Search Results (160)

This study presents the techno-economic optimization of a hybrid distillation-membrane process for the complete fractionation of liquefied petroleum gas (LPG), targeting high-purity propane, n-butane, and isobutane recovery. The process employs an initial distillation column to separate propane (99% purity) from a propane-enriched stream, which is subsequently fed to a two-stage membrane system using an MFI zeolite hollow-fiber membrane for n-butane/isobutane separation. Through systematic simulation and sensitivity analysis, different membrane configurations were evaluated. The two-stage process with a partial residue-side reflux configuration demonstrated superior economic performance, achieving a total operating cost of 31.58 USD/h. Key membrane parameters—area, permeance, and separation factor—were optimized to balance separation efficiency with energy consumption and cost. The analysis identified an optimal configuration: a membrane area of 800 m², an n-butane permeance of 0.9 kg·m⁻²·h⁻¹, and a separation factor of 40. This setup ensured high n-alkane recovery while effectively minimizing energy use and capital investment. The study concludes that the optimized distillation-membrane hybrid process offers a highly efficient and economically viable strategy for the full utilization of LPG components. Full article

This project presents the design and implementation of an IoT-based system for early detection of Liquefied Petroleum Gas (LPG) leaks in residential environments. Three functional prototypes were developed, integrating gas sensors, microcontrollers, actuators, and wireless modules. The system achieved 89.48% service availability and response times under 2 s from leak detection to data storage and visualization. Operating under a distributed architecture, it enables continuous monitoring, automatic shut-off, and real-time alerts. The novelty lies in the applied integration of electronics, embedded systems, and automation into an affordable, replicable solution, that enhances household safety, promotes preventive behavior, and supports the adoption of affordable, replicable technologies in vulnerable domestic settings. Full article

Liquefied petroleum gas (LPG), composed mainly of propane and butane, is widely used as an energy source in residential, commercial, and industrial sectors; however, its high flammability poses a critical risk in the event of accidental leaks. In Peru, where LPG constitutes the main domestic energy source, leakage emergencies affect thousands of households each year. This pattern is replicated in developing countries with limited energy infrastructure. Early quantitative detection of propane, the predominant component of Peruvian LPG (~60%), is essential to prevent explosions, poisoning, and greenhouse gas emissions that hinder climate change mitigation strategies. This study presents PropNet-R, a convolutional neural network (CNN) designed to estimate propane concentrations (ppm) from thermal images. A dataset of 3574 thermal images synchronized with concentration measurements was collected under controlled conditions. PropNet-R, composed of four progressive convolutional blocks, was compared with SqueezeNet, VGG19, and ResNet50, all fine-tuned for regression tasks. On the test set, PropNet-R achieved MSE = 0.240, R² = 0.614, MAE = 0.333, and Pearson’s r = 0.786, outperforming SqueezeNet (MSE = 0.374, R² = 0.397), VGG19 (MSE = 0.447, R² = 0.280), and ResNet50 (MSE = 0.474, R² = 0.236). These findings provide empirical evidence that task-specific CNN architectures outperform generic transfer learning models in thermal image-based regression. By enabling continuous and quantitative monitoring of gas leaks, PropNet-R enhances safety in industrial and urban environments, complementing conventional chemical sensors. The proposed model contributes to the development of sustainable infrastructure by reducing gas-related risks, promoting energy security, and strengthening resilient, safe, and environmentally responsible urban systems. Full article

