitive environment. This paper aims to assess the competitiveness of hydrous ethanol price in a period of political, social and economic crises, in 15 Brazilian state capitals between the years 2012 and 2019. We compared the ethanol–gasoline price ratio behavior in two different periods, before and after the import parity price policy implemented by Petrobras in 2016. Mann–Whitney and Levene’s tests, two non-parametric statistical methods, were applied to verify significant changes between these periods. The implementation of changes in Petrobras’ pricing policy from 2016 onwards caused a statistically significant increase in the ratio coefficient of variation in two-thirds of the distribution market and more than the half of analyzed retail markets. Second, overall, the cities that showed statistically significant changes in the median and coefficient of variation in the distribution market price ratio were followed by the retail market. Our findings suggest that government interventions in the fuel and byproduct final selling prices to distributors negatively impact competition between companies that are part of the fuel distribution and retail chain, also affecting the sale of biofuels in Brazil and discouraging the initiatives to use renewable fuels to reduce the emission of pollutants.

Kinetic Modeling Study of Laminar Burning Velocity of Gasoline–Ethanol–Methanol Blends at Elevated Temperature and Pressure

Kinetic Modeling Study of Laminar Burning Velocity of Gasoline–Ethanol–Methanol Blends at Elevated Temperature and Pressure

Effect of operation under lean conditions on NOx emissions and fuel consumption fueling an SI engine with hydrous ethanol–gasoline blends enhanced with synthesis gas

For the purpose of creating a clean environment, achieving higher engine efficiency, and complying with increasingly strict emission regulations, many methods have been developed to enhance SI engines performance and decrease their pollutant emissions. In this study, the effects of using hydrous ethanol–gasoline blends and synthesis gas addition on NOx emissions and fuel consumption under lean and ultra-lean conditions (i.e. at air/fuel equivalence ratios (λ) = 1.13, 1.26 and 1.46) were investigated using a Spark-Ignition (SI) engine. The engine was fuelled with a Saudi Arabian gasoline grade (RON91), mixed with 5 % and 10 % of hydrous ethanol containing different water concentrations (5 %, 10 %, 30 %, and 40 %). An on-board plasma fuel reformer was employed for the production of hydrogen-rich syngas via the partial oxidation of gasoline. The results revealed the evident positive effect of operating under lean conditions using hydrous ethanol–gasoline blends on reducing the NOx emissions. In addition, NOx emissions decreased with increasing the air/fuel ratio to reach the minimum at the highest lean condition. However, fuel consumption increased with equivalence air/fuel ratio from low-lean at λ = 1.13 to high lean at λ = 1.46 conditions. Syngas addition to the fuel blend under lean conditions resulted in further reduction of NOx emissions but increased the overall fuel consumption. The results showed that up to 4 % of water enrichment of hydrous-gasoline blend can effectively enhance the engine thermal efficiency and reduce NOx emission.

Fuel Consumption and Emissions Analysis of a Light Vehicle Fuelled with Two Ethanol–Gasoline Blends in Urban Driving Conditions of Lima Metropolitana

We present a comparative study of fuel consumption, emissions factors, and vehicle-specific power of a light vehicle operating with two gasoline–ethanol blends as fuel: commercial gasohol (E7.8) and an alternative mix with 10% v/v of ethanol (E10). For this purpose, a vehicle in the city’s fleet was equipped with a central system of data acquisition, whose main function was to capture second-by-second data of the air intake of the engine, the emissions concentration levels in the exhaust, the distance traveled, vehicle speed, and environmental conditions during testing. The measuring campaign was carried out in the city of Lima Metropolitana. Fuel consumption was calculated indirectly, using air intake measurements. The vehicle’s engine emissions were analysed using the mass flow rates of CO2, CO, HC, and NOx, as well as the vehicle-specific power. The results show that, in traffic conditions, the change in fuels does not affect the consumption. On the other hand, a correlation was found between the vehicle-specific power and the emissions mass flow. During the comparison between fuels, the results showed an increase in the mass flow standard deviation when using E10.

