Sulfur Oxide Emissions Research Articles

Genomic analysis and biodesulfurization potential of a new carbon-sulfur bond cleaving Tsukamurella sp. 3OW.

Direct combustion of sulfur-enriched liquid fuel oil causes sulfur oxide emission, which is one of the main contributors to air pollution. Biodesulfurization is a promising and eco-friendly method to desulfurize a wide range of thiophenic compounds present in fuel oil. Previously, numerous bacterial strains from genera such as Rhodococcus, Corynebacterium, Gordonia, Nocardia, Mycobacterium, Mycolicibacterium, Paenibacillus, Shewanella, Sphingomonas, Halothiobacillus, and Bacillus have been reported to be capable of desulfurizing model thiophenic compounds or fossil fuels. In the present study, we report a new desulfurizing bacterium, Tsukamurella sp. 3OW, capable of desulfurization of dibenzothiophene through the carbon-sulfur bond cleavage 4S pathway. The bacterium showed a high affinity for the hydrocarbon phase and broad substrate specificity towards various thiophenic compounds. The overall genome-related index analysis revealed that the bacterium is closely related to Tsukamurella paurometabola species. The genomic pool of strain 3OW contains 57 genes related to sulfur metabolism, including the key dszABC genes responsible for dibenzothiophene desulfurization. The DBT-adapted cells of the strain 3OW displayed significant resilience and viability in elevated concentrations of crude oil. The bacterium showed a 19 and 37% reduction in the total sulfur present in crude and diesel oil, respectively. Furthermore, FTIR analysis indicates that the oil's overall chemistry remained unaltered following biodesulfurization. This study implies that Tsukamurella paurometabola species, previously undocumented in the context of biodesulfurization, has good potential for application in the biodesulfurization of petroleum oils.

To Study the Effects of Microemulsion Based Hybrid Biofuel on Emission Characteristics of CI Engine: A Short Review

AbstractMicroemulsion based fuels (MBF) have gained significant attention in recent years due to their potential to enhance combustion efficiency, reduce emissions, and improve overall engine performance. This research paper enlightens the effects of physiochemical properties on the emission characteristics of CI engine. The microemulsions are formulated using surfactants, co‐surfactants, water or alcohols, and fuel components. The effects of density, viscosity, calorific value, cold flow properties, and cetane number along with the stability and the multi‐component characteristics of (MBF) has been taken into consideration to examine its effects on Emission characteristics such as nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), particulate matter (PM), and unburned hydrocarbons (UHC). Microemulsion‐based fuels lower emissions of NOx and PM, recognized to the more complete combustion. The review highlights various studies that have investigated the benefits of microemulsion fuels, including reduced emissions of different pollutants and thus reduce the adverse effect on environment.In conclusion, microemulsion‐based fuels show likely physiochemical properties, as well as favorable emission characteristics, with reduced NOx, SOx, CO, PM, and UHC emissions. This study highlights the potential of microemulsion‐based fuels as environment friendly alternatives, flagging the way for further research.

Environmental regulation and intermediate imports: Firm-product-level evidence

This study examines the effects of domestic environmental regulations on import activity. Using a panel of firm-product-level data and variations in regulatory stringency across products established by China’s Eleventh Five-Year Plan for Environmental Protection (covering 2006–2010), it reveals that tougher regulations on emission-intensive industries at home led to increases in downstream manufacturers’ imports of emission-intensive intermediate inputs. Specifically, a 1% increase in sulfur dioxide emission intensity resulted in a 0.026% increase in intermediate imports after the implementation of the regulation. A back-of-the-envelope calculation suggests that, although the regulation increased emissions in source countries, it reduced global emissions of sulfur oxides and carbon dioxide. This is because the increases in imports caused by the regulation mainly came from countries with lower emission intensity than China. The regulation did not disproportionately increase imports from or emissions in developing countries.

