NOx Emission Factors Research Articles

Standard environmental evaluation framework reveals environmental benefits of green light optimized speed advisory: A case study on plug-in hybrid electric vehicles

Green Light Optimized Speed Advisory (GLOSA) is a cutting-edge technology for intelligent transportation and is being increasingly applied on the ground worldwide. However, evaluating the environmental benefits of vehicles using GLOSA has become a challenge owing to the complexity and unpredictability of real-traffic. Here, a standardized environmental benefit evaluation framework for GLOSA is first proposed, which combined standard driving cycle (DC) database and high-precision emission models. The DC database was constructed using Markov chain approach. The database has certain randomness and diversity while considering the real driving characteristics. The plug-in hybrid electric vehicle (PHEV) CO2 and NOx emission models were constructed based on machine learning approach. These models have good generalization ability and prediction accuracy, with 0.87 and 0.80 R2 on the test set, respectively. In the constructed model, vehicle specific power (VSP) and state of charge (SOC) were identified as the most significant features affecting CO2 and NOx emissions. According to the evaluation results, the use of GLOSA reduces the emission factors of CO2 and NOx by 16.3% and 18.4%, respectively, when the initial SOC of PHEV is 20%. When the initial SOC is 50%, the emission factors of CO2 and NOx of the PHEV with GLOSA are reduced by 22.1% and 26.6%, respectively. The generality of this framework solves the different evaluation scales problem due to the randomness traffic. The framework serves the construction of intelligent and clean transportation while also assisting in the promotion, optimization, and recognition of GLOSA's limits.

Analysis of Exhaust Pollutants from Four-Stroke Marine Diesel Engines Based on Bench Tests

Implementation of new emissions regulations calls for a reassessment of the emissions levels of newly built ships sailing in Chinese regions. In this paper, marine diesel engines are subjected to emissions bench tests using high-precision testing equipment. A total of 135 marine diesel engines meeting the Limits and Measurement Methods for Exhaust Pollutants from Marine Engines (CHINA I/II) were first systematically analyzed. The emission factors of marine main engines (ME) and auxiliary engines (AE) were obtained under different displacements. The results show that the fuel-based emission factors for NOX + HC and CO meeting CHINA I/II are 25.80~44.87/16.47~46.35 and 2.47~13.22/1.64~5.62 kg/t-fuel, respectively. The energy-based emission factors for NOX + HC, CO, CO2, and PM satisfying CHINA I/II are 5.70~9.24/3.70~9.07, 0.49~2.30/0.36~0.99, 620~683/612~718, and 0.05~0.36/0.05~0.27 g/kWh, respectively. Additionally, the specific emission of NOx rises with the increase in single-cylinder displacement, so the CO emission limit of pure diesel fuel is recommended to be lower than 5 g/kWh. The results in this paper provide valuable basic data for research on and estimation of ship emissions in waterway transportation and for understanding the emission characteristics of marine diesel engines.

DETERMINATION OF NOX EMISSION FACTOR FOR DIESEL ENGINES OF RECREATIONAL BOATS BY ON-BOARD MEASUREMENT

In this study, NOx emissions from diesel engines of 75 recreational boats were measured on-board in accordance with the simplified method specified in the NOx Technical Code. The study was carried out in boats with ranging between 14.42 m-37.50 m in length and engines power varying between 138 kW–2,040 kW. NOx emissions were measured by using a portable exhaust gas analyser (Testo 350 Marine) in ppm in a dry basis. An in-house program was developed to calculate the final emission results in g/kWh. The main aim of the study is to develop NOx emission factors for recreational boats, which are not specifically included in previous emission factor studies. The NOx emissions of the marine diesel engines of the recreational boats were found in range of 0.92 g/kWh – 10.69 g/kWh while the mean emission factor was found as 4.81 g/kWh.

