Impact of atmospheric emissions from ships in port on urban areas

Maritime transport, despite is one of the most efficient modes of transport, causes several major environmental problems, particularly about air pollution. Furthermore, due to the growth of the shipping activities, its environmental impact will be more relevant in the future. Because of the current environmental issues, the legislation on shipping emissions is frequently updated and becomes more and more stringent. Several policies were issued in the last decades, mainly focused on reducing the content of sulfur in marine fuels. The last international IMO-2020 regulation was enforced on 1 January 2020, it limits the sulfur content of any fuel oil used on board ships at a maximum of 0.50% m/m (mass by mass) outside emission control areas (ECAs) and 0.1% inside ECAs. Since 1 January 2021, in the Baltic and North Sea a nitrogen emission control area (NECA) was applied, requiring the ships built after 2021 operating in this area must respect a mandatory Tier 3 standard (80% reduction compare to Tier 1). The establishment of ECAs has become an important measure to reduce and control ship emissions. Even though, in-port emissions account for a relatively small proportion of the total emissions due to shipping, they can represent a significant impact on the health of population living in port cities and coastal areas. To accurately quantify the risk associated with atmospheric emissions of ships when in-port and the potential benefits of control measures, it is necessary to improve the state-of-art of both the estimation of emissions and the performance of atmospheric dispersion models. The aim of this thesis is to assess the impact of ship emissions in the port of Naples in 2018 by the development of a bottom-up procedure improving the state-of-art of present methodologies. Pollutants considered are NOx, SO2 and PM10. The developed methodology can be applied to any port. The first issue analysed in this thesis is the validation and the optimization of CALPUFF model when used to simulate the dispersion of the ship emissions in a port. With this aim wind tunnel tests and Computational Fluid Dynamics (CFD) numerical simulations were used to model the dispersion of atmospheric emissions of cruise ships at hoteling in the port of Naples. A part of the Naples urban area large about 1.2 km2 was reproduced at a scale of 1:500 for the wind tunnel experiments. The worst, but very frequent, emission scenario with three cruise ships emitting at the same time and wind blowing from the south-east with a speed at funnel height of 3 m/s in neutral stability conditions of the atmospheric boundary layer was studied. Two different values UR=1 and UR=4 of the ratio funnel gas velocity/wind speed were considered. In the wind tunnel experiments, Ethane was used as the tracer gas and its concentration was measured at 35 receptor points inside the urban area and at different heights. The dispersion of ship emissions in the same area was also studied by CFD simulations using steady-state solutions of the RANS equations with a k-ω shear-stress transport (SST) turbulence model. A very good agreement between wind tunnel and CFD results is observed. The same simulations were then performed with CALPUFF. The results were used to analyse the accuracy of the predictions of the dispersion model CALPUFF. The effect of two CALPUFF model options was studied: the building downwash module and the parameterisation of the dispersion coefficients. The CALPUFF results are less accurate than the CFD simulations and show a general tendency to underestimate the experimental data. However, the optimization process improves the performance of CALPUFF. A more comprehensive analysis of the effect of a varying UR in the range 0.25 – 16 was also undertaken using numerical models. The second step was the creation of a comprehensive global data base of all ships visiting the port of Naples in 2018. Using AIS data a data base containing the main information of more than 900 ships (category, name, IMO number, gross tonnage, deadweight; length, width, draft, total power installed onboard and the type of engines; maximum speed; the number of passengers, cars, containers) was created. All ships were lumped in 45 categories and five macro-categories (Commercial, Fishery, Passenger, Tanker, and Other). To fill the missing data, regressions based on real data for each category were adopted. Once created this "static" database, AIS data were processed through a MATLAB code which is able to identify the phase of ships on the basis of the analysis of the temporal data, of the time delta between records, and of the speed data. The phases defined are as follows: entry to the port, navigation in the port, the start, stop, and end phases of mooring at the quay, exit from the port, and engine start and stop. In this way at each AIS record is associated a specific activity-phase of the ship. Once all this information was completed, emission rates of NOx, SO2, and PM were calculated. Great accuracy was applied to the evaluation of the real power of main engines starting from the average speeds when ships are moving in port with respect to that using the typical load factors corresponding to the cruise phase. Similar accuracy was also applied to the evaluation of the total power of auxiliary engines both during the navigation and hoteling phases. The reference adopted is the recent EMEP/EEA guideline using specific emission factors defined for each category of ships and activity phase. AIS data were also used to identify in and out routes and mooring piers for each ship category. For the sake of simplicity piers and routes were merged when very close each other. In parallel to this approach, typical of bottom-up procedures, a statistical study based on data from 38 ports all over the world in 45 annualities was performed with the aim to correlate emissions with traffic data per year. Traffic data considered are: number of passengers, hours spent in each phase, number of calls for passenger ships; and tons of good, hours spent in each phase and number of calls for commercial ships. The correlation with traffic data gives the possibility of an easy check of the emissions estimated but show, as expected, a certain degree of uncertainty. Once verified and optimized the accuracy of CALPUFFF simulations, the complete emission inventory developed for the port of Naples was used as input to CALPUFF together with meteorological data. The results of simulations were compared with data from fixed monitoring stations in the urban area both as annual average and percentile. In this way the impact of ship emissions on air quality in Naples in 2018 was assessed. The research provides at the same time useful insights on the contribution of ship emissions to air pollution in Naples and on an accurate procedure to assess the impact of ship emissions in port cities

