The present research was focused on the determination and removal of sulfur-containing compounds in industrial emissions of liquefied petroleum gas purification processes in petrochemical plants ...located in the USA, Brazil, Colombia, Spain, and Italy. For the analysis of volatile sulfur compounds (VSCs), an improved analytical methodology was implemented. The performance of the method was evaluated for eight VSCs in a linear dynamic range between 0.1 and 50 ppm. The concentrations of the eight VSCs in the deethanizer affluents ranged from 11 to 49 ppm for all the studied plants, which exceed the limits specified by institutions and administrations in occupational health and safety. The concentrations of the eight VSCs in the splitter affluents were lower than 4 ppm for all the considered plants. The emissions from each column depended upon its operating rate, with the highest concentrations estimated at 45 TM kgsup.−1 and the lowest ones at 25 TM kgsup.−1 . A zeolite-packed prototype column was fitted at the outlet of the splitter and deethanizer columns to reduce the environmental effect of the examined VSCs. This technique was verified and put into practice on an industrial scale, obtaining VSC removal percentages of between 85 and 91%.
Towards enhancing the thermal performance and fuel flexibility of existing domestic cooking stoves, the present work employs the heat recirculation mechanism of the porous medium (PM) combustion to ...these burners offering greater fuel compatibility for both liquefied petroleum gas (LPG) and renewable fuel dimethyl ether (DME). To establish the advantages of DME combustion than that of LPG within the stove, experimental measurements and numerical modeling are performed in a two-layer PM burner. The numerical model is used to investigate the dynamics of DME flame in the PM through reaction path analyses. Both experiment measurements and numerical predictions show lower CO emissions for DME flame than that of LPG flame inside the PM stove. With the use of DME instead of LPG, following the guideline of World Health Organization, the maximum allowable equivalence ratio can be extended from 0.4 to 0.5 and the thermal load from 4.0 kW to 5.0 kW. Moreover, the total heat generation rate, the gas- and solid-phase temperatures and radiant efficiencies of the burner with DME flame are higher than that with LPG flame at the same input conditions. However, the stability ranges of DME flame are found to be less than that of LPG flame.
•Investigation of PM cooking stove compatible for both LPG and DME.•Temperature distributions within the PM stove are compared for both the fuels.•Radiation efficiency is higher for DME fired stove than that of LPG.•CO emission is low for the burner with DME flame.•Dynamics of DME flame in the PM burner are studied.
Over two-thirds of Indians use solid fuels to meet daily cooking energy needs, with associated negative environmental, social, and health impacts. Major national initiatives implemented by the Indian ...government over the last few decades have included subsidies for cleaner burning fuels like liquid petroleum gas (LPG) and kerosene to encourage a transition to these. However, the extent to which these programs have affected net emissions from the use of these improved fuels has not been adequately studied. Here, we estimate the amount of fuelwood displaced and its net emissions impact due to improved access to LPG for cooking in India between 2001 and 2011 using nationally representative household expenditure surveys and census datasets. We account for a suite of climate-relevant emissions (Kyoto gases and other short-lived climate pollutants) and biomass renewability scenarios (a fully renewable and a conservative non-renewable case). We estimate that the national fuelwood displaced due to increased LPG access between 2001 and 2011 was approximately 7.2 million tons. On aggregate, we estimate a net emissions reduction of 6.73 MtCO2e due to the fuelwood displaced from increased access to LPG, when both Kyoto and non-Kyoto climate-active emissions are accounted for and assuming 0.3 as the fraction of non-renewable biomass (fNRB) harvested. However, if only Kyoto gases are considered, we estimate a smaller net emissions decrease of 0.03 MtCO2e (assuming fully renewable biomass harvesting), or 3.05 MtCO2e (assuming 0.3 as the fNRB). We conclude that the transition to LPG cooking in India reduced pressures on forests and achieved modest climate benefits, though uncertainties regarding the extent of non-renewable biomass harvesting and suite of climate-active emissions included in such an estimation can significantly influence results in any given year and should be considered carefully in any analysis and policy-making.