Impact on air quality from increasing cruise ship activity in Copenhagen port

The impact of the growing cruise ship industry on air quality levels was investigated at the port of Copenhagen, Denmark. In 2018, 345 cruise ships visited Copenhagen, emitting 291 tons of NOx near the city centre. A spatiotemporal cruise ship emission inventory was developed for 2018 based on port list information, engine data, main and auxiliary engine power functions, and NOx emission factors, and was implemented in the OML-Multi atmospheric dispersion model. Evident plume effects from the cruise ships, which were traced by introducing the concept of likely concentration contribution, were obtained in the modelled and measured concentrations at Langelinie Quay, which is the busiest cruise ship terminal in Copenhagen port. Hourly peak values of NOx well above 200 μg m−3 were obtained at the top of a residential building at Langelinie Quay. The emissions from cruise ships were increasing the annual concentration of NO2 in the port area by up to 31% at ground level, and 86% 50 m above the ground in comparison to the urban background level. No exceedance of the European annual limit value of NO2 was obtained. The short-term impact of cruise ships was more pronounced with local exceedances of the hourly European limit value for NO2. Increasing cruise ship activity in Copenhagen port leads to air quality deterioration on short time scales with implications for human health.

Comparative Analysis of Emission Characteristics of In-Use China II–V Gasoline, Hybrid, Diesel-Fueled Vehicles

Increasingly stringent regulations regarding vehicle emissions have contributed to the diversification of vehicle technologies, resulting in the increasing complexity of typical vehicles that make up a fleet. In order to investigate the real gas emissions of different typical vehicles, tests were conducted using a portable emission measurement system (PEMS) in Beijing and emission studies were conducted on eight light-duty passenger vehicles (LDPVs, including light-duty gasoline passenger vehicles and hybrid electric vehicles), eight heavy-duty passenger vehicles (HDPVs), and four light-duty trucks (LDTs). The results show that the emissions of relevant pollutants from LDPV meet the emission standard limits. The emission factors of CO2, CO, NOX, and HC of China IV and China V hybrid electric vehicles (HEVs) are much smaller than the emission standard limits and the emission factors of other vehicles, which have better emission reduction effects. Among LDPV, heavy-duty passenger vehicles (HDPVs), and LDT, the emissions of HDPV and LDT are extremely high. Emission characteristics vary on different types of roads, with the highest emission factors generally occurring on secondary roads. The micro-trip method was used to explore the influence of speed on emission factors. HEV are less sensitive to speed changes and can still maintain a low emission level at low speeds. The average speed and emission factors of HDPV in micro-trip has a strong correlation.

NH3 and N2O emission durability of the heavy-duty diesel engine with DOC, DPF, SCR, and ASC through the accelerated aging method

A general accelerated aging method for aftertreatment devices of Heavy-duty Diesel Engine (HDDE) is proposed in this paper, and three sets of aftertreatment devices were aged according to this method. The error between the World Harmonized Transient Cycle (WHTC)-NOx emission factors of conventional aging and those of accelerated aging fitted by equivalent thermal accumulation is −4.12 to 3.13 %, which proves that the two methods have good equivalence. Meanwhile, the NH3 and N2O emission characteristics and durability were tested by Fourier Transform Infra-Red Spectroscopy (FTIR) equipment. The results show that NH3 and N2O emissions do not deteriorate linearly with the intensification of thermal aging like NOx. Except that the NH3 emission of AT03 exceeds the limit of China VI emission regulation (the average and maximum NH3 concentration in the WHTC test are 35.25 ppm and 350.30 ppm, separately), NH3 emission of other aged devices meet the requirements. Combined with the equivalent durability mileage of 1130000 km of AT02, the test China VI HDDE can effectively control NH3 emissions and has a large margin with the limit requirements. However, the deterioration rate of N2O emission gradually slows down with the intensification of accelerated aging. The accelerated aging tests also indicate that N2O generation is closely related to NH3 in SCR, consistent with previous studies conclusions of low-temperature and high-temperature N2O generation mechanisms. Equally important is that the N2O emission emitted from test China VI HDDE is significantly higher than the emission limit of the Environmental Protection Agency (EPA). The N2O emission factors under the WHTC test are as high as 0.15 to 0.35 g/kWh, which should draw the attention of Chinese environmental regulatory authorities, who should start to formulate N2O emission limits and put forward complementary strategies to reduce N2O emissions from HDDEs.

