Two-time Calibration at Both Ends for Sulfur Measurement by Using High Frequency Induction Infrared Absorption Method

High frequency induction heating infrared absorption method is a relative measurement method, and it requires calibrating the analyzer during the measurement process. Usually, one-time calibration on an analyzer is made for high sulfur value by using standard substances. The method proposed by this paper calibrates carbon-sulfur analyzers with a method of two-time calibration at both ends, which eliminates the impact of sulfur blank and thus improves the accuracy and precision of ultra-low sulfur measurement. The method extents the lower limit of measurement of sulfur in high temperature alloy, to 0.00005%, namely, 0.5ppm.

High Sulfur in Primitive Arc Magmas, Its Origin and Implications

Sulfur contents in 98.5% of melt inclusions (MI) from calc-alkaline subduction basalts do not exceed 4000 ppm, whereas experimentally established limits of sulfur solubility in basaltic melts with high fO2 (characteristic of subduction zones, e.g., QFM + 2) surpass 14,000 ppm. Here we show that primitive (Mg# 62-64) subduction melts may contain high sulfur, approaching the experimental limit of sulfur solubility. Up to 11,700 ppm S was measured in olivine-hosted MI from primitive arc basalt from the 1941 eruption of the Tolbachik volcano, Kamchatka. These MI often contain magmatic sulfide globules (occasionally enriched in Cu, Ni, and platinum-group elements) and anhydrite enclosed within a brown, oxidized glass. We conclude that the ubiquitous low sulfur contents in MI may originate either from insufficient availability of sulfur in the magma generation zone or early magma degassing prior to inclusion entrapment. Our findings extend the measured range of sulfur concentrations in primitive calc-alkaline basaltic melts and demonstrate that no fundamental limit of 4000 ppm S exists for relatively oxidized subduction basalts, where the maximum sulfur content may approach the solubility limit determined by crystallization of magmatic anhydrite.

Strategies for the Low Sulfur Policy of IMO—An Example of a Container Vessel Sailing through a European Route

Ships are an important part in international trade transportation and a major source of pollution. Therefore, the International Maritime Organization (IMO) implemented an amendment to the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex VI, which stipulates that the sulfur content in marine fuel oil shall not exceed 0.5 wt.% starting in 2020. In order to meet the IMO low sulfur policy, shipping lines could adopt one of the following strategies: (1) using very low sulfur fuel oil (VLSFO), i.e., with sulfur content less than 0.5 wt.%; (2) installing scrubbers or other exhaust gas aftertreatment systems; or (3) replacing current fuels with clean alternative fuels such as natural gas. This study evaluates the feasibility and benefits of these strategies for shipping lines in order to determine the most cost-effective measures. First, according to the feasibility of the strategies evaluated by SWOT analysis, although scrubbers can reduce emissions of sulfur oxides into the atmosphere, more and more countries are restricting the discharge of wastewater from open-loop scrubbers into their waters. Instead, VLSFO and liquefied natural gas (LNG) are good choices in terms of environmental protection and economic benefits. Therefore, this study further evaluates the two strategies of replacing high sulfur fuel oil (HSFO) with VLSFO and converting diesel engines to LNG engines based on a cost-benefit methodology. This study took an 8500 TEU container vessel, which is powered by a marine diesel engine with the nominal power of 61,800 kW, sailing the Asian-European route as an example, and calculated the total incremental costs, pollutant emission reductions, and cost benefits arising from the implementation of the VLSFO and LNG strategies, respectively. According to the results of this study, the total incremental cost of LNG is higher than that of VLSFO in the first 4.7 years, but this gradually decreases, making the gap of the total incremental costs between the two strategies wider year by year. In comparison with using HSFO without any improvement, the total incremental costs of the VLSFO and LNG strategies increase by 12.94% and 22.16% over the following five years, respectively. The use of LNG can significantly reduce SOx, PM, NOx, and CO2 emissions; on the other hand, it leads to more CH4 emissions than the VLSFO strategy. Compared to doing nothing, the cumulative reduction rates of SOx, PM, NOx, and CO2 emissions over the next five years after the adoption of the LNG strategy are 3.6%, 7.0%, 70.4%, and 15.7%, respectively. The higher emission reduction rates of LNG compared to VLSFO illustrate that the former has a good effect on the suppression of exhaust gas pollution. In terms of the cost-benefit evaluation of the two strategies, this study shows that the VLSFO strategy is more cost-effective than the LNG strategy in the first 2.5 years, but that the cost-benefit ratio of the latter increases year by year and exceeds that of the former, and the gap between them widens year by year. Based on the evaluation results of this study, the LNG strategy is suitable for ocean-going container vessels with fixed routes and younger or larger sized vessels to meet the IMO low sulfur policy. In contrast, the VLSFO strategy is appropriate for old merchant ships with fewer container spaces. LNG is a suitable medium- and long-term strategy, i.e., for more than 2.5 years, for shipping lines to meet the IMO low sulfur policy, while VLSFO is a suitable short-term strategy.