Prevailing safety guidance for the transportation of liquefied natural gas (LNG) is based on the guidance for liquefied petroleum gas (LPG) transportation; therefore, the safety considerations for ...LNG and LPG transport must be compared. A literature review was performed to understand and compare the development of research into LNG and LPG, their transportation, and the safety considerations involved. The literature review revealed key hazard differences, as well as the lack of transport safety studies compared to the vast field of research for both substances. With the scientific background established, the chemical and physical properties of LNG and LPG are compared, then the hazards related to their properties. Finally, with knowledge of the properties and hazards of both LNG and LPG, the available risk analyses are discussed. LNG transport has undergone minimal accident frequency analysis compared to LPG transport. Most of these frequency analyses have been for marine transport and contain high uncertainties in the determined probabilities due to sparse available data. It is also apparent that consequence analysis studies have not been adequately explored; however, modelling software provides consequence understanding via simulation. LNG transportation lacks the knowledge base from research and practice that LPG transportation has, and due to limited incident history, the lack of research into boiling liquid expanding vapour explosion (BLEVE) potential of LNG and the lack of understanding of the severity, likelihood, and repeated explosions of rapid phase transition limit understanding of the risk of LNG transportation. Potential future research is recommended to address these vital knowledge gaps.
•The MAPLE technique is applied to immobilize hemoglobin (Hb) upon LPGs.•The functionalized LPGs were used to selectively measure glucose concentration.•A total spectral shift of 13 nm was obtained ...for a concentration of 1.3 mmol/L.•We report reliable detection of glucose concentration down to 0.1 mmol/L.•The response is shown to be selectively caused by the glucose solutions alone.
In this paper we report for a highly efficient sensor able to detect low-level glucose in saliva using ultra-sensitive long-period grating (LPG) fibre structure. Hemoglobin was directly immobilized on the structure by matrix-assisted pulsed-laser evaporation (MAPLE) method. Glucose binds to hemoglobin and the result is a glycated hemoglobin, the formation of which we detect. We demonstrate that the implemented technology allows for a clear relationship between glucose concentration and the spectral shift. As a result, a reliable detection of glucose concentration as low as 0.1 mmol/L is demonstrated.
Three billion people in low- and middle-income countries are exposed to household air pollution as they use biomass fuel for cooking. We investigated the associations between solid fuel use and ...nasopharyngeal (NP) inflammation, as well as the associations between high pneumococcal density and NP inflammation, in mothers and children in rural and urban Ethiopia.
Sixty pairs of mothers (median age, 30 years; range, 19-45 years) with a child (median age, 9 months; range, 1-24 months) were included from rural Butajira (n = 30) and urban Addis Ababa (n = 30) in Ethiopia. The cohort was randomly selected from a previous study of 545 mother/child pairs included 2016. Questionnaire-based data were collected which included fuel type used (solid: wood, charcoal, dung or crop waste; cleaner: electricity, liquefied petroleum gas). Nasopharyngeal (NP) samples were collected from all mothers and children and analyzed for the levels of 18 cytokines using a Luminex immunoassay. Pneumococcal DNA densities were measured by a real-time multiplex PCR and a high pneumococcal density was defined as a cyclic threshold (Ct) value ≤ 30.
Mothers from rural areas had higher median CXCL8 levels in NP secretions than those from urban areas (8000 versus 1900 pg/mL; p < 0.01), while rural children had slightly higher IL-10 levels than those from the urban area (26 vs 13 pg/mL; p = 0.04). No associations between fuel type and cytokine levels were found. However, a high pneumococcal density was associated with higher levels of cytokines in both mothers (CCL4, CXCL8, IL-1β, IL-6 and VEGF-A) and children (CCL4, CXCL8, IL-1β, IL-6 and IL-18).
No significant associations were found between solid fuel use and NP inflammation in Ethiopian mothers and children, but the inflammatory activity was higher in individuals living in the rural compared to the urban area. In addition, high cytokine levels were associated with high pneumococcal density in both mothers and children, indicating a significant impact of NP pathogens on inflammatory mediator levels in upper airways.