How accelerating the electrification of the van sector in Great Britain can deliver faster CO2 and NOx reductions

As a major emission contributor with significant growth potential, the light goods vehicles (vans) play an important part in achieving net-zero. In 2020 the UK government committed to phasing out sales of new internal combustion engine (ICE) vans by 2030, but the impact of the policy and how far are we to decarbonize the entire van fleet by 2050 is unclear. This paper investigates the CO2 and NOx emission trends in the van sector in Great Britain under the 2030 ICE phase-out. ECCo model11http://www.element-energy.co.uk/sectors/low-carbon-transport/project-case-studies/ is used to forecast the future van population by powertrain. The annual van mileage is estimated based on the van activity survey22https://www.gov.uk/government/statistics/van-statistics-2019-to-2020. The instantaneous emission model PHEM, NAEI emissions inventory and remote sensing measurements are used to parameterize real-world driving emission factors of CO2 and NOx. Scenarios have been set out to assess the impact of enablers and barriers affecting the pace of emission reductions. Results suggest vans are on track to reach the tailpipe net-zero target by 2050 under all scenarios, and the speed of NOx reduction is even faster. A rapid transition to battery electric vans in the early to mid-2020s will significantly lower CO2, with associated estimated monetary benefits of £1.3 billion.

Study on the real-world emission characteristics of gaseous and particulate pollutants from an inland ship using a portable emission measurement system.

The emissions of pollutants from inland ships endanger the urban environment and human health, deserving quantitative study to make reduction measurements to achieve clean emissions. In this study, the real-world gaseous emissions (CO, THC, SO2, NOx) and particulate emissions including particle mass (PM) and particle number (PN) as well as the particle size distribution and particle compositions from an inland ship were investigated using a portable emission measurement system (PEMS) method. The results showed that the emission concentrations of CO, THC, PM and PN at departure and idling conditions were significantly higher than those at other conditions, while the emission concentrations of NOx and SO2 at cruising condition were the highest. The particle size distribution always presented a bimodal distribution ranged at 40nm and 200nm respectively at different conditions and engine loads. The proportion of nucleation mode particles was the highest at departure condition, and a larger engine load resulted in a declined proportion of nucleation mode particles. The anions of the emitted particles mainly included nitrite ion (NO2-), nitrate ion (NO3-), sulfate ion (SO42-), and cations mainly included ammonium ion (NH4+), sodium ion (Na+) and potassium ion (K+). The main components of organic carbon (OC) in soot were OC1 and OC2, accounting for more than 80%, while the main component of elemental carbon (EC) was EC2, accounting for 83.9%. The emission factors based on fuel consumption of CO and THC were significantly higher at idling conditions than other conditions, and the emission factor of NOx was higher at cruising conditions, while the emission factors of PM and PN were higher at departure and idling conditions than other conditions.

Characterizing carbon emissions from China V and China VI gasoline vehicles based on portable emission measurement systems

