Search Results (6)

Aluminum powder is the most commonly used metal fuel in the industry of explosives and propellants. The research progress in preparation technology, reactivity and application of nano-aluminum in explosives and propellants is systematically reviewed in this paper. The preparation technology of nano-aluminum powder includes mechanical pulverization technology (such as the ball milling method and ultrasonic ablation method, etc.), evaporation condensation technology (such as the laser induction composite heating method, high-frequency induction method, arc method, pulsed laser ablation method, resistance heating condensation method, gas-phase pyrolysis method, wire explosion pulverization method, etc.), chemical reduction technology (such as the solid-phase reduction method, solution reduction method, etc.) and the ionic liquid electrodeposition method, each of which has its own advantages. Some new preparation methods have emerged, providing important reference value for the large-scale production of high-purity, high-quality nano-aluminum powder. The reactivity differences between nano-aluminum powder and micro-aluminum powder are compared in the thesis. It is clear that the reactivity of nano-aluminum powder is much higher than that of micro-aluminum powder in terms of ignition performance, combustion performance and reaction completeness, and it has a stronger influence on the detonation performance of mixed explosives and the combustion performance of propellants. Nano-aluminum powder is highly prone to oxidation, which seriously affects its application efficiency. In addition, when aluminum powder oxidizes or burns, a surface oxide layer will be formed, which hinders the continued reaction of internal aluminum powder. In addition, nano-aluminum powder may deteriorate the preparation process of explosives or propellants. To improve these shortcomings, appropriate coating or modification treatment is required. The application of nano-aluminum powder in mixed explosives can improve many properties of mixed explosives, such as detonation velocity, detonation heat, peak value of shock wave overpressure, etc. Applying nano-aluminum powder to propellants can significantly increase the burning rate and improve the properties of combustion products. It is pointed out that the high reactivity of nano-aluminum powder makes the preparation and storage of high-purity nano-aluminum powder extremely difficult. It is recommended to increase research on the preparation and storage technology of high-purity nano-aluminum powder. Full article

This paper discusses the use of additional ultrasonic fuel treatment technology to reduce sulfur oxide emissions from marine diesel exhaust gases. The research was conducted on a Bulk Carrier vessel with a deadweight of 64,710 tons with the main engine YMD MAN BW 6S50ME-C9.7 and three auxiliary diesel generators CMP-MAN 5L23/30H. The exhaust gases from all engines were treated for sulfur impurities using a scrubber system. It was stated that the combined use of the exhaust gas scrubber system and ultrasonic fuel treatment technology (compared to scrubber-only exhaust gas cleaning) results in a reduction in carbon dioxide CO₂ and sulfur dioxide SO₂ emissions, along with their ratio SO₂/CO₂. The additional ultrasonic fuel treatment technology has had the most significant effect on sulfur-containing components, leading to a substantial decrease in SO₂ emissions from exhaust gases. For various operating conditions of ship diesel engines, a reduction in CO₂ emissions of 2.9–7.5% and a reduction in SO₂ emissions of 9.3–33.1% were established. This achieved a reduction of 6.3 to 23.7% in the SO₂/CO₂ ratio, a critical parameter for evaluating the performance of the scrubber system in exhaust gas cleaning, as mandated by the provisions of Annex VI of MARPOL. The requirements of the international conventions MARPOL and SOLAS were adhered to during the experiments. Full article

Palm oil mill effluent (POME), a byproduct of palm oil processing, has substantial resource recovery potential. Its rich biodegradable content supports methane (CH₄) production via anaerobic digestion, enabling renewable energy generation. Additionally, the significant water content of POME can be reclaimed for use in boiler feed, irrigation, and drinking water. However, selecting appropriate technologies to recover valuable resources from POME is challenging, particularly for the purification and upgrading of biogas. Membrane technologies offer an effective approach for transforming POME treatment from an energy-intensive process into a resource recovery system, supporting the decarbonization of palm oil production and advancing global sustainability objectives. This technique is cost-effective and ecofriendly for biogas purification and water reclamation. For biogas purification and upgrading, membrane systems offer the lowest capital and operational costs at 5.654 USD/m³, compared to other technologies, such as 6.249 USD/m³ for water scrubbers and 6.999 USD/m³ for chemical absorbers. This review primarily explores the potential of membranes for gas purification from POME and examines their integration with other processes to develop advanced systems, such as ultrasonicated membrane anaerobic systems and membrane anaerobic systems, to enhance biogas production. In addition, water reclamation from POME is discussed, with ultrafiltration membranes emerging as the most promising candidates. Proton exchange membranes, such as Nafion, are used extensively in microbial fuel cells to improve electricity generation, and this is also summarized. Finally, challenges and future perspectives are highlighted, emphasizing the broader potential of membrane technology in POME wastewater resource recovery. Full article