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•Nano HZSM-5 with interconnected mesopores and shortened microporous channels.•Low Brönsted acid amount as well as low acid density.•Suppression of side reactions due to less ...diffusion resistance and weak acidity.•Dramatic promotion in selective production of propylene and ethylene from LPG.
On microporous micron HZSM-5 catalyst liquefied petroleum gas (LPG) tends to produce high heavier hydrocarbons (HCs) and methane. Here nano HZSM-5 with regular pores by recrystallization procedure was investigated for the selective transformation of LPG. HZSM-5 with different crystallite aggregation, mesopore property and acidity was synthesized. Mesopore-connected, micropore-shortened and weakly acidic HZSM-5 catalyst enhances remarkably the formation of light olefins from LPG. At reaction temperature of 600 °C and contact time (W/F) of 15 g·h/mol, the selectivity of propylene and ethylene reached 68.3% at the total conversion of LPG of 58.8%. Products of C5+ HCs and methane were reduced. Due to less diffusion resistance of synthetic HZSM-5 and its low Brönsted acid amount as well as low total acid amount, adverse side reactions are suppressed.
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•The effect of various Mg(x)Fe(1−x)O4 nanostructures on LPG sensing was studied.•The proposed sensor exhibited high response and selectivity at low temperature.•The developed flexible ...sensor can be used in wearable applications.
This report talks in detail about the successful synthesis of nanoparticle material Mg(x)Fe(1−x)2O4 (x = 0.1, 0.5 and 0.9) through a simple and inexpensive sol-gel auto-combustion process and its application as a gas sensor. A detailed description of the dependence of liquefied petroleum gas (LPG) sensing performance on the various compositional ratios of Mg(x)Fe(1−x)2O4 (x = 0.1, 0.5 and 0.9) have been investigated. The device was prepared by drop-drying method on lithographic patterned flexible interdigitated electrodes (IDEs). The characterizations revealed that at the specific composition of Mg(x)Fe(1−x)2O4 (x = 0.5), the prepared material performed with supreme sensitivity at 90 °C with respect to the commercially existing gas sensors for 500 ppm of LPG at applied voltage 1 V. Additionally, this device reproduced the similar response in bending test also. The sensor has exhibited related stability even after few days and maintained the stability quite well for several cycles.
Existing efforts to promote cleaner fuels have not achieved exclusive use. We investigated whether receiving 12 months of free liquefied petroleum gas (LPG) and behavioral support could motivate ...continued purchase and use.
The Cardiopulmonary outcomes and Household Air Pollution (CHAP) trial enrolled 180 women. Half were randomly assigned to an intervention group, which included free LPG delivered in months 1–12 followed by a post-intervention period in which they no longer received free fuel (months 13–24). For the purposes of comparison, we also include months 1–12 of data from control participants. We tracked stove use with temperature monitors, surveys, and observations, and conducted in-depth interviews with 19 participants from the intervention group at the end of their post-intervention period.
Participants from the intervention group used their LPG stove for 85.4 % of monitored days and 63.2 % of cooking minutes during the post-intervention months (13–24) when they were not receiving free fuel from the trial. They used a traditional stove (fogón) on 45.1 % of days post-intervention, which is significantly lower than fogón use by control participants during the intervention period (72.2 % of days). In months 13–24 post-intervention, participants from the intervention group purchased on average 12.3 kg and spent 34.1 soles (10.3 USD) per month on LPG. Continued LPG use was higher among participants who said they could afford two tanks of LPG per month, did not cook for animals, and removed their traditional stove. Women described that becoming accustomed to LPG, support and training from the project, consistent LPG supply, choice between LPG providers, and access to delivery services facilitated sustained LPG use. However, high cost was a major barrier to exclusive use.
A 12-month period of intensive LPG support achieved a high level of sustained LPG use post-intervention, but other strategies are needed to sustain exclusive use.
•Exclusive clean fuel use is necessary for realizing full health and other benefits.•Mixed methods investigation to inform achievement of sustained LPG use in Peru•One year of free fuel motivated sustained (but not exclusive) LPG use post-trial.•Sustained use motivated by becoming accustomed to LPG and training during trial•Consistent LPG supply, multiple distributors, and delivery services were also key.
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