Mixed Fuels Research Articles

Experimental investigation on noise and vibrations of biodiesel-butanol blends for diesel engine

Diesel engines have extensively used several developing countries to produce electricity. This is done in various sizes, small and medium, which are driven by millions of diesel engine generators. These engines or generators produce vibrations and noisy and pollute the air. Thus, an alternative to diesel is needed for such applications. Turpentine-diesel fuel mixture is one such alternative. However, there have not many efforts made so far to evaluate noise and vibration characteristics. This study is done to try filling the gap and comprehensively investigate the use of Turpentine-diesel mixed fuels. This experiment uses a single-cylinder-4- stroke diesel engine operated at different rpm speeds and engine loads. Detailed measurements are made for engine noise and vibration. This measurement is used to connect the reciprocity of engine noise and vibration. The relationship of chemical parameters and physical properties to the tested fuel explored. The test results using turpentine-diesel fuel show the vibration and noise characteristics better for the upper-middle load. The correlation between noise and vibration characteristics of the test fuel has a strong relationship. This study has provided a detailed phenomenological explanation of the nature of the fuel. Finally, turpentine blends are a viable alternative to diesel fuel, especially in diesel engines

Potential and limiting factors in the use of alternative fuels in the European maritime sector.

The maritime sector is a key asset for the world economy, but its environmental impact represents a major concern. The sector is primarily supplied with Heavy Fuel Oil, which results in high pollutant emissions. The sector has set targets for deacrbonisation, and alternative fuels have been identified as a short-to medium-term option. The paper addresses the complexity related to the activities of the maritime industry, and discusses the possible contribution of alternative fuels. A sector segmentation is proposed to define the consumption of each sub-segment, so to compare it with the current alternative fuel availability at European level. The paper shows that costs and GHG savings are fundamental enablers for the uptake of alternative fuels, but other aspects are also crucial: technical maturity, safety regulation, expertise needed, etc. The demand for alternative fuels has to be supported by an existing, reliable infrastructure, and this is not yet the case for many solutions (i.e. electricity, hydrogen or methanol). Various options are already available for maritime sector, but the future mix of fuels used will depend on technology improvements, availability, costs and the real potential for GHG emissions reduction.

Structural, optical and photocatalytic properties of cuboid ZnO particles

Zinc oxide (ZnO) powders were prepared by solution combustion method using trimethyloctylammonium bromide (OTAB) and a mixture of OTAB and citric acid as fuel. Single phase ZnO powders with wurtzite structure were directly formed at high fuel contents (φ ≥ 1). The porous microstructure of combusted ZnO powders by mixed fuels had the specific surface area in the range of 73–416 m2/g in which increased with the increase of amount of fuels. The ZnO powders synthesized by single OTAB fuel were composed of the compacted agglomeration particles with cuboid-like morphology. The optical and photocatalytic properties of ZnO powders were determined as a function of fuel type and contents by diffuse reflectance spectroscopy and photoluminescence spectroscopy techniques. The ZnO powders obtained by OTAB-citric acid mixed fuel at φ = 1.5 showed the highest adsorption (53%) and photodegradation (95%) efficiency of MB dyes during 90 min under ultraviolet (UV) light irradiation.

Gridded fossil CO2 emissions and related O2 combustion consistent with national inventories 1959\u20132018

Quantification of CO2 fluxes at the Earth’s surface is required to evaluate the causes and drivers of observed increases in atmospheric CO2 concentrations. Atmospheric inversion models disaggregate observed variations in atmospheric CO2 concentration to variability in CO2 emissions and sinks. They require prior constraints fossil CO2 emissions. Here we describe GCP-GridFED (version 2019.1), a gridded fossil emissions dataset that is consistent with the national CO2 emissions reported by the Global Carbon Project (GCP). GCP-GridFEDv2019.1 provides monthly fossil CO2 emissions estimates for the period 1959–2018 at a spatial resolution of 0.1°. Estimates are provided separately for oil, coal and natural gas, for mixed international bunker fuels, and for the calcination of limestone during cement production. GCP-GridFED also includes gridded estimates of O2 uptake based on oxidative ratios for oil, coal and natural gas. It will be updated annually and made available for atmospheric inversions contributing to GCP global carbon budget assessments, thus aligning the prior constraints on top-down fossil CO2 emissions with the bottom-up estimates compiled by the GCP.