Development of a Methodology for the Identification of High Emitting Mobile Sources in Narrow and Deep Street Canyons

In urban areas transport represents a significant source of atmospheric pollutants and greenhouse gases (GHG). In the case of vehicular transport, a significant contribution to total emissions is given by a category of vehicles with excessively high emissions of one or more pollutants defined as high emitting vehicles (high-emitters). High emitters can contribute a disproportionally way to total emissions of many airborne pollutants (NOx, COV, PM and GHGs). Remote sensing (RS) techniques have been developed with the aim to identify high emitterss but until now they have found only few practical applications. Among RS technologies, point sampling (PS) is the most promising for implementation in narrow and deep street canyons due to the limited impact on both pedestrians and architecture and the small space occupancy. In this paper we present results of preliminary monitoring campaigns carried out in a narrow and deep street canyon in Naples (Italy) in low-traffic conditions. Fine particles (FPs) concentration (20-1000 nm) were monitored using a condensation particle counter (CPC). Time patterns of FPs concentration have been analyzed by a code developed in MATLAB to identify FP concentration peaks and successively to attribute each identified peak to a specific vehicle. To study the effect of operating conditions (wind speed and direction) on the plume formed by vehicle exhausts, CFD simulations have been also carried out. Results show good performances of the code in the identification of FPs peaks and a limited effect of ambient parameters on the dispersion of the plumes inside the street canyon studied

Long-Term Monitoring of a Surface Flow Constructed Wetland Treating Agricultural Drainage Water in Northern Italy

Agricultural drainage water that has seeped into tile drainage systems can cause nitrogen and phosphorus pollution of the surface water bodies. Constructed wetlands (CWs) can help mitigate the effects of agricultural non-point sources of pollution and remove different pollutants from tile drainage water. In this study, hydrological and water quality data of a Northern Italian CW that has been treating agricultural drainage water since 2000 were considered to assess its ability to mitigate nitrogen and phosphorus pollution. The effects of such long-term operation on the nutrients and heavy metals that eventually accumulate in CW plants and sediments were also analysed. Since 2003, the CW has received different inflows with different nutrient loads due to several operation modes. However, on average, the outflow load has been 50% lower than the inflow one; thus, it can be said that the system has proved itself to be a viable option for tile drainage water treatment. It was found that the concentration of nitrogen and phosphorus in the plant tissues varied, whereas the nitrogen content of the soil increased more than 2.5 times. Heavy metals were found accumulated in the plant root systems and uniformly distributed throughout a 60 cm soil profile at levels suitable for private and public green areas, according to the Italian la

Biotechnological synthesis of succinic acid by actinobacillus succinogenes by exploitation of lignocellulosic biomass

Succinic acid is increasingly used in pharmaceutical industries, for the production of additives in food industries, in agriculture and in refinery processes as a precursor of many chemical compounds among which the most important is the succinate salt. It is also used as an ion chelator and surfactant, and for the biochemicals production. Currently, succinic acid is mainly produced through chemical petroleum-based processes, usually from n-butane using maleic anhydride. However, the use of petrochemical feedstocks raises serious environmental problems, due to the higher values of temperature and pressure required. The biotechnological production of succinic acid by microbial conversion of lignocellulosic biomass is attracting growing interest due to the environmental and economic advantages offered. This research is focused on the exploitation of Arundo donax (Giant reed) as a source of lignocellulosic biomass. Arundo donax is a perennial crop particularly suitable for energy production, as it offers high yields per hectare, even in partially fertile or polluted soils, not used for agriculture. Hydrolyzate of Arundo donax will be used as growth media for the Actinobacillus succinogenes 130Z, a bacterium typically found in the bovine rumen, that is recognized as one of the most promising for the biotechnological production of succinic acid, as it is able to produce higher concentrations of succinic acid. The experimental analysis is carried out to optimize the production of succinic acid taking into account the effect of the most critical parameters of the process (microbial biomass, pH, reducing sugars, volatile fatty acids, and succinic acid). Tests have shown that in 48h the sugars are completely biodegraded with a total production of bio-succinic acid of 5.9 g for 9.1 g of reducing sugars, an hourly production 0.12 g h-1 with a yield equal to 65%

Biochar addition in the anaerobic digestion of the organic fraction of municipal solid waste for biogas production