Experimental Investigation of Sulfur and Nitrogen Oxide Emissions and Corrosion Propensity During the Combustion of Coals and Biomass Fuels

ABSTRACT The increasing use of biomass in Indonesian coal-fired power plants, mainly through co-firing, presents challenges due to different fuel characteristics, which can affect gas emissions, ash deposition, and combustion efficiency. This study assesses flue gas emissions (SO2 and NOx) and corrosion tendencies of various biomass types and coal. The study begins with characteristic testing and ash analysis of coal and biomass samples, including proximate, ultimate, and calorific value analyses, to determine their suitability as fuels. Preliminary calculations predict flue gas emissions and ash deposit formation, followed by laboratory-scale combustion experiments using a DTF to assess flue gas and ash deposit characteristics. The results show that sulfur in biomass is converted to the gas phase up to 99%, while in coal, it is converted up to 95% at high temperatures. NOx levels are primarily affected by the nitrogen contents of the fuels; for instance, Coal-B at 0.88 wt% produces less NOx than solid recovered fuel (SRF) and refused derived fuel (RDF) with 1.73 wt% and 1.51 wt%, respectively, yet still generates higher emissions than the other three biomass types. In general, wood chips (WC), rise husk (RH), and palm kernel shell (PKS) emit 30–80% less flue gas compared to coal. However, ash deposition results indicate that PKS, SRF, and RDF exhibit corrosion tendencies due to the dominance of albite (NaAlSi3O8) in the mineral phase. Additionally, the high chlorine content in SRF (0.544 wt%) and RDF (0.224 wt%) leads to the formation of sticky ash deposits, which potentially impact heat transfer surfaces. These findings contribute to identifying suitable biomass types for both co-firing or dedicated combustion in coal-fired power plants.

Mechanism study on quantification of sulfurization effect on methane decomposition with CuO oxygen carrier

The sulfur-containing impurity in natural gas, coal, and organic solid wastes generally exerts significant impacts on the dynamic evolution of sulfur oxides emission in atmosphere, and results in the degraded reaction performance of chemical looping process. Methane is the main component of natural gas and a typical pyrolysis and gasification product of solid waste, so it is of great significance to quantify the toxicological effects on the conversion of methane. this work realizes the accurate prediction of methane heterogeneous conversion in a multiscale kinetic model, and innovatively establishes a framework for quantifying the toxicological effect on the oxygen carrier particles. The kinetic parameters of methane oxidation over fresh and sulfurized oxygen carriers are calculated using density functional theory, and the sensitivity analysis of rate constant is conducted to forecast the priority of different reactions. Results indicate that the effect of residual sulfur in oxygen carrier is complex and not monotonically inhibited, and the sulfurization significantly limits the methane oxidation reactivity by reducing the reaction rate of the rate-limited dissociation step under the high-temperature condition. The multi-scale kinetic simulations reveal that the maximum instantaneous rate of sulfurized oxygen carrier is decreased by 7.45 %, which is deemed as the attenuation factor of 0.9255 derived from the toxicological effects of sulfurization.

Transition to the New Green Maritime Era—Developing Hybrid Ecological Fuels Using Methanol and Biodiesel—An Experimental Procedure

The conventional utilization of fossil fuels precipitates uncontrolled carbon dioxide and sulfur oxides emissions, thereby engendering pronounced atmospheric pollution and global health ramifications. Within the maritime domain, concerted global initiatives aspire to mitigate emissions by 2050, centering on the adaptation of engines, alteration of fuel compositions, and amelioration of exhaust gas treatment protocols. This investigation pioneers experimentation with marine gas oil augmented by methanol, a practice conventionally encumbered by prohibitively expensive additives. Successful amalgamation of methanol, animal-derived biodiesel, and marine gas oil (MGO) is empirically demonstrated under meticulously controlled thermal conditions, creating a homogeneous blend with virtually zero sulfur content and reduced carbon content, featuring characteristics akin to conventional marine gas oil but with no use of expensive emulsifiers. This new blend is suitable for employment in maritime engines utilizing Delaval technology, yet with significantly lower energy requirements compared to those necessitated using conventional very low sulfur fuel oil (VLSFO) with a maximum sulfur content of 0.5% w/w.

