Biofuel Combustion Research Articles

Diverting residual biomass to energy use: Quantifying the global warming potential of biogenic CO2 (GWPbCO2)

AbstractTo calculate the global warming potential of biogenic carbon dioxide emissions (GWPbCO2) associated with diverting residual biomass to bioenergy use, the decay of annual biogenic carbon pulses into the atmosphere over 100 years was compared between biomass use for energy and its business‐as‐usual decomposition in agricultural, forestry, or landfill sites. Bioenergy use increased atmospheric CO2 load in all cases, resulting in a 100GWPbCO2 (units of g CO2e/g biomass CO2 released) of 0.003 for the fast‐decomposing agricultural residues to 0.029 for the slow, 0.084–0.625 for forest residues, and 0.368–0.975 for landfill lignocellulosic biomass. In comparison, carbon emissions from fossil fuels have a 100GWP of 1.0 g (CO2e/g fossil CO2). The fast decomposition rate and the corresponding low 100GWPbCO2 values of agricultural residues make them a more climate‐friendly feedstock for bioenergy production relative to forest residues and landfill lignocellulosic biomass. This study shows that CO2 released from the combustion of bioenergy or biofuels made from residual biomass has a greenhouse gas footprint that should be considered in assessing climate impacts.

A HyChem combustion model of methyl decanoate

Liquid biofuels are promising carbon-neutral fuels, which contribute to the realization of low-carbon utilization of organic fuels. Due to the difficulty in developing kinetic models for liquid biofuels with complex high molecular components, short-chain fuels are often used as surrogate fuels to study the chemical kinetics of biofuels such as biodiesels. But this approach is complex to model and need to consider the kinetic coupling of the fragments of fuel components. The HyChem approach, which considers the combustion characteristics of the fuel directly, has been proposed to model the combustion of real multi-component and single-component hydrocarbon fuels. It describes the fuel decomposition with a lumped model and the oxidation of pyrolysis fragments with a detailed kinetic model. To preliminarily test the feasibility of the HyChem approach to oxygenated fuels, it was applied to the combustion modeling of methyl decanoate, a typical methyl ester and an important biodiesel surrogate, and the model parameters were constrained by speciation data from literature. Special attention was paid to the evolution of the oxygen element. The results show that the pyrolysis and oxidation of methyl decanoate are two separable processes in time and space, and the methyl decanoate HyChem model predictions had a reasonably good agreement with experimental measurements of speciation, ignition delay time, and flame speeds. To further test the application of HyChem method for biodiesel, we also make a preliminary attempt for methyl palmitate, which is a real biodiesel component. These tests suggest that the HyChem method can be applied to more oxygenated fuels, which provides an efficient modeling approach for complex biofuel combustion.

친환경 바이오연료를 사용하는 난방시스템 디자인설계 및 환경시험평가

Research and development for alternatives to fossil fuels such as coal and petroleum have progressed considerably worldwide. Among clean fuels, bio-diesel has been a representative fuel and it was used for the following advantages; renewable, ready to use with low fine dust emission and non-toxicity. But it is expensive and cause strain on local resources. In our study, to resolve these issues, we developed two types of heating systems by direct input of waste cooking oil, and the heating system was optimized through mechanical design and design process. In addition, we conducted an environmental test to evaluate the reliability and environmental characteristics of the developed device. Firstly, through the design modification of heat recirculation system, more efficient combustion for the complete combustion of bio-fuel(waste cooking oil), was possible. As for the heating system, two products (tube heating system, agricultural hot air blower) were optimized for management convenience, space utilization, and efficiency improvement by 6-step design. From the environmental test result, the combustion efficiency of the heating system was up to 99%, the average oxygen concentration was 8.3%, and the CO concentration was 7.9 ppm for a stable combustion, NOx was up to 67 ppm, and SOx was not detected.

