Methane Research Articles

Environmental Issues and Sustainable Development: The Global and Indian Perspective

The paper aims to discuss about the historic trend of global warming and greenhouse gas emission since the late 18th century due to widespread use of fossil fuels and industrial processes. This paper provides an overview of rise of greenhouse gases such as carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), nitrogen trifluoride (NF3), and other gases and their contribution in warming the global temperature in the prior and later period of industrial revolution. Highlighting the relationship between greenhouse gas emission and human activities that has resulted in significant challenges to the global ecosystems that includes severe and frequent heatwaves, altered precipitation patterns, melting of glaciers, rising of sea level, along with the backward economies facing disproportionate risks and challenges in water resources, food scarcity due to draughts and high temperature as well as health issues due to low productivity and slow development. Hence, considering the problems faced by the societies worldwide, it is essential to have cooperative strategies with local, national and international agencies to implement effective mitigation measures and adaptation schemes so that the societies could foster resilience, mitigate risks and work towards a sustainable future.

Global Warming Mitigation Innovation Through Household Waste Management Becomes Eco-Enzyme: A Review

The dumping of fruit and vegetable waste into landfills contributes to an increase in methane gas that contributes to global warming. Waste materials in the form of fruits and vegetables can be used and processed into eco-enzymes. Fermented waste enzymes have a variety of benefits and add value to materials that have been tended to be wasted. This environmentally friendly enzyme has been utilized ranging from disinfectants, floor cleaners, dishwashers to liquid organic fertilizers. The production of eco-enzymes in addition to being able to reduce the volume of household waste, also contributes to the reduction of methane gas. During the fermentation process produces O3 (ozone) which is beneficial in maintaining ozone content in the atmosphere. This means that eco-enzyme production becomes an innovation in mitigating global warming from the household level. The manufacture of eco-enzymes is an effort to provide economic value to waste that has a positive impact on the environment and is a step to maximize the utilization of natural resources better known as circular economies. The advantages of eco-enzyme production in the short term are the ability to maximize raw materials and provide economic value and reduce the cost of handling household waste.

Photocatalytic activity of TiO2:TiN nanocomposite films prepared by DC reactive sputtering technique for air purification

This study concerns the production of advanced materials and a novel technique for enhancing photocatalytic efficiency, focusing specifically on the purification of air contaminated with methane gas. Titanium dioxide:Titanium nitride (TiO2/TiN) nanocomposite films were prepared by dc reactive magnetron sputtering of highly-pure titanium sheet in presence of oxygen and nitrogen as reactive gases with optimized mixing ratios to produce the composite structures. The structural, morphological, and optical characteristics of the prepared nanocomposites were determined and analyzed. The primary goal of this study was to enhance the photocatalytic activity of such nanocomposites against methane gas pollution. It is observed that increasing the nitrogen content in the TiO2:TiN nanocomposite structure led to notable improvements in photocatalytic efficiency. Specifically, when these nanocomposites were subjected to a UV light, they exhibited enhanced photocatalytic activity in the removal of methane gas from the surrounding air, which demonstrates a direct correlation with increased nitrogen (N) content in the composite structure. These nanocomposites are reasonably promising in removing harmful gases and pollutants present in indoor and outdoor environments. This exploration not only sheds light on the remarkable potential of TiO2:TiN nanocomposites for air purification but also highlights the importance of innovative techniques, such as dc reactive magnetron sputtering in the field of materials science and engineering as well as in environmental remediation.

Phase equilibrium data for semiclathrate hydrates formed with n-propyl, tri-n-butylammonium bromide and tri-n-butyl, n-pentylammonium bromide under methane, carbon dioxide and nitrogen gas pressure

Semiclathrate hydrates are water-based materials formed from aqueous solutions of ionic substances. To enhance the gas capture performance of these materials, it is necessary to direct focus on the cation, which is a key part of construction of the hydrogen-bonding framework. In this paper, we focus on the partly-asymmetric cations, i.e., the n-propyl, tri-n-butylammonium bromide (N3444Br) and tri-n‑butyl, n-pentylammonium bromide (N4445Br), which are yet to be subjected to gas hydrate formation. The three phase equilibrium (gas–hydrate–liquid) conditions for the systems of (N3444Br or N4445Br) + H2O + (CH4, CO2 or N2) in the range of the pressure and mass fractions of the aqueous solutions between 1 and 11 MPa and 0.10–0.40, respectively, are reported. In all the systems, the semiclathrate hydrates were successfully formed under gas pressure. It was demonstrated that both the N3444Br and N4445Br salts promoted hydrate formation under these gases, while in the case with lean aqueous solutions N3444Br acted as an inhibitor of methane hydrate formation in pure water system. The present data are compared with the literature data, and the effect of the side chain length on the phase behavior of the semiclathrate hydrate phase is discussed.