Investigation on the effect of ship emissions on the air quality, A case study in Hainan Island, China

This paper presents an air quality simulation model that incorporates shipping activities and weather conditions, with a case study of Hainan Island to examine the impact of ship emissions on air quality. The findings reveal that the density of automatic identification system (AIS) signals is particularly high in the southern coastal regions. The results showed that the annual ship emissions recorded the highest density of 896.7 tons/0.01°, 49.8 tons/0.01°, 1139.7 tons/0.01°, and 122000 tons/0.01° for sulfur oxides (SOx), particulate matter (PM), nitrogen oxides (NOx), and carbon dioxide (CO2), respectively. Furthermore, the partial distributions of these emissions were not significantly affected by the seasons. Ships within twelve nautical miles of Hainan coastlines emit approximately 2817.7 tons of SOx, 14686.4 tons of NOx, 630.4 tons of PM2.5, and 416.9 tons of hydrocarbons (HC) annually. These emissions are primarily concentrated in the sea areas surrounding the ports of Haikou, Yangpu, Basuo, and Sanya. Ships manufactured between 2000 and 2010 have contributed significantly to air pollution, with SOx and HC emissions accounting for approximately 51% and 56% of total emissions, respectively. However, for ships manufactured after 2016, these proportions have dropped to approximately 10%. In terms of air pollutants from ship emissions in Hainan Island, the spatial distribution of their contributions is significantly uneven. The impact of PM2.5 differs significantly depending on the season, with the concentrations being substantially higher during Spring. However, the proportions of O3 and other pollutants do not vary significantly, except during Spring.

Characterization of biodiesel blends produced from repurpose used cooking oil

Characterising the fuel before it is used in an engine is necessary for a healthy fuel supply for an engine, just as a clean environment is necessary for a healthy life. Used cooking oil (UCO), a third-generation feedstock, is investigated for its physicochemical properties. To ascertain the blend's suitability as an alternative fuel, characterisation was conducted using GC-MS, thermogravimetric, infrared spectroscopy and element analysis. To enhance the characteristics the oxygenated additive (diethyl ether: DEE) was added at higher proportions. In accordance with Indian requirements, the impact of DEE on the physicochemical characteristics of biodiesel blends was examined (IS1448). Oleic acid keeps RUCO-B's fuel mixture well in terms of viscosity, ignition quality and oxidative stability. Sulphur-free technology on the RUCO-B eliminates sulphur oxide emissions automatically. The physical (density and viscosity), chemical (cetane number and calorific value) and cold flow (flash point, pour point and cloud point) characteristics of ternary blends were all enhanced by the addition of DEE. According to ASTM D975, the blend's 4% DEE surpasses the standard's acid value by 36%, potentially causing engine damage. In ternary blends, the DEE proportion (0.8, 1.6, 2.4 and 3.2%) enhances the cold flow, chemical and physical qualities.

Nitrogen and Sulfur Oxides Emissions from Fuel Oil Combustion in Industrial Steel Reheat Furnace

Many industrial heating operations still use fueloil for combustion instead of the cleaner gaseous fuels. Inthe steel industry, large furnaces referred to as reheat furnaces are used to heat steel stocks to rolling temperaturesusing normally fuel oil for combustion. The combustionproducts of flue gases consist of mainly carbon dioxide,water vapor and traced of other oxides such as nitrogen andsulfur oxides. These oxides are of a concern to theenvironment and should be minimized as much as possible.Experiments were carried out on a steel billet reheatfurnace in which air/fuel ratios are varied while the nitrogenoxide content is being monitored using furnace instruments.These variations in air/fuel ratios for combustion are foundto affect the concentration of nitrogen oxides in the flue gaswhere higher air/fuel ratios promoted the formation ofhigher nitrogen oxides during combustion. The sulfurdioxide content in the flue gas was calculated based onactual measurements of air and fuel rates to the furnace andfound to be minimal in the flue gas.

