Search

This paper investigates overall performance of a small-scale electrolytic hydrogen production, using an Organic Rankine Cycle (ORC) driven by a parabolic trough collector (PTC) plant, under the Algerian Sahara climate. The evaluations of PTC plant and the thermodynamic analysis of the ORC are performed by SAM and EES software, respectively. These results are then used for hydrogen production calculations. Among three southern cities investigated, Ghardaia is most favorable site to implement the proposed system. For the ORC plant, eight alternative working fluids (butane, n-pentane, isopentane, benzene, toluene, R245fa, R123 and water), are considered for comparison. As results, the highest output power and plant efficiency are achieved with benzene during May to August with maximum power of 8.74 kW and cycle efficiency of 21.65% during July. The highest hydrogen production rate is achieved in July with 847 Nm3 using the high temperature water vapor electrolyzer and benzene as working fluid.

This paper focuses on optimizing the hydrogen TMI (timed manifold injection) system through valve lift law and hydrogen injection parameters (pressure, injection inclination and timing) in order to prevent backfire phenomena and improve the volumetric efficiency and mixture formation quality of a dual fuel diesel engine operating at high load and high hydrogen energy share. This was achieved through a numerical simulation using CFD code ANSYS Fluent, developed for a single cylinder hydrogen-diesel dual fuel engine, at constant engine speed of 1500 rpm, 90% of load and 42.5% hydrogen energy share. The developed tool was validated using experimental data. As a results, the operating conditions of maximum valve lift = 10.60 mm and inlet valve closing = 30 °CA ABDC (MVL10 IVC30) prevent the engine from backfire and pre-ignition, and ensure a high volumetric efficiency. Moreover, a hydrogen start of injection of 60 °CA ATDC (HSOI60) is appropriate to provide a pre-cooling effect and thus, reduce the pre-ignition sources and helps to quench any hot residual combustion products. While, the hydrogen injection pressure of 2.7 bar and an inclination of 60°, stimulate a better quality of hydrogen-air mixture. Afterwards, a comparison between combustion characteristics of the optimized hydrogen-diesel dual fuel mode and the baseline (diesel mode) was conducted. The result was, under dual fuel mode there is an increase in combustion characteristics and NOx emissions as well as a decrease in CO2 emissions. For further improvement of dual fuel mode, retarding diesel start of injection (DSOI) strategy was used.

Hydrogen is clean energy career that can be produced through renewable energies. Solar plant with parabolic trough concentrators systems is a one of the most promising renewable energies sources for producing energy. This technology is tightly related to the solar insolation levels. Algeria has a potential of Direct Normal Insolation (DNI) that exceeds 2000 kWh/m2/year with an average daily sunlight duration that exceeds 10 h. Thus are the key features for the development of Solar plant. This paper deals with numerical simulations of a small-scale electrolytic hydrogen production using solar plant with parabolic trough concentrators via an Organic Rankine Cycle. The city of Ghardaia, located in south of Algeria was selected as a study site. The results have demonstrated among the three organic working fluids (Benzene, Toluene, R-123) selected, benzene is the fluid offering the best efficiency. Moreover, the amounts of hydrogen produced are closely related to the organic fluid used as well as the intensity of the solar radiation.

The main interest of the Wankel rotary engine is its higher power density as compared to similar conventional engine. However, the unusual geometry of the Wankel engine affects negatively the engine economy and the exhaust emissions. The knowledge of the rotary Wankel engine drawbacks and fuel characteristics can help to choose which fuel can achieve the best performance with that kind of engine. The aim of this paper is to compare the experimental results of the performance of a monorotor Wankel engine fuelled with gasoline, ethanol and then after hydrogen addition to each fuel used, at lean operating condition and full load regime. Testing were carried out under constant engine speed of 3000 rpm, fixed spark timing of 15° BTDC, at lean to ultra lean and full load conditions. The test results have shown that pure ethanol burns more efficiently than gasoline. Moreover, the addition of hydrogen helps to achieve better brake mean effective pressure, thermal efficiency and reduce the fuel consumption for both fuel, however, this improvement is more significant for gasoline engine.

The phenol biodegradation by Ca-alginate immobilized indigenous bacteria was performed in batch system. The effects of some operational parameters were evaluated, including % weight of alginate, calcium and CaCl

In this paper, a gasoline Wankel engine was modified and equipped with self-developed hybrid electronic control unit to experimentally investigate the effect of hydrogen-enrichment level on combustion characteristics of a gasoline Wankel engine at wild open throttle position and lean burn regime. Testing were carried out under constant engine speed of 3000 rpm and the lean operating limit of the original gasoline engine. The spark timing was set at 15 °BTDC. The hydrogen energy fraction in the intake was gradually increased from 0% to 10%. The results showed that hydrogen enrichment was effective on improving the combustion process through the shortened of the flame development and the flame propagation periods, advancing the central heat release, increasing the HRRmax and reducing the cyclic variation proportionally to the amount of hydrogen added to the air fuel mixture. Furthermore, increasing hydrogen fraction in the intake improves the engine economy by reducing the cooling loss.

