Parties to the 2015 Paris Agreement pledged to limit global warming to well below 2 °C and to pursue efforts to limit the temperature increase to 1.5 °C relative to pre-industrial times
. However, ...fossil fuels continue to dominate the global energy system and a sharp decline in their use must be realized to keep the temperature increase below 1.5 °C (refs.
). Here we use a global energy systems model
to assess the amount of fossil fuels that would need to be left in the ground, regionally and globally, to allow for a 50 per cent probability of limiting warming to 1.5 °C. By 2050, we find that nearly 60 per cent of oil and fossil methane gas, and 90 per cent of coal must remain unextracted to keep within a 1.5 °C carbon budget. This is a large increase in the unextractable estimates for a 2 °C carbon budget
, particularly for oil, for which an additional 25 per cent of reserves must remain unextracted. Furthermore, we estimate that oil and gas production must decline globally by 3 per cent each year until 2050. This implies that most regions must reach peak production now or during the next decade, rendering many operational and planned fossil fuel projects unviable. We probably present an underestimate of the production changes required, because a greater than 50 per cent probability of limiting warming to 1.5 °C requires more carbon to stay in the ground and because of uncertainties around the timely deployment of negative emission technologies at scale.
In many countries, Heavy Fuel Oil (HFO) is still a common fuel in industrial applications due to its low price and high energy density. However, the complex and incomplete combustion of HFO results ...in high levels of emissions and low efficiency, which causes the search for additives to improve its properties without affecting its heating value. The present paper aims to use as an additive the liquid fraction from pyrolysis of the polystyrene for fuel oil, replacing conventional additives such as cutter stock, improving its fluidity without using heat to pump it. As for pyrolysis for obtaining pyrolytic oil, the effect of temperature on the chemical composition of the liquid fraction from the thermal pyrolysis of compact polystyrene was studied. PS pyrolysis was carried out in a temperature range between 350 to 450 °C at a heating rate of 15 °C min−1 in a batch type reactor, with a condensation system, in order to analyze the best fraction liquid yield. At 400 °C we obtained a liquid fraction of 81%. This product presented a kinematic viscosity of 1.026 mm2 s−1, a relative density of 0.935, a flash point of 24 °C, and a gross heating value of 48.5 MJ kg−1. Chromatographic analysis indicates that 75% by mass of the components corresponds to C6 to C20 hydrocarbons, showing the high generation of isomers of the polystyrene monomer and aromatic compounds. The product obtained is mixed with base fuel oil at 60 °C at 250 rpm for a period of one hour, in percentages of 10 to 50% by mass. The 10% mixture has properties very close to those required by the standard fuel oil, presenting a viscosity of 108 mm2 s−1 that adjusts to the requirements in burners for industrial applications; additionally, it has a Sulphur content lower than that of fuel oil without affecting its heating value.
Heavy fuel oil has an energy density content comparable to distillate fuels but a very high viscosity that necessitates extra heating before spray combustion inside a boiler. Heavy fuel oil is also ...characterized by high asphaltenes, carbon residues, trace metals, such as vanadium and nickel, fuel-bound nitrogen, and sulfur. Asphaltenes are heavy polycyclic aromatic compounds with embedded heteroatoms and significantly affect the physico-chemical properties of heavy fuels; this makes them very difficult to burn and leads to the formation of large cenospheres (lightweight, inert, hollow spheres), due to an inefficient burning process. The primary goal of this study is to experimentally investigate the influence of the asphaltene concentration on the combustion of HFO under a swirling flame, finally reducing gaseous and solid pollution. We tested HFO samples containing asphaltene concentrations of 4, 6, 8, 16, and 24 wt.%, prepared by blending the light oil of diesel and pure asphaltenes with HFO. This work provides quantitative information about the effect of different asphaltene contents on the fuel properties of viscosity, density, heating value, thermogravimetry with air and N2, and swirling flame combustion characteristics, including the analysis of gaseous and solid particle emissions. The results indicated that the high asphaltene content in the fuel was the critical factor for the high viscosity and incomplete combustion and also increased the density of the fuel sample. Reducing the asphaltene content in HFO improves its spray characteristics and combustion performance and reduces the solid emissions containing sulfur and metal elements.
Facilitated by a receding sea ice extent, new and shorter routes have led to increased maritime traffic in Arctic areas with an inherent risk for oil spills along Arctic rocky shorelines. To estimate ...natural oil removal under Arctic conditions, a crude oil and a heavy fuel oil were applied to slate tiles, mimicking rocky shore substratum, and placed at four levels within and just above the tidal zone on two rocky shorelines in West Greenland. Tiles were regularly sampled (within 95 days) to determine natural oil removal and chemical composition of the remaining oil. We found that natural oil removal on the rocky shorelines depends on (1) level position on the shoreline, i.e., within and above the tidal zone where ample exposure to water and wave-wash increases oil removal rate and efficiency, and (2) physical and chemical oil properties with the crude oil being removed more readily than the heavy fuel oil. These findings can help improve the risk assessment of oil spills in Arctic areas and facilitate the development of effective oil spill response strategies in Arctic seas.
