Knowing the maximum radius of fire, explosion and emission of toxic gases, can play a very important role in the operationalization of urban passive defense requirements in order to reduce vulnerability in accidents. The main objective of this study is modeling the extent of explosion, ignition and gas leakage Consequences in cylinders containing 26.2-liters of liquid gas, with passive defense approach.
In this study, the effective factors on discharge and release of gases are described and ALOHA software has been used as one of the most suitable software for modeling the gas emissions of LPG (Liquefied Petroleum Gas) cylinders. Based on the modeling results, the emergency response program during gas leakage is presented.
When the gas leaks from LPG cylinder with 1-inch vent valve, the cylinder will be empty in one minute and the gas concentration will be 12600 ppm (60% LEL) and 2100 ppm (10% LEL) up to 11 meters and 35 meters from cylinder, respectively. In the case of vapor cloud explosion, the explosive wave pressure will be about 3.5 psi, up to 13 meters from the reservoir which may cause serious damage, and it will be equal to 1 psi, up to 25 meters from the cylinder which has strength of breaking the glass. In case of furious fire, fire flame with eight meters’ length is created, with thermal radiation of about 10 Kw/m2 and 5 Kw/m2 up to 10 meters and 12 meters from the cylinder, respectively which can cause second-degree burns. In the event of BELIEVE, a fireball will occur with a diameter of 14 meters within 2 seconds, with thermal radiation of about 10 Kw/m2 up to 53 meters from the cylinder.
The consequences of flaring and explosion of LPG gas, up to 35 meters from cylinder, are the most serious threat for human health, if gas leaks from a cylinder. Optimal positioning of gas cylinders will have an important role in limiting the harmful effects of hazardous emissions in military barracks.

The relife valve is a critical part of a device that has great importance to ensure security of related persons life and financial. Use this piece is necessary in the system with possibility of increasing the internal pressure of the system. One of these systems is gas tanks that is such as a mobile bomb and in case of malfunctioning of relife valve, in which place there is a possibility of explosion. In this study, evaluation of valve failure a portable LPG gas cylinder is performed. For this purpose, chemical analysis, metallography, mechanical properties, and in particular the fractography was done on The broken sample. The surface quality of the samples were examined by stereomicroscope and scanning electron microscopy. The results show the fatigue failure. in effect of loss of surface quality due to pitting of the of inappropriate machining. The main factors contributing to this phenomenon was detected reduction of surface quality due to pitting and improper machining.

In this study, validity and accuracy of the particle tracking method for estimating the distribution of recirculated gases between intake manifold runners have been investigated. For this purpose, several experiments have been performed on EF7-TC engine on various working conditions and with different rates of recirculated gas injection. The experimental method is designed based on the LPG gas injection and its effect on the amount of λ of each cylinder exhaust gases. Contribution of each cylinder of the injected gas is determined by performing a simple calculation on the measured values obtained from experiments. In addition the numerical results are calculated by using the boundary conditions derived from 1-D model which is calibrated with the EF7-TC engine. In order to better compare and evaluate the results, based on experiences of previous researches, four different injection points on the intake manifold was considered. Results comparison showed the particle tracking method can qualitatively predict the distribution of recirculated gases between the intake manifold runners with a high confidence level. Only one qualitative difference between experimental and numerical results is observed. Besides, it is revealed that with decreasing the recirculated gas rate the accuracy of particle tracking method is enhanced and differences between experimental and numerical results are decreased. In addition, by comparing the results of four injection points it was showed that the particle tracking method is more accurate for injection points which distribute recirculated gases more uniformly.

The low amount of pollutant and smooth way of transition of some fuels such as liquid petroleum gas (LPG) for usage in cars have always been the concern of some consumers. Duo to the storage of this fuel with a pressure of 8 to 10 bar in non-standard tanks, there is a possibility of risk and danger likewise explosion and fire. In this article, the scenario of fire-caught car that caused the Boiling Liquid Expanding Vapor Explosion (BLEVE) and the formation of a fireball with a diameter of 19.14 meters has been investigated. The effect of pressure in the 60-liter tank and then the effect of radiation in the incident have been modeled. accordingly The results have illustrated the fact that until 2 meters from the liquid gas tank explosion site, the pressure continues up to 8 bar, and the radiation effect reaches 4 bar in a distance of 48 meters from the center of the accident, and in a distance of 14.60 meters, the amount of thermal radiation reaches 37.5 kilowatts per square meter, which it is very worrying. By considering the pressure and thermal radiation effects, the safe distance and the amount of damage are predicted. The results can be used to improve safety and revise the construction of LPG tanks to reduce losses.