DAMPAK IMPLEMENTASI GREEN SHIPPING PADA PERUSAHAAN PELAYARAN

Penelitian ini bertujuan untuk mengevaluasi implementasi Green Shipping pada industri Perkapalan dan Transportasi Laut Kalimantan Timur yang sesuai aturan International Maritime Organization yang dimuat dalam Marine Pollution Regulasi Annex VI. Data yang digunakan dalam penelitian ini adalah data sekunder berupa data spesifikasi kapal TB. Rezky 27. Alat analisis yang digunakan dalam penelitian ini adalah analisis kuantitatif yaitu mengolah data perhitungan jumlah konsumsi bahan bakar, menghitung faktor emisi, simulasi perhitungan penggunaan bahan bakar dan membandingkan biaya konsumsi bahan bakar. Hasil penelitian menemukan bahwa berdasarkan perhitungan konsumsi lima bahan bakar yang dapat digunakan kapal, bahan bakar LNG memiliki biaya konsumsi paling kecil dibanding bahan bakar lainnya namun ketersediaan LNG sebagai bahan bakar alternatif masih kurang untuk memenuhi kebutuhan industri pelayaran selanjutnya biaya konsumsi bahan bakar Solar dan HSFO (High Sulfur Fuel Oil) memiliki biaya yang kecil namun mengharuskan kapal menggunakan scrubber sehingga berdampak pada perusahaan pelayaran yang harus mengeluarkan biaya investasi untuk pembelian Scrubber. Penggunaan bahan bakar methanol sebagai bahan bakar alternatif karena ramah lingkungan dapat digunakan di industri pelayaran namun diperlukan modifikasi dan penyesuaian pada mesin kapal sehingga berdampak pada biaya yang harus ditanggung oleh perusahaan. Penggunaan bahan bakar LSFO (Low Sulfur Fuel Oil) berdasarkan perhitungan konsumsi bahan bakar memiliki biaya yang paling tinggi diantara bahan bakar lainnya namun bahan bakar ini adalah bahan bakar yang sesuai dengan aturan IMO.

Сhanging the lubricity of diesel fuel with vegetable oil additive

Intriduction. The environmental safety of cars with a diesel engine does not lose its relevance. In the conditions of stricter requirements for diesel fuel, the content of many substances harmful to the environment, including sulfur, is not allowed. As is known, low-sulfur fuels require the presence of additives that improve the lubricating properties of diesel fuel. Non-compliance with the requirements for lubricity significantly affects the resource of the fuel supply system of a diesel engine, primarily the Common Rail system. In order with the circumstances listed above, we hypothesized that vegetable oil can serve in small concentrations to improve the lubricating properties of fuels.Materials and methods. In our research, we conducted experiments using the standard HFRR method (highfrequency translational motion of a ball rubbing against a plate in fuel). A microscope was used to visually assess the wear spots and measure their size. Diesel fuel was taken as samples for experiments and vegetable oil was added to it as an additive in certain proportions.Discussion and conclusions. The vegetable oil additive can improve the lubricity of diesel fuel, even if it does not comply with GOST for this parameter. The experiments conducted allow us to conclude that the vegetable oil additive as a percentage of diesel fuel almost linearly reduces the diameter of the wear spot