Characterization of vibration and noise pollution of SI engine fueled with magnetized ethanol–gasoline blends by time–frequency methods

The purpose of the present study was to investigate the effects of magnetized ethanol–gasoline fuel blends on the vibration and sound status of a single-cylinder gasoline engine. Totally 36 tests were conducted including two factors: ethanol (blended by gasoline with share of 0, 5, 10, and 20%) and magnetic field intensity (0, 5300, and 7000 G) at three replications as a factorial experiment based on completely randomized design. The sound signals of the engine at 10 cm distance from the driver’s ear were recorded and its engine vibration was measured in Z direction. The results of statistical analysis of vibration and sound data showed significant effects of both factors on the vibration and sound signals. The maximum sound pressure level with averages of 88.41 belonged to pure gasoline and magnetic intensity of 7000 G and minimum value (78.94 dB) belonged to 10% ethanol in the blended fuel and magnetic intensity of 5300 G. The driver can operate the engine for 10–20% ethanol shares with all studied magnetic intensities without use of any ear protector. In the presence of magnetic field, vibration decreased by increasing ethanol up to 10%. The maximum amount of vibration in frequency domain obtained without using magnetic field. For 5300 G magnetic intensity, the least amount of vibration was observed for all frequencies.

Electrochemical Corrosion Tests in Low-Conductivity Ethanol-Gasoline Blends: Application of Supporting Electrolyte for Contaminated E5 and E10 Fuels.

Ethanol-based E5 and E10 fuels have extensively been used as automotive fuels in gasoline engines. However, especially when contaminated, these fuels can exhibit corrosion effects on some engine construction parts such as mild steel. Thus, the study of mild steel corrosion resistance has become of the utmost importance. Electrochemical methods such as electrochemical impedance spectroscopy (EIS) and polarization characteristics measurements (Tafel scan—TS) were proven to be very valuable in studying the mild steel corrosion behavior in ethanol–gasoline blends (EGBs). However, the use of these methods was, so far, very limited for low-ethanol-content EGBs such as E5 and E10 due to their low conductivity. In this study, we present modified EIS and TS corrosion measurements based on the use of tetrabutylammonium tetrafluoroborate (TBATFB) at 500 mg/L as a supporting electrolyte. This modification led to an increase in the contaminated E5 and E10 fuels’ conductivity, which allowed us to successfully perform the electrochemical corrosion tests. The corrosion current densities were determined to be 1.5 × 10–3 and 1.5 × 10–2 μA/cm2 for the tested E5 and E10 fuels, respectively. These modified methods present a significant extension of an electrochemical testing apparatus for steel corrosion studies in EGBs. They can allow one to obtain instantaneous information about the occurring corrosion process and, thus, estimate the materials’ lifetime in corrosive environments and potentially help to prevent corrosion.

Using an oxidation flow reactor to understand the effects of gasoline aromatics and ethanol levels on secondary aerosol formation

Fuel type and composition affect tailpipe emissions and secondary aerosol production from mobile sources. This study assessed the influence of gasoline fuels with varying levels of aromatics and ethanol on the primary emissions and secondary aerosol formation from a flexible fuel vehicle equipped with a port fuel injection engine. The vehicle was exercised over the LA92 and US06 driving cycles using a chassis dynamometer. Secondary aerosol formation potential was measured using a fast oxidation flow reactor. Results showed that the high aromatics fuels led to higher gaseous regulated emissions, as well as particulate matter (PM), black carbon, and total and solid particle number. The high ethanol content fuel (E78) resulted in reductions for the gaseous regulated pollutants and particulate emissions, with some exceptions where elevated emissions were seen for this fuel compared to both E10 fuels, depending on the driving cycle. Secondary aerosol formation potential was dominated by the cold-start phase and increased for the high aromatics fuel. Secondary aerosol formation was seen in lower levels for E78 due to the lower formation of precursor emissions using this fuel. In addition, operating driving conditions and aftertreatment efficiency played a major role on secondary organic and inorganic aerosol formation, indicating that fuel properties, driving conditions, and exhaust aftertreatment should be considered when evaluating the emissions of secondary aerosol precursors from mobile sources.

