Combustion property analyses with variable liquid marine fuels in combustion research unit

The quality of ignition and co mbustion of four marine and power plant fuels were studied in a Combustion Research Unit, CRU. The fuels were low - sulphur Light Fuel Oil (LFO, baseline), Marine Gas Oil (MGO), kerosene and renewable wood - based naphtha. To meet climate change requirements a nd sustainability goals, combustion systems needs to be able to operate with a variety of renewable and ‘net - zero - carbon’ fuels. Due to the variations in the chemical and physical properties of the fuels, they generally cannot simply be dropped into existi ng systems. The aim of this research project was to understand how changes in fuel composition affect engine operation. The focus was on how various properties of the fuels impact on the combustion process – especially ignition delay and in - cylinder combus tion. The goal of the research project was to allow broad fuel flexibility without any or only minor changes to engine hardware. Before the engine tests, the CRU forms an easy and cost - effective device to find out the engine suitability of the fuel . The re sults showed that the ignition delay decreased expectedly with all fuels when the in - cylinder pressure and temperature increased. The differences in the maximum heat release rates between fuels decreased in high - pressure conditions. MGO had the shortest ig nition delay under both pressure and temperature conditions. Based on the CRU results MGO and kerosene are suitable to use in compression - ignited engines like the reference fuel LFO. In contrast renewable naphtha had a long ignition delay. If naphtha is us ed in a CI engine, the engine must be started and stopped with, e.g. LFO or MGO.fi=vertaisarvioitu|en=peerReviewed

Storage stability of rapeseed methyl ester stored in a sealed barrel for seven years

Received: March, 31st, 2021 ; Accepted: April, 24th, 2021 ; Published: November 15th, 2021 ; Correspondence: [email protected] stability is one of the main quality parameters related to fatty acid methyl esters (FAME) biofuels. The deterioration of biofuels´ properties during storage is a more serious issue than with conventional fuels. In particular, lengthy storage threatens the oxidative stability of FAME fuels because factors such as the presence of air, elevated temperatures or presence of metals promote the oxidation process. Consequently, the acceptable storage time for FAME fuels is generally regarded to be regrettably short, at no more than six to12 months. However, storage conditions play an important role in determining actual storage stability. This study aimed to investigate and evaluate any deterioration in the quality of rapeseed methyl ester (RME) fuel that has been stored for as long as seven years in adequate storage conditions. The fuel was stored in the dark, contained in a sealed steel barrel in an insulated shipping container outdoors. The temperature of the container varied with seasonal fluctuation, but the fuel never froze during storage. The study analysed six key fuel properties of the RME: ester content; water content; density; kinematic viscosity; oxidation stability index; and acid number. The analyses were conducted immediately after opening the barrel, and again after two months of storage in a laboratory. The results were compared to those measured for the fresh fuel, seven years earlier. The comparison of the results indicate that the fuel quality had suffered no serious deterioration during the seven-year period

Aqueous modification of chitosan with itaconic acid to produce strong oxygen barrier film

In this study, the chemical modification of chitosan using itaconic acid as a natural-based unsaturated dicarboxylic acid was investigated. In an aqueous environment, the amine group of chitosan reacts with itaconic acid to produce a chitosan derivative with pyrrolidone-4-carboxylic acid group. On the basis of the elemental analysis, 15 of the amine groups of chitosan reacted, thus creating modified chitosan with amine and carboxylic acid functionalities. Due to the presence of amine and carboxylic acid groups, the surface charge properties of the chitosan were notably altered after itaconic acid modification. In an aqueous solution, the modified chitosan exhibited zwitterionic properties, being cationic at low pH and turning anionic when the pH was increased over 6.5, whereas the original chitosan remained cationic until pH 9. Furthermore, it was demostrated that the modified chitosan was suitable for the preparation of a self-standing film with similarly high transparency but notably higher mechanical strength and oxygen barrier properties compared to a film made from the original chitosan. In addition, the thermal stability of the modified chitosan film was higher than that of the original chitosan film, and the modified chitosan exhibited flame-retardant properties

One-step method for the preparation of cationic nanocellulose in reactive eutectic media