The Gas to Gasoline (GTG) process includes conversion of natural, flare, and associated gas into synthetic fuels that can be compositionally upgraded and adjusted into different useful hydrocarbon fuels including gasoline, liquid petroleum gas (LPG), and fuel gas. Commonly, the GTG process involves three stages: 1) Synthesis gas (syngas) production unit 2) Methanol production unit 3) Methanol to Gasoline production unit (MTG). In this study, an integrated Flare Gas to Gasoline (FGTG) process for converting flare gas to gasoline, LPG and fuel gas is simulated using the Aspen HYSYS v. 8.8 simulator. The steam methane reforming (SMR) unit, the syngas to methanol unit, and the MTG unit are configured for simulation as an integrated FGTG process. In order to reduce carbon dioxide gas emissions to the atmosphere, a novel closed arrangement for the FGTG process (recycling configuration) is described and simulated. The simulation results demonstrate that by recycling all gas emissions, such as flare and off gas from the methanol and MTG units back into the process cycle, gasoline and LPG productivity can be increased on average by about 53% and 10%, respectively, compared to a base FGTG configuration that does not involve such recycling. The integrated simulation is supported by sensitivity analysis based on FGTG plants of various natural gas capacities (from 70,000 to 130,000 lb./hr.) as the adjustable (independent) variable and gasoline, LPG, and fuel gas selectivity as the dependent variables. Results of the simulation cases reveal that the total productivity of the integrated FGTG process could be increased in terms of flare gas mass flow, with the selectivity of products remaining approximately fixed for different plant capacities (i.e., at 75% for the gasoline product). Moreover, the utilities and energy consumption of the FGTG process is compared for several sensitivity cases. The results reveal that by increasing the capacity of the gas feed (natural gas mass flow) the Energy Index (i.e., total utilities consumption to product flow rate) decreased by about 8% and 47% in the base and recycling configurations, respectively. This finding suggests that an FGTG plant becomes more energy efficient at in higher-capacity plants.

Liquefied petroleum gas (LPG) is considered one of the gases widely used in many industrial and residential sectors. Still, due to its different compositions, mainly propane (C3H8) and butane (C4H10), it can have other combustion characteristics. This paper aims to conduct an experimental analysis to study the impact of LPG composition on the stability map (limits of blowoff and flashback) of the premixed flame in a tangential swirl burner. Four LPG mixtures were used with different proportions of ethane (C2H6), propane (C3H8), butane (C4H10), and pentane (C5H12). Three burner nozzles at diameters of 20, 25, and 30 mm have been used, which gave three swirl numbers of 0.918, 1.148, and 1.377, respectively. The results indicate that increasing the swirl number (S) from 0.918 to 1.377 for all LPG mixtures accelerated the flashback propensity (getting worse) while the blowoff resistance improved; thus, a rising S gave a better stability map. As for the effect of the LPG composition, it was found that the maximum flame temperature was for the LPG mixture containing high percentages of butane (C4H10), while the lowest was for the mixture containing fewer percentages of butane. Changing the LPG composition had an apparent effect on the flashback limits and a slight effect on the blowoff limits; it was found that mixtures containing high percentages of butane increased flame speeds and increased the flashback propensity. Compared to LPG mixtures, the flame stability map was widest for LPG mixtures containing lower percentages of butane. Therefore, LPG with propane (C3H8) proportions higher than butane (C4H10) reduces flame temperature, flame speeds, and flashback propensity, thus improving the stability map.

Oil and gas processing plants are one of the most air pollutant industries. In this paper, gaseous air pollutants emission factors were estimated for pollutant sources in an Iranian Natural Gas Liquids (NGL) plant using fuel analysis method and published emission factors. The results showed that the main pollutant sources in this unit are gas flare, gas turbines, pit and boiler. Total Hydro Carbons (THC) and CH4 emissions from gas flares and NO2 emission from gas turbine are higher than any other pollutant sources. Activity based emission factors were determined as 513.3, 2731.0, 0, 1805.3 and 225.6 g/1000kg LPG for NO2, CO, SO2, THC and CH4 respectively on the basis of LPG production in the unit. Because of possible gas leakages from the units, CH4 emission factor have larger margin of error. Calculated emission factors can be used for emission estimation of air pollutant in other similar NGL processing units.

