Energizing tomorrow: unleashing spirulina's potential in engine performance optimization and emission reduction.

Area of Science:

• Renewable Energy Engineering
• Combustion Science
• Environmental Science

Background:

• Growing concerns over fossil fuel depletion and climate change necessitate sustainable energy alternatives.
• Biofuels derived from biomass, particularly microalgae, offer a promising renewable energy source for enhanced energy security and environmental safety.
• Optimizing the performance and emission characteristics of internal combustion engines using microalgae biodiesel blends is crucial for their practical application.

Purpose of the Study:

• To evaluate the performance attributes and emission characteristics of a CI (Compression Ignition) engine fueled with a spirulina microalgae biodiesel blend (20% algae biodiesel, 80% diesel).
• To investigate the effects of varying engine load and injection timing on the engine's brake thermal efficiency and emission profile.
• To optimize the operating parameters for the algae biodiesel blend using response surface methodology (RSM) for improved performance and reduced emissions.

Main Methods:

• Experimental testing of a CI engine using a 20% spirulina microalgae biodiesel and 80% diesel blend across various engine loads (20-100%) and injection timings (20°, 23°, 25°, 28° bTDC).
• Measurement of key performance indicators, including brake thermal efficiency.
• Analysis of emission characteristics, specifically carbon monoxide (CO), hydrocarbon (HC), and oxides of nitrogen (NOx) levels.
• Application of response surface methodology (RSM) for optimizing engine operating parameters.

Main Results:

• The peak brake thermal efficiency at 100% engine load varied with injection timing, with the highest efficiency of 26.79% observed at 20° bTDC for the biodiesel blend, compared to 27.76% for diesel.
• Significant reductions in CO (average drop of 53.46%) and HC (average fall of 42.32%) emissions were observed at 20° bTDC injection timing for the biodiesel blend compared to diesel.
• An increase in NOx emissions was noted (8.06% at 20° bTDC), while RSM optimization identified 85.19% engine load and 20° bTDC injection timing as optimal, yielding 25.44% brake thermal efficiency and reduced emissions.

Conclusions:

• The spirulina microalgae biodiesel blend demonstrates potential as a viable alternative fuel in CI engines, offering reduced CO and HC emissions.
• Injection timing significantly impacts engine performance and emissions, with 20° bTDC showing the most favorable results for emission reduction.
• Optimized operating conditions using RSM enhance the fuel's efficiency and environmental benefits, paving the way for sustainable diesel engine operation.