Methylotrophic substrates stimulated higher methane production than competitive substrates in mangrove sediments

Although mangrove forests can uptake atmospheric CO2 and store carbon as organic matter called “blue carbon”, it is also an important natural source of greenhouse gas methane. Methanogens are major contributors to methane and play important roles in the global carbon cycle. However, our understanding of the key microbes and metabolic pathways responsible for methanogenesis under specific substrates in mangrove sediments is still very limited. Here, we set an anaerobic incubation to evaluate the responses of methanogens in mangrove sediments from South China to the addition of diverse methanogenic substrates (H2/CO2, acetate, trimethylamine (TMA), and methanethiol (MT)) and further investigated the dynamics of the whole microbial community. Our results showed that diverse substrates stimulated methanogenic activities at different times. The stimulation of methanogenesis was more pronounced at early and late periods by the addition of methylotrophic substrates TMA and MT, respectively. The amplicon sequencing analysis showed that genus Methanococcoides was mainly responsible for TMA-utilized methanogenesis in mangrove sediment, while the multitrophic Methanococcus was most abundant in H2/CO2 and MT treatments. Apart from that, the bacteria enrichments of Syntrophotalea, Clostridium_sensu_stricto_12, Fusibacter in MT treatments might also be associated with the stimulation of methane production. In addition, the metagenomic analysis suggested that Methanosarcinaceae was also one of the key methanogens in MT treatments with different genomic information compared to that in TMA treatments. Finally, the total relative abundances of methanogenesis-related genes were also highest in TMA and MT treatments. These results will help advance our understanding of the contributions of different methanogenesis pathways and methanogens to methane emissions in mangrove sediments.

Evaluation of municipal solid waste characterization and landfill gas power plant electrical energy production efficiency during COVID-19 pandemic

Due to the COVID-19 pandemic, the amount and types of municipal solid waste (MSW) have dramatically changed. This study focuses on characterizing the MSWs in the regular waste storage facility (RWSF) in Izmir, Turkey, and determining the electrical energy that can be produced by the landfill gas power plant (LFGPP) established to convert the waste to energy (WtE). Therefore, firstly the MSWs were characterized. After, the amount of produced methane (CH4) gas was determined using Landfill Gas Emissions Modeling (LandGEM). The amount of generated electricity, the dependent variable in the LandGEM model, was most influenced by the quantity of MSW, garbage disposal processes, and maintenance times of gas generators, while other factors remained relatively weak. This situation has also been confirmed in the field. During the COVID-19 pandemic, the increase in MSW was 9.8% in 2020 and 10.3% in 2021. Kitchen waste containing the highest CH4, accounted for 38% of the MSW characterization. The amount of generated electricity in the LandGEM model was 237 GWh in 2020 and 245 GWh in 2021. While these values could be achieved by 11.25% in 2020 due to various system and field failures, they reached 79.73% in 2021 due to system and field improvements.

Distributed Regime and Swirler Effects on Methane and Coke Oven Gas Combustion Characteristics

Distributed Regime and Swirler Effects on Methane and Coke Oven Gas Combustion Characteristics

Calculation of coal cleats spacing for methane degassing by image processing

Coal bed methane is one of the clean energy sources in the world. Methane molecules are confined inside the pores of coals and when the gas drainage wells are drilled into the coal seams, due to the resulted pressure difference. Coal cleats are spread all over the coal seam as face and butt cleats and play an essential role in the methane gas drainage operation from coal mines. Calculating the coal cleats spacing makes great help in modeling the amount of emitted gas followed by calculating the spacing of gas suction wells. Furthermore, the time required for gas drainage will be determined. Computer-based image processing technique has been utilized to identify the cleats spacing. In this study, three-dimensional computed tomography scan images were prepared for coal samples from Tabas Coal Mine in Iran. Computer-based image processing technology was conducted to determine the coal cleats. Their spacing was then calculated. Based on the results obtained using image processing with computer, the average distance between face cleats was 20 to 30 mm and the distance between butt cleats was 15 to 25 mm. The results of this study are used to modeling the amount of methane gas in the coal cleats. Based on this modeling, the amount of released gas and the distance between the wells can be designed.