Investigation of the process of intake and gas exchange of a diesel engine when operating on mixed fuel

The subject of the research is to determine the parameters of the diesel intake and gas exchange pro-cess when using a mixed fuel (MF), consisting of diesel fuel (DF) and rapeseed oil (RO). The main goal of this work is to determine the dependences of the parameters of the intake and gas exchange of a diesel engine on the composition used by the MF. To achieve this goal, theoretical and experimental studies of the D-245,5S tractor diesel engine with a characteristic of 4ChN 11,0/12,5 were carried out on the following MF compositions: DF 80 % + RO 20 %, DF 45 % + RO 55 %, DF 20 % + RO 80 %, as well as pure diesel fuel. During the carried out studies there were obtained the dependences of the hourly air flow rate, the cylinder filling factor and the charge density in the intake manifold of a diesel engine when operating on DF and MF on the crankshaft rotation speed and load at = 1800 min1 and = 1400 min1. It is theoretically determined and experimentally confirmed that the composition of the used MF has practically no effect on the characteristics Gв, v and к depending on pe of the diesel engine. As a result, it was found that with an increase of n from 1400 to 1800 min1 on all compositions of MF the Gв increased from 276 to 394 kg/h, from 1,44 to 1,70 kg/m3, and at increase of n from 1800 to 2000 min1, the Gв decreased from 394 to 322 kg/h, from 1,70 to 1,49 kg/m3 and from 0,97 to 0,77. With an increase pe from 0,2 to 1,2 MPa on all compositions the MF increased, at n = 1400 min1, from 187 to 276 kg/h, к from 1,29 to 1,44 kg/m3 and v from 0,73 to 0,97, at n = 1800 min1, Gв from 274 to 394 kg/h, к from 1,29 to 1,69 kg/m3 и v from 0,83 to 0,91, respectively.

Determination of the optimal composition of mixed fuel based on the environmental performance of a diesel engine

The use of rapeseed oil (RO) in tractor engines and other agricultural machinery in its pure form or a mixture of RO with diesel fuel (DF) imposes a number of limitations associated with some difference in physical and chemical properties. Therefore, the most promising is the use of mixed fuel (MF) consisting of DF and RO. The purpose of these studies is to determine the optimal composition of the MF, consisting of DF and RM by optimizing the approximated dependences of the environmental indicators of a diesel engine. To solve this problem, bench tests of the operation of the D-245.5S diesel engine (4ChN 11,0/12,5) were carried out. The following determined environmental performance indicators of a diesel engine are selected: soot (С), nitrogen oxides (NOx), unburned hydrocarbons (CxHy), carbon dioxide (CO2) and carbon monoxide (CO). The studies were carried out on various compositions of MF, consisting of 80 % DF and 20 % RO, 55 % DF and 45 % RO, 20 % DF and 80 % RO by weight, respectively. As a result of the bench tests, two load characteristics were obtained, the one at a speed of n = 1400 min1 corresponding to the value of the maximum torque, and the second at a speed of n = 1800 min1 corresponding to the value of the rated power, as well as the external speed characteristic of the D-245.5S tractor diesel engine (4ChN 11,0/12,5). The analysis of the obtained experimental data revealed the dependence of environmental indicators on the rotational speed of the diesel engine crankshaft, the average effective pressure and the addition of RO in MF by weight. Using the least squares method, the approximated mathematical dependences of the ecological indicators of a diesel engine are determined. The analysis of the obtained dependencies showed that: the increase in the crankshaft speed n, the proportion of RO in MF and a decrease in the average effective pressure pe, leads to a decrease in soot С to 4,0 %, nitrogen oxides NOx to 100,0 ppm, unburned hydrocarbons CxHy to 1,0 ppm, carbon dioxide CO2 up to 2 % and an increase in carbon monoxide CO up to 0,16 %. As a result of solving the obtained system of equations for the approximated dependences of environmental indicators, the optimal addition of RO to MF of up to 35 % by weight was determined.