Digital disruption and energy efficiency: The impact of regional digitalization on China's industrial sector

Using the unique micro-data of industrial enterprises' Nitrogen oxides (NOx) and Sulfur oxides (SOx) emissions covering 58,725 enterprise-year observations, this paper investigates how digitalization affect energy efficiency. The empirical results show that regional digitalization can significantly promote the improvement of energy efficiency of industrial enterprises. Specifically, the result of PSM-DID method indicates that the impact of digitalization on energy efficiency is significantly enhanced by the “National innovative pilot cities” policy, while the dynamic result validates the continuity of industrial enterprises' energy efficiency. Moreover, regional digitalization has superior impact on enterprises within eastern region enterprises, the manufacturing sector, and with elevated liquidity and profitability levels. Finally, moderating effect suggests that technological innovation expand the positive impact of digitalization on enterprises’ energy efficiency. This study confirms regional digitalization can promote the energy efficiency of Chinese industrial enterprises, providing the policy suggestions to the energy transition in China.

Desulfurization of Gasoline and Diesel by Fly Ash‐Derived FAU Zeolite

AbstractSulfur in fossil fuels is a major environmental and public health concern worldwide due to emissions of sulfur oxides formed during combustion. This may require new developments or upgrades of existing refining technologies. Hence, further desulfurization of gasoline and diesel to combat hazardous emissions could be a significant step toward environmental protection. In this study, adsorptive desulfurization of gasoline and diesel was achieved using a low‐cost fly ash‐derived faujasite (FAU) zeolite as complementary to the conventional hydrodesulfurization method. Sulfur levels of fuel samples, brought to the laboratory from typical fuel stations, were detected by a turbidimetric method before and after desulfurization. FAU zeolite sorbent, prepared from coal fly ash, was contacted with the fuel samples at stopped flow, and the residual fuels were analyzed to determine the sorbent's desulfurization performance. The process was optimized to enhance the sorbent's performance by varying the reaction conditions such as temperature, fuel volume, and the sorbent chemical composition. The results indicated that, at ambient temperature and pressure, the zeolitic desulfurization could reduce the sulfur content approximately by 40 % of its initial concentration, from 61 to 37 ppm and 155 to 97 ppm, in gasoline and diesel, respectively. Therefore, fly ash zeolites offer a possible opportunity for further desulfurization of refining petroleum fuels which may lead to economic and environmental gains.

SIMULATING THE EFFECTS OF EURO 4 DIESEL-POWERED ENGINE JEEPNEYS ON AIR QUALITY AND UNDERSTANDING ESTIMATED HEALTH RISK TOWARDS SUSTAINABLE TRANSPORTATION

Abstract. The Euro-4 diesel-powered engines are the current industry standard in the Philippines as indicated in the Public Utility Vehicle Modernization Program (PUVMP) Omnibus Guidelines Department Order 2017-011. Based on the National Emissions Inventory report of the Environmental Management Bureau in 2018, 74% of air pollutant concentrations were produced by mobile sources including jeepneys. The PUVMP is focused on enhancing environmental sustainability, air quality, and in providing a reliable and effective public transportation system. The potential advantages to air quality and health from the full implementation of the program especially the Euro 4 diesel-powered engine jeepneys in Trece Martires City are assessed in this paper. The study aims to estimate the impact of the possible enforcement of Euro 4 diesel-powered engine jeepneys on the reduction of air pollution in the research locale. Four pollutants were assessed particularly Carbon Monoxide (CO), Nitrogen Oxide (NOx), Sulfur Oxide (SOx) and Particulate Matter 2.5 (PM2.5) using AERMOD Air Dispersion Modeling Software in five (5) different scenarios: (1) baseline engine jeepneys, (2) 25% implementation of Euro 4 diesel-powered engine jeepneys, (3) 50% implementation of Euro 4 diesel-powered engine jeepney, (4) 75% implementation of Euro 4 diesel-powered engine jeepneys and (5) full implementation of Euro 4 diesel-powered engine jeepneys. AirQ+ was utilized to evaluate the health risk of Euro 4 diesel-powered engine jeepneys to the drivers and commuters in the vicinity. Result shows that the Scenario 5 or the full implementation of Euro 4 diesel-powered engines relatively reduces CO by 84.30% (8.355 μg/cu.m to 1.31 μg/cu.m), NOx by 21.76% (10.6 μg/cu.m to 8.27 μg/cu.m), and PM2.5 by 83.36% (2.69 μg/cu.m to 0.447 μg/cu.m), by its maximum estimated concentrations. However, an increase by 14.14% of SOx emissions (0.091 μg/cu.m to 0.104 μg/cu.m) were seen on the simulation from Scenario 1 to Scenario 5. In terms of health risk assessment, higher levels of PM2.5 exposure exhibit an increase in health hazard with respect to mortality rate. Simulation outputs indicate that transitioning of jeepneys from current technology to Euro 4 models reduces pollution levels and lowers health risk, hence, can be used as basis in enhancing transport plans and health monitoring strategies in the city.

