Fuel Communications最新文献

Ammonia has long been considered as a candidate vector for power generation, and has specifically gained significant interest recently. Though it is not free of drawbacks, ammonia has been identified as a promising potential alternative fuel for future power generation. Current studies and a growing body of works in this direction drive us closer to a viable solution of ammonia as an important transition into a cleaner future of the energy sector. In this perspective, we explore the use of ammonia as a fuel in combustion applications (with and without additives) and in fuel cells. The objective of this work is to show the prospects and challenges of ammonia as a fuel, and suggest significant topics that could benefit from additional studies.

This paper is a review of renewable energy potentials and energy usage statistics in Ghana. Principally, it covers Ghana's energy consumption from 2000 to 2020. The findings show that Ghana uses both renewable (10%) and non-renewable (90%) forms of energy, but biomass (46.667%) and oil (40.52%) are the commonly used energy resource. This is followed by natural gas (10%), hydroelectric power (7%), and solar energy (0%). The energy consumption by sector from 2000 to 2020 totaled up to 130632ktoe. Residents featured 62,736ktoe (48%) as well as industries, service, agriculture, and transport with each recording 18254ktoe, 5033ktoe, 1957ktoe, and 42652ktoe respectively. The review revealed that the energy demand of the country (Ghana) has shot up and therefore, there is the need for more sustainable energy alternatives to be employed in the energy processes of the country to offset the impacts of future energy crises.

In conventional gas turbine combustors, the combustion chamber linings are perforated and used for cooling. To cool the liner evenly, bias flows are introduced into the combustor at rates that depend on the operating condition. It has been found that airflow through the liner not only provides cooling but also improves sound absorption and acoustic instability. This experiment reports a unique comprehensive investigation of the influences of single and double-layer cylindrical full-scale gas turbine combustor liner sound absorption properties based on the no flow and non zero bias flows. In particular it is shown that combustor liner porosity (determined by orifice diameter and axial pitch distance) has an important influence on non-zero bias flow in that it increases the peak absorption or dissipation compared with that which occurs in the absence of flow. It is shown that the main influence of bias flow is to increase absorption compared with no flow above 600 Hz and to decrease the transmission loss measured in the absence of flow below 600 Hz but to increase it above 600 Hz. Internal resonance in the combustion liner test section influences both absorption and transmission loss spectra near 600 Hz. To create higher damping, and decrease in acoustic instability during the combustion process, gas turbine combustors require mapping between the inner and outer liner perforation to increase efficiency and lower the hydrocarbon emission. The calculated pressure ratio versus mass flow and combined discharge coefficient effect explain the non-linear distribution of the absorptive and dissipative energy measured at the gas turbine combustor.

Of all the types of renewable energy, Renewable Natural Gas (RNG) market has been more supported and developed in Canada due to the lower project cost and the existing NG pipeline infrastructure. RNG is defined as a methane-rich gas obtained through combining Anaerobic Digestion (AD) of underutilized renewable sources (organic waste streams) and upgrading technologies. Membrane separation technology is considered one of Canada's most popular upgrading technologies due to the country-old knowledge regarding gas permeation membranes widely used in the NG industry. Membrane systems are used to recover methane from biogas to a level that meets current natural gas pipeline specifications set out by gas utility companies or meets natural gas vehicle fuel standards set out by engine manufacturers. Here we review standards for gas injection into existing Canadian pipelines, commercial biogas upgrading systems in Canada, and Current biogas upgrading to RNG projects in Canada. We focus more on membrane technology and discuss the possible driving force, module, and configuration alternatives. Finally, this review comprehensively examines membrane types and advances in composite type membranes.

Although recent studies have shown the possibility of running ‘standard’ spark-ignition engines with pure ammonia, the operating range remains limited mainly due to the unfavorable characteristics of ammonia for premixed combustion and often requires the addition of a complementary fuel such as H₂ to extend it. As the best way to add H₂ is to crack ammonia directly on-board, this paper focuses on the impact of the upstream cracking level of ammonia on the performance and emissions of a single cylinder spark ignition engine. Experiments were performed over several equivalence ratios, dissociation rates and load conditions. It is confirmed that only a slight rate of ammonia dissociation (10%) upstream of the combustion considerably enhances the engine's operating range thanks to a better combustion stability. In terms of pollutant emissions, the partial dissociation of ammonia, especially for slightly lean mixtures induces a very clear trade-off between high NO_x and high unburned ammonia level for high and low ammonia dissociation rates, respectively. Therefore, cracking NH₃ does not only improve the operating range of ammonia-fueled spark ignition engines but can also help to reduce NH₃. However, to reach the same engine output work, higher ammonia fuel consumption will be necessary since the global system efficiency is lower using fuel dissociation. In addition, the global warming effect is increased with dissociation level since a higher level of N₂O is generated by the hydrogen contribution.