Volatile organic compounds from a mixed fleet with numerous E10-fuelled vehicles in a tunnel study in China: Emission characteristics, ozone formation and secondary organic aerosol formation

The Chinese government has developed an ambitious project to promote the application of ethanol gasoline (E10) on a national scale since 2017. Given the difference in fuel properties between E10 and traditional gasoline, it is necessary to evaluate the volatile organic compound (VOC) emissions from E10-fuelled vehicles. In this study, a two-week sampling campaign was conducted in an urban tunnel, in which E10-fuelled vehicles were dominant, to evaluate the characteristics of VOC emissions from the mixed fleet. In total, 105 VOC species were identified, and the ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) were estimated. The results showed that for vehicular VOC concentrations in the tunnel, alkanes, oxygenated VOCs (OVOCs) and alkenes were the most abundant VOC groups, with the average proportion being more than 80% of the total VOCs. The fleet-average VOC emission factor (EF) was 14.8 mg/km/veh, which was much lower than that from traditional gasoline-fuelled vehicle fleets, and alkanes, OVOCs, alkenes and aromatics were the major VOC groups. Because of the large number of E10-fuelled vehicles in the mixed fleet, a high proportion of OVOCs among the vehicular VOC emissions was observed. Ethane, acrolein, ethanol, ethylene and toluene were the top five VOC species with the largest EF in VOC emissions from the fleet. Alkenes were the main contributors with an average contribution of 43.9% of the total OFP, whereas aromatics dominated the total SOAFP by 95.8% on average. These results may provide a reference for the extensive application of ethanol gasoline and the development of vehicular emission models.

A reduced mechanism for the combustion of gasoline-ethanol blend on advanced engine combustion modes

A reduced mechanism composed of 144 species and 653 reactions is developed in the present study for simulating the combustion and soot emission of gasoline-ethanol blends on advanced engine combustion modes. The sub mechanism for gasoline combustion is reduced from a detailed mechanism based on the surrogate mixture of n-heptane, iso-octane, toluene, and 1-hexene. A composite approach composed of the path flux analysis and sensitivity analysis is used to perform the reduction. The reduced gasoline mechanism is comprehensively validated against the original detailed mechanism by predicting ignition day, instantaneous temperature, and species mole fraction during the homogeneous auto-ignition and the temperature profiles of perfectly stirred reactor, especially under low-temperature combustion conditions. A reduced ethanol mechanism is also obtained using the same reduction approach and then combined with the reduced gasoline mechanism. By further implementing elementary reactions related to the formation of polycyclic aromatic hydrocarbons (PAHs), the resulting combined mechanism can be used to simulate the ignition, combustion, and PAHs formation of gasoline-ethanol blends with different ratios. The fidelity of the present combined mechanism is comprehensively examined by predicting ignition delay, laminar burning velocity, and PAHs formation of various blends of gasoline surrogates and ethanol. Good agreement is obtained between the predicted properties and the corresponding experimental data.

Fuel Economy and Emissions of E85 in Passenger Cars - A Move towards Flex Fuel Vehicle

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Many countries are developing strategies to curb the consumption of fossil fuels, and to increase the share of alternative fuels such as alcohols, natural gas, fuel cell and electricity in the energy pool in order to improve energy security and reduce atmospheric pollution. Alcohol fuels are promising one and it has been widely used in many countries as blending component for gasoline. Ethanol has a high-octane number but it has a lower calorific value than gasoline. The performance of engine may be affected with higher percentage of ethanol in gasoline due to demand for larger quantity of fuel that could not be supplied by vehicles which are tuned to run on gasoline only. In this study, a second electronic control unit (ECU) was installed in series with the existing commercial or primary ECU and an ethanol sensor was installed in the fuel line. This secondary ECU modulates the fuel injection pulse width of the primary ECU depending on ethanol concentration in the fuel. The vehicle studies were carried out using Indian automotive gasoline meeting IS:2796 specification and 85% ethanol blended gasoline (E85) in a climatically controlled chassis dynamometer lab in which test cell temperature maintained at 25±1 °C throughout the test. Modified Indian Driving Cycle tests (MIDC) and constant speed tests were carried out using E85 and commercial gasoline to investigate the fuel economy, gaseous mass emissions, particulate emission in terms number and size characteristics. Gaseous emission was reduced up to 30% with the penalty of reduction in fuel economy by approximately 30% over the MIDC. The vehicle power was maintained while using both fuels at respective constant speeds during the road load simulation cycles however an increase in fuel consumption was observed with E85. The tailpipe exhaust particle emission measurement had shown up to 50% reduction in exhaust particulate emissions with E85. This study demonstrates the potential of using higher blends of ethanol up to E85 and meeting power or speed demand at constant speeds and driving cycle tests.&lt;/div&gt;&lt;/div&gt;

