Fuel Gas Research Articles

Carbon dioxide capture in large-scale CCGT power plant from flue gases obtained from various fuel mixtures

In this study, the thermodynamic analysis of a combined cycle gas turbine integrated with post-combustion carbon capture and storage using the solvent method is performed. The syngas obtained from the gasification of sewage sludge is mixed with methane and nitrogen-rich natural gas fuels at different proportions, used in the gas turbine, and the properties of fuel and flue gases are analyzed. The flue gas obtained from the fuel mixture is passed through the post-combustion carbon capture and storage at various load conditions to assess the heat and electricity required for the carbon capture process. The solvent used for the carbon capture from flue gases enables CO2 capture with the high efficiency of 90%. With the calculated results, the load conditions of flue gas using fuel mixtures are identified, which reduces the heat and power demand of post-combustion carbon capture and storage and provides the possibility to achieve neutral emission. The impact of selected operating conditions of post-combustion carbon capture and storage on the CO2 emission reduction process and on the power plant performances is investigated. Considering the factors of electricity generation, energy efficiency, heat supply to the consumers, operating load of post-combustion carbon cap-ture and storage and CO2 emission, the 50% mixture of syngas with both fuels performs better. Also, the use of a mixture of 2-amino-2methyl-1-propanol and piperazine with reboiler duty 3.7 MJ/kgCO2 in post-combustion carbon capture and storage slightly enhanced the performance of the power plant compared to the use of monoethanolamine with reboiler duty 3.8 MJ/kgCO2.

Exploring the influence of metal oxides on the pyrolytic behavior and decomposition mechanism of the green gas generating agent 5-Aminotetrazole

5-Aminotetrazole (5AT) is widely used as a green gas-generating agent in fire extinguishers, but it exhibits low combustion stability. To enhance its combustion rate and modify gas production performance, this study investigated the catalytic effects of adding different metal oxides (Bi2O3, PbO, TiO2, and CoO) on its pyrolysis process and decomposition mechanism. The pyrolysis behavior and pyrolysis products of 5AT were studied by simultaneous thermal analyzer (thermogravimetry - differential thermal analysis, TG-DTA) and TG-FTIR/MS (mass spectrometry and fourier transform infrared spectroscopy) hyphenated instrument. Isoconversional methods were used to calculated kinetic parameters, and reaction mechanism was also speculated by combining the experimental and calculational results. The experimental results indicated that Bi2O3, PbO, TiO2 and CoO have minimal impact on the ring opening reaction process of 5AT, but they catalyzed the polymer decomposition process of 5AT, especially CoO. Consequently, the addition of metal oxides as catalysts to 5AT holds significant potential for improving its thermal safety and enhancing its suitability as a solid propellant gas generator.

Alternative Technology Solution for Cooking: Compact Biogas Digester

This study is undertaken to prepare an alternative technology solution for cooking and to implement the design and set - up an operational of an onsite bio digester that will generate sufficient methane gas for cooking and probably other applicable uses. The biogas digester is simple to operate for everybody and effective option to save cost on power. It was found that a unit no smaller than 200 liters was needed to meeting the feedstock unit that gives a 2 hour per day cooking duration for a gas cooker run off one of these unit. Bio digester technology: Cow manure and kitchen waste feed produces more methane gas, and the reaction is completed in 7 days.

A novel PEMFC-GT-ST power generation system employing supercritical water gasification of coal for enhanced hydrogen production

This study presents an innovative coal-fired power generation system that integrates a Proton Exchange Membrane Fuel Cell (PEMFC), Gas Turbine (GT), and Steam Turbine (ST) with a supercritical water gasification (SCWG) process designed to efficiently convert coal into hydrogen. A pivotal feature of this system is the first-time integration of advanced two-step SCWG technology with PEMFC, which significantly boosts hydrogen yield, thereby elevating overall efficiency. By effectively addressing the thermodynamic limitations of the Carnot cycle, the proposed system achieves an impressive coal-to-electricity conversion efficiency of 51.61%. Economic viability is demonstrated through a competitive levelized cost of energy (LCOE) of $0.052 per kWh and a rapid payback period of approximately 2.87 years. Furthermore, the study analyzes the impact of various operational parameters—such as coal feed capacity, water-to-coal ratio, operating temperatures of the PEMFC, fuel utilization rates, airflow, and hydrogen bypass flow—on system performance. The findings not only advance the efficiency of coal-to-electricity conversion but also contribute valuable insights to the evolution of sustainable coal-fueled power generation technologies.