On-road vehicle has been a prominent emission source, hence a key target of control for environment, health, and climate concerns. While considerable efforts have been made to investigate criteria pollutants such as adverse gaseous and particulate emissions across the world, there is limited systematic research to characterize on-road carbon emissions, especially as countries strive to set and achieve various climate goals (i.e., carbon neutrality, carbon peaking by a certain year, etc.) through cleaner vehicle technologies such as the latest vehicle emission standard, China VI (2020). This study used the portable emission measurement system (PEMS) to reveal the real-world emissions from two light-duty gasoline vehicles, one meeting the China V standard and the other China VI. The PEMS measurements were performed secondly in urban and suburban areas respectively, and finally yielded 10 h of rich and finely resolved emissions data. In addition of single-factor analysis, this study employed two machine learning models, stepwise regression and light gradient boosting machine (LightGBM), to investigate the coupling effects among vehicle/traffic parameters and identify driving behavior, engine condition, and external environment as key determining factors that affect vehicular carbon emissions. In particular, engine load percent and engine speed were confirmed to be the most dominant factors affecting vehicular carbon emissions under both China V and China VI standards, explaining ∼60% of variability in carbon emissions. As a result, vehicle specific power (VSP) is derived from vehicle travel parameters and used as a surrogate for carbon emission estimation. The external facility and environmental factors turned out significant as well in affecting vehicle carbon emissions: carbon emissions from the same vehicle were significantly higher in an urban setting then in suburban areas, mostly due to the more aggressive driving patterns in congested urban traffic. Travelling under relatively better traffic conditions on expressways gave the lowest per-distance emission factors of CO2, CO, and NOx. Comparing between the China V and VI vehicle, our PEMS data show significant carbon emission reduction benefits (15.9% in CO2, 28.8% in CO) as we move to the new China VI standard, although such benefit was not observed in NOx emissions.

Synergetic removal characteristics of mercury for ultra-low emission coal-fired power plant

The synergetic mercury removal by flue gas treatment process in coal-fired power plants is widely accepted, but there is a lack of a corresponding model to describe mercury transformations. In this work, a model for mercury transformations is established in a flue gas treatment process model using Aspen Plus. The concentrations, mass flow rates, and normalized emission factors of mercury, NOX, particulate matters (PM), and SO2 are investigated in a 660 MW coal-fired power plant. The mercury oxidation efficiency of the selective catalytic reduction (SCR) unit is 56.9 %. The mercury removal efficiency of the electrostatic precipitator (ESP) and wet flue gas desulphurization (WFGD) units are 53.5 % and 34.4 %, respectively. The ultra-low emission system achieves 63.3 % removal of mercury. Approximately 53.5 % of mercury is retained in the fly ash. The emission factor of mercury is 0.0131 mg/kWh and increases to 0.0265 mg/kWh when the load decreases from 100 % to 50 %. The emission factors of PM, SO2 and NOX are 7.1, 97.1, and 142.9 mg/kWh at full load, and 10.9, 97.4, 150.0 mg/kWh at 50 % load, respectively. The proposed flue gas treatment process model is considered a feasible approach for quantitative evaluation of multi-pollutants emissions at plant level.

Analysis of spatial-temporal atmospheric emissions from heavy-duty diesel trucks in central and southern Liaoning urban agglomeration

The problem of diesel vehicle pollution has aroused wide concern in central and southern Liaoning Urban Agglomeration (CSLA), as it is associated with large amounts of atmospheric emissions. This article focuses on heavy-duty diesel trucks (HDT) of Chinese National Standards for heavy-duty diesel trucks (GB) III, GB IV, and GB V. This research measures emission factors (EF) of NOx, CO, and PM by vehicle tests. Subsequently, the emission inventory has been established according to emission factors (EF), activity levels (AL), and Technic guidelines for road motor vehicle emission inventory of air pollutants (Guideline, 2015) in central and southern Liaoning Urban Agglomeration (CSLA). This study further obtained the spatial distribution map of pollutants in CSLA, 2019, using the Geographic Information System (GIS). Results exhibit NOx and CO emissions of HDT directly proportional to the amount of their ownership, and GB III was the main contributor to the PM emissions accounting for nearly 74%. It was concluded the annual emissions of NOx, CO, and PM in CSLA were 20.34, 6.46, and 0.044 million tons individually in 2019. Moreover, the emissions of NOx and CO in heating seasons were higher than in non-heating seasons, accounting for approximately 56% and 57% of the whole year respectively. Notably, Shenyang, Dalian, and Anshan were the top three cities in atmospheric emissions. In addition, the three kinds of pollutants mainly appeared in suburbs and decreased gradually from suburbs to urban areas.