The Role of Retrospective Analysis in an Era of Deregulation: Lessons from the US Mercury and Air Toxics Standards

As of late 2020, the Trump administration had initiated almost 100 rollbacks of US environmental regulations. A careful assessment of the benefits and costs of rolling back an existing regulation can and should inform such decisions. When assessing the potential rollback of an existing regulation, analysts can often learn from the regulation’s implementation through retrospective analysis as well as from advances in scientific knowledge. We discuss recent actions concerning the Mercury and Air Toxics Standards (MATS) to illustrate the potential lessons from doing so. In the case of MATS, advances in science have shed light on broader exposure pathways and previously unquantified health effects, suggesting that the benefits of reducing mercury emissions may exceed previous estimates. At the same time, changes in the energy sector have altered the mix of fuels used to produce electricity, which impacts both the benefits and the costs of the regulation.

The Effect of Mixing Ratio of Two-Component Mixed Fuel on Diesel Spray and Combustion Characteristics

The Effect of Mixing Ratio of Two-Component Mixed Fuel on Diesel Spray and Combustion Characteristics

Brake power, brake spesific fuel consumption, dan brake thermal efficiency mesin diesel injeksi langsung berbahan bakar solarjatropa-butanol

Jatropha is proven to reduce dependence on diesel fuel. Jatropha oil is widely used as a mixture of diesel fuel. However, low heating value and high viscosity result in lower engine performance and higher carbon black emissions than pure diesel fuel. Alcohol groups such as butanol have low viscosity properties and oxygen and cetane numbers close to diesel fuel. The use of butanol as an additive to diesel-jatropha mixed fuels is expected to improve engine performance. This study aims to observe brake power, brake specific fuel consumption, and brake thermal efficiency of diesel engines using diesel-jatropha-butanol mixed fuel. Jatropha used 10%, 20% and 30%. While the butanol used is 5%, 10%, and 15% based on volume. The research increased in a brake power value of 2.22%. The decrease in brake specific fuel consumption was 4.81% and the increase in brake thermal efficiency was 10.85%. Keywords : jatropha, viscosity, performance, soot, butanol.

Lifespan cost analysis of alternatives to global sulphur emission limit with uncertainties

Following the updated global sulphur emission cap from 1 January 2020, shipowners are facing an increasing cost burden to comply with the new regulation in a tough shipping market. This research compares the lifespan costs of three main alternatives, all of which can satisfy the 2020 global sulphur emission regulation. A lifespan cost analysis model is built considering several cost items across the three alternatives, including the initial cost of investment, maintenance cost and fuel consumption cost. Two vessels with a capacity of 5000 and 10,000 TEUs are selected as case study vessels. The @risk software is utilized to conduct an uncertainty analysis with respect to the fuel price and the discount rate to test the three alternatives in different circumstances. The results indicate that the larger the vessel, the lower the discount rate, and the greater the price of Mixed Fuel Oil (a mixture of Very Low Sulphur Oil and Marine Gas Oil), the more attractive the scrubber option. Quantitatively, if the refining technology of low-sulphur fuel improves in the future and the price differential between Mixed Fuel Oil and Heavy Sulphur Fuel Oil decreases to $29 per ton for the 5000 TEU vessel or $27 per ton for the 10,000 TEU vessel, the fuel-switch alternative will be as competitive as the use of a scrubber in terms of the lifespan cost. Additionally, as the discount rate increases, the cost gap between the use of a scrubber and the other two alternatives gradually decreases.