Optimizing Syngas Production from Municipal Solid Waste Gasification: A Dual Reactor Fluidized Bed Study with Steam and CO2 as Gasification Agents

The escalating production of municipal solid waste (MSW) poses significant environmental and health hazards due to air, water, and soil pollution. Utilizing MSW as an energy source through gasification offers a promising solution to mitigate these impacts. This study investigates the gasification of MSW using a Dual Reactor Fluidized Bed, a thermal technology that converts solid substrates into usable gaseous fuels. The primary objective is to optimize the quality of the produced syngas by employing specific gasification agents, namely steam and CO2, and their mixtures. The research examines the effect of these agents on H2/CO ratios across a wide range of low operating temperatures, from 400°C to 700°C, using silica sand as a heat conduction medium between interconnected combustion and gasification reactors. The results demonstrate that the composition of syngas is strongly influenced by gasification temperature fluctuations. Increasing temperatures from 400°C to 700°C correlate with higher concentrations of CO and H2 in the syngas. The use of steam as a gasification agent yields H2 concentrations up to 25%, while transitioning from steam to CO2 leads to a substantial increase in CO composition, reaching 22.73%. Further analysis reveals that the H2/CO ratio decreases from 1,78 with steam and 0.64 with CO2, highlighting the crucial role of gasification agents in syngas quality. This study underscores the potential for optimizing syngas production from MSW by manipulating gasification temperatures and transitioning between different agents (steam, CO2, and their mixtures), resulting in an overall increase in the calorific value of the produced gas. These findings emphasize the opportunity to transform substantial environmental challenges associated with MSW into promising sustainable energy solutions through advanced gasification technologies.

The Influence of Gas Fuel Enrichment with Hydrogen on the Combustion Characteristics of Combustors: A Review

Hydrogen is a promising fuel because it has good capabilities to operate gas turbines. Due to its ignition speed, which exceeds the ignition of traditional fuel, it achieves a higher thermal efficiency while the resulting emissions are low. So, it was used as a clean and sustainable energy source. This paper reviews the most important research that was concerned with studying the characteristics of hydrogen combustion within incinerators and power generation equipment, where hydrogen was used as a fuel mixed with traditional fuel in the combustion chambers of gas turbines. It also includes an evaluation of the combustion processes and flame formation resulting from the enrichment of gaseous fuels with hydrogen and partial oxidation. A large amount of theoretical and experimental work in this field has been reviewed. This review summarizes the predictive and experimental results of various research interests in the field of hydrogen combustion and also production.

Adoption of clean energy cooking technologies in rural households: the role of women

Abstract Ensuring energy access for rural households is crucial for global sustainable development. Technologies like liquefied petroleum gas, biogas, and efficient cookers are touted as solutions, yet their adoption remains limited despite their potential health, economic, and environmental benefits. We conducted a meta-analysis of 50 studies in developing countries, integrating contextual factors to explore gender and other determinants impacting rural energy transition. Our findings underscore socioeconomic status, social capital, environmental concerns, and gender dynamics as pivotal factors. Notably, women's involvement boosts adoption rates by 7.90 per cent, yet cultural barriers often sideline them from these processes. Thus, our recommendations stress addressing women's roles as energy technology users to foster inclusive energy transitions.

Electrochemical Impedance Spectroscopy Study of Ceria- and Zirconia-Based Solid Electrolytes for Application Purposes in Fuel Cells and Gas Sensors

In this study, the structural and electrochemical properties of commercial powders of the nominal compositions Ce0.8Gd0.2O1.9, Sc0.1Ce0.01Zr0.89O1.95, and Sc0.09Yb0.01Zr0.9O1.95 were investigated. The materials are prospective candidates to be used in electrochemical devices, i.e., gas sensors and fuel cells. Based on a comparison of the EIS spectra in different atmospheres (synthetic air, 3000 ppm NH3 in argon, 10% H2 in argon), the reactions on the three-phase boundaries were proposed, as well as the conduction mechanisms of the electrolytes were described. The Ce0.8Gd0.2O1.9 material is a mixed ionic–electronic conductor, which makes it suitable for anode material in fuel cells. Moreover, it exhibits an apparent and reversible response for ammonia, indicating the possibility of usage as an NH3 gas-sensing element. In zirconia-based materials, electrical conduction is realized by oxygen ion carriers. Among them, the most promising from an applicative point of view seems to be Sc0.09Yb0.01Zr0.9O1.95, showing a high, reversible reaction with hydrogen.