A Comparative Study of SOx, NOx, PM2.5 and PM10 in the UK and Poland from 1970 to 2020

Presently, there is growing discourse surrounding climate change, global warming, and the possibility of urban smog. Daily, we encounter air pollutants unwittingly, often oblivious to the substantial adverse impacts they may impart on our health. This manuscript furnishes a thorough examination of the shifts in the concentrations of distinct air pollutants, namely, sulphur oxides (SOx), nitrogen oxides (NOx), and particulate matter PM2.5 and PM10, within the contexts of the United Kingdom (a country progressively transitioning to alternative energy sources) and Poland (a country in the EU with the second lowest climate policy evaluation in the climate change performance index or CCPI) from 1970 to 2020. This comparative study between the two countries clearly showed the importance of the transition to clean energy sources. The UK’s efforts towards cleaner energy sources have led to reduced emissions of sulphur oxides (SOx) and particulate matter. In contrast, Poland’s heavy dependence on energy primarily from coal over the years has resulted in elevated pollution levels, notably in the concentration of pollutants such as particulate matter. This study also revealed that changes in emissions predominantly stem from technological advancements and economic activities. Additionally, political regulations and the gradual phase-out of specific fuels or energy-rich substances and their substitution with alternative energy sources have also imparted considerable influence.

Preliminary assessment of volatile organic compounds and hazardous gases dispersion at low winds: case study of Mellitah Gas Complex, Libya

Air pollution from industrial areas has become really worrying especially for city dwellers. The plume dispersion emitted from industrial sources is subject to several factors: temperature and emission rate velocity, wind speed and direction, source height, and atmospheric stability. This study aimed to evaluate the applicability of the dispersion coefficients correlated within a Gaussian plume approach to an industrial source in Libya (Mellitah Gas Complex) under low and moderate wind speeds. To this end, we have developed a specific code based on the Gaussian method to study the dispersion of (1) Volatile Organic Compounds (VOCs) from oil storage tanks and condensate storage tanks, and (2) sulfur oxides (SOx) and nitrogen oxides (NOx) emitted by the flaring process through three stacks of 80 m height. The emissions from multisource points and their dispersion have been predicted at calm wind conditions and the flammability and danger-prone toxic zones have been delimited around the studied site. The obtained results reveal that the emissions, particularly generated at low and moderate wind speeds, induce a dispersion with high concentration levels in the area surrounding the industrial site. The VOCs critical concentration region indicates a real risk of flammability at low-speed wind and stable atmospheric condition, from a height of 5 m above the ground. In fact, the VOCs concentration reach the Flammability Inferior Limit value of 0.018 m3 VOCs/m3 and these concentrations, appearing in the form of a plume, extend downstream to approximately 1000 m. The dispersion of NOx and SOx emissions downwind from the stacks are enhanced by wind speed; nevertheless, at 2 m height from the ground, the levels could exceed the limit value of 0.125 mg/m3, especially under the condition of unstable and very unstable atmospheric classes. From our findings, we recommend continuous monitoring campaigns inside and around the complex of Mellitah to ensure an environmentally secure zone that respects safety and health guidelines. Furthermore, enhanced simulations based on hourly weather conditions for extended area would be of great interest to accurately assess the air quality index in the region.