Effect of downstream sinusoidal wall on mixing performance of hydrogen multi-jets at supersonic flow: Numerical study

Fuel mixing and penetration are known as substantial factor for advance of current scramjet engine. In this article, mixing and distribution of multi hydrogen jets are investigated under the impacts of downstream sinusoidal wall. This research tries to estimate the fuel jet interactions through the deflection of flow by downstream wavy wall. To perform our investigations, computational fluid dynamic with SST turbulence model is employed to simulate sonic multi hydrogen cross jets at supersonic air stream (M=4). The influences of fuel jet gaps and downstream wavy profile are comprehensively studied to disclose the importance of downstream on the fuel distribution and mixing region. Our results indicate that the fuel distribution in the downstream is substantially limited by increasing the frequency of downstream wavy wall. It is also noticed that the fuel concentration is decreased by increasing the jet space on the symmetry plane.

The effect of different fuels and clads on neutronic calculations in a boiling water reactor using the Monte Carlo method

In this study, a Boiling Water Reactor (BWR) modeling was done for the reactor core divided into square lattice 8 × 8 type using the Monte Carlo Method. Each of the square lattices in the reactor core was divided into small square lattices 7 × 7 type in groups of four. In the BWR designed in this study, modeling was made on fuel assemblies at pin-by-pin level by using neptunium mixed fuels as fuel rod, Zr-2 and SiC as fuel cladding, H2O as coolant. In fuel rods were used NpO2 and NpF4 fuels at the rate of 0.2%-1% as neptunium mixed fuels. In this study, the effect on the neutronic calculations as keff, neutron flux, fission energy, heating of NpO2 and NpF4 fuels in 0.2%-1% rates, and Zr-2 and SiC clads were investigated in the designed BWR system. The three-dimensional (3-D) modelling of the reactor core and fuel assembly into the designed BWR system was performed by using MCNPX-2.7.0 Monte Carlo method and the ENDF/B-VII.0 nuclear data library.

Influence of wood additives on pyrolysis products composition of mixed fuels based on 3B grade lignite

Experimental analysis of the influence of wood biomass on the composition of pyrolysis products of mixtures based on crushed coal (“Lignite” (3B)) and fine wood (lumber sawing waste) has been performed. Ash residue composition of the main components of fuels and mixtures based on them has been determined experimentally using X-Supreme 8000 element analysis device. Fuel mixture samples were used with a percentage of coal / wood – 100 % / 0 %, 90 % / 10 %, 75 % / 25 %, 50 % / 50 by weight. The experiments have been performed in an inert gas (Argon) environment at temperatures of 400 °C, 600 °C, and 800 °C. It has been established that during pyrolysis of two-component fuels based on 3B grade coal and dispersed wood biomass, there is growth of calcium and aluminum sulfates in the solid products of thermal decomposition of such mixtures (ash) due to a complex of reactions between pyrolysis products of coals and wood when the concentration of the wood component in the mixture changes from 10% to 50 %. Results of experimental studies allow substantiating previously formulated hypothesis about the mechanism of sequestering of sulfur oxides formed during coal pyrolysis as a result of interaction with gaseous products of thermal decomposition of wood and solid products of coal pyrolysis.

Photocatalytic performances of cobalt sulfides prepared by solution combustion synthesis using mixed fuels

Cobalt sulfide powders (CoS, Co9S8 and CoS1.97) were synthesized by solution combustion method using conventional and microwave heating routes. The powders were obtained using cobalt nitrate as both cobalt source and oxidizer together with proper amounts of thiourea as sulfidizing agent and glycine as an auxiliary reductant. Effects of thiourea and glycine amounts in conjunction with the type of combustion route, on the phase constituents, microstructure and optical properties were studied using infrared spectroscopy, thermal analysis, X-ray diffractometry, electron microscopy and diffuse reflectance spectrometry techniques. The results revealed that single phase cobalt sulfides can be delivered by precise adjustment of thiourea and glycine amounts and a proper heating (conventional or microwave) route. Co9S8 single phase was obtained using equal amounts of thiourea and glycine by both microwave and conventional heating modes. Using thiourea/glycine ratio of 1.5, leads to the formation of CoS1.97 single phase by conventional heating, while CoS was obtained when microwave heating was applied. Increasing the amount of thiourea caused particle size increment. Maximum photocatalytic degradation efficiency (89 and 89.5%) of methylene blue was obtained at pH = 9 for microwave combusted samples. Quenching tests in the presence of •OH− radical scavenger (isopropyl alcohol) showed that the major oxidizing species were • OH− radicals.

