Smoke and NOX emissions of combustion engine using biofuels

M. Pexa¹*, J. Čedík¹ and R. Pražan²

¹Czech University of Life Sciences, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamycka 129, CZ 16521 Prague 6, Czech Republic
²Research Institute of Agricultural Engineering, p.r.i., Drnovská 507, CZ 16101 Prague 6, Czech Republic
*Correspondence: pexa@tf.czu.cz

Abstract:

Production of solid particles significantly increases the dangerousness of combustion engines. The excellent sorbtion characteristics of the solid particles increases their harmful effects and makes them very dangerous component of emissions which causes health problems. Currently there are many design solutions which aim to reduce smoke of combustion engines. One of the most significant solutions suggests increasing the injection pressures up to the limit of 250 MPa and filtering the exhaust gases. The paper compares different fuels and biofuels, whether used alone or in mixtures, and their effect on smoke of supercharged CI engine. The comparison uses the 8-point NRSC (Non-Road Steady Cycle) test during which the following fuels were used: diesel, rapeseed methyl ester, rapeseed oil, Jatropha curcas oil, biobutanol, hydrotreated oil and other blended fuels. The measurement and comparison results show that using biofuels can significantly reduce smoke of combustion engine by up to tens of percent in comparison to diesel.

Key words:

Impact of immature willows stems chopping quality on the harmful emissions evaluation

A. Jasinskas, I. Ulozevičiūtė, E. Šarauskis and A. Sakalauskas

Aleksandras Stulginskis University, Faculty of Agricultural Engineering, KaunasAkademija,
Studentu str. 15A, LT-53361 Kauno r., Lithuania;

Abstract:

The analytical review of the experimental research results of energy plants preparation, burning efficiency and the emissions of harmful substances into the air while burning these plants, is presented in this paper. After the experimental study, immature (1–2 year of growth) willow (Salix viminalis) stems chaff chopping quality were observed. In truth, use of the drum chopping equipment prepared chaff fractional composition, and there were defined and calculated immature willow stems chaff of theoretical length (from 11.8 till 61.3 mm). They were presented and compared with the experimental research results of the low power boiler efficiency and harmful emissions into the air while burning energy plants – immature willow, chopped by the drum chopper of Maral-125 combine. The test was carried out in the laboratory of the low power boiler, which is designed to burn wood, wood briquettes and large wood chaff. After determination of boiler efficiency and harmful substances (CO₂, CO, NO, NO_x) emissions into the environment while burning different lengths of willow chaff, it was concluded that the boiler developed about 66–86% of nominal boiler power, and pollution emissions concentration into the environment was lower when willow chaff of 49.2 mm length was burned.

Key words:

boiler power, burning, chaff, chopping quality, harmful emissions, immature willows, pollution, stems