Hydrogen enriched natural gas-fueled solid oxide fuel cells supported by Ni-Cu co-doping CeO2-δ catalyst-modified finger-like pore anode

Hydrogen blending in natural gas pipelines is one of the key technologies to realize the long-distance hydrogen transmission, which facilitates the large-scale hydrogen utilization. Solid oxide fuel cells can directly use hydrogen enriched natural gas (HENG, with 20 % H2) to generate electricity without separating and purifying the hydrogen, which enables the efficient conversion of hydrogen energy. In this work, finger-like pore anodes and Ni0.05Cu0.05Ce0.9O2-δ (NCCO) catalyst are prepared to address the need for anode performance and stability with hydrogen-doped natural gas fuels. The results show that NiCu@CeO2 precipitates NiCu nano-alloys on the surface after reduction treatment, which is beneficial for the anode activity. With NCCO catalyst, the maximum power densities of the single cells are 970 mW cm−2 and 700 mW cm−2 at 750 °C under wet H2 and HENG fuel atmospheres, respectively. At 750 °C, the methane conversion is as high as 46 %. More importantly, the single cell can run smoothly for 150 h, with the constant voltage (0.8 V) discharge and HENG as fuel gas. Our results confirm that the synthesized NCCO catalysts have excellent ability to catalyze CH4 and carbon resistance.

Environmental impact of pressurised metered dose inhalers versus dry powder and soft mist inhalers at a tertiary Melbourne hospital.

The carbon footprint of devices to deliver inhaled respiratory medications has come into focus as climate change has been identified as a worldwide emergency. Metered dose inhalers (MDIs) contain hydrofluorocarbons that have significant global warming potential compared to dry powder inhalers (DPIs) and soft mist inhalers (SMIs), which do not use a propellant gas. A 12-month pharmacy inpatient dispensing audit demonstrated that inpatient MDI use significantly outweighed that of DPIs and SMIs and accounted for approximately 99% of inhaler-related greenhouse gas emissions at our hospital.

Effects of different gas energy shares on combustion and emission characteristics of compression ignition engine fueled with dual-fossil fuel and dual-biofuel

This study systematically investigates the energetic and environmental performance of a four-cylinder compression ignition (CI) engine fueled by gaseous and liquid dual-fuel (D-F), utilising various combinations of fossil fuels and biofuels. Fossil diesel or pure hydrotreated vegetable oil (HVO) – new generation biodiesel was used as the pilot fuel to initiate ignition of the gaseous fuel. The gaseous fuels used were natural gas (NG) and simulated biogas (BG) composed of 60 % NG and 40 % CO2 by volume, injected into the intake manifold at varying gas energy shares (GES) of 40 %, 60 %, and 80 %. Reference values were provided from conventional combustion of diesel fuel and HVO. This study used numerical simulations to examine indicators of combustion, such as ignition delay, premixed combustion phase, diffusion combustion phase, and subsequent combustion phases, across diverse fuel combinations. Within lean dual-fuel mixtures, when the gaseous fuel remained below the flammability threshold, the peak pressure was diminished, the rate of pressure rise was lowered, and the combustion process decelerated, facilitating a faster transition to the diffusion phase. As the engine load and GES increased, the excess air ratio decreased, bringing the air-fuel mixture closer to the flammability limit, which in turn altered the combustion characteristics and engine performance trends. Combustion with increasing BG content showed partial similarities to that of NG, though the high CO2 content in biogas was found to suppress combustion, functioning similarly to an exhaust gas recirculation. The study also compared brake thermal efficiency (BTE), as well as specific emissions of CO, HC, NOX, CO2, and smoke for the D-F engine operation against pure diesel and HVO at different loads and GES levels. Additionally, an overlimit function was used to assess the emission levels of D-F engines with reference to emission limits.