A novel method based on the use of reactive eutectic media for the extraction of cellulose nanocrystals and their functionalization with positively charged functional groups in a one-step procedure is presented. With its ability to form strong hydrogen bonds, the eutectic medium serves as a cellulose-solubilizing agent, while the presence of a Leuckart reagent provides the reactivity toward the reductive amination of carbonyl groups in the cellulose chains. In the proposed method, amorphous cellulose domains are partially dissolved by undergoing aminolysis, resulting in the formation of water-dispersible nanocellulose products with high crystallinity.<br

Antioxidant studies for animal-based fat methyl ester

The aim of this study was to test an antioxidant, BioSineox, for animal-based fat methyl ester, AFME, in order to determine the optimal concentration of this antioxidant for meeting the six-hour oxidation stability requirement as set in the EN 14214:2010 standard. Oxidation stability was measured using a Biodiesel Rancimat 873, which meets the requirements of the EN 14112 standard. The variety of raw materials used in the production of methyl esters, i.e. biodiesels, renders a variety of fatty acid profiles. Consequently, the reaction of biodiesels with various antioxidants must be individually tested for each combination. Before the antioxidant is added during the manufacturing process, it must be tested in laboratory conditions. As the main result of this study it can be stated that the process requires a relatively high (2,000 ppm) BioSineox concentration in order for the biodiesel to meet the six-hour oxidation stability requirement. In March 2013, the standard EN 14214:2010 was replaced by the EN 14214:2012. One of the changes was an increase in the oxidation stability requirement from 6 hours minimum to 8 hours minimum. To reach this target, the concentration of the antioxidant must be further increased.© 2014 The Authors. This is an open access journal distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence https://creativecommons.org/licenses/by-nc-nd/4.0/fi=vertaisarvioitu|en=peerReviewed

Exhaust particle number of a non-road diesel engine fuelled by methyl esters with different fatty acid compositions

ArticleThe main aim of this study was to find out how methyl esters with different fatty acid compositions affect the exhaust particle numbers. Along with fossil diesel fuel oil (DFO) and renewable diesel (HVO), a high-speed non-road diesel engine was fuelled by rapeseed (RME) and soybean (SME) methyl esters. Particle numbers within the size range of 5.6–560 nm were measured by means of an engine exhaust particle sizer (EEPS). The exhaust smoke, gaseous emissions and the basic engine performance were also determined. During the measurements, the 4-cylinder, turbocharged, intercooled engine was run according to the non-road steady cycle. Methyl esters reduced particles within the size range of 70 to 200 nm. For RME and SME, both positive and significant correlations were found between the sum of the particle numbers detected above the size category of 23 nm and methyl palmitate (C16:0), methyl stearate (C18:0) and methyl linoleate (C18:2) contents at 10% load at rated speed. In terms of nitrogen oxide (NOx) and hydrocarbon (HC) emissions, HVO was beneficial while carbon monoxide (CO) emission was the lowest with DFO. The level in smoke emission was negligible

Effects of storage on the properties of rapeseed oil and alcohol blends

Received: February 1st, 2021 ; Accepted: May 2nd, 2021 ; Published: May 4th, 2021 ; Correspondence: [email protected] viscosity and density are important fuel properties because they influence fuel atomisation during injection into the engine cylinder. The viscosity and density of neat vegetable oils usually are too high to allow optimal use of these oils in compression ignition engines. Blending vegetable oils with alcohols can improve these properties, but it is not known whether the blend properties remain stable during storage. This study measured kinematic viscosity (at 40 °C), density (at 15 °C) and surface tension of rapeseed oil-alcohol blends that had been stored in closed borosilicate glass bottles at room temperature in the dark for 49 weeks. The values were compared with those of the fresh blends. Further measurements of oxidation stability for the rapeseed oil and the blends were taken after 72 weeks of storage. The blends consisted of rapeseed oil with ethanol at 5 vol–%, and rapeseed oil with 1–butanol at 5 vol–%, 10 vol–%, 20 vol–% and 30 vol–%. All in all, the observed changes during storage were small. Density values deviated by less than 1%, surface tension by no more than 3% and kinematic viscosity differed from the fresh blends’ values by 1% to 8%. Surface tension had increased in some blends and decreased in others. Kinematic viscosity rose in all blends, with the smallest increase measured for the rapeseed oil–butanol 30 vol–% blend. This blend also showed the best oxidation stability, which was close to six hours

Properties of local produced animal-fat based biodiesel and its blend with fossil fuel