Long-term production technology mix of alternative fuels for road transport: A focus on Spain

Road transport is one of the main sources of greenhouse gas emissions due to the current dependence on fossil fuels such as diesel and gasoline. This situation needs to be changed through the retirement of fossil fuels and the implementation of alternative fuels and vehicles such as biofuels, battery electric vehicles, and fuel cell electric vehicles fuelled by hydrogen. Nevertheless, the environmental suitability of alternative fuels is conditioned by how they are produced. Through the case study of Spain, this article prospectively assesses – from a techno-economic and carbon footprint perspective– the production technology mix of alternative fuels from 2020 to 2050. The proposed energy systems optimisation model includes a large number of production technologies regarding biofuels (bioethanol, biodiesel, synthetic diesel/gasoline, and hydrotreated vegetable oil), electricity, and hydrogen. The combined study of these fuels provides a relevant framework to discuss the targets established for the road transport sector with a high level of detail not only regarding fuel type but also technology breakdown. The results show the relevance of second-generation biofuel production technologies in fulfilling the future biofuel demand. Regarding the extra electricity demand associated with the penetration of electric vehicles, the results suggest a key role of wind- and solar-based technologies in meeting such a need. Concerning hydrogen as an option to decarbonise the transport system, even though steam methane reforming is the most mature and cost-competitive production technology, hydrogen production would be satisfied through electrolysis in order to avoid relying on fossil resources as the main feedstock. Overall, this integrated approach to the long-term production technology mix of alternative fuels for road transport is expected to be relevant to a wide range of decision-makers willing to prospectively assess road transport systems from a technology perspective.

Turbines of the Caribbean: Decarbonising Suriname's electricity mix through hydro-supported integration of wind power

The Caribbean nation of Suriname has historically depended on a mix of hydropower and oil-based fossil fuels for meeting electricity needs. Continued reliance on fossil fuels poses challenges both for climate change mitigation and for energy security. This paper explores the potential for increasing the share of renewables in Suriname's electricity mix, with a special focus on the complementary role of existing hydropower and future wind power infrastructure. We show that these resources have great synergetic potential for displacing fossil fuel-based power generation. Flexible operation of the Afobaka hydropower plant, newly in full possession of Suriname, allows significant wind power integration without violating grid stability and associated power quality requirements. Considering the trade-off between displacing expensive fossil fuels and limiting wind power curtailment on Suriname's island-like grid, our results suggest that integrating wind power in the Surinamese electricity mix is economically advantageous up to a share of 20–30%, independently of near-term demand growth. These results have wider relevance for climate policy in various Caribbean countries and other island states with existing hydropower infrastructure and substantial wind/solar power potential, for which this study fills an important literature gap.

Environmental indicators of harmful emissions when working on mixed biofuels

This article presents the comparative environmental characteristics of diesel exhaust gases when running on biofuels and diesel fuel, which shows that the effect of using biofuels depends on the design features of the diesel motor and its operating mode, as well as on the properties of biofuels. Mixed fuels are obtained by mixing ethanol and vegetable oil. Both components are mixed with each other in any proportions without chemical reactions. The aggressiveness of the obtained mixed fuels on the surrounding nature is mainly determined by the amount of fuel contained in it.