Comparison on real-world driving emission characteristics of CNG, LNG and Hybrid-CNG buses

This study used a portable emission measurement system (PEMS) to investigate the emission characteristics of three Euro V buses (a CNG bus, an LNG bus and a hybrid-CNG bus) under real-traffic conditions. The results showed that the emission factor of gaseous pollutants decreased gradually with increasing driving speed. The LNG bus showed the highest emission characteristics, especially the emissions of CO, NOx, PM and BC. Although the NOx emission factor for the LNG bus was the highest (23.56 g/km), its NO2 emission factor (0.82 g/km) was lower than that of the CNG bus (1.58 g/km). Moreover, the particle size of the particulate matter emitted by the LNG buses was large, and the ratio of BC/PM was about 40%, which was much higher than those of the other two buses (7.59% and 33.11% for the CNG bus and hybrid-CNG buses, respectively). Compared with the CNG bus, the hybrid-CNG bus could effectively reduce particle number emissions by 59.1%, mainly by reducing the emission of nucleation-mode particles with particle size less than 30 nm. However, the emissions factors of other pollutants of the hybrid-CNG bus were higher than those of the CNG bus, especially the emission of black carbon, which was 66% higher.

Analysis of the Characteristics of Real-World Emission Factors and VSP Distributions—A Case Study in Beijing

Vehicle emissions intensity at a given travel speed is well known among the public since travel speed is the key parameter in both the traffic model and the emission model. Yet, several problems still remain in traditional approaches of measuring the emission intensity. To establish accurate and high-resolution emission factors, an established method of emission factors is proposed based on the real-time monitoring operation conditions data, which can reflect the effect of dynamic traffic changes on emissions. The speed-specific vehicle-specific power (VSP) distributions of different months, as well as those in different vehicles in Beijing were developed and compared. Statistical analyses such as Coefficient of Variation (CV) and Root Mean Square Error (RMSE) were used to quantify the differences in the VSP distribution. The results showed the significant correlation between the distribution of VSP, velocity, and operating patterns at time intervals within the annual range. Driving conditions in 2021 are more eco-friendly because of the improvement of digital development and driving habits. Furthermore, research on CO, HC, and NOx emission factor situations in different cycles revealed that the emission factors of NOx and HC are always underestimated in typical operating modes, while sometimes the emissions of CO are overvalued.

Evaluation of real-world emissions of China V heavy-duty vehicles fueled by diesel, CNG and LNG on various road types.

Natural gas has been widely considered as an alternative fuel to diesel on heavy-duty vehicles (HDVs). To evaluate the real-world emissions, 19 diesel HDVs, 3 CNG HDVs and 9 LNG HDVs were tested using portable emission measurement system on urban, suburban and freeway roads . The results show that average emission rates of CO, HC and NOx from diesel, CNG and LNG HDVs tend to rise with the increasing of VSP. Due to different emission control strategies and complicated driving cycle, NOx reduction rates of real-world emission factors are lower than those of the corresponding limits from China II to China V diesel HDVs. CO and NOx emission factors from all tested HDVs on urban road are generally higher than those on suburban road in the same velocity intervals, which means driving behaviors on different road types have great influence on emission factors in the same velocity intervals. NOx emission factors from LNG HDVs are higher than those from diesel HDVs, indicating that using China V LNG HDVs instead of China V diesel HDVs could not be an ideal alternative for freeway transportation. As CO and NOx comprehensive emission factors from China V CNG HDVs are higher than those from China V diesel, even higher than China IV diesel HDVs, China V CNG HDVs are unable to be considered as cleaner vehicles when compared to China V diesel HDVs in the study. It is noticeable that HC emission factors from CNG and LNG HDVs are extremely higher compare with diesel HDVS. NO2 emission factors from LNG HDVs are 2.14-9.19 and 4.74-8.53 times than those from diesel and CNG HDVs with various road types. Our study can provide development road map for different fuel types of HDVs and the reference for new emission legislation of HDVs.