Comparative analysis of methane and natural gas pyrolysis for low-GHG hydrogen production

Methane pyrolysis is emerging as an attractive clean hydrogen production method. As its commercialization proceeds, the pyrolysis of natural gas (NG) becomes pertinent. In this work, the decomposition of pure methane and a realistic NG mixture are compared experimentally and numerically. Methane and NG pyrolysis are performed between 600 and 1200 °C over a fluidized bed of carbon particles heated by microwaves. Experimentally, no conclusive difference is observed in methane conversion between methane and NG pyrolysis. Numerically, the methane conversion rate is 8.5% higher for NG at 950 °C. The difference diminishes past 950 °C, becoming 0 past 1050 °C. The simulations showed that the enhanced methane decomposition in NG pyrolysis is due to an attack on methane by radicals generated during ethane and propane decomposition. The CO2 in our NG mixture decomposes into CO. This work validates the longstanding use of methane pyrolysis as a surrogate for NG pyrolysis.

Assessing Greenhouse Gas Emissions and Methane Production During Post-Landfill Maintenance in Kish Island: A LandGEM Simulation Approach

Background: Municipal solid waste (MSW) landfills are significant contributors to the emission of greenhouse gases, particularly methane, during the breakdown of waste materials. Researchers have undertaken extensive investigations into quantifying methane emissions from landfills, utilizing various methodologies beyond reliance on the LandGEM model. Numerous studies have underscored the efficacy of this model in predicting methane generation and exploring its utility in activities such as energy generation and emission mitigation strategies. Objectives: Municipal solid waste landfills are vital contributors to greenhouse gas emissions, notably methane, during waste decomposition. Significant research has focused on estimating methane output from landfills, utilizing various approaches beyond the LandGEM model. Studies highlight the model's potential in assessing methane generation and its relevance to activities like energy generation and emission management. Methods: The LandGEM simulation model is employed to forecast future waste generation and provide valuable insights into the environmental consequences of landfill management on the island. By analyzing population data and waste generation statistics from 2023 to 2042, the study utilizes the LandGEM software to estimate methane emissions, incorporating site-specific data and waste composition analysis. Results: The findings reveal that 36% of the total waste on Kish Island consists of putrescible material, with food waste being a significant component. Over the study period, approximately 1,282,637 tons of waste are projected to be disposed of in the Kish landfill. The LandGEM model predicts the highest landfill gas emission in 2043, primarily methane, along with carbon dioxide and non-metallic organic compounds. The estimated quantities for these gases in 2043 are 5.415E+03, 1.486E+04, and 2.327E+02 metric tons, respectively. Conclusions: This research highlights the importance of tailored waste management strategies to mitigate environmental impacts and emphasizes the need for efficient gas collection systems. A proposed gas collection system combining vertical wells, horizontal trenches, and under-membrane pipes is discussed to enhance efficiency and reduce environmental risks. The study provides valuable insights into waste management and landfill gas emissions on Kish Island, underscoring the significance of accurate emission prediction and effective management to minimize environmental consequences and optimize the utilization of renewable energy resources.

Optimal planning of integrated electricity-natural gas distribution systems with hydrogen enriched compressed natural gas operation

In future integrated electricity-natural gas distribution systems (IEGDS), hydrogen and methane converted from excessive renewable generation will be mixed with natural gas to form hydrogen enriched compressed natural gas (HCNG) for fewer carbon emissions. Consequently, optimal planning of the HCNG-integrated IEGDS plays an essential role in increasing the economy and technical benefits. However, integrating HCNG operation into the planning of IEGDS still has many challenges, such as unrealistic modeling, nonlinear constraints, and the potential risk of voltage violations. The purpose of this paper is to develop a tractable optimization model for planning and operation of the HCNG-integrated IEGDS, aiming to minimize the investment and operating cost, reduce the voltage violation, and improve the renewable power penetration rate. To achieve this, a bilevel optimization model is developed for optimal planning of wind turbines and soft open points (SOPs) in the IEGDS considering comprehensive HCNG operation, in which both hydrogen and methane injection are considered and optimized for different system operation scenarios. Furthermore, the proposed nonlinear model is reformulated to a tractable bilevel mixed-integer second-order cone model using several reformulation techniques and solved by the reformulation and decomposition algorithm. Case studies, performed using the publicly available datasets, are conducted to demonstrate the economic and technical improvement by implementing the proposed planning model. The annual planning results show that incorporating the coordination between SOPs and methane injection results in a 6.77% reduction in investment cost, a 22.64% reduction in operating cost, a 62.69% decrease in voltage violation, and a 23.58% increase in the wind power penetration rate. Moreover, SOPs are more applicable to the safe operation of the IEGDS under high energy load conditions.