A concise review towards a novel target specific multi-source unsupervised transfer learning technique for GDP estimation using CO2 emission data

Though economic growths of most of the nations have seen exponential rise due to industrialization, it has also caused proportional increase in their carbon emissions. This paper exploits this proportionate relationship of carbon emission with GDP to predict the per-capita GDP of those nations whose GDP values are missing in the world bank database. The reason behind the same was, those countries were either war-torn or politically isolated/unstable. To achieve the objective of predicting the missing GDP values of those countries from their carbon emissions, this paper exploits the non-linear relationship among the carbon emissions from solid fuels, liquid fuels, and gaseous fuels. It is so because even the differential utilization of these fuels impact economy differently. Use of traditional solid fuel for cooking points toward energy poverty, and access to clean cooking gas indicates higher living standard. However, the available data from the war-torn or isolated countries are very little, and hence insufficient for building a robust predictive machine learning model. So, this paper employs multi-source unsupervised transfer learning to precisely estimate the missing per-capita GDP of those nations. It suitably enlarges the training domains for the prediction models to be more robust. We empirically evaluate the proposed methodology for different regression techniques to estimate the missing GDP values of eleven different nations belonging to diverse strata of economies viz. developed economies, developing, and/or least developing economies. Proposed methodology profoundly improves the prediction preciseness of these regression techniques in estimating the missing per-capita GDP of the considered nations.

Prenatal Exposure to Source-Specific Fine Particulate Matter and Autism Spectrum Disorder.

In this study, associations between prenatal exposure to fine particulate matter (PM2.5) from 9 sources and development of autism spectrum disorder (ASD) were assessed in a population-based retrospective pregnancy cohort in southern California. The cohort included 318,750 mother-child singleton pairs. ASD cases (N = 4559) were identified by ICD codes. Source-specific PM2.5 concentrations were estimated from a chemical transport model with a 4 × 4 km2 resolution and assigned to maternal pregnancy residential addresses. Cox proportional hazard models were used to estimate the hazard ratios (HR) of ASD development for each individual source. We also adjusted for total PM2.5 mass and in a separate model for all other sources simultaneously. Increased ASD risk was observed with on-road gasoline (HR [CI]: 1.18 [1.13, 1.24]), off-road gasoline (1.15 [1.12, 1.19]), off-road diesel (1.08 [1.05, 1.10]), food cooking (1.05 [1.02, 1.08]), aircraft (1.04 [1.01, 1.06]), and natural gas combustion (1.09 [1.06, 1.11]), each scaled to standard deviation increases in concentration. On-road gasoline and off-road gasoline were robust for other pollutant groups. PM2.5 emitted from different sources may have different impacts on ASD. The results also identify PM source mixtures for toxicological investigations that may provide evidence for future public health policies.

Experimental Evaluation of Diesel Engine Performance using Producer Gas and Conventional Fuel: A Comparative Study

Experimental Evaluation of Diesel Engine Performance using Producer Gas and Conventional Fuel: A Comparative Study