This study investigates the energy and environmental implications of replacing E10 gasoline with Liquefied Petroleum Gas (LPG) in a Euro 4 passenger car under real-world urban driving conditions. A comparative methodology robust to operating-state distribution was applied, combining portable exhaust gas analysis with on-board diagnostic data to calculate energy-specific emissions per crankshaft revolution and to reconstruct emission surfaces in the load–RPM domain using bilinear interpolation. The study revealed that LPG reduces carbon dioxide emissions by 8.35%, demonstrating a clear climate and energy benefit due to its lower carbon intensity. In comparison, carbon monoxide (+9.5%) and hydrocarbons (+8.3%) increased under low-load and idle conditions. Nitrogen oxides showed only minor differences between the fuels (+1.3%). LPG exhibited a more stable CO₂ emission profile, reflecting improved combustion efficiency from an energy perspective, although its performance in terms of incomplete combustion products requires further optimisation. The methodology highlights how linking energy efficiency with pollutant formation provides a comprehensive framework for evaluating alternative fuels in Real Driving Emissions (RDE) tests. The results confirm LPG’s potential to reduce greenhouse gas emissions in transport systems and identify calibration strategies needed to mitigate trade-offs in local pollutant emissions. Full article

Consumption of meat singed with non-standard fuels is a common practice in many low- and middle-income settings, yet it may introduce combustion-derived toxicants with serious health consequences. While the toxicological effects of pollutants such as polycyclic aromatic hydrocarbons and heavy metals are well documented, the specific impact of singed meat consumption on endocrine regulation remains poorly understood. Of particular concern is the reproductive hormonal network, which not only serves as a sensitive biomarker of systemic disruption but also represents an evolutionary safeguard of fertility and generational continuity. Our study addresses this knowledge gap using male Wistar rats fed for 90 days (week 0 to week 12) on diets containing increasing proportions (25%, 50%, 75%) of meat singed with firewood, liquefied petroleum gas (LPG), or tyres. Firewood- and tyre-singed meat induced dose- and source-dependent toxicity, including hepatocellular injury, impaired protein metabolism, elevated blood urea nitrogen and creatinine, organ hypertrophy, and pronounced oxidative stress. Hormonal analysis revealed reduced testosterone alongside increased FSH, LH, and prolactin, indicating hypothalamic–pituitary–gonadal axis disruption and reproductive risk. In contrast, LPG-singed meat caused only minor alterations. These findings highlight reproductive hormones as sensitive biomarkers, underscoring the health risks of singeing practices and their evolutionary implications for fertility and population fitness. Full article

There is still a need to develop scenarios and models aimed at substituting fuelwood and reducing the use of fossil fuels such as liquefied petroleum gas (LPG), on which low-income rural households in the Global South often depend. The use of these fuels for cooking and heating in domestic and productive activities poses significant health and environmental risks. This study validated, in three different phases, the sustainability of a model for the production and use of biogas from the treatment of swine-rearing wastewater (WWs) on a community farm: (i) A Multi-Criteria Analysis (MCA), incorporating environmental, social/health, technical, and economic criteria, identified the main weighted criterion to C8 (use of small-scale technologies and low-cost access), with a score of 0.44 points, as well as the Tubular biodigester (Tb) as the most suitable option for the study area, scoring 8.1 points. (ii) Monitoring of the Tb over 90 days showed an average biogas production of 2.6 m³ d⁻¹, with average correlation 0.21 m³ Biogas kg Biomass⁻¹. Using the experimental biogas production rate (k = 0.0512 d⁻¹), the process was simulated with the BgMod model, achieving an average deviation of only 10.4% during the final production phase. (iii) The quantification of benefits demonstrated significant reductions in firewood use: in Scenario S1 (kitchen energy needs), biogas replaced 83.1% of firewood, while in Scenario S2 (citronella essential oil production), the substitution rate was 24.1%. In both cases, the avoided emissions amounted to 0.52 tons of CO_2eq per month. Finally, this study proposes a synthesised, community-based rural biogas framework designed for replication in regions with similar socio-environmental, technical, and economic conditions. Full article

