Opportunities and challenges for biodiesel fuel

Biodiesel, which is a new, renewable and biological origin alternative diesel fuel, has been receiving more attention all over the world due to the energy needs and environmental consciousness Biodiesel is usually produced from food-grade vegetable oils using transesterification process Using food-grade vegetable oils is not economically feasible since they are more expensive than diesel fuel Therefore, it is said that the main obstacle for commercialization of biodiesel is its high cost Waste cooking oils, restaurant greases, soapstocks and animal fats are potential feedstocks for biodiesel production to lower the cost of biodiesel However, to produce fuel-grade biodiesel, the characteristics of feedstock are very important during the initial research and production stage since the fuel properties mainly depend on the feedstock properties This review paper presents both biodiesel productions from various feedstocks and their effects on the fuel properties

Biodiesel production from various feedstocks and their effects on the fuel properties.

This paper analyzes the performance and emissions of biodiesel from different feedstocks. The main goal of this paper is to provide information to the engineers, industrialists and researchers who are interested on biodiesel and to emphasise biodiesel as a promising alternative replacement for fossil fuels. A substantial number of literatures from highly rated journals in scientific indexes were cited preferentially since 2000. The performance and emissions indicators such as brake torque, brake power, BTE, EGT, BSFC NOx, PM, CO, CO2, HC and smoke density have been evaluated in comparison to pure diesel. The results showed that different sources of biodiesel feedstocks give different results to engine performance and emissions. Surprisingly some of the research yielded favourable results towards the biodiesel as compared to pure diesel. The study concluded that biodiesel can be used in compression ignition engine as a replacement of diesel fuel to fulfil the global energy demand. However, further research on about optimisation, cost-effectiveness and availability of biodiesel needs to be carried out to help ensure that biofuel will be able to fully replace fossil fuel.

Effects of biodiesel from different feedstocks on engine performance and emissions: A review

Methods and systems are provided for mitigating engine pre-ignition based on a feed-forward likelihood of pre-ignition and feedback from a pre-ignition event. In response to an indication of pre-ignition, a cylinder may be enriched while an engine load is limited. The enrichment may be followed by an enleanment to restore exhaust catalyst feed-gas oxygen levels. The mitigating steps may be adjusted based on engine operating conditions, a pre-ignition count, as well as the nature of the pre-ignition.

Method and system for pre-ignition control

Transportation and shipping activities are major contributor to air pollution at sea where most of it occurs as a result of exhaust emissions from ships. Stringent emission limitations enforced by the International Maritime Organization have hastened the need to find a new alternative fuel for marine diesel engines. Thus, biodiesel fuel was chosen as one of the environmentally friendly alternative energy that can reduce ship toxic gas emissions and at the same time reduces dependence on petroleum-based fuels. Therefore, the purpose of this paper is to provide a comprehensive review of biodiesel as an alternative fuel for marine diesel engine applications. This review covers the biodiesel fuel background, engine performance, history, recent progress, engine warranty, issues, challenges, and possible solutions on using biodiesel for marine applications. A significant number of literatures from indexed journals were cited accordingly. The results of previous studies had shown that the use of biodiesel would mostly increase the amount of brake specific fuel consumption and nitrogen oxide gas while conversely reducing other toxic gas emissions. Although a number of issues and challenges arise, most marine engine manufacturers give conditional warranty against the use of biodiesel in the engines. The study concluded that biodiesel and its blends have a bright future in the marine sector, provided some of the highlighted issues can be solved.

Biodiesel as alternative fuel for marine diesel engine applications: a review.

Fuel properties play a dominant role in the spray, mixture formation and combustion process, and are a key to emission control and efficiency optimization. This paper deals with the influence of the fuel properties on the spray and combustion characteristics in a high-pressure and temperature chamber. Light diesel fuel spray and combustion images were taken by using a high-speed video camera and analyzed by their penetration and evaporation characteristics in comparison with current diesel fuel. Then, a single-cylinder DI engine was used to investigate combustion and exhaust characteristics. The mixture formation of the light diesel fuel is faster than that of the current fuel depending on physical properties like boiling point, density, viscosity and surface tension. Engine test results show that smoke is reduced without an increase in other emissions.

Effects of diesel fuel characteristics on spray and combustion in a diesel engine

An exhaust emission control apparatus for an internal combustion engine includes a fuel injection valve placed substantially at a midpoint above a combustion chamber of the engine; a piston having an outer cavity formed substantially in a midsection of an upper surface of the piston and an inner cavity formed in a bottom surface of the outer cavity; an ignition plug placed in a region right above the outer cavity; an exhaust purifying catalyst provided in an exhaust passage of the engine; and a controller. This controller is configured to carry out a stratified charge combustion when a temperature rise for the exhaust purifying catalyst is required, by forming air-fuel mixture which is richer than stoichiometric ratio and is able to be ignited by the ignition plug, within the outer cavity and in an area substantially right above the outer cavity, from a fuel injected through the fuel injection valve.

Exhaust emission control apparatus and method for internal combustion engine

A control apparatus is provided for a four stroke cylinder direct-injection internal combustion engine having a cylinder and a piston disposed within the cylinder. The control apparatus includes a variable compression ratio mechanism for variably controlling the engine compression ratio by changing the top dead center position of the piston and a fuel injection device for injecting fuel directly into the cylinder. When the actual compression ratio of the engine is higher than a target compression ratio, the variable compression ratio mechanism reduces the compression ratio, and in accordance with the reduction in the compression ratio, the fuel injecting device injects an intake fuel injection amount in the intake stroke and a compression fuel injection amount in the compression stroke, and the timing for starting the fuel injection in the compression stroke is retarded.

Control apparatus for a cylinder direct-injection internal combustion engine

PROBLEM TO BE SOLVED: To prevent an ignition plug from being fouled by avoiding the concentration of spray stirred up from the surface of a crown near the ignition plug in a cylinder injection internal combustion engine in which a fuel injection valve is disposed to face the surface of the crown of a piston. SOLUTION: The penetration provided to the spray by the fuel injection valve 21 is differentiated between one side of the ignition plug 22 with respect to an injection center axis n and the other side thereof on the opposite side. At one side of the ignition plug 22, the penetration of the sprays s1, f1 is lowered more than at the other side. Ignition is performed for the spray s1 sprayed by the fuel injection valve 21 before it is collided with the surface of the crown of the piston 12. COPYRIGHT: (C)2007,JPO&INPIT

Cylinder injection internal combustion engine

PROBLEM TO BE SOLVED: To provide an air conditioning indoor unit capable of easily and rapidly acquiring the contaminated state of a drain pan without removing the drain pan from a case body to accurately determine a cleaning time of the drain pan, and preventing drain collected in the drain pan from dropping below the air conditioning indoor unit to contaminate a floor surface or a desk surface existing below the air conditioning indoor unit. SOLUTION: The air conditioning indoor unit 10 includes an indoor heat exchanger 12, the drain pan 13, a blower driving motor, a blower 14, and an air guide plate 15 which are provided in the case body 11 embedded and set in a ceiling. The drain pan includes a through-hole 13b extending through the drain pan 13 in the plate thickness direction, and a transparent member 19 is fitted to the through-hole 13b. COPYRIGHT: (C)2009,JPO&INPIT

Daisuke Tanaka

Papers

Effects of diesel fuel characteristics on spray and combustion in a diesel engine

Exhaust emission control apparatus and method for internal combustion engine

Control apparatus for a cylinder direct-injection internal combustion engine

Cylinder injection internal combustion engine

Air conditioning indoor unit