Most climatic changes are not just the result of human activity, but also of business models that harm the environment. An attempt to attain an ecological balance is an answer to the challenge posed ...by this situation. The combustion of liquid fuels results in the atmospheric emissions of pollutants, such as nitrogen oxides (NOx), sulfur dioxide and hydrocarbons. To reduce emissions of these pollutants and at the same time attain an ecological balance, specific modifiers are applied. This paper presents an analysis of the energy efficiency and ecological efficiency of fuel oil combustion in power plant boilers based on the results of tests carried out by the present authors, in which a Fe/Mg/Ce modifier was used. The tests were carried out for system capacities ranging from 1 to 5 MW. It was found that savings on fuel, which resulted from the implementation of a system for the control and supervision of power plant operation, were in the range of 4 to 6%, and those resulting from the use of the combustion modifier were from 2 to 4%. Moreover, it was found that the system designed to improve efficiency also provided the extra result of reducing CO2 emission and equivalent emission (SO2, NO2, and particulate matter).
Glucose, which can be obtained from the biomass directly, was added into the heavy fuel oil in the form of an aqueous solution to prepare a novel alternative emulsified fuel. The effects of different ...components (water, glucose and surfactant) on the droplet size distribution, the stability and the viscosity-temperature characteristics were studied experimentally. Results show that the increases in both the water concentration (0–40v/v%) and the hydrophile-lipophile balance (HLB) value (4.3–14.3) have the negative influence on the stability. By contrast, with the enhanced glucose blend ratio (0–40%), the stability and the homogeneity present the rising trends before they are decreased. It is worth noting that the long-term stability (85 °C, 30 days without separation) along with the minimum mean droplet size can be obtained at the 30% glucose blend ratio. Besides, the long-term stability cannot be not obtained at both surfactant concentration of 1% and 5%. The viscosity of the emulsion with surfactant is reduced in the range of 25–35 °C but increased in the range of 60–95 °C compared with that of emulsion without surfactant. Furthermore, there exists the quite slight change of the viscosity with the addition of glucose.
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•Blending glucose in dispersed phase reduced the mean droplet size.•When blending 30% glucose, the none-surfactant-emulsion stabled for 30 days at 85 °C.•The addition of glucose had little effect on dynamic viscosity of heavy oil emulsion.
In this work, we present hardware and firmware design and preliminary testing results for a noninvasive device for measuring fuel oil consumption in fuel oil vented heaters. Fuel oil vented heaters ...are a popular space heating method in northern climates. Monitoring fuel consumption is useful to understanding residential daily and seasonal heating patterns and understanding the thermal characteristics of buildings. The device is a pump monitoring apparatus (PuMA) that employs a magnetoresistive sensor to monitor the activity of solenoid driven positive displacement pumps, which are commonly used in fuel oil vented heaters. PuMA accuracy for calculating fuel oil consumption was evaluated in a lab setting and found to vary up to 7% from the measured consumption value during testing. This variance will be explored more in field testing.
A biomimetic catalytic system was designed for aerobic oxidative desulfurization via coupling polyoxometalate (POM) with carboxylic acid based deep eutectic solvent (DES), following multi-step ...electron transfer mechanism. The difference in desulfurization efficiency was attributed to the distinguished intrinsic oxidation ability of organic acid in DES.
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•A biomimetic catalytic system coupling POMs with DESs was proposed.•The structure-function relationship was unveiled in ODS.•This system exhibited unique naphthaline-indole-resistant ability.•This work provides some guidance for the design of robust catalytic system.
Organic sulfides in fuel oil result in the formation of environmentally hazardous sulfur oxide through the combustion in vehicle engine. Oxidative desulfurization is considered to be an effective technique to eliminate sulfides in fuel oil, whose core is the construction of efficient catalytic systems under mild conditions. Herein, a biomimetic catalytic system was designed for aerobic oxidative desulfurization via coupling ammonium molybdate polyoxometalate with four different deep eutectic solvents (DESs), obeying multi-step electron transfer mechanism. It was found that the desulfurization efficiency was not directly associated with conductivity, viscosity and hydrogen-bonding strength. In combination with density functional theory (DFT) calculation, the difference in desulfurization efficiency was ascribed to the distinguished intrinsic oxidation ability of organic acid in DES. The optimal catalytic system not only could resist the adverse effect of naphthaline and indole within suitable concentration scope, but also did not show obvious decrease in desulfurization performance after ten runs. More importantly, deep desulfurization was still afforded for actual diesels using this catalytic system, indicating its enormously potential applications on an industrial level under mild conditions.
Saturated, aromatic, resin, and asphaltene (SARA) group and fractional composition of 14 samples of marine residual fuel oils and components suitable for their production is studied. Analysis of the ...results of laser Fourier-difractometric study of solutions of these samples in isooctane made it possible to develop a quantitative method of assessment of their colloidal stability. Correlative relationships of the composition and colloidal stability of the studied asphaltene-containing and asphaltene-free petroleum products are derived. The inapplicability of the term “straight-run” for assessment of colloidal stability of residual fuels is shown experimentally.
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