What’s the Role Of Corn Ethanol Fuel in China: From the Life Cycle Cost View

China originally planned to use fuel ethanol gasoline nationwide in 2020, and taking corn as an important raw material of ethanol gasoline, this paper analyzed the life cycle cost model of corn fuel ethanol gasoline and traditional gasoline from production to consumption, including internal and external cost calculations. The internal cost is the actual cost of the industry chain, while the external cost is converted into the cost value by examining the environmental impact of pollutant emission levels in each stage of the life cycle of ethanol gasoline production. Based on this model, by selecting the project data of specific regions and manufacturers in China, it can be calculated as follows: The main links affecting the internal cost of ethanol gasoline production are crude oil procurement cost, refinery and ethanol plant construction cost; The main influencing link of external cost is the emission of ethanol gasoline combustion, including the fuel, power and other energy consumption factors in the production of ethanol and gasoline; The cost can be optimized from the perspective of production technology, technological process, energy material consumption and various labor costs. Assuming E10 is used in the whole Chinese market, the empirical results are as follows: among the pollutants produced by the use of ethanol-added gasoline in the whole region, CO2 emission reduction is the largest, exceeding 53 million tons, followed by CO and wastewater emission reduction of 1.78 million tons and 1.58 million tons respectively. In terms of the conventional gasoline, the CO emission reduction of about 20% is the largest, followed by about 17% reduction of HC, about 15% reduction of SO2 and about 9% reduction of CO2 respectively. These results show that the promotion of ethanol gasoline (E10) usage in China has a considerable reduction effect of emission if the availability of raw materials are sufficient. The life cycle external cost of ethanol gasoline is 11.45%, lower than that of conventional gasoline. In 2019, China’s fuel ethanol production capacity was 4.15 million tons, and the actual production was about 3 million tons. Assuming that all of it were used to produce E10 ethanol gasoline, compared with traditional gasoline consumption, the emission reduction benefit of E10 gasoline would be nearly $84.7 million.

Improvement of combustion and emission by combined combustion of ethanol premix and gasoline direct injection in SI engine

In this paper, a test platform for ethanol port injection plus gasoline direct injection was built to explore the effects of different ethanol-gasoline ratios (Re), direct injection timing (DIT) and ignition timing (IT) on the combustion and emissions of a SI engine. Results clearly show that when the total fuel contains more ethanol, the ignition timing corresponding to the maximum torque is smaller than the ignition timing when the total fuel contains more gasoline. Compared with the sole ethanol port injection (EPI) mode and gasoline direct injection (GDI) mode, G25 with EPI + GDI is the best mode for high-efficiency combustion and G25 with IT = 20°CA BTDC and DIT = 120°CA BTDC can be regarded as the optimal operating condition for highest torque output, braking thermal efficiency and lowest BSFC. As for exhaust emissions, CO and HC reach the lowest at G25 while NOx has an opposite trend. Delayed ignition within the range of 10-30°CA BTDC reduces HC and NOx emissions. As for particle number emissions, the size of peak particle number gradually decreases from G100 to G0, the accumulation particle number (APN) is further oxidized and shows a significant downward trend with the increase of ethanol. The lowest TPN was obtained at G25 in which the TPN has dropped by 9% and 85% respectively compared with sole EPI and GDI mode. When Re ≥ 50%, the nucleation mode particle number (NPN) in the total particle distribution is higher than the accumulation mode particle number, while there is an opposite result when Re＜50%. Overall, the findings of this paper make contributions to the development of high-efficiency and low-pollution combined engines and further promote the application of clean alternative fuels.