Background: It would be impossible to imagine a country where cereals and their byproducts were not at the peak of foodstuff systems as a source of food, fertilizer, or for fiber and fuel production. Moreover, the production of cereal proteins (CPs) has recently attracted the scientific community’s interest due to the increasing demands for physical wellbeing and animal health. However, the nutritional and technological enhancements of CPs are needed to ameliorate their functional and structural properties. Ultrasonic technology is an emerging nonthermal method to change the functionality and conformational characteristics of CPs. Scope and approach: This article briefly discusses the effects of ultrasonication on the characteristics of CPs. The effects of ultrasonication on the solubility, emulsibility, foamability, surface-hydrophobicity, particle-size, conformational-structure, microstructural, enzymatic-hydrolysis, and digestive properties are summarized. Conclusions: The results demonstrate that ultrasonication could be used to enhance the characteristics of CPs. Proper ultrasonic treatment could improve functionalities such as solubility, emulsibility, and foamability, and is a good method for altering protein structures (including surface hydrophobicity, sulfhydryl and disulfide bonds, particle size, secondary and tertiary structures, and microstructure). In addition, ultrasonic treatment could effectively promote the enzymolytic efficiency of CPs. Furthermore, the in vitro digestibility was enhanced after suitable sonication treatment. Therefore, ultrasonication technology is a useful method to modify cereal protein functionality and structure for the food industry. Full article

Landfill leachate (LFL) treatment is a severe challenge due to its highly viscous nature and various complex pollutants. Leachate comprises various toxic pollutants, including inorganic macro/nano components, xenobiotics, dissolved organic matter, heavy metals, and microorganisms responsible for severe environmental pollution. Various treatment procedures are available to achieve better effluent quality levels; however, most of these treatments are nondestructive, so pollutants are merely transported from one phase to another, resulting in secondary contamination. Anaerobic digestion is a promising bioconversion technology for treating leachate while producing renewable, cleaner energy. Because of its high toxicity and low biodegradability, biological approaches necessitate employing other techniques to complement and support the primary process. In this regard, pretreatment technologies have recently attracted researchers’ interest in addressing leachate treatment concerns through anaerobic digestion. This review summarizes various LFL pretreatment methods, such as electrochemical, ultrasonic, alkaline, coagulation, nanofiltration, air stripping, adsorption, and photocatalysis, before the anaerobic digestion of leachate. The pretreatment could assist in converting biogas (carbon dioxide to methane) and residual volatile fatty acids to valuable chemicals and fuels and even straight to power generation. However, the selection of pretreatment is a vital step. The techno-economic analysis also suggested the high economic feasibility of integrated-anaerobic digestion. Therefore, with the incorporation of pretreatment and anaerobic digestion, the process could have high economic viability attributed to bioenergy production and cost savings through sustainable leachate management options. Full article

A logical-informational model of energy resource-efficient chemical technology for the utilization of hydrogen sulfide and low molecular alkanethiols, which are toxic and difficult to remove sulfur components of residual fuel (fuel oil), is proposed. Based on the IDEF1 methodology and existing knowledge about the technological processes of the demercaptanization of various hydrocarbon raw materials (oils, gas condensates), a scheme for the production of organic sulfur compounds from sulfur waste extracted from fuel oil has been modeled. For a sufficiently complete removal of hydrogen sulfide and low molecular weight alkanethiols, energy- and resource-saving stages of the technological process have been developed, which are implemented by ultrasonic and/or magnetic treatment of fuel oil. It is proposed to use the combined action of two alternative methods of processing fuel oil to increase the efficiency of cleaning fuel oil from sulfur components. For the first time, an approach has been developed to utilize unwanted sulfuric impurities contained in fuel oil by involving electric and microwave synthesis in green technological processes, to obtain practically useful organic sulfur compounds with biological activity. It is shown that the use of one-electron oxidant thiols and hydrogen sulfide in organic media leads to the synthesis of organic disulfides and elemental sulfur. Indirect (with the use of mediators) electrosynthesis contributes to the cyclic conduct of the technological process, an increase in efficiency and a decrease in energy consumption compared to the direct (on electrodes) initiation of sulfur components. Full article