Control Using Lookup Table on Dual Fuel Diesel Engines

Concerns about the availability of fuel oil reserves and air pollution have encouraged innovation to use of alternative fuels in diesel engines. Single fuel Diesel engines modified with a dual fuel, which is a mixture of diesel and gas. The problem of using mixed fuels is that the flashpoint of natural gas must meet the ignition requirements on diesel engines. The consumption of gas fuel in diesel engines, by the load, can continue to work using dual fuel. In this research, the gas fuel supply to control pattern used of dual-fuel with adjusted to the diesel engine load. The lookup table control method, one of the branches of expert system control, apply to change the valve opening of the gas valve. The efficiency of the control results being slightly lower than if manually controlled but still higher than if the fuel only uses diesel fuel.

Experimental investigation of effects of single and mixed alternative fuels (gasoline, CNG, LPG, acetone, naphthalene, and boron derivatives) on a commercial i-DSI engine

ABSTRACT A commercial i-DSI (Intelligent-Dual Sequential Ignition) engine is tested to investigate performance and emissions for single fuels and alternative fuels mixed into gasoline. The novelty of the study is the first time testing of the unconventional mixture of boron derivatives and quantification and comparison of real engine characteristics for 11 different fuels for the same commercial engine. Tested single fuels are gasoline (G100), CNG (CNG100), and LPG (LPG100). While the engine runs with gasoline, gaseous fuels are injected into the intake line at a mass rate of 10% CNG (CNG10) and 5% LPG (LPG5). The engine is also tested by adding 25–50% acetone (A25-A50) and 50% naphthalene (N50) into gasoline. Tests are also performed by mixing boron derivatives of borax-pentahydrate (BP), anhydrous-borax (AB), and boric-acid (BA) into gasoline. Tested fuels worsen engine performance compared to gasoline, except for brake specific fuel consumption (BSFC). There is a positive change in emissions for tested fuels compared to gasoline, except that NOx increases 4–5 times for CNG and LPG. One of the important findings is that, for boron-gasoline mixtures, the torque reduces by 4.0% for BP, 4.4% for AB, and 4.4% for BA. The volumetric efficiency decreases by 6.3% for BP, 7.3% for AB, and 8.5% for BA. The BSFC decreases 5.8% for BP, increases 0.4% for AB and decreases 15.2% for BA. Boron derivatives dissolved in gasoline diversely affect combustion and give some advantage in particular for BA and BP in terms of BSFC. In addition, boron-gasoline reduces the formation of HC and NOx.

Factors affecting in situ analysis of total petroleum hydrocarbons in contaminated soils by using a mid-infrared diffuse reflectance spectroscopy

The hand-held mid-infrared diffuse reflectance infrared Fourier transform (MIR-DRIFT) spectrometer was used to assess the applicability of on-site and real time monitoring of total petroleum hydrocarbons (TPH) in contaminated soils during site characterization and remediation. Field measurement devices (MIR-DRIFT and turbidimetric screening test kits) were used to analyze reference soils with concentration ranging from 713 to 54790 mg/kg and compared with the results by a gas chromatography/mass spectrometry method (GC/MS). In situ field measurement of 147 petroleum-contaminated soil samples from 11 contaminated sites was correlated with laboratory-determined soil TPH levels by GC/MS. The concentrations of TPH by MIR-DRIFT were significantly correlated to the concentrations of TPH by GC/MS. Detection of TPH by the MIR spectrometer was not affected by the weathering effects of diesel-contaminated soils. Soils contaminated by mixed fuels with high content of gasoline constituents may cause the potential interference in MIR measurement. In field practice, interference may be attributed to soil moisture, soil organic matter, and soil texture. Soil moisture below 5% is required to reduce variation of infrared beam reflected from high level of surface liquid. When measuring the contaminated soil with a high organic matter content, the results may be overestimated due to the possible effects of surface reflection and interference. Clay and partial silty clay soils were not suitable for MIR spectrometer detection due to a potential shielding effect to reduce the infrared radiation absorbed by TPH. Future research is warranted to reduce the variation caused by soil texture and heterogeneity in TPH prediction.