This paper experimentally investigates the effect of hydrogen addition on the lean burn capability of an ethanol-fuelled Wankel rotary engine at Wide Open Throttle (WOT) operating conditions in order to observe the resultant engine economy and the hydrocarbon emissions. During the tests, a monorotor Wankel engine operating at 3000 rpm was modified to run on an ethanol–hydrogen blend with 0% and 5% hydrogen energy fractions in the intake. The excess air ratio was varied from 1.7 to the Ultra-Lean Operating Limit (ULOL) of a specified hydrogen–ethanol mixture. With hydrogen addition, the test results show that the ultra-lean operation limit of pure ethanol fuelled Wankel engine was extended and the engine stability was enhanced. Moreover, the engine fuel economy was increased and Hydrocarbons (HC), Carbon Monoxide (CO) and Carbon Dioxide (CO2) emissions were reduced after hydrogen addition.

In this paper, the effect of hydrogen addition to ethanol in a monorotor Wankel engine at wide open throttle position and in an ultra-lean operating regime was experimentally investigated. For this aim, variation of hydrogen enrichment levels on the ethanol engine performance and emissions were considered. Experiments were carried out under a constant engine speed of 3000 rpm and fixed spark timing of 15 °BTDC. The test results showed that hydrogen enrichment improved the combustion process through shortening of the flame development and flame propagation periods and reducing the cyclic variation. Furthermore, the reduction of burn duration with the increase of hydrogen fraction enhances the thermal efficiency, reducing the brake-specific energy consumption, as well as reducing the unburned hydrocarbons emissions of the Wankel engine.

In this paper, an experimental investigation of the effect of hydrogen enrichment on a gasoline Wankel engine's Lean Operation Limit (LOL) was performed. A monorotor Wankel engine operating at 3000 rpm and wide open throttle was modified to run on gasoline and hydrogen blends. Excess air ratio varying from stoichiometric mixtures to the engine lean burn limit with 0%, 3% and 6% of hydrogen energy fractions in the intake were investigated. The experimental results proved that adding hydrogen to gasoline extends the original engine LOL while improving the engine stability. An increased thermal efficiency and reduced burn duration, brake specific energy consumption, and HC, CO and CO2 emissions were observed with hydrogen enrichment. Furthermore, the extension of the engine LOL with hydrogen addition could potentially control the NOx emissions of a gasoline Wankel engine to very low levels without using a three-way catalytic converter.

The Wankel rotary engine is a potential alternative to the reciprocating engine in hybrid applications because of its favorable energy to weight ratio. In this study, a Wankel rotary engine was modified to run on a hydrogen–gasoline blend. Hydrogen enrichment improved the performance of a lean-burn spark-ignition rotary engine operating at high speed and wide open throttle conditions with the original ignition timing, using 0%, %2, 4%, 5%, 7%, and 10% hydrogen energy fractions at the intake. The experimental results showed that adding hydrogen to gasoline in the engine improved the thermal efficiency and the power output. Hydrocarbon and carbon monoxide emissions were reduced while nitrogen oxide emissions increased with the increase of hydrogen fraction.

The Climate change has seriously impacted on the environment of the human beings. Though, most of the climatic warming that has occurred has been caused by human activities, in particular the burning of fossil fuels that generate the greenhouse gas emissions. However, in urban area, the transport sector is one of the most important causes of the high levels of atmospheric pollution: greenhouse gas and fine particulate matter emitted by the gasoline and diesel engines. The introduction of alternative fuel in the transport sector which is less pollutant, economically more affordable and more available is an alternative quite interesting to reduce air pollution while allowing economic and social development of Algeria. Using Compressed Natural Gas ‘CNG’ for vehicle is an alternative which is environmentally friendly as well as economically and energetically interesting, it is also in accordance with the world energy tendency which sustains the future use of gaseous fuels that are subscribed in the decarbonization process of the energetic systems (reducing the fuels carbon content). In this item, an overview of the Algerian automobile fleet will be exposed. And the economic, energetic and environmental matters of the introduction of the CNG as fuel in the Algerian transport sector will be discussed.

The Algerian transport sector is still largely dependent on petroleum. Pollution emitted by this sector is constantly increasing with the expansion of the automobile fleet. Thus, there is a pressing need for use of cleaner and economically viable alternative fuels. Therefore, the use of Hydrogen enriched Compressed Natural Gas (HCNG) is expected to play a significant role to reach this target. When hydrogen and natural gas are used together in an internal combustion engine, large benefits are possible. Algeria has significant resources and potential to introduce this new fuel. The development of HCNG as a transportation fuel allows an entry point for hydrogen in the transportation sector. The aim of this paper is to discuss strategic ways to introduce HCNG as road fuel, in Algeria. Two fundamental strategic elements were designed to introduce the Hydrogen Enriched Natural Gas as a transportation fuel. These are, the development of compressed natural gas as a road fuel, and the completion of the MedHySol project. The MedHySol project includes the production and the distribution of solar produced hydrogen, and involves the project HySolThane intended for the development of HCNG fuel road with 8% vol of Hydrogen in Natural Gas.