Natural vaporization in LPG (liquefied petroleum gas) tanks refers to the process where liquid LPG is converted to vapor naturally due to ambient heat. This natural vaporization process relies on ambient heat from the surroundings, which is transferred through the walls of the LPG tank. The natural vaporization rate depends on several factors, such as the ambient temperature, the surface area of the tank in contact with the liquid (i.e., the filling fraction), the exact composition of LPG, and the design and positioning of the LPG tank. When natural vaporization rates cannot meet the gas demand, as in the case of colder climates and large commercial applications, an additional LPG vaporizer will be necessary. The obtained results revealed that pure propane at an operating pressure of 1.75 bar achieves specific vaporization rates per unit of tank surface area of 0.7 kg/h/m², which decreases to 0.4 and 0.25 kg/h/m² for LPG mixtures with 20% and 40% butane, respectively. For a lower operating pressure of 1.10 bar, the specific vaporization rate per unit of tank surface area is 1.0 kg/h/m² for pure propane, 0.85 kg/h/m² for 20% butane, and 0.70 kg/h/m² for 40% butane. Full article

Countries worldwide are focused on the objective of zero emissions by 2050. However, the accelerated implementation of clean technologies has had some drawbacks, remarkably those related to safety issues. Liquefied petroleum gas (LPG) emerges as a transition fuel in this context, considering the following two aspects. First, LPG is a fuel that has environmental advantages compared to other fossil fuels, so the extension of coverage as a replacement fuel is a key factor. Second, LPG has a well-developed storage and transportation infrastructure that can be used, sometimes without modifications, for clean fuels, helping their implementation. Therefore, the safety analysis and the study of the consequences related to the hazards of LPG is a current subject that contributes, through all the tools reviewed in this article, to not only reduce the risks of this fuel but also to connect with the safety issues of clean fuels. This review article provides a comprehensive overview through consequence modeling tools, highlighting computational fluid dynamics (CFD) and machine learning to pave the way for the full implementation of clean fuels that will power the future of humanity. Full article

With the extensive use of liquefied petroleum gas (LPG) in the catering industry, leakage explosions have become frequent. This study employs numerical simulations to investigate the diffusion patterns of LPG leakage under various ventilation conditions. The results show that there is a logarithmic relationship between the wind speed and the volume of a propane gas cloud under natural ventilation. In the wind speed ranges of 1.5 to 3.3 m/s and 7.9 to 10.7 m/s, a small increase in wind speed leads to a significant reduction in gas cloud volume (97.2% and 95.05%, respectively). Under forced ventilation, the volume of the gas cloud decreases by 90.6%, from 6.67 m³ at higher air exchange rates (22.1 and 24.3 times/h), reducing explosion risks. When leakage occurs at the stove, the optimal combination for dispersing the propane combustible gas cloud is window opening at position 1 and fan at position a. The volume of the gas cloud at window position 1 increases exponentially with the distance between the fan and the leak source. The fan is installed within 2.786 m from the leak source to ensure that the gas cloud volume remains below 0.5 m³. These findings provide valuable insights for the design and the optimization of ventilation systems and layouts in commercial kitchens. Full article

Recently, the IMO has completed the guidelines on the life cycle greenhouse gas intensity of marine fuels to accelerate the application of alternative fuels. Low-carbon fuels may persist for decades and have become a key transitional phase in replacing marine fuels. A more comprehensive methodology for evaluating the carbon emission levels of marine fuels was explored, and the carbon emissions and environmental impacts of a 150,000-ton shuttle tanker under 19 dual-fuel power scenarios were evaluated using the Energy Efficiency Design Index (EEDI) and life cycle assessment (LCA) method. The results show that liquefied natural gas (LNG) has a higher carbon control potential level compared to liquefied petroleum gas (LPG) and methanol (MeOH), while LPG is superior to MeOH based on EEDI evaluation. LCA analysis results show that MeOH (biomass) has the best carbon control potential considering the carbon emissions of the well-to-tank phase of the fuel, followed by LNG, LPG, MeOH (natural gas, NG), and MeOH (coal). However, MeOH (NG) and MeOH (coal) had greater negative environmental impacts. This study provides method support and a direction toward improvement for revising related technical specifications and regulations for dual-fuel vessel performance evaluation, considering the limitations of various maritime regulations. Full article