A Fe3N/carbon composite electrocatalyst for effective polysulfides regulation in room-temperature Na-S batteries

The practical application of room-temperature Na-S batteries is hindered by the low sulfur utilization, inadequate rate capability and poor cycling performance. To circumvent these issues, here, we propose an electrocatalyst composite material comprising of N-doped nanocarbon and Fe3N. The multilayered porous network of the carbon accommodates large amounts of sulfur, decreases the detrimental effect of volume expansion, and stabilizes the electrodes structure during cycling. Experimental and theoretical results testify the Fe3N affinity to sodium polysulfides via Na-N and Fe-S bonds, leading to strong adsorption and fast dissociation of sodium polysulfides. With a sulfur content of 85 wt.%, the positive electrode tested at room-temperature in non-aqueous Na metal coin cell configuration delivers a reversible capacity of about 1165 mA h g−1 at 167.5 mA g−1, satisfactory rate capability and stable capacity of about 696 mA h g−1 for 2800 cycles at 8375 mA g−1.

Distribution of sulfides and PGE minerals in the picritic and taxitic gabbro-dolerites of the Norilsk 1 intrusion

ABSTRACT Disseminated ores in the Norilsk 1 intrusion were studied to elucidate the typomorphic features of sulfides and noble metal mineralizations in picritic and taxitic (or lower olivine) gabbro-dolerites. The former are characterized by the development of a low-sulfur sulfide association (troilite, Fe-rich pentlandite, talnakhite, chalcocite, native copper) while the latter exhibits a high-sulfur association (monoclinic pyrrhotite, Ni-rich pentlandite, pyrite, heazlewoodite). The contact between these types of rocks is geochemically and mineralogically contrasting. The mineralogical and geochemical zoning directed from the roof to the base of each layer is expressed by an increase in the Cu content (and chalcopyrite) in ores, an increase in the concentration of Ni in pentlandite and S in pyrrhotite in line with a decrease of the crystallization temperature, and an increase in sulfur fugacity in the same direction. Zoning of Pd(Pt) mineralization in picritic and taxitic (olivine) gabbro-dolerites is uniform and characterized by the distribution of Pd-Sn compounds in the upper parts (together with Pd-Pb minerals in picritic rocks) and Pd-As compounds in the lower parts of the sections according to a drop in temperature. Such reverse zoning contradicts the typical mechanism of differentiation by fractional crystallization, and possibly suggests a fluid-magmatic nature. Mineralogical and geochemical features in platinum group element-Cu-Ni-bearing rocks are consistent with the idea that different stages of multi-pulse intrusions of mafic-ultramafic magmas with different compositions formed the picritic and taxitic gabbro-dolerites of the Norilsk region.

The Alternating Growth of Bacteria within a Consortium During Desulfurization of Coal

Efforts to reduce organic sulfur in coal are taken through biodesulfurization by using desulfurization bacteria to release covalently-bound sulfur from the coal matrix. Coal is a complex hydrocarbon material that requires collaboration from more than one type of bacteria in a consortium for desulfurization. The current study shows how the individual members of a bacterial consortium obtained directly from coal samples grew on the coal. Mineral medium containing sub-bituminous coal with a concentration of 10%, 15%, and 20% served as a carbon source and the only sulfur to support the consortium's growth. The examination included growth patterns, concentrations of dibenzothiophene as an organic sulfur representative, pH, and sulfate concentration as the sulfur product released into the medium. The growth of individual members of the consortium was observed for 336 h. The consortium grew in all three coal concentrations with slightly different cell growth patterns and the release of dibenzothiophene. Members of the consortium grew alternately and overlapped, which showed possible linkages or dependence on products and existence from the growth of other members. The existence of the primary strain Moraxella osloensis COK1 indicated that they played a role in the activities and growth of other members. The alternating growth is discussed to produce a hypothetical illustration of how several other members play in using sulfur in a well-known desulfurization pathway. In conclusion, this study provides a deeper insight into the value of consortium members individually but growing together while swarming coal as a complex resource to become low-sulfur coal.