Novel Design for Rotary Burner for Low-Quality Pellets

The burning of low-quality fuels causes several problems in the operation of combustion equipment, which can negatively affect the equipment’s efficiency. The possibilities for the burning of pellets made from low-quality raw materials are limited mainly by the fusibility of the ash, which settles and melts on the surfaces of the burner, gradually causing it to clog. Smelted ash also causes a decrease in heat transfer efficiency, which negatively affects the overall efficiency of the heat source. A possible solution is provided by burners with a rotating combustion chamber, where the contact time of the molten ash with the walls of the burner is shortened, and thus there is no significant melting of the ash in the burner. This manuscript is dedicated to summarizing the current state of development of burners with a rotary chamber, presenting a novel design for such a burner, and providing an analysis of that design. To conclude, the results of experimental measurements on a classic burner and a burner with a rotary chamber are presented, including a comparison and evaluation mainly in terms of emissions. The novel-designed rotary burner achieved a higher heat output than the retort burner, but a similar thermal efficiency. The rotary burner produced 32.5% lower CO emissions, 12.5% higher NOx emissions, 23% lower OGC emissions, and 44.7% higher PM emissions in comparison with a retort burner under the same conditions. This novel rotary burner concept could, after optimization, be a suitable option for efficient combustion of alternative biofuels.

A review study on the use of dimethyl ether in diesel engines: effects on CO2 emissions

Emissions from vehicles and other fuel combustion systems can alter the composition of the atmosphere and augment its capacity to absorb heat. These gases, which are effective at trapping heat, are known as greenhouse gases and include all gases found in vehicle emissions. Reducing the emissions of carbon dioxide (CO2) has become an urgent necessity around the world, and many countries have imposed limits on their CO2 output. Using biofuels in automotive engines is an effective way of reducing greenhouse gas emissions. The CO2 emissions emitted from the combustion of biofuels are absorbed as trees and plants grow. Biofuels can be used either as pure fuels or blended with conventional fuels. Most research has declared that the most effective way to reduce greenhouse emissions is the use of various biofuels. Therefore, it is essential to assess the outcomes of research regarding alternate fuels or fuel additives to determine their proper utilization. Using of diesel engines can also help reduce CO2 emissions as they emit less CO2 emissions than gasoline engines. This review study investigates the effects the using of dimethyl ether on CO2 emissions in diesel engines. The results showed that CO2 emissions decrease when using the pure DME and DME blends with diesel and LPG fuels due to the oxygen content and the lower carbon to hydrogen ratio of DME. The decrements in CO2 emissions for pure DME, diesel–DME blends and LPG–DME blend are about 5.2–18.3%, 3–41.6% and 10.6–16.4%, respectively.

Source apportionment of black carbon aerosols in winter across China

Black carbon (BC) aerosols emitted from incomplete combustion of fossil fuels, biofuels, and biomass have significant effects on the environment and human health. Combustion-derived BC aerosols are an important component in haze pollution. High concentrations of BC aerosols were found in fine particulate matter (PM2.5) in China, and source apportionment was the strategy underpinning targeted mitigation actions. Here, we present a Bayesian statistical model, a three-dimensional array of a stable carbon isotope (δ13C) and the ratios of non-sea-salt K+ to BC (nss-K+/BC) and ΔBC/ΔCO that is a reasonably inexpensive and rapid way to constrain BC source apportionments. This study analyzed 551 daily PM2.5 samples collected in January 2018 in 18 large cities and at 1 remote site scattered across China. The results show that BC concentrations were generally higher in cities in northern China than they were in cities in southern China. Source apportionments indicate that BC in 44% of cities was mainly from liquid fuel combustion. In other sites, including 39% of cities, one suburban site, and one remote site, BC was mainly from biomass burning. These findings suggest that to improve air quality, the Chinese government should further strengthen controls on liquid fuel combustion and consider controlling biomass burning.

Performance, Emission, and Catalytic Activity Analysis of AL2O3 and CEO2 Nano-Additives on Diesel Engines Using Mahua Biofuel for a Sustainable Environment.

