ABSTRACT This study proposes a novel integrated system (SDKC‐DORC) that combines a split‐flow dual‐pressure Kalina cycle with a secondary organic Rankine cycle for the synergistic utilization of solar energy and liquefied natural gas (LNG) cold energy. The system performance is simulated in Aspen HYSYS, and a parametric analysis is conducted to evaluate the effects of four key variables: the evaporation temperature ( t 8 ), the mass flow rate of the second‐stage ORC ( q m,35 ), the split ratio ( x 5 ), and the inlet pressure of Turbine 4 ( P 50 ). The proposed integrated system, which harnesses solar energy and LNG through a novel combination of dual‐pressure Kalina and organic Rankine cycles, emerges as a pivotal strategy for low‐grade thermal energy utilization, demonstrating exceptional performance. Multiobjective optimization results indicate that the SDKC‐DORC configuration achieves optimal energy efficiency, electrical efficiency, and unit product cost of 65.82%, 60.26%, and 20.05$/GJ, respectively. A comparative analysis further reveals its superior thermodynamic and economic performance over the dual‐pressure Kalina two‐stage organic Rankine cycle (DKC‐DORC). Under identical operating conditions, the SDKC‐DORC system exhibits enhancements of 271.51 kW in net power output, 21.64% in energy efficiency, 10.63% in electrical efficiency, and 6.66% in cold recovery rate. Economically, it also presents a substantially higher annual net asset value, exceeding that of the DKC‐DORC system by $3.06 × 10 5 .

ABSTRACT This study presents a comparative analysis of two optimization approaches: Sequential Iterative Optimization (SIO) and Non‐dominated Sorting Genetic Algorithm II (NSGA‐II) applied to the separation of ternary mixtures (1‐butanol, isobutanol, and 2‐butanol) using Dual‐Column Distillation (DCD) and Dividing‐Wall Column (DWC) processes. Through a multi‐objective assessment considering total annual cost (TAC), CO 2 emissions, and entropy generation, the NSGA‐II optimized DCD and DWC processes demonstrated significantly better performance than the SIO approach in terms of energy efficiency, environmental impact, and economic viability. After NSGA‐II optimization, the DWC process reduced TAC by 20.97%, CO 2 emissions by 45.58%, and entropy generation by 39.43% compared to the DCD process. These findings demonstrate DWC technology's dual superiority in enhancing separation efficiency while significantly reducing energy consumption, particularly when optimized with the NSGA‐II.

ABSTRACT During underground excavation, coal dust generation threatens miners' health and damages ecosystems. Its generation is directly influenced by cutting pick performance and inherent coal properties. This study investigates the effects of coal properties and cutting parameters on coal fragmentation characteristics from a mesoscopic perspective, elucidating the dust generation mechanism during coal cutting. The results demonstrate that after normalizing the elastic modulus, both the damage range and the crack count in coal samples exhibit a decreasing trend with increasing confining pressure and uniaxial compressive strength (UCS), while the proportion of tensile cracks continues to decline. Correspondingly, dust generation follows an identical decreasing trend under these conditions. As the attack angle increases, the internal damage range, the crack count, and dust generation of coal samples first decrease and then increase, whereas the proportion of tensile cracks initially rises before decreasing. With greater cutting depth and larger pick tip angles, the damage range, the crack count, and the dust generation progressively increase, while the proportion of tensile cracks gradually decreases. The variation patterns of cutting force and specific energy (SE) obtained through numerical simulation are largely consistent with laboratory experimental findings. This study thus provides crucial insights for reducing coal dust and enhancing safety through optimized cutting strategies.

ABSTRACT Water pollution by oil and organic substances causes serious problems that threaten the ecosystem. Superhydrophobic materials represent an effective solution for removing oil from water. The present paper investigates the development of a low‐cost, superhydrophobic composite for oil–water separation. The disc‐shaped composite was prepared by embedding Scots pine sawdust into a Perspex (PMMA) matrix through a simple and convenient procedure. Scanning electron microscopy (SEM) was used to analyze the surface morphology, while the water contact angle was measured using an optical tensiometer to evaluate its wettability. The composite discs were tested for the removal of diesel, engine oil, corn oil, olive oil, and n‐hexane under ambient conditions using a gravity‐driven separation process. Durability and stability were evaluated through tape‐stripping, sandpaper abrasion, and chemical stability tests. SEM images showed a rough and porous surface, which is key to trapping air and achieving the Cassie–Baxter state. The resulting composite discs showed superhydrophobicity with a water contact angle of 151.5° and oil separation efficiency of more than 90%. The composite remained robust throughout 20 cycles of use. A correlation was established to predict the separation rate for oil viscosities ranging from 0.401 to 63.2 cSt. Durability tests showed that the composite disc retained its superhydrophobic behavior even after 100 tape‐peeling cycles and exhibited high hydrophobicity for up to 10 abrasion cycles. The composite disc maintained its superhydrophobic properties within pH range from 2 to 10.1, confirming its chemical stability. These results suggest that the developed sawdust–Perspex composite is a highly effective, sustainable and environmentally friendly option for oil–water separation.