Estimation of typical agricultural machinery emissions in China: Real-world emission factors and inventories

• The 8-mode testing cycle was unable to reflect actual engine performances. • NOx emission factors were higher than those of national inventory guideline. • Emission inventory based on harvesting area of corn combine harvester was established. • Emissions of corn combine harvesters in China mainly occur from June to October.

The Effect of Ignition Timing on the Emission and Combustion Characteristics for a Hydrogen-Fuelled ORP Engine at Lean-Burn Conditions

The application of hydrogen fuel in ORP engines makes the engine power density much higher than that of a reciprocating engine. This paper investigated the impacts of combustion characteristics, energy loss, and NOx emissions of a hydrogen-fuelled ORP engine by ignition timing over various equivalence ratios using a simulation approach based on FLUENT code without considering experiments. The simulations were conducted under the equivalence ratio of 0.5~0.9 and ignition timing of −20.8~8.3° CA before top dead centre (TDC). The engine was operated under 1000 RPM and wide-open throttle condition which was around the maximum engine torque. The results indicated that significant early ignition of the ORP engine restrained the flame development in combustion chambers due to the special relative positions of ignition systems to combustion chambers. In-cylinder pressure evolutions were insensitive to early ignition. The start of combustion was the earliest over the ignition timing of −17.3° CA for individual equivalence ratios; the correlations of the combustion durations and equivalence ratios were dependent on the ignition timing. Combustion durations were less sensitive to equivalence ratios in the ignition timing range of −14.2~−11.1° CA before TDC. The minimum and maximum heat release rates were 15 J·(°CA)−1 and 22 J·(°CA)−1 over the equivalence ratios of 0.5 and 0.9, respectively. Indicated thermal efficiency was higher than 41% for early ignition scenarios, and it was significantly affected by late ignition. Energy loss by cylinder walls and exhaust was in the range of 10~16% and 42~58% of the total fuel energy, respectively. The impacts of equivalence ratios on NOx emission factors were affected by ignition timing.

Assessing heavy-duty vehicles (HDVs) on-road NOx emission in China from on-board diagnostics (OBD) remote report data

Mobile source emissions are some of the major causes of air pollution across the world and are associated with numerous adverse health impacts. China has implemented increasingly stringent emission standards over the past few decades, the most recent one being the sixth emission standard (China VI) first rolled out in 2019. The China VI standard places special emphasis on tightening limits for NOx emission and introduces remote monitoring of vehicles' On-board diagnostics (OBD) data to reduce emissions from diesel and gas-powered heavy-duty vehicles (HDV).This paper aims to establish a methodology to calculate HDV NOx emissions on an extended timescale, and under real-world operations. OBD data was collected and examined from 53 China VI diesel HDVs and 14 China V diesel HDVs, which found that the average NOx emission factors are 1.420 g/km and 3.894 g/km for the two samples respectively; this indicates that the implementation of China VI standard helps to significantly reduce NOx emission from HDVs. Combining the emission factors and calculated travel distances collected by OBD and vehicle sales data, the China VI emission standard is estimated to have resulted in 43,969 tons of NOx emission reduction by the end of 2020. With China announcing country-wide enforcement of the new standard in 2021, >1.7 million tons of NOx emission could be avoided by 2023 annually.

