Impact of using Iraqi biofuel–kerosene blends on coarse and fine particulate matter emitted from compression ignition engines

Nano and fine particles have caused serious health problems. Despite the continuous decline of their concentrations, the remaining amounts are still considered a problem in compression ignition engines. This study describes the impact of using biokerosene fuel instead of Iraqi diesel, which is characterised by high sulphur content, on the concentrations of various particulate matter (PM) sizes emitted from engines.A TD 313 Fiat diesel rig (a 4-stroke, 4-cylinder, water-cooled and direct injection engine) was used in the experimental tests. In addition to biofuel (produced from sunflower vegetable oil through a transformation process), Iraqi diesel and kerosene were also used. Four blends were produced, namely, diesel mixed with 10% and 20% volume fractions of biodiesel (denoted as BD 10 and BD 20, respectively) and kerosene added with 10% and 20% biofuel (labelled as KB10 and KB20, respectively).Fuelling the engine with biokerosene significantly reduced PM1.0 by up to 12.3%, 36.65%, 60.92% and 81% and PM2.5 by up to 21.29%, 25%, 41.43% and 51.85% for BD10, BD20, KD10 and KD20, respectively, compared with diesel at varying engine speed. Changing engine load at a constant speed reduced PM10 by up to 12.9%, 21%, 31.6% and 42.7% and total suspended particles by up to 5%, 12%, 21.5% and 25.5% for BD10, BD20, KD10 and KD20, respectively, compared with diesel.The concentrations of all PM sizes were reduced when engine was running at medium speed and load. By contrast, concentrations increased when engine was running at low and high loads and speeds. Results demonstrated that biokerosene is better than biodiesel–diesel blends in reducing PM emissions.