As a major contributor to industrial energy consumption and carbon emissions, the kiln industry faces increasing pressure to adopt cleaner energy sources. This study investigated the combustion characteristics, redox processes in celadon firing, product quality, and pollutant emissions for an industry furnace with methanol and liquefied petroleum gas (LPG) as kiln fuels. Methanol combustion reduced firing time by 17.4% due to the faster temperature rise during oxidation and holding phases and provided a more uniform and stable flame, compared with LPG cases. Significant reductions in emissions were observed when methanol is used as fuel. For example, NO concentration is reduced by 70.89%, 37.43% for SO₂, 93.67% for CO, 45.07% for CO₂, and 85.89% for CH₄. The methanol-fired celadon exhibited better quality in terms of the appearance and threshold stress–strain value. The chemical analysis results show that K/O element ratio increased from 8.439% to 11.706%, Fe/O decreased from 4.793% to 3.735%, Al/O decreased from 33.445% to 31.696%, and Si/O increased from 76.169% to 89.825%. These findings demonstrate the potential of methanol as a sustainable kiln fuel, offering enhanced combustion efficiency, reduced emissions, and improved ceramic quality. Full article

To address the issue of volatile organic compound (VOC) emissions during crude oil storage and transportation, this study proposes a sandwich-structured zeolite molecular sieve (SMZ) fabricated via a pressing-sintering process integrating ZSM-5 powder and granules. The resulting monolithic zeolite exhibits enhanced mechanical strength and optimized pore architecture. Systematic investigations revealed that sintering at 600 °C with 10% carboxymethyl cellulose (CMC) yielded SMZ with a specific surface area of 349.51 m²/g and pore volume of 0.37 cm³/g. Its hierarchical pore system—micropores (0.495 nm) coupled with mesopores (2–10 nm)—significantly improved adsorption kinetics. Dynamic adsorption tests demonstrated superior performance: SMZ achieved saturation capacities of 127.6 mg/g for propane and 118.2 mg/g for n-butane in liquefied petroleum gas (LPG), with a breakthrough time of 41 min and a 106% increase in adsorption capacity compared to conventional monolithic zeolite (MZ) (90.2 mg/g vs. 43.8 mg/g). Regeneration studies confirmed that combined thermal desorption (250 °C) and nitrogen purging maintained > 95% capacity retention over five cycles, attributed to the high thermal stability of the MFI topology framework (≤600 °C) and crack-resistant ceramic-like interfaces. Additionally, SMZ exhibited exceptional hydrophobicity, with a selectivity coefficient of 20.9 for propane under 60% relative humidity. This work provides theoretical and technical foundations for developing efficient and durable adsorbents for industrial VOC mitigation. Full article

Natural and liquefied petroleum gases are widely used in industrial heat treatment. However, the rising cost of gas, combined with increased demand, has significantly impacted production costs and the environment. The annealing process typically relies on natural or liquefied petroleum gases as the primary heat source. In this study, we aimed to investigate the use of biomass fuel as a replacement for fossil fuels and to evaluate the mechanical properties and microstructure of wire rod steel after annealing using indirect heat from a gasifier. We experimented to examine the effects of annealing temperatures of 650 °C, 700 °C (below the critical temperature Ac1), and 750 °C (above Ac1 but below the upper temperature Ac3). The batch furnace, made of stainless steel, was modified from a traditional wire annealing furnace that originally used CNG and LPG gas burners. It was adapted into a wire annealing furnace connected to a cross-draft gasifier. The furnace’s interior was designed with spiral cooling fins to minimize energy consumption and shorten annealing time. Additionally, it was modified to use biomass as a substitute fuel, reducing environmental pollution. The furnace was coated with thermal insulation, and the biomass gasifier stove was a cross-draft device with primary air feeding at 20 m³/h and secondary air supplied at a constant flow rate of 32 m³/h, 36 m³/h, or 40 m³/h. As a fuel source, we used eucalyptus. The mechanical properties of wire rod steel were measured in terms of tensile strength and torsion, following the TIS 138-2562 standard. This standard specifies that the tensile strength must be at least 260 MPa. Regarding torsion, the TIS 138-2562 requirements state that the wire must withstand at least 75 rounds of twisting without breaking. Our results showed that after annealing at 650 °C, 700 °C, or 750 °C, with a soaking time of 30 min and subsequent cooling in the furnace at natural temperature for 24 h, the tensile strength values were 494.82, 430.87, and 381.33 MPa, respectively. The torsion values were 126.92, 125.8, and 125.76 rounds, respectively. Additionally, ferrite grain size increased with annealing temperature, reaching a maximum of 750 °C. The total annealing duration for each batch was 2 h and 40 min at 650 °C, 2 h and 10 min at 700 °C, and 2 h at 750 °C. Full article