Diesel engines are particularly harmful to the environment due to the high levels of pollution they release. This led to the discovery of a sustainable and environmentally friendly fuel source. Mahua oil transesterified into biofuel seems to be the most popular option. The possibilities for nano-additions to enhance engine performance while simultaneously lowering pollution levels are substantial. In this research, 20% by proportion mahua biodiesel (MAH B20) was mixed with varying concentrations of aluminum oxide (Al2O3) and cerium oxide (CeO2) nanoparticles, and their joint effects on a mono-cylinder diesel engine working at a speed of 1500 revolutions per minute (rpm) were evaluated. With the use of an ultrasonic bath, the nanoparticles and MAH B20 were blended at varying concentrations and a surfactant was added for stability. The investigations concluded that the combustion and emission properties of mahua biofuel were improved because of the higher volume to surface area ratio of the combined Al2O3 and CeO2 nanostructures. The best results are found when mahua biofuel is mixed with Al2O3 and CeO2 each at 100 parts per million (ppm). The blend MAH B20 AL100 CE100 exhibits reduced brake specific fuel consumption (BSFC) by 3.25%, increased brake thermal efficiency (BTE) by 1.39%, and reduced emissions of hydrocarbon (HC), oxides of nitrogen (NOX), and carbon monoxide (CO) by 30.73, 1.27, and 44.13%, respectively.

Source sectors underlying PM2.5-related deaths among children under 5 years of age in 17 low- and middle-income countries

BackgroundFine particulate matter (PM2.5) from different source sectors might differ in toxicity. However, data from large-scale studies on vulnerable children in low- and middle-income countries (LMICs) are insufficient. ObjectiveTo analyze the association of under-five death (U5D) with long-term exposure to PM2.5 from different sources. MethodWe evaluated demographic and health survey data for 79,995 babies born in 2017 in 16 Asian and African LMICs (AA-LMICs) and a Latin America low-income country (i.e., Haiti). Long-term exposure to PM2.5 was assessed by a well-established product that attributed the annual concentration to 20 source sectors in 2017. The associations of survival during < 5-year periods with each source-specific concentration of PM2.5 were analyzed by Cox regression with multiple adjustments. We derived a multiple-pollutant ridge regression model to estimate the joint exposure–response function (JERF) between U5D and PM2.5 mixtures. To evaluate how sources affected PM2.5 toxicity, we evaluated the number of U5Ds attributable to PM2.5 based on the source profiles for 88 AA-LMICs. ResultsAccording to the single-pollutant model, the risk of U5D increased by 7% (95% confidence interval [CI]: 5%, 9%) for each 10 μg/m3 increment in total PM2.5 concentration. The model performance was lower than that of the multiple-pollutant ridge regression model. For each 10 μg/m3 increment in PM2.5, the excess risk of U5D ranged from 6% (95% CI: 4%, 9%) in Nepal to 10% (95% CI: 6%, 14%) in Mauritania. Based on the JERF, PM2.5 contributed to 817,647 (95% CI: 585,729, 1,050,439), i.e., 28.0% (95% CI: 20.1%, 35.8%), of all U5Ds across the 88 AA-LMICs. The PM2.5-related U5Ds were mostly attributable to PM2.5 produced by desert dust, followed by solid biofuel combustion and open fires. ConclusionThe average toxicity of PM2.5 varied by source profile, which should be taken into consideration when planning public health interventions. For some AA LMICs, natural sources of PM2.5 had the most significant health effects, and should not be ignored to ensure the protection of child health.

Study of Low- and Intermediate-Temperature Oxidation Kinetics of Diethyl Ether in a Supercritical Pressure Jet-Stirred Reactor.

Growing demand for low-emission and high-efficiency propulsion systems spurs interest in understanding low-temperature and ultra-high-pressure combustion of alternative biofuels like diethyl ether (DEE). In this study, DEE oxidation experiments are performed at 10 and 100 atm, over a temperature range of 400-900 K, at fuel-lean, stoichiometric, and fuel-rich conditions by using a supercritical pressure jet-stirred reactor (SP-JSR). The experimental data show that DEE is very reactive and exhibits an uncommon low-temperature oxidation behavior with two negative temperature coefficient (NTC) zones. The first NTC zone is mainly governed by the competition reactions of QOOH + O2 = O2QOOH and QOOH = 2CH3CHO + OH, while the second one is mainly governed by the competition reactions of R + O2 = RO2 and the β-scission reaction of fuel radical R. It is shown that the increase of pressure stabilizes RO2 and promotes HO2 chemistry. Moreover, the branching ratios of β-scission reactions of R and QOOH decrease. As a result, it is shown that, with the increase of pressure, both NTC zones become weaker at 100 atm. In addition, the intermediate-temperature oxidation is shifted considerably to lower temperature at 100 atm. The existing DEE model in the literature well predicts the experimental data at low temperature; however, it underpredicts the fuel consumptions at intermediate temperature. The H2/O2 subset in the existing DEE model is updated in this study based on the Princeton updated HP-Mech, including the singlet/triplet competing channels of HO2 related reactions. The updated model improves the overall predictability of key species, especially at intermediate temperature.