DEVELOPMENT OF THE THEORY OF GAS FUEL COMBUSTION TAKING INTO ACCOUNT MODERN KINETIC MECHANISMS OF COMBUSTION

An actuality of modernizing advancement the modern adopted combustion theory is due to a significant change in the composition of fuels at the market of developed countries by rejection of basic mineral (organic) fuels (fossil fuels), which have been used in the world for 250 years. The transformation of traditional fuels’ orientation towards an application of carbon-free fuels, primarily to hydrogen and its mixtures with natural gas. Each way of mentioned activity is connected with to ensure an environmental decarbonisation. Criteria for evaluating the CO2 emissions by fuels’ choice and selection have been proposed while numerical calculations of the specific CO2 content in the combustion products of the hydrocarbon-hydrogen mixture jʹ and j have been evaluated. It is possible to reduce these values when adding the shared H2 in the fuels (m3 CO2/ MJ; kg CO2/ MJ). Considering the combustion process in combustion systems (combustion chambers, boilers, furnaces) at constant pressure (p =const, dp =0 — isobaric process), the enthalpy of the reactants’ flow of the mixture (total (chemical) enthalpy I) can serve as a measure of the specific energy of the reacting mixture. An approach is proposed, according to which the main equations of heat and mass transfer in the torch (premixed flame) are composed basing upon the principle of conservation the total (chemical) enthalpy representing energy as basic function. The basic approach to the development of a modern combustion theory is focused on the concept of T. von Karman, according to which the combustion process is considered as “aerothermochemistry”, i.e. the description of physical and chemical processes is based on the combination of heat and mass transfer equations with chemical kinetics’ equations. At the current period, the problem of chemical kinetics (burning process) is considered through the combustion mechanisms of basic fuels, which consist of a large number of equations for molecules and particles involved in process at various stages of the combustion — from the preheating of the reaction mixture and through the stage of ignition (or self-ignition) — to the final temperature of flue gases. The laminar combustion velocity SL is a determinative characteristic of the combustible properties of gas fuels and, accordingly, of the safety restrictions by the fuel choice. Quantitative values of SL for the separate basic fuels, including the hydrogen, both the organic (fossil fuels) and alternative ones could be differed by an order of magnitude and more. The problem of estimable forecasting the SL value provides an option of the composition of the fuel-oxidant mixture in the industry, power and municipal energetics. The SL value’s prediction makes an especially important action at the current stage of modelling completion with an account of the global warming and by preventing an excess of CO2 emissions, including involvement of hydrogen-containing gases by substitution the carbon-friendly fuels, firstly the fossil fuels. The contemporary theory of combustion has been developed by extensive use the adequate kinetic mechanism GRI-Mech 3.0, the universality of which has been confirmed by our calculations of SL values for a wide range of the gas fuels — from methane CH4 to hydrogen H2 and their mixtures. An advanced modern theory of combustion using the adequate and approved GRI-Mech 3.0 combustion kinetic mechanism has been developed. The universality of this mechanism is confirmed by our calculations of SL values for a wide range of gaseous fuels — from methane CH4 to hydrogen H2 and their mixtures (mixed gases MG). For further analysis and development, the model of combustion in the reacting flow by Y.B. Zeldovich and D.A. Frank-Kamenetsky was used, considering the transfer processes of total enthalpy I as the energy characteristic of the combustible mixture. The kinetic component (on the example of natural gas) is taken into account using the combustion mechanism for GRI-Mech 3.0. The latter summarizes the combustion process of through 325 constituent reactions for 53 components. The adequacy of the combustion model proposed in the paper is confirmed by numerical examples of the coincidence of numerical SL values: ours — calculated; literary — experimental. The validity of experimental values of SL is provided by the use of different methods of measuring the SL. Calculations of the specific total enthalpy I of the reacting mixture along the length x º l (thickness of the front for a homogeneous flame in a one-dimensional formulation) have been performed as a result of researches confirmed the initial position: I(x) = const with deviations for CH4 +7 % / –2 %; for H2 +9,2 % / –2,8 % in relation to the heat of combustion. Bibl. 52, Fig. 9, Tab. 3.

Liquid fuel cloud detonation and droplet lifetime

The structures and mechanisms of aerosolized liquid-fuel cloud detonations are studied in a detonation facility using simultaneous high-speed optical diagnostics. The characteristic length scale of the droplet lifetime in liquid fuel detonations is not well predicted by established breakup and evaporation models, whereas it captured by calculations of the evaporation time of the droplet cloud. Novelty and significance statementDetonation research has mostly focused on gaseous fuels with limited investigations of purely liquid fueled detonations. This research explores the characteristic length scales of aerosolized liquid fuel droplets’ lifetime showing it does not scale with established breakup and evaporation models. It scales well with the evaporation time of child droplet clouds, highlighting the significance.

Gasification of multi-layer porous fuels in low-temperature gas generator for flying vehicle

The paper is aimed at investigating the influence of porous fuel layering on the operating regimes and performance of a low-temperature gas generator for high-speed flying vehicles equipped with a ramjet engine. The gas generator consists of a propellant and a porous fuel arranged sequentially to generate hydrocarbon gases that cool the engine before burning in the combustion chamber. In this paper, using a novel numerical model, gasification of multi-layer solid porous fuels consisting of polymethylmethacrylate (PMMA) and polyethylene (PE) is studied for various volume contents and relative arrangements of fuel parts. It is shown that during the gasification of the multi-layer fuels, several gasification waves can simultaneously occur in the gas generator. The operating time of the gas generator depends on the relative sizes and relative location of the PMMA and PE layers, and an increase in the number of layers leads to a decrease in the influence of their relative arrangement on the process. Thus, during the gasification of two-component multi-layer solid porous fuel, the composition of this fuel, i.e., the relative sizes of the layers and their relative arrangement, can be the control parameter that allows one to choose the desired characteristics of the gasification process.