Real-world emission factors for SUVs using on-board emission testing and geo-computation

A Portable Emissions Measurement System (PEMS) was used to measure emissions of five sports utility vehicles (SUVs) in a wide range of real-world driving conditions. The program included testing of fuel quality, coast-down and emissions in start, hot running and extended idling conditions. Geo-computation methods were used to add critical information (road gradient) to the PEMS data. Results from this study are generally in good agreement with international PEMS data. Hot running NOx emission factors are on average seven times higher than the type-approval limit for diesel SUVs, and they reach about 2100 and 400 mg/km in urban conditions for NOx and NO2, respectively. They are 7 (NOx) and 4 (NO2) times higher than current emission factors in COPERT Australia. COPERT Australia emission algorithms for CO2 are well behaved and the PEMS data suggest an update is not required. COPERT Australia emission algorithms should be revised for diesel SUVs (NOx, NO2) and petrol SUVs (CO, THC, NO2) to ensure accurate estimation of vehicle emissions at fleet level. Inclusion of logistic regression is proposed for future COPERT updates.

Emissions of gaseous pollutants released by forest fire in relation to litter fuel moisture content

The moisture content of forest floor fuel influences fire initiation and spread, but little is known about its impact on the emissions of pollutants. This study aimed to estimate quantitatively the characteristic change of pollutants emitted by forest fires at various fuel moisture content. Thus, litter fuel (both branches and leaves) of two dominant coniferous species (Cunninghamia lanceolata and Pinus massoniana) and two dominant broad-leaved species (Eucalyptus robusta and Cinnamomum camphora) in Southeast China were experimentally burned in an indoor biomass combustion facility, and smoke and non-methane hydrocarbons (NMHCs) were analyzed by gas chromatography-mass spectrometry. The results showed that CO, CO2, NOx, and SO2 reached peak concentrations faster at low moisture content. However, emission factors of CO increased, whereas emission factors of CO2, NOx, and SO2 decreased as the moisture content of fuels increased. Emission factors of CO, CO2, NOx and SO2 released from combustion of conifer fuels significantly increased with fuel moisture content compared to broad-leaved fuels. Total NMHCs emission was positively affected by the fuel moisture content. As the moisture content of the fuels increased, multi-branched and long-chain alkane emissions increased, whereas olefin and aromatic hydrocarbon emissions decreased but emissions of olefins and aromatic hydrocarbons with more branched chains increased. The findings provide valuable insight about the impact of forest fire on atmospheric environment and fire prevention measures.

An experimental investigation of particle and NOx emissions for a non-road diesel engine equipped with an integrated DOC + CDPF + SCR aftertreatment system during different operations.

An integrated aftertreatment system consisting of diesel oxidation catalyst (DOC), catalytic diesel particulate filter (CDPF), and selective catalytic reduction (SCR) is an effective way of reducing both NOx and particulate matter (PM). In this paper, the effect of DOC + CDPF + SCR on NOX and particle emissions is investigated during different operations to assess applicability of this aftertreatment for meeting more rigorous non-road emissions standard. Meanwhile non-negligible issue about regeneration emission is studied. The results show that the DOC + CDPF have no significant effect on NOx but increase the NO2/NOx ratio which is correlated with load. SCR is the main NOx reduction device with average efficiency of 86.5% for steady-state operations. Meanwhile, NH3 slip is lower than 16ppm. During cold and hot non-road transient cycles (NRTCcycles), average NOx efficiencies are 56.7% and 57.8%, respectively, along with NH3 slip below 10ppm. DOC + CDPF + SCR maintain filtration efficiency over 97% and 99% for PM and particle number (PN) for either steady-state operation or NRTCcycle, but particle size distributions change. Compared with the original emissions, NOx, PM, and PN emission factors are all below non-road China-IV limit after equipping with DOC + CDPF + SCR. However, during regeneration the aftertreatment does not maintain a high filtration performance but becomes particle generator. The penetration of nuclear particles and decomposition of agglomerated particles lead to high CDPF-out PN of 1.5 × 107 #/cm3-3.5 × 107 #/cm3. During regeneration, accumulated NOx is negligible, but the PM is 121.6 and 44.5 times higher than cold and hot NRTCcycles, respectively. In summary, DOC + CDPF + SCR is excellent way to improve non-road emissions but low SCR efficiency at low-temperature and high accumulated PM during regeneration process should be further addressed.