Fusel alcohol mixtures containing ethanol, isobutanol, isopentanol, and 2-phenylethanol have been shown to be a promising means to maximize renewable fuel yield from various biomass feedstocks and waste streams. We hypothesized that use of these fusel alcohol mixtures as a blending agent with gasoline can significantly lower the greenhouse gas emissions from the light-duty fleet. Since the composition of fusel alcohol mixtures derived from fermentation is dependent on a variety of factors such as biocatalyst selection and feedstock composition, multi-objective optimization was performed to identify optimal fusel alcohol blends in gasoline that simultaneously maximize thermodynamic efficiency gain and energy density. Pareto front analysis combined with fuel property predictions and a Merit Score-based metric led to prediction of optimal fusel alcohol-gasoline blends over a range of blending volumes. The optimal fusel blends were analyzed based on a Net Fuel Economy Improvement Potential metric for volumetric blending in a gasoline base fuel. The results demonstrate that various fusel alcohol blends provide the ability to maximize efficiency improvement while minimizing increases to blending vapor pressure and decreases to energy density compared to an ethanol-only bioblendstock. Fusel blends exhibit predicted Net Fuel Economy Improvement Potential comparable to neat ethanol when blended with gasoline in all scenarios, with increased improvement over ethanol at moderate to high bio-blendstock blending levels. The optimal fusel blend that was identified was a mixture of 90% v/v isobutanol and 10% v/v 2-phenylethanol, blended at 45% v/v with gasoline, yielding a predicted 4.67% increase in Net Fuel Economy Improvement Potential. These findings suggest that incorporation of fusel alcohols as a gasoline bioblendstock can improve both fuel performance and the net fuel yield of the bioethanol industry.

This article presents the actual AFR of the vehicular emission from the tailpipe data of motorcycles with petrol engine in Southwest Nigeria. It also presents the ratio between the actual air-fuel ratio (AFR_actual) and the ideal/stoichiometric air-fuel ratio (AFR_ideal) known as the equivalence air-fuel ratio or lambda (λ). This was compared with the expected value for lambda by the catalytic technology for exhaust gases emission, which is 1 (± 5%). In this study, over 95% of the sampled motorcycles have higher lambda values than expected, thereby emitting very high concentrations of carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO₂). The Portable, Hand-Held, battery-operated Kane automotive 4-gas analyser with detector tube (Model Auto 4-1) was used to measure the automobile emissions. The air-fuel ratio is a significant indicator and very important measure for gasoline engine performance controlling and tuning, and anti vehicles exhaust emissions pollution reasons [1]. Internal combustion (IC) gasoline fuelled engines exhaust gases emission depend heavily and mainly on the air-fuel ratio. For a gasoline fuelled engine, carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) exhaust gases emission are significantly influenced by air-fuel ratio. CO and HC are majorly generated or produced with rich air–fuel mixture, while NOx with lean air-fuel mixtures which mean that there is no fixed air-fuel mixture for which it can obtain the minimum for all exhaust gases emission [2]. This study can help in reducing fuel consumption, improving the quality of fuel combustion and reducing vehicle exhaust emissions in Nigeria.

The efficiency of R600a an eco-friendly refrigerant with graphene nanolubricant was investigated and compared in a domestic refrigerator with R134a refrigerant a zero Ozone Depleting Potential (ODP) but higher Global Warming Potential (GWP) refrigerant. Type K thermocouples were attached to the refrigerator components to track the temperature of the system. Two pressure gauges were also attached to the compressor to determine the pressure at suction and discharge of the domestic refrigerator. A digital wattmeter was used to measure the refrigerator's compressor power consumption. The results showed the evaporator air temperature and pull-down time of R600a with graphene nanolubricant were lower compared to R134a. A higher COP was achieved with R600a in graphene nanaolubricant with an increase in cooling capacity within the range of 5.2% to 14.2% and the power consumption reduced within the range of 8.8% to 26.4%. Hence, R600a/graphene nano lubricant can successfully replace R134a/POE oil in a domestic refrigerator system.