Environment from A to Z, from Air to Zero waste

First and foremost, I would like to thank all supporters of the journal, that is, all authors who submit and publish their contributions in CLEAN – Soil, Air, Water, all reviewers who invest time and put submitted articles through their paces, and, of course, all readers who make contributions really come alive. Thank you all for helping to shape the journal. Today I start with this editorial a small series “Environment from A to Z, from Air to Zero waste”. The world we live in is unique as far as we know and so we should strive to preserve this one world. In this journal we will find articles that 1) look at data on air, soil, and water quality and 2) offer solutions for a cleaner environment. Everything from A to Z. A for Air, which we need to live. Air that we breathe and that should be free of pollutants so that we stay healthy. On the one hand, we have to monitor the air quality to know how clean the air is that surrounds us. On the other hand, we then need to use that knowledge to take the necessary actions to ensure that the air is kept clean. B for Biofuels, which is obtained from processed or refined biomass. Combustion of biofuels produces CO2, which is in turn absorbed and stored by plants, thus restarting the cycle of biomass production and use. C for Climate change, which is already being discussed publicly. We are already seeing some of the effects with extreme weather, forest fires, thawing permafrost, and so on. How can we mitigate overheating in cities or channel or use rainwater/stormwater better, what form of land use is promising, what are the possibilities for CO2 fixation, and many other questions we have to ask ourselves and find answers for. D as in Drinking water, the gold of tomorrow, an elixir of life without which we cannot exist. Keeping drinking water clean and, above all, supplying it to people, animals and plants is a Herculean task. Extreme weather conditions in all regions of the world sometimes present us with almost unsolvable problems: Inputs of pollutants through flooding or salinization of soils and thus also of water during prolonged periods of drought. E for E-waste. Electrical devices that are no longer used, whether broken or functional but technically outdated, accumulate by the ton every year. A plague, if you will. But we can also view this scrap as a resource and find new ways to obtain valuable materials such as precious metals. CLEAN covers all aspects of sustainability and environmental safety including those mentioned here under the first five letters of the alphabet. Do you have submissions that address environmental sustainability issues such as air pollution, waste management, water cycle and environmental protection? I look forward to receiving your submission in CLEAN. More on the letters F through I/J in the next editorial. I wish you a good and successful 2023. Stay healthy. Yours sincerely, phenheik@wiley.com

Evaluation of Particulate Matter (PM) Emissions from Combustion of Selected Types of Rapeseed Biofuels

The manuscript describes the results of an experimental study of the level of PM (particulate matter) emissions arising from the combustion of two selected types of biomass (i.e., rapeseed straw pellets and engine biofuel (biodiesel, FAME)), which were derived from rapeseed. The PM emissions from the combustion of biofuels were compared with those obtained from the combustion of their traditional counterparts (i.e., wood pellets and diesel fuel). Both types of pellets were burned in a 10 kW boiler designed to burn these types of fuels. The engine fuels tested were burned in a John Deere 4045TF285JD engine mounted on a dynamometer bench in an engine dyno, under various speed and load conditions. A Testo 380 analyzer was used to measure the PM emission levels in boiler tests, while an MPM4 particle emission meter was used in the engine tests. The combustion (under rated conditions) of rapeseed straw pellets resulted in a significant increase in PM emissions compared to the combustion of wood pellets. The PM emissions during the combustion of wood pellets were 15.45 mg·kg−1, during the combustion of rapeseed straw pellets, they were 336 mg·kg−1, and the calculated emission factors were 44.5 mg·MJ−1 and 1589 mg·MJ−1, respectively. In the engine tests, however, significantly lower particulate emissions were obtained for the evaluated biofuel compared to its conventional counterpart. The combustion of rapeseed oil methyl esters resulted in a 40–60% reduction in PM content in the exhaust gas on average for the realized engine speeds over the full load range compared to the combustion of diesel fuel.