Research on 2D/2D Au/g-C3N4 electron donor/acceptor strategy for highly efficient CO2 photoreduction

Utilizing CO2 photoreduction technology to convert CO2 into carbon-based gaseous fuels represented an effective strategy for maintaining sustainable development on Earth. Addressing the issue of poor electron separation efficiency in pure g-C3N4, an innovative approach was taken to construct a two-dimensional/two-dimensional (2D/2D) structure using Au nanosheets (Au NSs) combined with g-C3N4 nanosheets (CN NSs) for CO2 photoreduction. The CO and CH4 yields converted by CO2 photoreduction over Au/CN composite (15AC) with optimized proportion were about 44.76 and 32.12 μmol g−1 h−1 under UV–Vis light irradiation, respectively. Photoelectrochemical experiments revealed that the modification of CN NSs with Au NSs significantly improved the separation efficiency of photogenerated carriers at the 2D/2D interface, while enhancing the CO2 adsorption ability of pure CN NSs. Density Functional Theory (DFT) calculations were employed to analyze the electron transfer pathways at the 15AC interface and the formation of a built-in electric field, which concurrently confirmed that the electron donor–acceptor relationship accelerated the transfer of photogenerated electrons from CN NSs to Au NSs. In-situ FTIR and 13CO2 isotope calibration experiment were utilized to probe the CO2 photoreduction process. Finally, the possible electron donor–acceptor enhanced mechanism at the 2D/2D Au/CN interface for enhancing the CO2 photoreduction reaction were discussed.

Impact of CO2 on the Pyrolysis of Mixed Polymer Wastes into Combustible Fuel: A Case Study for Footwear Waste

Plastic waste is a promising resource for producing liquid fuels that can be integrated into existing hydrocarbon infrastructures. However, the heterogeneous nature of plastic-derived liquid fuels limits direct application in internal combustion engines, necessitating their refinement into a usable form. To address these issues, this study explored the enhancement of combustible gaseous fuels derived from plastic waste, footwear waste, as a viable alternative. This approach involves the introduction of carbon dioxide as a reactive feedstock during the pyrolysis process. Analytical techniques were employed to precisely determine the types and compositions of four polymers present in footwear waste. The compositional matrices of the primary pyrogenic products were also identified. However, incorporating carbon dioxide into pyrolysis leads to its interaction with volatile compounds, converting them into lighter gaseous products, particularly carbon monoxide. The homogeneous reactivity of carbon dioxide was further enhanced by the application of heat and a nickel-based catalyst. The gaseous product yield from catalytic pyrolysis in the presence of carbon dioxide increased proportionally with the test temperature. Specifically, the use of carbon dioxide led to a 1.92-fold increase in gaseous product yield at 700 ˚C, in reference to the results from nitrogen. This study demonstrates a technical advancement in pyrolytic valorisation of footwear waste by incorporating carbon dioxide and provides a detailed investigation into its mechanical role in maximising the production of combustible gaseous fuels.

Gaztronomy: cuisine and modernity in 1930s Lisbon

ABSTRACT The progressive electrification of kitchens that still place gas cookers center stage raises important questions about the relationship between energy, technology, and culinary practices that emphasize the relevance of more deeply understanding past transitions. This research explores material culture and culinary technology, examining the link between culinary practices and the shift to gas usage in Lisbon households during the 1930s. Seeking to understand this Gaztronomy, we analyzed the programs and recipes from the cooking courses sponsored by the main Lisbon gas utility company during the period 1931–1939, considering aspects such as the stages in the energy transition, diffusion of gas stoves and the characteristics of Portuguese culinary literature. The nearly four hundred recipes presented in the cooking lessons featured in these materials highlight the association between the cosmopolitan nature of the proposed selection and the modernity of gas cooking, leading to an attempt to understand the role of this “modern energy” as an inducer of new culinary practices in the domestic and family sphere. Culinary expertise proved to be an appealing and powerful tool for overcoming resistance to change and consumer anxieties over adopting a new fuel, indeed, as observed by the main Lisbon supplier at that time.