Investigation of methane gas bubble dynamics and hydrate film growth during hydrate formation using 4-D time-lapse synchrotron X-ray computed tomography

Investigation of methane gas bubble dynamics and hydrate film growth during hydrate formation using 4-D time-lapse synchrotron X-ray computed tomography

CO2-Emissions as a Measure of Energy Efficiency in the Production and Application of Fertilizers

Taking into account the huge amount of data accumulated in recent years on greenhouse gas emissions (primarily CO2, methane, or greenhouse gases (GHGs)), it is possible to consider the problem of energy efficiency (carbon dioxide emissions occur primarily during fuel combustion, as well as methane and CO2 as precursors for nitrogen fertilizers) in the chain from the production of fertilizers to their logistics, application, production and waste disposal. At the same time, GHGs emissions can be considered as a measure of energy efficiency in assessing the life cycle of mineral fertilizers. Relevant examples are provided in the review.

Evaluating the impact of sodium chloride and iron carbonate ions on gas hydrate formation in Monoethylene Glycol‐enhanced aqueous solutions

AbstractThe management and prevention of hydrates are crucial for the gas industry. This study delves into the intricate challenges associated with gas hydrate formation, with a specific focus on investigating the impact of corrosion by‐products on prevention strategies. Employing a distinctive methodology, the sapphire pressure–volume temperature (PVT) cell was utilized. Experimental tests were conducted using sodium chloride (NaCl) concentrations of 1% and 3% to simulate brine solution levels at the wellhead, incorporating 3% filtrate and unfiltered iron carbonate (FeCO3) as corrosion products associated with the production process. The 1% and 3% salt concentrations were chosen to encompass a broad range of temperature depressions, reflecting common industry standards for simulating realistic environmental conditions. PVT cell test conditions ranged from 80 to 200 bar, with increments of 40 bar. The experiments investigate the effects of common pipeline salts on a monoethylene glycol (MEG)/water mixture in the presence of methane gas at typical industry high‐pressure conditions. The investigation uncovers that the introduction of salts to water, methane, and MEG solutions serves as a hydrate inhibitor, with inhibitory effects directly correlated to salt concentration. While generally hydrate growth inhibition is beneficial in natural gas pipelines, the findings indicate that elevated salt concentrations and lower pressure conditions contribute to the formation of larger hydrates, heightening the risk of surface adhesion and potentially introducing complications in piping equipment, despite the decreased temperature at which these hydrates form due to the inhibitory effects of the salts. In particular, the mixed condition of 3% NaCl and 3% FeCO3 (filtered) has the strongest effect. Examination of hydrate formation temperature and macroscopic observations suggests that the existence of substantial precipitates, as evidenced in the unfiltered FeCO3 sapphire cell experiment, may have the potential to enhance hydrate growth.

A Comprehensive Integration and Synthesis of Methane Emissions from Canada's Oil and Gas Value Chain.

Methane emissions from the global oil and gas value chain are a major contributor to climate change, and their mitigation could avoid 0.1 °C of warming by 2050. Here, we synthesize nearly a decade of research encompassing thousands of multiscale methane measurements along the oil and gas value chain (production to end use) to better constrain estimates of methane emissions from Canada's energy sector and to identify research gaps contributing to uncertainty in current estimates. We find that total value chain methane emissions are 2,600 (2,100-3,700) kt, which broadly agrees with Canada's latest official inventory that now includes atmospheric measurement data in some of their oil and gas methane estimates. Accurate understanding of emission magnitudes is critical because Canada committed to a 75% reduction of oil and gas methane emissions by 2030. We also identify and discuss information gaps in both emissions and activity data, namely, from the midstream, downstream, and end-use sectors. While they make up a smaller portion of the total inventory, accurate quantification of these emissions is still important and could point to more cost-effective mitigation solutions. This work emphasizes the need for frequent, comprehensive measurements to better constrain the climate impacts of the oil and gas sector and to validate reductions and commitments pledged by industry and governments.