Assessment of air quality in North Korea from satellite observations

North Korea’s air quality is poorly understood due to a lack of reliable data. Here, we analyzed urban- to national-scale air quality changes in North Korea using multi-year satellite observations. Pyongyang, Nampo, Pukchang, and Munchon were identified as pollution hotspots. On a national scale, we found that North Korea experienced 6.7, 17.8, and 20.6 times greater amounts of nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO) per unit primary energy supply (PES) than South Korea from 2005 to 2018. Besides, North Korea had a 24.3 times larger aerosol optical depth (AOD) per PES than South Korea from 2011 to 2018. Severe CO and aerosol pollution is aligned with extensive biofuel combustion. High SO2 pollution corresponds with the strong coal dependence of the industry. The change rates of the national average columns for NO2, SO2, and CO were + 3.6, –4.4, and –0.4 % yr−1, respectively. The AOD change rate was –4.8 % yr−1. Overall decreasing trends, except for NO2, are likely due to a decline in coal-fired PES. Positive NO2 trends are consistent with increasing industrial activities. Each pollutant showed consistent patterns of linear trends, even after correcting the influence of transboundary pollution. Flue gas control and biofuel consumption reduction seem necessary to improve North Korea’s air quality.

Levels, distribution, sources and children health risk of PAHs in residential dust: A multi-city study in China

BackgroundPolycyclic aromatic hydrocarbons (PAHs) are typical residential pollutants mainly from biofuel combustion that impose inevitable risk to children. The PAHs in residential dust is universal in most Chinese households with an obvious public health concern. MethodsIn this observational study, a total of 235 residential dust samples from 8 Chinese cities (Panjin, Shijiazhuang, Lanzhou, Luoyang, Xi'an, Wuxi, Mianyang, and Shenzhen) were collected from April 2018 to March 2019, which were extracted and analyzed for 16 priority PAHs by HPLC/FD-UV. Diagnostic ratios, hierarchical clustering analysis and principal component analysis were applied simultaneously for source apportionments. Incremental lifetime cancer risk was employed to estimate children's health risks based on the assumed exposure scenarios. Spearman correlation, Mann-Whitney U test, Kruskal-Wallis H test and Partial Least Squares were used to screen the factors affecting the concentration of PAHs in residential dust. ResultsThe median concentration of ∑16PAHs in residential dust from 8 cities was 44.11 μg/g (0.04 - 355.79 μg/g). ∑16PAHs were found both higher in dust samples in heating season and from downwind households only in Mianyang (p < 0.05). The leading two sources of PAHs were combustion processes and automobile exhaust emissions based on four principal components that accounted for 74.29 % of the total variance. Indoor air environmental factors, household characteristics, and residents' behavioral lifestyles may be the influencing factors of residential dust PAHs. The carcinogenic risk of children aged 0 - 5 years, under the moderate exposure level of PAHs in residential dust, exceeded the acceptable level (10−5 - 10−4 for dermal contact and 10−6 - 10−5 for ingestion). ConclusionsThere was serious PAHs pollution in residential dust under actual living conditions in eight cities across China. More evidence-based measures were needed to control PAHs pollution to safeguard children's health according to appointed sources and influencing factors in residential dust.

Investigation of the Electronic and Vibrational Structures of the 2-Furanyloxy Radical Using Photoelectron Imaging and Photodetachment Spectroscopy via the Dipole-Bound State of the 2-Furanyloxide Anion.

The 2-furanyloxy radical is an important chemical reaction intermediate in the combustion of biofuels and aromatic compounds. We report an investigation of its electronic and vibrational structures using photoelectron and photodetachment spectroscopy and resonant photoelectron imaging (PEI) of cryogenically cooled 2-furanyloxide anion. The electron affinity of 2-furanyloxy is measured to be 1.7573(8) eV. Two excited electronic states are observed at excitation energies of 2.14 and 2.82 eV above the ground state. Photodetachment spectroscopy reveals a dipole-bound state 0.0143 eV below the detachment threshold and 25 vibrational Feshbach resonances for the 2-furanyloxide anion. The combination of photodetachment spectroscopy and resonant PEI yields frequencies for 18 out of a total of 21 vibrational modes for the 2-furanyloxy radical, including all six of its bending modes. The rich electronic and vibrational information will be valuable for further understanding the role of 2-furanyloxy as a key reaction intermediate of combustion and atmospheric interests.