In the near future, more emphasis must be put on reducing greenhouse gas (GHG) emissions in road transportation, house heating, agricultural activities, marine transport etc. This study concentrated on the use of alternative fuels in engine - driven applicat ions of non - road machineries and decentralized energy production . Today, the engines are mainly designed for crude oil derived fuels and liquid renewable fuels are blended with crude oil based fuels to fulfill the requirements of renewable energy usage. Du e to the environmental reasons on one hand and to the agricultural needs, on the other hand , different blends of bio - and fossil fuels are becoming more popular. In Europe, the maximum FAME content in diesel fuel is 7 vol% according to the EN 590:2013 but higher percentages are also available and targeted around the world. For example in the United States, the 20% blend fraction is becoming more common. For these reasons, B20 fuels were chosen to be investigated in this study. Special emphasis was put on im proving blending issues since fuel blending may cause some operating risks. The main aim was to research widely the properties of animal - fat based methyl ester (AFME) and B20 fuel blend produced from it. AFME is a waste based fuel and produced in Ostroboth nia region, Finland. The aim was to find out in which engine applications the fuels are feasible and investigate if the fuels fit in the quality of automotive fuel Standards. According to the results, AFME is a feasible option to increase self - sufficient e ne rgy production in Ostrobothnia.fi=vertaisarvioitu|en=peerReviewed

Effects of storage on the properties of rapeseed oil and alcohol blends

Received: February 1st, 2021 ; Accepted: May 2nd, 2021 ; Published: May 4th, 2021 ; Correspondence: [email protected] viscosity and density are important fuel properties because they influence fuel atomisation during injection into the engine cylinder. The viscosity and density of neat vegetable oils usually are too high to allow optimal use of these oils in compression ignition engines. Blending vegetable oils with alcohols can improve these properties, but it is not known whether the blend properties remain stable during storage. This study measured kinematic viscosity (at 40 °C), density (at 15 °C) and surface tension of rapeseed oil-alcohol blends that had been stored in closed borosilicate glass bottles at room temperature in the dark for 49 weeks. The values were compared with those of the fresh blends. Further measurements of oxidation stability for the rapeseed oil and the blends were taken after 72 weeks of storage. The blends consisted of rapeseed oil with ethanol at 5 vol–%, and rapeseed oil with 1–butanol at 5 vol–%, 10 vol–%, 20 vol–% and 30 vol–%. All in all, the observed changes during storage were small. Density values deviated by less than 1%, surface tension by no more than 3% and kinematic viscosity differed from the fresh blends’ values by 1% to 8%. Surface tension had increased in some blends and decreased in others. Kinematic viscosity rose in all blends, with the smallest increase measured for the rapeseed oil–butanol 30 vol–% blend. This blend also showed the best oxidation stability, which was close to six hours

Methanol-HVO blends for efficient low-temperature combustion: analytical research on fuel properties

Received: January 31st, 2023 ; Accepted: April 15th, 2023 ; Published: August 14th, 2023 ; Correspondence: [email protected] low-temperature combustion (LTC) engines can accommodate ultra-high efficiency with near-zero NOx and PM emissions. Reaction kinetics is the governing mechanism in LTC. Onboard fuel reactivity control is, thus, becoming an interesting concept that ultimately provides pathways toward a fully fuel-flexible engine. No matter the technical realisation - in-cylinder blending or pre-blending/emulsification - the reactivity control requires fuels with complementary properties. Methanol and hydrotreated vegetable oil (HVO) seem to be one of the most promising, yet under-studied combination for LTC engines. They are both renewable and can be mixed together. Methanol’s high knock resistance and large latent heat of evaporation enable a wide engine load range, with a propensity to reduce NOx emissions and mitigate thermal or mechanical stress. The same properties on the other hand require highly reactive fuel to enable the mixture to self-ignite controllably in LTC conditions. HVO is amongst the most reactive renewable alternatives and its clean paraffinic structure further mitigates particle matter formation. - Importantly, in pre-blending HVO emulsification can resolve the lubricity issues of methanol. In this paper, the aim was to study the engine-relevant properties of HVO-methanol fuel blends. The analysed properties were the distillation properties, density, kinematic viscosity, cetane index, and flash point. Based on the results, the suitability of the chosen blend shares for LTC concepts was evaluated