• Energy Research

Diminishing fuel resources and stringent emission mandates have demanded cleaner combustion and increased fuel efficiency. Three water addition rates, i.e., 2, 4, and 6 wt% in biodiesel-diesel blend (B5) was investigated herein. Combustion characteristics of the emulsified fuel blends were compared in a naturally-aspirated diesel engine at full load and different engine speeds. More specifically, biodiesel was produced from waste cooking oil (WCO) and to further increase waste utilization, recycled biodiesel wastewater was used as additive in B5. The result obtained showed that low-level water addition (i.e., 2 and 4 wt%) in B5 led to different results from those obtained using higher water addition rates (i.e., >5 wt%) reported by the previous studies. In more details, the findings of the present study revealed that low level water addition in B5 could considerably reduce CO, HC, CO2, and NOx emissions. Among water-containing B5 fuel emulsions, the optimal water addition level in terms of engine performance parameters and emissions was found at 4 wt%. In particular, the emitted CO2, HC, and NOx were decreased by over 8.5%, 28%, and 24%, respectively, at maximum speed of 2500 rpm.

Diminishing fuel resources and stringent emission mandates have demanded cleaner combustion and increased fuel efficiency. Three water addition rates, i.e., 2, 4, and 6 wt% in biodiesel-diesel blend (B5) was investigated herein. Combustion characteristics of the emulsified fuel blends were compared in a naturally-aspirated diesel engine at full load and different engine speeds. More specifically, biodiesel was produced from waste cooking oil (WCO) and to further increase waste utilization, recycled biodiesel wastewater was used as additive in B5. The result obtained showed that low-level water addition (i.e., 2 and 4 wt%) in B5 led to different results from those obtained using higher water addition rates (i.e., >5 wt%) reported by the previous studies. In more details, the findings of the present study revealed that low level water addition in B5 could considerably reduce CO, HC, CO2, and NOx emissions. Among water-containing B5 fuel emulsions, the optimal water addition level in terms of engine performance parameters and emissions was found at 4 wt%. In particular, the emitted CO2, HC, and NOx were decreased by over 8.5%, 28%, and 24%, respectively, at maximum speed of 2500 rpm.

In this study, the effects of equivalence ratio and biochar particle size on high heating value, gas composition, carbon conversion, and gas production from the empty fruit bunch biochar were experimentally investigated in a fluidized bed reactor. Equivalence ratio varied from 0.1 to 0.34, while the size varied from 0.2 mm ≤ s ≥ 1 mm. It was observed that the syngas production increased as the air flow rate increased until equivalence ratio was equivalent to 0.24 and finally decreased with increasing equivalence ratio. In addition, the high heating value of syngas also decreased as equivalence ratio increased. The increase in the particle size from 0.2 mm ≤ s ≥ 1 mm decreased the H2 yield from 34.75 to 25.3%, and decreased the overall syngas production and high heating value. The produced syngas revealed a high heating value in the range of 22.6–52.9 MJ/KG. Meanwhile, the maximum char to gas conversion efficiency achieved was 80.2%. A hydrogen-rich gas was successfully produced through air gasification at...

In this study, the effects of equivalence ratio and biochar particle size on high heating value, gas composition, carbon conversion, and gas production from the empty fruit bunch biochar were experimentally investigated in a fluidized bed reactor. Equivalence ratio varied from 0.1 to 0.34, while the size varied from 0.2 mm ≤ s ≥ 1 mm. It was observed that the syngas production increased as the air flow rate increased until equivalence ratio was equivalent to 0.24 and finally decreased with increasing equivalence ratio. In addition, the high heating value of syngas also decreased as equivalence ratio increased. The increase in the particle size from 0.2 mm ≤ s ≥ 1 mm decreased the H2 yield from 34.75 to 25.3%, and decreased the overall syngas production and high heating value. The produced syngas revealed a high heating value in the range of 22.6–52.9 MJ/KG. Meanwhile, the maximum char to gas conversion efficiency achieved was 80.2%. A hydrogen-rich gas was successfully produced through air gasification at...