Pressurised Chemical Looping Combustion (PCLC): Air Reactor design

Bioenergy combustion with Carbon Capture and Storage (BECCS) is a key technology to achieve carbon negative emissions power generation. This can be achieved by coupling the biofuels combustion with CO2 capture and storage (CCS). The lowest cost for CCS corresponds at the moment to the Chemical Looping Combustion (CLC) process. This can use biofuels which can be gaseous (biomethane, biogas or syngas etc.), liquid (biodiesel, bioethanol, biobutanol and pyrolysis oils etc.) or solids (wood dust, charcoal dust, wood chips, wood pellets etc.) While plant design with gaseous and liquid biofuels would be simpler, plants using solid biofuels and based on two couple fluidisd beds would need the use of a third reactor named carbon stripper. In the specific case if we plan to couple a CLC plant with a turbo expander (to achieve the high efficiencies of a combined cycle power plant) we have to work with pressurized reactors. However, there are some technical barriers to the coupling of a chemical looping combustor with a turbo expander, such as: the operation of the combustor in pressurised conditions; the inventory balance among reactors; elutriated particles reaching the turbo expander. This explaind why there is no commercial plant at the moment capable to do this. The aim of this paper is to present a model for the dimensioning of an air reactor to be coupled to a turbo expander of the power of about 12 MWe. Based on this, the air mass flow can be obtained and the geometric parameters can be calculated, to have an air velocity which is needed to achieve the fast fluidization regime and to ensure a high conversion rate as well as particles and heat exchage among air and fuel reactor.

Novel Scenedesmus obliquus algae biofuel emission and performance characterise in Si-DLC coated diesel engine

Investigation of the viability of providing biodiesel made from the algae Scenedesmus obliquus in a compression ignition (CI) engine. This research suggests Scenedesmus slick biodiesel (SOBD) as a possible source of energy, as it is found widely in marine, freshwater and aquaculture communities worldwide. SOBD was mixed with neat diesel fossil fuel at multiple volume ratios of 20 %, 30 %, 40 %, and its properties as a biofuel were analyzed according to ASTM standards. The characteristics study towards combustion, performance and emission of biofuel were analyzed by testing it on a single cylinder diesel engine at a 1500 rpm rated speed. The outcomes of the tests reveal that the efficiency of B20 (20 %SOBD + 80 % diesel) blend is comparable to pure diesel thermal efficiency, smoke, hydrocarbons and carbon monoxide. Still, the SOBD blend caused somewhat increased emissions of carbon dioxide and nitrogen oxides. At 100 % load, SOBD when compared with diesel achieves relatively lower cylinder pressures and lower heat release rates. In general, it is possible to deduce that the B20 blend (20 % SOBD 80 % diesel) will be a favourable feedstock variety that will be employed in unaltered combustion engines with minimal exhaust emissions.

Study on the explosion characteristics of propanal/air mixtures at elevated pressures

Propanal is a crucial intermediate speciates generated from the combustion of biofuels. To understand its formation pathways and optimize the clean combustion of biofuels, accurate determination of its laminar burning speed at engine-like conditions is essential. Additionally, propanal can be used to produce propionic acid by reacting with air under elevated pressures, which is a process that inherently poses a significant explosion risk. To address the above issues, the effects of initial pressures (0.1–1.0 MPa) and fuel concentrations (2.56–9.52%) on the explosion pressure and laminar burning speed of propanal/air mixtures were investigated. Results show that the relationship between the explosion pressure and fuel concentration was satisfactorily fitted by a cubic polynomial function. By comparing the laminar burning speed obtained using the constant volume method (CVM) and kinetic studies, the reliability of the kinetic model at elevated pressure was verified. According to the sensitivity analysis of elementary reactions affecting the flame temperature, the major elementary reactions affecting the combustion of propanal were analyzed. From fuel-lean to stoichiometric concentration, the combustion of propanal is dominated by the reaction kinetics of H2 and CO, while alkyl relevant mechanism controls the kinetics at fuel-rich conditions. At the fuel-lean conditions, recombination reactions were triggered during the collision of the excess oxygen molecules with reactive radicals. However, on the fuel-rich side, recombination reactions involving O2 progressively weakened. In addition to being affected by the equivalent ratio, elementary reactions are also profoundly influenced by the initial pressure. However, the effect of initial pressure on the elementary reactions is influenced by the fuel concentration. As the concentration of propanal is below the stoichiometric concentration, the sensitivity of elementary reactions increases gradually with the increasing initial pressures, while it no longer varies monotonously as the equivalence ratio reaches 1.5.

