Use of hydrous ABE-glycerin-diesel microemulsions in a nonroad diesel engine - Performance and unignorable emissions

Mitigating exhaust emissions in CI engines using butanol-diesel-water microemulsions

The current research work examines the usability of surfactant-free microemulsion fuels as a substitute in CI engines, with alcohol being used as an amphi-solvent. Studies were carried out on different compositions of microemulsions with 35% volume and 40% volume butanol, named ME35 and ME40, having 57.8-64.4% volume diesel and 0.6-2.2% volume water. Most of the microemulsions had properties such as viscosity, specific gravity, cloud point, and sulfur content comparable to those of diesel. The heating values and cetane indices of the microemulsions were 0.09-8.7% and 19.4-28.7% lower than diesel due to the addition of water and alcohol. The water and sediments percentages were found to be low, even after the addition of water, indicating the microemulsions were stable. ME40 showed an average of 0.6-3.5% improvement in BTE, but the BSFC was also increased by 5.3-8.9%. The emissions of HC, NO_x, and PM showed an average decrease of 19.0-48.9%, 14.8-41.9%, and 10.06-50.24%, respectively, for all the microemulsions at all the loads. The CO emissions were lower at higher loads and vice versa, but the average CO emissions showed 5.16-31.9% decrease due to significant reductions at higher loads. It could, therefore, be concluded that microemulsions are a promising sustainable and cleaner substitute for diesel. Synopsis Microemulsion fuels successfully replaced up to 42% of diesel, with significant reduction in emissions of CO, HC, NO_x, and PM.

Improvement of the combustion, emission, and stability features of diesel-methanol blends using n-decanol as cosolvent

This research endeavored to boost the applicability of methanol in CI engines utilizing n-decanol as cosolvents. The work was split into binary phases. Firstly, the stabilities of pure methanol (M100) and hydrous-methanol (MH10), with diesel as a reference fuel, were examined applying various temperatures: 10 °C, 20 °C, and 30 °C. The findings showed that the M100-diesel and MH10-diesel combinations were unstable. Thus, n-decanol was utilized as a cosolvent. Following by the engine combustion and emissions characteristics were evaluated by manipulating three proportions of M100-diesel mixtures with n-decanol. Three mixtures comprised of 5, 10, and 15% M100 with 20% n-decanol, which are denoted as M5, M10, and M15, correspondingly. These combinations were assessed via thermogravimetric assessment, and their physicochemical properties were assessed corresponding to the ASTM. The maximum in-cylinder pressure, heat release rate, and pressure rise rate diminished by 10, 11, and 10%, respectively, for the M100/diesel/n-decanol combinations compared with the diesel oil. The brake thermal efficiency lowered by 10%, whereas the brake specific fuel consumption enlarged by 10% for the combinations compared with the diesel. NO_x and smoke opacity levels diminished by about 30 and 50%, respectively, whereas the CO and UHC enlarged by about 50 and 60% for the blends compared with the diesel oil.