Petroleum products such as gasoline، gasoil and liquefied petroleum gas (LPG) are considered as essential goods some of which Iran is dependent on import to provide. Thus، under-supplying such strategic goods arguably leads to a decrease in production in other sectors، income reduction. In order to analyse this situation، it is improper to apply Social Accounting Matrix. Instead، this paper draws on a Modified Supply-Driven Social Accounting Matrix in particular contexts. At the same time، 2006 Energy-Carrier Social Accounting Matrix is applied. The findings show that a price rise in petroleum products such as gasoline، gasoil and liquefied petroleum gas (LPG) mostly has a negative effect on Producer Price Index (PPI) in service، industry، and agriculture، respectively. Within these circumstances، rather than Cost of Urban Living Index، Cost of Rural Living Index will be negatively affected. But، with an increase in the price of gasoline، cost of living index of urban households is more than the cost of living index of rural households، and the increase in the price of gasoline and LPG has reverse impacts.

Carbon dioxide is a critical driver of climate change and a significant byproduct of numerous anthropogenic activities, particularly industrial processes. Contemporary developments in the energy sector underscore the necessity of CO₂ valorization, specifically its transformation into valuable chemicals or fuels. This study focuses on the direct hydrogenation of carbon dioxide for the synthesis of liquefied petroleum gas (LPG). The research utilizes a beta zeolite catalyst augmented with zirconium nanoparticles to investigate the direct hydrogenation of carbon dioxide for liquefied petroleum gas (LPG) synthesis. The experimental protocol employs a fixed bed reactor to evaluate crucial operational variables, including reaction temperature and residence time. The results indicate that optimal conditions for liquid gas production are achieved at a temperature of 380°C with a residence time of 12 g.h.mol⁻¹. Under these specified experimental parameters, the study reports a carbon dioxide conversion rate of 29.2% and a selectivity of 39.3% towards hydrocarbon products. The distribution of hydrocarbon products was further analyzed, revealing that ethane, LPG, and C2+ hydrocarbons comprised 10.2%, 66.2%, and 15.2% of the product stream, respectively. Fourier-transform infrared (FTIR) spectroscopy of pyridine adsorption on the Zr/zeolite-β catalyst identified the formation of new Brønsted and Lewis acid sites, which are essential for facilitating the chemical conversion of carbon dioxide. The catalyst demonstrated remarkable stability, maintaining its activity over an extended period of 100 hours without any detectable deactivation. During the experimental period, the carbon dioxide conversion rate remained consistently stable at approximately 20.5%. Additionally, the catalyst exhibited high selectivity towards the desired products, achieving selectivities of 10.8% for methane, 60.5% for LPG, and 18.3% for C₂+ hydrocarbons. However, after 100 hours of operation, catalyst deactivation was observed, resulting in a decline in CO₂ conversion to 12.3% and a reduction in LPG selectivity to 52.4%.

In this paper, tin dioxide (SnO2) nanowires with different diameter have been fabricated for gas sensor applications by a chemical vapour deposition (CVD) technique. Alumina (Al2O3), quartz, and gold Au-coated silicon (Si) (100) were used as substrates. X-ray diffraction (XRD), photoluminescence spectroscopy (PL), and a scanning electron microscope were employed to characterize the synthesized products. Nanostructured gas sensor devices were fabricated using SnO2 nanowires as the active layer and gold (Au) for the electrode contacts. Gas sensing performance of synthesized SnO2 nanostructures are studied for two most widely used gases suchas liquefied petroleum gas (LPG) and ethanol (C2H5OH) vapor. The responses of SnO2 nanowires were checked at different temperatures ranging from 50 to 300 °C, so as to optimize sensing efficiency. Sensing performances were discussed for parameters such as response time, recovery time, and operating temperature. Fabricated sensor is shown a high sensitivity to low concentrations of LPG at elevated temperatures. Prepared sensor was revealed fast response and recovery time at working temperature of 200 °C for ethanol vapor detection.