The continuous decline of fossil fuel availability and the ever increasing concern about environmental pollution, expressed by scientists, governments and public at large, are stimulating the research on renewable energy production. In this perspective, anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is recently meeting with increasing interest. It is a process viable both from an economic and technological standpoints, capable to combine the environmental friendly re-cycle of large amount of OFMSW combined to the production of methane, an excellent fossil-based fuels substitute (Chatterjee and Mazumder, 2016). Please click on the file below for full content of the abstract

The Potential Role of Hybrid Constructed Wetlands Treating University Wastewater\u2014Experience from Northern Italy

University wastewater is a type of wastewater with higher pollutants load and flow rate variability than typical domestic wastewater. Constructed wetlands (CW) could be used for university wastewater treatment and consequently for wastewater reuse. A hybrid CW pilot plant, at the University of Bologna (Italy), was monitored to assess its potential to be used at the university. Its treatment performance was monitored for one year and public acceptance explored through a survey. The pilot plant had two treatment lines, (1) a vertical flow CW (VFCW) and a planted horizontal flow CW (HFCW), and (2) the same VFCW and an unplanted horizontal flow filter (HFF). The HFCW achieved higher removals than the HFF, but it was also found to be prone to higher water losses. However, both treatment lines met the Italian limits for discharge in natural water bodies and some of the limits for wastewater reuse in Italy and the EU. The VFCW alone was not able to meet the same limits, demonstrating the advantages of hybrid over single stage CWs. A positive attitude towards CWs and wastewater reuse was found among the survey participants. Therefore, hybrid CWs (planted and unplanted) are considered a feasible technology for application at universities

Nitrogen Recycling in Closed Cultures of Litopenaeus vannamei (Boone 1931) with Different Artificial Substrates

Abstract Litopenaeus vannamei juveniles (5.6±0.6 g), at an initial density of 152 individuals/m 2 , were grown for 28 days in 12 cylindrical 1,000-l tanks with no water exchange. Three tanks had 7.1 m 2 Aquamats® to promote periphyton growth, and six had 7.1 m 2 geotextile fabric or mosquito net (three for each substrate). The remaining three served as controls. The shrimp were fed 35% protein shrimp feed, twice daily, supplied on demand. There were no differences in dissolved TAN or unionized ammonia (NH 3 ) concentrations between treatments with substrates, but they were significantly lower than in the control. N-NO 3 -values were higher in tanks with substrates, possibly indicating faster nitrification rates. These tanks produced shrimp with higher mean individual weights and growth rates than the control, but the final yield in tanks with mosquito netting was intermediate between the control and the remaining treatments. The highest feed and economic feed conversion indices, and the lowest nitrogen utilization and protein efficiency ratio, were in the control, and there were no differences between the three treatments with added substrates, showing that the less expensive geotextile fabric and mosquito net may be used with the same efficiency as Aquamats® in periphyton-based aquaculture

On the Emergy accounting for the evaluation of road transport systems: an Italian case study

Road transportation is one of the most polluting as well as energy-intensive sectors, and requires planning policies capable to address at the same time several different environmental, social, and economic issues. Cost-benefit analyses are generally carried out with a major focus on fuelling and driving efficiency, whereas a systemic approach appears to be needed for a more comprehensive evaluation of the alternatives that may become available to address any issue, be it intended for either short-term or long-term spans. For instance, building up a new infrastructure might allow for savings in time or fuel per km, but this may require an equivalent or even higher socio-environmental investment. In this work, a short review is presented of some systemic studies on transportation that use the emergy synthesis methodology. A case study is also addressed, concerning recent important expansion works on the Apennine Mountains section of the Italian major highway A1. In particular, the analysis points out the role of time saving, since for a new or renewed transport infrastructure (and when comparing for example road to rail transport) saved time is likely to become crucial in justifying civil enterprises. Nevertheless, the present emergy synthesis and the teaching of H.T. Odum (Odum & Odum, 2001) warn us that such “luxury” highly depends on the abundance of available energy, which is less and less given for granted, whereas a systemic analysis approach may indicate different levels of criticality when oriented towards environmental and well-being issues

A global observational analysis to understand changes in air quality during exceptionally low anthropogenic emission

This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015–2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O3 and the total gaseous oxidant (OX = NO2 + O3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015–2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO2 and NOx concentrations and peoples’ mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO2 and between 30% and 40% in mean PM2.5 concentrations over 2020 full lockdown compared to the same period in 2015–2019. However, PM2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO2/CO ratio). Some Chinese cities showed similar increases in PM2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of ~70%. The SO2 anomalies were negative for 2020 compared to 2015–2019 (between ~25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to ~40%. The NO2/CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO2 decrease due to the general reduction in mobility (ratio of ~60%). Analysis of the total oxidant (OX = NO2 + O3) showed that primary NO2 emissions at urban locations were greater than the O3 production, whereas at background sites, OX was mostly driven by the regional contributions rather than local NO2 and O3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required.Peer reviewedFinal Published versio