A comprehensive experimental study was accomplished to assess the influence of fuel additive in the formulation of water-in-diesel (W/D) nanoemulsions using surfactant in two ways, with and without including fuel additive, and a comparison is made with neat diesel. A range of surfactant concentration (0.25% to 0.40% v/v) was used with varying water concentration (0.7% to 1% v/v) to prepare W/D nanoemulsion fuel. High energy emulsification process was employed for this purpose and attempts to compare between both ways, physical and experimental observations were considered. The destabilization methods, mainly Oswald ripening, was discussed to investigate the stability. The influence of fuel additive over the characteristics of nanoemulsion such as droplet size, stability, viscosity, emulsion calorific value was studied in detail. The droplet size of W/D nanoemulsion fuel was found to be in the range approximately from 2 to 200 nm in both procedures. The engine test bed was utilized to combust the emulsion ...

A comprehensive experimental study was accomplished to assess the influence of fuel additive in the formulation of water-in-diesel (W/D) nanoemulsions using surfactant in two ways, with and without including fuel additive, and a comparison is made with neat diesel. A range of surfactant concentration (0.25% to 0.40% v/v) was used with varying water concentration (0.7% to 1% v/v) to prepare W/D nanoemulsion fuel. High energy emulsification process was employed for this purpose and attempts to compare between both ways, physical and experimental observations were considered. The destabilization methods, mainly Oswald ripening, was discussed to investigate the stability. The influence of fuel additive over the characteristics of nanoemulsion such as droplet size, stability, viscosity, emulsion calorific value was studied in detail. The droplet size of W/D nanoemulsion fuel was found to be in the range approximately from 2 to 200 nm in both procedures. The engine test bed was utilized to combust the emulsion ...

In Malaysia, abundant agricultural wastes are generated yearly. Therefore it is beneficial to discover new ways to utilize the wastes and employ the carbon source in different industries. Biochar are produced through many heat treatments such as combustion, gasification and pyrolysis for energy generation. The characteristics of these stable carbons such as the physical properties, chemical composition, surface area and surface chemistry determine the effectiveness of the cabon in different applications. Biochar has the ability to retain carbon and this condition is advantageous to prevent the release of carbon back to the atmosphere in the form of carbon dioxide. Application of biochar to soil helps to improve soil fertility and raise agricultural productivity. Biochar also has the ability to reduce carbon dioxide in the flue gas system. There have only been a few studies that discuss on the potential applications of this agriculture waste. The biochar's potential application as carbon sequester for soil application, energy production and dye sorption is being explored in this paper.

In Malaysia, abundant agricultural wastes are generated yearly. Therefore it is beneficial to discover new ways to utilize the wastes and employ the carbon source in different industries. Biochar are produced through many heat treatments such as combustion, gasification and pyrolysis for energy generation. The characteristics of these stable carbons such as the physical properties, chemical composition, surface area and surface chemistry determine the effectiveness of the cabon in different applications. Biochar has the ability to retain carbon and this condition is advantageous to prevent the release of carbon back to the atmosphere in the form of carbon dioxide. Application of biochar to soil helps to improve soil fertility and raise agricultural productivity. Biochar also has the ability to reduce carbon dioxide in the flue gas system. There have only been a few studies that discuss on the potential applications of this agriculture waste. The biochar's potential application as carbon sequester for soil application, energy production and dye sorption is being explored in this paper.

Recently, hydrogen production from biomass has become an attractive technology for power generation. The main objective pursued in this work is to investigate the hydrogen production potential from agricultural wastes (coconut coir and palm kernel shell) by applying the air gasification technique. An experimental study was conducted using a bench-scale fluidized bed gasifier with 60 mm diameter and 425 mm height. During the experiments, the fuel properties and the effects of operating parameters such as gasification temperatures (700 to 900°C), fluidization ratio (2 to 3.33 m/s), static bed height (10 to 30 mm) and equivalence ratio (0.16 to 0.46) were studied. It was concluded that substantial amounts of hydrogen gas (up to 67 mol%) could be produced utilizing agricultural residues such as coconut and palm kernel shell by applying this fluidization technique. For both samples, the rise of temperature till 900°C favored further hydrocarbon reactions and allowed an increase of almost 67 mol% in the release of hydrogen. However, other parameters such as fluidizing velocity and feed load showed only minor effects on hydrogen yield. In conclusion, agricultural waste can be assumed as an alternative renewable energy source to the fossil fuels, and the environmental pollution originating from the disposal of agricultural residues can be partially reduced.