Costs of Coal Abatement for Residential Heating to Reduce Urban Air Pollution in Asian Russia: Evidence from Krasnoyarsk

Heat and electricity generation are major sources of air pollution in many large cities worldwide. In Siberian cities, the heat supply significantly contributes to air pollution, as coal remains the primary energy fuel in most of Asian Russia. Krasnoyarsk, the second-largest city in the macro-region by population, serves as a clear example of urban air pollution. In recent years, public authorities have implemented several measures to reduce pollutant emissions. These measures include modernizing thermal power stations, replacing inefficient small boiler houses, and converting residential heating to more environmentally friendly types of fuel. However, our analysis shows that these policies have not yet resulted in a significant transition away from using coal for heating. One of the primary reasons is that alternative fuels are unable to compete with coal in terms of price. The proposal suggests transitioning private households to pellet heating. Our goal is to evaluate the potential environmental and economic impacts of this measure. We estimate the necessary subsidy size for the successful implementation of both initiatives. In conclusion, converting households from coal to pellet heating can reduce the emissions of nitrogen oxides, carbon monoxide, sulfur oxides, and suspended particles by 0.2%, 8.5%, 4.4%, and 2.7%, respectively, of the total pollutant emissions in Krasnoyarsk. Furthermore, this conversion can provide economic benefits by supporting local pellet producers who heavily rely on export markets. If practically implemented, the proposed approach could solve one of the most significant development issues of one of the largest Russian cities within a few years, with only 2.5% of the annual city budget expenditure.

Modelling and Simulation of a Wet Scrubber System

Shipping is a relatively clean transport method with low emissions per ton-mile compared with road transport. However, harmful emissions emitted in coastal areas are a concern, as these affect local air quality and health. To reduce sulphur oxide (SOX ) emissions, the International Maritime Organization (IMO) implemented a global sulphur cap of 0.5 wt% and the 0.1 wt% limit in emission control areas (ECAs). Ship owners can opt for either low sulphur fuels or wet scrubber systems. Wet scrubber systems are a reliable method for reducing SOX emissions with capture rates of up to 98%. These systems may use seawater alkalinity or caustic soda (e.g. closed-loop systems) to neutralise the SOX emissions. However, the dynamic loading of engines can cause large fluctuations in the exhaust flow conditions, and it is unknown how these affect the effectiveness of the scrubber. This study explores the impact of dynamic loads on the SOX removal efficiency of closed-loop wet scrubbers. A dynamic model of a closed-loop wet scrubber utilising fresh water and caustic soda is developed and verified using publicly available data. The model applies the two-film theory to model the gas-liquid interface. Billet and Schultes liquid hold-up theory is used to model the liquid film thickness in the packed bed. Maintaining scrubber efficiency with large load fluctuations or high-frequency fluctuations requires an increased liquid flow. The scrubber control system used a set-point of 75% of the equivalent compliance limit to ensure compliance with the 0.1% ECA limit during load fluctuations. The model and results can be used to develop a more advanced control system for improved scrubber operation and integration with a selective catalytic reduction (SCR) system to demonstrate compliance with the IMO NOX Tier III limit when using high-sulphur heavy fuel oil (HFO).

A benchmarking analysis on electric vehicle emissions of leading countries in electricity generation by energy sources

A benchmarking analysis on vehicle emissions has been performed in this study. Sport Utility Vehicle (SUV) powered by electricity is taken into consideration in emission analysis. Calculations have been conducted for leading G20 countries in certain energy sources in electricity generation. According to the analysis, most optimal results are obtained in Volatile Organic Compounds (VOC), Carbon Monoxide (CO), Particulate Matters (PM10 & PM2.5), Sulfur Oxides (SOx), and Carbon Dioxide (CO2) emissions, if the vehicle is charged in France. Only Nitrogen Oxides (NOx) emissions are calculated as to be the lowest values in Canada, compared to other countries. Emissions of an average SUV Internal Combustion Engine Vehicle (ICEV) powered by gasoline are also added to the comparison.