ABSTRACT Hybridization of two or more desalination processes has been identified as an attractive option for improved energy efficiency and recovery rate. To appropriately assess the performance enhancement of hybrid desalination systems, an integrated approach for energy, exergy, economic, and environmental investigations should be adopted. This study considers the energy, exergy, and economic analysis of integrated mechanical vapor compression (MVC) and membrane distillation (MD) processes. Various MVC–MD hybrid configurations have been proposed and modeled. Exergy analysis revealed the escalation of destroyed work as the operating brine temperature rises because of increasing demand for compression power. It is also found that the incorporation of MD reduces the exergy losses to 25.53 kW, which amounts to 38.5% enhancement, and increases exergy efficiency to 0.63, which sums to 23.5% improvement. The compressor unit is found to exhibit unbalanced exergy of 12.94 kW, which is equivalent to 51% of the total exergy losses. The MD and the distillate preheater units are found to be the least exergy destructive components as their corresponding exergy efficiency approaches 0.96 and 0.86, respectively. Economic analysis indicates that the optimal water production cost occurs when the operating brine temperature resides between 60°C and 70°C depending on the cost of electricity. The optimum condition can be extended to higher temperatures when a very low electricity tariff is used. For nominal value for the electricity tariff of $0.06/kWh, the levelized water cost approaches $2.12/m 3 at brine temperature of 60°C. Moreover, the specific water cost can be reduced to $1.95/m 3 when the MVC production capacity is upgraded to 8 kg/s (691.2 m 3 /day). This optimum also occurs at brine temperature 60°C, which is also promoted by the exergy analysis findings as irreversibility descends at low operating temperatures.

ABSTRACT Significant enhancement of mixing performance can be achieved by Dean vortices in spiral channels. In order to deeply explore the mixing mechanisms and variation laws in spiral micromixers, this work designed a spiral micromixer and adopted a combined method of experiments and numerical simulations to analyze the mixing performance and mechanisms of spiral micromixers, wavy micromixers, T‐shaped micromixers, and spiral micromixers with different half‐axis length ratios. The study reveals that within the range of Reynolds numbers ( Re ) from 1 to 200, the mixing performance of spiral micromixers is superior to that of the unfolded wavy micromixers and T‐shaped micromixers. For spiral micromixers, there exists an optimal half‐axis length ratio. When the half‐axis length ratio is 0.65 and the Reynolds number is between 50 and 175, the mixing index increases by 4.3% to 25%. This research provides a reference basis for the structural design of the micromixer.

ABSTRACT In Vietnam, traditional distilled rice alcohol is often produced at the household scale with limited sanitary conditions, leading to low yield, unstable, and moderate‐quality alcohol products. No‐cook or Simultaneous liquefaction, saccharification, and fermentation (SLSF) technology has shown to be very promising thanks to its advantages such as reducing the loss of sugar due to the heating process, osmotic stress on yeast cells, energy for cooking, and water for cooling. This study aimed to compare the technical and economic efficiencies between the no‐cook technology and the traditional technology for rice alcohol production at a household scale. The two processes were conducted with 60 kg of rice per batch to evaluate essential parameters such as fermentation efficiency, quality of the final distilled rice alcohol, fermentation time, labor, water, electricity consumption, and production cost. The ethanol yield of the no‐cook and traditional processes was 86.25% and 72.99% of the theoretical ethanol yield, respectively. The quality of the final alcohol produced by both technologies met the physicochemical and sensory requirements specified in the national standard. The production cost per liter of final alcohol produced by no‐cook technology was equivalent to 73.38% of that produced by traditional technology (0.726 vs. 0.983 USD, respectively). The results suggested that the no‐cook technology could be promising and an alternative to the traditional one to improve the quality but also the economic efficiency of alcohol produced at the household scale.

ABSTRACT As refineries process increasingly inferior crude oils, ammonium salt corrosion has intensified. Accurate prediction of ammonium salt crystallization temperatures and their influencing factors is therefore crucial for safe and stable operations. In this paper, based on the thermodynamic principle, the correlation mechanism between relative humidity and entropy–enthalpy change was innovatively constructed. A thermodynamic calculation method of ammonium chloride crystallization temperature was proposed and applied to assess the corrosion risk in the overhead reflux system of an atmospheric tower in a refinery. The results show that the proposed model, incorporating dual corrections for humidity and pressure, has a better prediction accuracy than existing models. Higher chlorine and nitrogen contents both elevate the crystallization temperature, whereas sulfur content has a negligible effect. As the water injection rate increases, the crystallization temperature will decrease due to the humidity effect. The inhibition effect of crystallization temperature decreases sharply when it exceeds 20 t/h. The crystallization temperature decreases by approximately 1°C per 1% increase in relative humidity.

ABSTRACT Heavy metals in municipal waste incineration fly ash are potentially harmful to the ecological environment and human health. To mitigate the hazards of fly ash, this study attempts to detoxify fly ash through organic acid washing pretreatment coupled with cement/sodium diethyldithiocarbamate (DDTC) solidification. The results indicate that increasing the concentration of organic acids enhances the leaching of Fe, Al, K, Na, and Ca; reduces the alkalinity of the fly ash; and weakens its acid buffering capacity. Regarding the impact on heavy metals, higher acid concentrations promote the migration of Cd, Cu, Ni, and Pb into the liquid phase and increase the proportion of unstable forms of heavy metals remaining in the fly ash. Among them, citric acid (CA) exhibits a stronger affinity for K, Na, Ca, Pb, and Cu compared to oxalic acid (OA). Furthermore, the analysis of cement combined with DDTC for stabilizing heavy metals in acid‐washed fly ash reveals that, compared to cement stabilization alone, the combination of cement and DDTC significantly improves the stability of heavy metals in the solidified matrix. The leaching concentrations of Cd, Pb, and Cu initially increase and then decrease with the number of leaching cycles, while Ni shows an opposite trend. The morphology and crystalline phase analysis of the fly ash before and after stabilization elucidate the mechanisms of heavy metal immobilization. This study provides valuable insights for the practical industrial disposal of fly ash concerning the control of heavy metals and alkalinity.