Exhaust emissions of non-road mobile machine: Real-world and laboratory studies with diesel and HVO fuels

Abstract

Exhaust emissions emitted by a non-road mobile machine were studied chasing a tractor in real-world conditions and repeating the same transient tests with a similar engine on an engine dynamometer where additionally, nonroad steady state tests were carried out. The engines were equipped with an oxidation catalyst (DOC) and a selective catalytic reduction (SCR) system, and they were fuelled by fossil diesel fuel with ultra-low sulphur content and hydrotreated vegetable oil (HVO). By substituting diesel fuel with HVO the on-road emissions of nitrogen oxides (NOx) reduced 20% and particle number 44%, the emission factors being EFNOx=1.62±0.04 g/kWh and EFN=(28.2±7.8)x10 13 #/kWh. Similar trend was observed for NOx at laboratory although the emissions were somewhat smaller than on-road. In contrast to real-world, in the laboratory experiment the EFN was only 2% smaller with HVO than with diesel, and these emission factors were almost one order of magnitude smaller than observed on-road. The number size distribution and volatility measurements showed that in real-world experiments small nucleation mode particles were formed during uphill and during downhill in engine braking conditions. These were not observed at laboratory. However, nucleation mode particles were observed in the laboratory experiments at high load steady driving conditions. At steady state tests the emissions strongly depended on engine load and engine speed with both fuels.

Characterization of the emissions impacts of hybrid excavators with a portable emissions measurement system (PEMS)-based methodology

“…Environmental Protection Agency (EPA)'s recent emissions inventory data, off-road diesel equipment is estimated to be the third largest source for nitrogen oxides (NO x ) emissions and second largest source for particulate matter (PM) emissions, representing 14.5% and 24.3%, respectively, of total NO x and PM emissions from mobile sources (US EPA, 2013). A European study found that non-road machines made up about 31% and 42%, respectively, of total annual NO x and PM emissions from diesel power vehicles in Finland in 2014 (Pirjola et al, 2017). Wang et al (2016) found that in China off-road equipment emitted more PM 2.5 than all of the on-highway vehicles combined, and suggested that real world emissions and activity data for off-road equipment is "desperately needed".…”

Estimation of Gas and Dust Emissions in Construction Sites of a Motorway Project

“…Tunnels and bridge are the components of a road with the greatest impact in terms of air emissions.Sustainability 2019, 11, 7218 2 of 14 mobile fonts. The adverse health and environmental effects of PM and trace gases have been confirmed by several studies [10][11][12].Numerous studies have focused on off-road equipment emissions inventories [5,7,8,[13][14][15]; however, the available data for comprehensive evaluations are still considerably more limited compared to the on-road mobiles sources. Few developed countries have published greenhouse gases (GHG) and non-GHG emission factor standards for non-road equipment.…”

“…A noteworthy amount of PM 10 , often higher than that produced by other construction operations [21,22] are also released by the movement of the vehicles on dirty or unpaved and temporary roads in the worksites [23][24][25].In the literature, few studies deal with the real-world emissions from construction sites or with extensive evaluation on the emissions produced during the whole period of construction [26]. Some studies focused on data of exhaust emissions of the construction machineries [1,5,7,8]. Others investigated the influence of construction site emissions on local air quality [4,27,28] or calculated emission factors to assess emission inventories for all construction activities [21].Comprehensive studies that take into account all these objectives, and that consider various construction activities and processes and their duration, are scarce [1,6,29].…”

“…Numerous studies have focused on off-road equipment emissions inventories [5,7,8,[13][14][15]; however, the available data for comprehensive evaluations are still considerably more limited compared to the on-road mobiles sources. Few developed countries have published greenhouse gases (GHG) and non-GHG emission factor standards for non-road equipment.…”

“…In the literature, few studies deal with the real-world emissions from construction sites or with extensive evaluation on the emissions produced during the whole period of construction [26]. Some studies focused on data of exhaust emissions of the construction machineries [1,5,7,8]. Others investigated the influence of construction site emissions on local air quality [4,27,28] or calculated emission factors to assess emission inventories for all construction activities [21].…”