Optimal Shipping Route under the Designation of the Mediterranean Sulfur Emission Control Area: Mathematical Models and Applications

In order to tackle sulfur oxides (SOx) emissions from maritime activities, both local governmental bodies and the International Maritime Organization (IMO) have implemented a range of regulations with the establishment of sulfur emission control areas (SECAs) being one crucial measure. Recently, the IMO made the significant decision to designate the Mediterranean as an SECA, aiming to promote environmental conservation as well as sustainable development in the maritime industry and mitigate the adverse health effects caused by air pollutants emitted from ships in Mediterranean regions. While this policy signifies significant progress in the reduction of sulfur emissions, it simultaneously presents intricate challenges for maritime enterprises. Notably, under the Mediterranean SECA designation, shipping companies may opt to bypass this region and choose routes through the Cape of Good Hope as a means of minimizing the overall costs, resulting in a potential increase in global carbon emissions. To support shipping companies in formulating optimal strategies within the framework of this new policy, the research introduces advanced techniques to make the optimal decisions concerning route selection, sailing speeds, and the appropriate number of ships for both SECAs and non-SECAs. Furthermore, we elucidate how these optimal decisions can be dynamically adapted in response to the dynamic fluctuations in fuel prices and the weekly operational expenditures incurred by maritime fleets. In the experimental results, taking into account factors like route distance and fuel costs, shipping companies select routes through the Mediterranean region in both eastward and westward directions. The total cost amounts to $6,558,766.78, utilizing eight vessels. Regarding ship speeds, vessels sail at reduced speeds in SECAs compared to non-SECAs. Furthermore, longer voyage distances require deploying a greater number of ships to maintain a weekly service frequency. This research exhibits robust timeliness and practicality, which is in line with practice. It not only timely supplements and enhances the extant body of knowledge concerning SECAs but also serves as a valuable point of reference and emulation for shipping companies seeking to optimize their operations within the framework of the new policy landscape. Furthermore, it offers pertinent insights for the IMO in formulating policies related to SECAs.

In-situ Formation of Sulphur-Trapped Petroleum Coke via Thermal Cracking of Vacuum Residue: A Practical Approach to Reduce Environmental Pollution

Environmental regulations restrict the use of high-sulphur petroleum coke as a solid fuel due to the emission of a substantial amount of sulphur oxides (SOx) upon combustion. Therefore, the free sulphur present in petroleum coke needs to be reduced to achieve lower SOx emissions. This paper describes a novel and efficient method for the trapping of free sulphur in petroleum coke during its formation from vacuum residue in the presence of an additive. Among the various additives tested, calcium oxide (10 wt%) was found to be most effective for maximum trapping of free sulphur in petroleum coke. This sulphur-trapped petroleum coke reduces SO2 emissions by 67% upon combustion; hence, it can be used as a better fuel than regular high-sulphur petroleum coke. Thus, by replacing regular petroleum coke with this newly developed sulphur-trapped petroleum coke, environmental pollution can be reduced significantly.

Economic incentives and technological limitations govern environmental impact of LNG feeder vessels

In the transition to sustainable shipping, Liquified Natural Gas (LNG), is proposed to play a role, reducing emissions of sulphur and nitrogen oxides, and particulate matter. However, LNG is a fossil fuel and there is an ongoing discussion regarding the extent of methane slip from ships operating on LNG, challenging the assumptions of LNG as a sustainable solution. Here we show another aspect to consider in the environmental assessment of shipping; LNG feeder vessels may spend as much as 25% of their time at sea just running the ship to ensure the pressure in the tanks are not exceeded, i.e., run time not directly attributed to the shipment of gas from one port or ship, to another. In other words, the economic incentives are currently allowing for roughly 32% increase of the ships’ operational emissions and discharges and increased navigational risks. Most coastal areas are heavily affected by anthropogenic activities and e.g., in the Baltic Sea there is consensus among the HELCOM member states that the input of nutrient and hazardous substances must be reduced. Even if the LNG feeder vessels are currently few, the possibility to reduce their environmental impact by 32% should be an attractive opportunity for future policy measures and investigation of technological solutions of the problem.