Study of The Pulmonary Function Test on Women, “The Domestic Biofuel (Wood) Users” in a Tribal Village of Paschim Medinipur, West Bengal, India

Air pollution is a widespread problem and its impact on the health of the human population is very high. This article provides an overview of the adverse effects of biofuel burning on women's health. The findings of this study were to determine the effect of the use of biofuel (mainly wood) in household works on lung function parameters of the exposed household workers (women). This study was conducted on 30 female subjects who use biofuel and collected the parameters height, weight, Body mass index (BMI), Saturation of peripheral oxygen (SpO2), Systolic and diastolic blood pressure, Peak expiratory flow rate (PEFR) was measured and was compared to the values of the different articles as reference values. Women, exposed to the biofuel smoke suffers from respiratory illness and have decreased PEFR values (l/min). To reduce pollutant exposures, we recommended the use of smokeless chullas as cleaner fuels such as kerosene, charcoal, remembering their poverty levels, as many studies show low pollution level from clean fuels. In the end, this study demonstrates the detrimental consequences of using biomass fuels, particularly wood, on the decline of pulmonary function.

Regional monitoring of biomass burning using passive air sampling technique reveals the importance of MODIS unresolved fires

Field-based sampling can provide more accurate evaluation than MODIS in regional biomass burning (BB) emissions given the limitations of MODIS on unresolved fires. Polyurethane foam-based passive air samplers (PUF-PASs) are a promising tool for collecting atmospheric monosaccharides. Here, we deployed PUF-PASs to monitor monosaccharides and other BB-related biomarkers and presented a dataset of 31 atmospheric BB-related biomarkers in the Indo-China Peninsula (ICP) and Southwest China. The peak concentrations of monosaccharides in the ICP occurred before monsoon season. The highest concentrations were in the eastern Mekong plain, while the lowest were along the eastern coast. BB-related biomarkers displayed elevated concentrations after April, particularly in the monsoon season; however, fewer active fires were recorded by MODIS. This revealed the importance of MODIS unresolved fires (e.g., indoor biofuel combustion, small-scale BB incidents, and charcoal fires) to the regional atmosphere. The PAS derived levoglucosan concentrations indicated that, with the inclusion of MODIS unresolved fires, the estimated top-down emissions of PM (4194–4974 Gg/yr), OC (1234–1719 Gg/yr) and EC (52–384 Gg/yr) would be higher than previous bottom-up estimations in the ICP. Future studies on these MODIS unresolved fires and regional monitoring data of BB are vital for improving the modeling of regional BB emissions.

Application of a physics-informed neural network to solve the steady-state Bratu equation arising from solid biofuel combustion theory

Physic-Informed Neural Networks (PINN) has attracted extensive attention in recent years. This method can use partial differential equations (PDE) or boundary value problems (BVPs) to describe the physics behind the desired problems and provide a solution without utilizing any data-driven techniques. This ability makes PINN applicable to a wide range of physical and engineering complex problems. In this paper, the PINNs is developed for solving Bratu equation arising from solid biofuel combustion theory. The governing BVP, is presented in a steady-state form. Assuming the answer to the problem in the form of a deep multilayer neural network and introducing it into the established BVP, a loss function is defined. Next, a discrete space of variables is developed by discretizing the range of the independent input variables, namely, location, and the loss function is minimized over all collocation points using the optimization algorithm. In this way, the proposed deep neural network is trained to estimate the response to the Bratu differential equation with the least possible error. Moreover, using a package of data collected from the real solutions to the problem, the accuracy of the developed PINN is evaluated. The results show that the trained PINNs could accurately estimate the answer to the problem and present the solution of governing BVPs systematically without any prior observation of the answer.