LGP cylinders are necessary for fuel storage and home heating. To avoid material and human risk, it is essential to maintain their structural integrity. Extensive mechanical research studies and physical tests are necessary for its design. This paper investigates the mechanical performance of the storage capacity of an LPG cylinder under static loading. The authors integrate and adapt IGA with the T-Splines function for geometry modeling and numerical analysis in the context of linear elasticity. The main focus is on the strains and stress numerical results. The obtained results are examined and verified with the FEM in Abaqus/Standard. The results found show that the storage capacity of a single cylinder is equivalent to 15 empty cylinders. This study also demonstrates that the T-Splines method is a promising alternative for numerically analyzing the mechanical structure performance of LPG cylinders, particularly in energy storage issues. Full article

The increasing requirement for distillates, accompanied by higher quantities of heavy crude oil in world production, has positioned gas oil hydrocracking as one of the most significant processes in refineries. In the petrochemical industry, hydrocracking is an essential process that converts heavy hydrocarbons into lighter and more valuable products such as LPG (liquefied petroleum gas), diesel, kerosene, light naphtha, and heavy naphtha. This method uses hydrogen and a catalyst to break down the gas oil feedstock through hydrogenation and hydrocracking reactions. However, the gas oil hydrocracking process faces significant technical, economic, and financial obstacles that must be overcome to reveal its full potential. In this study, a computer-assisted technical–economic evaluation and an evaluation of the technical–economic resilience of the gas oil hydrocracking process at an industrial scale was carried out. Twelve technical–economic and three financial indicators were evaluated to identify this type of process’s current commercial status and to analyze possible economic performance parameter optimizations. The economic indicators listed include gross profit (GP), profitability after taxes (PAT), economic potential (EP), cumulative cash flow (CCF), payback period (PBP), depreciable payback period (DPBP), return on investment (ROI), internal rate of return (IRR), net present value (NPV), annual cost/revenues (ACR), break-even point (BEP), and on-stream efficiency at the BEP. On the other hand, the financial indicators proposed by the methodology are earnings before taxes (EBT), earnings before interest and taxes (EBIT), and earnings before interest, taxes, depreciation, and amortization (EBITDA). The technical–economic resilience of the process was also evaluated, considering the costs of raw materials, the market prices of the products, and processing capacity. The gas oil hydrocracking plant described, with a useful life of 20 years and a processing capacity of 1,937,247.91 tonnes per year, achieved a gross profit (GP) of USD 58.97 million and a return after tax (PAT) of USD 39.77 million for the first year, operating at maximum capacity. The results indicated that the process is attractive under a commercial approach, presenting a net present value (NPV) of USD 68.87 million at the end of the last year of operation and a cumulative cash flow (CCF) of less than one year⁻¹ (0.34 years⁻¹) for the first year at full processing capacity, which shows that in this process, variable costs have more weight on the economic indicators than fixed costs. Full article