A comprehensive review of water injection and emulsion technology for biodiesel-fuelled CI engine

ABSTRACT

Biodiesels are mandatory due to the depletion of petroleum fuels and it also gives a relatively better performance and emissions except for NO_x emission. The biodiesel-fuelled compression ignition (CI) engine reduces emissions of hydrocarbon (HC), carbon monoxide (CO) significantly. However, it increases the nitrogen oxides (NO_x) emissions. It is the main concern in a diesel engine to meet stringent emission standards. The water injection (WI) and emulsification methods are considered as one of the cost-effective methods to reduce NO_x emissions in CI engine. The emission characteristics of the diverse biodiesel–diesel blends have been summarised and discussed. NO_x emissions can be reduced up to 37–50% by WI method in biodiesel engines. It is also observed that water–biodiesel emulsification reduces the NO_x about 10–60% compared to conventional diesel. However, these technologies (WI and emulsification) reduce NO_x and particulate matter emissions considerably but increases HC, CO emissions and increase specific fuel consumption.

KEYWORDS:

• Biodiesel
• CI engine
• NO_x emission
• water injection
• emulsification

Disclosure statement

No potential conflict of interest was reported by the authors.