Investigation into the variation characteristics and influencing factors of coalbed methane gas content in deep coal seams

Gas saturation is a critical parameter for the selection and development of coalbed methane, as well as a key indicator reflecting the challenges in coalbed methane development and productivity evaluation of coalbed methane wells. As one of the significant factors influencing gas saturation, gas content plays a vital role in comprehensively investigating coal pore properties to fully comprehend the process and conditions of methane adsorption and desorption. In this study, 3# and 15# coals from Qinshui Basin, China was selected as research subjects. The experimental evaluation encompassed an examination of composition, pore characteristics, permeability characteristics of coal, rock mechanical parameters while discussing the impact of temperature and pressure on coal's adsorption and desorption capacity. The mineral characteristics analysis revealed that vitrinite is the main component with varying percentages and reflectance values in both 3# and 15# coal seams. The gas content and methane concentration in the 15# coal seam are higher than those in the 3# coal seam. The relationship between gas content within a coal seam and burial depth depends on achieving a balance between positive pressure effects caused by overburden stress exertion on gases trapped within pores under high pressures during burial history versus negative temperature effects due to cooling during geological processes over time. Predictions were made regarding deep-coal gas content which holds significant implications for accurately understanding variations in desorption behavior along with optimizing fracturing engineering.

Climate Change Causes Food Insecurity for Developing Countries

At the moment, climate change is one of the most urgent issue worldwide. This is due to long-term climate trends and changes in social lifestyle. Another reason is the greenhouse gases produced by excessive fuel use. The intensity of weather, the decline in human health, and the devastation of natural ecosystems are all contributing factors. Intergovernmental Panel on Climate Change (IPCC) suggests controlling the avaeage temperate rise at 1.5 degrees Celsius to reduce global warming's intensity. The three major green house gasses responsible for global warming are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emitted from burning fossil fuels. Climate change is affecting the entire world, but poor and developing countries are suffering the most. The effects of climate change are all-encompassing. It affects agriculture, human health and crop productivity. A decrease have been observed in maize and wheat production in worst cases of climate change. This deficiency can lead to a food crisis. Poor and developing countries do not have the necessary resources to cope with the situation. They can't mould themselves quickly enough. Due to the lack of resources, they cannot discover new seeds to increase food production and are unable to improve their irrigation system. Climate change and rising temperatures contribute to the rapid growth of harmful bacteria and pathogens. These microbes have become a source of food contamination. Changes in rainfall patterns is also an important issue that affects the agricultural sector and the quality of irrigation water used. The risk of water pollution also increases. The gases produced from food waste, like greenhouse gases, are also harmful. Food waste in neighbourhoods releases methane gas, harming the environment. Commodity shortage and rising prices are major problems for people in poor and developing countries. The best strategy to deal with all these problems is to find new methods for agriculture that cope with climate change. To solve all these problems, government and international organizations should come forward and work together to help poor nations.

A promoter-RBS library for fine-tuning gene expression in Methanosarcina acetivorans.

Methanogenic archaea are potent producers of the greenhouse gas methane and thus contribute substantially to global warming. Under controlled conditions, these microbes can catalyze the production of biogas, which is a renewable fuel, and might help counter global warming and its effects. Engineering the primary metabolism of Methanosarcina acetivorans to render it better and more useful requires controllable gene expression, yet only a few well-characterized promoters and RBSs are presently available. Our study rectifies this situation by providing a library of 33 different promoter-RBS combinations with a 140-fold dynamic range in expression strength. Future metabolic engineering projects can take advantage of this library by using these promoter-RBS combinations as an efficient and tunable gene expression system for M. acetivorans. Furthermore, the methodologies we developed in this study could also be utilized to construct promoter libraries for other types of methanogens.

Enhanced Fischer-Tropsch synthesis through structured bed configurations and zeolite integration

The highly exothermic nature and wide range of products of the Fischer-Tropsch (FT) synthesis motivated the study of the influence of different fixed bed configurations on the conversion stability and selectivity of the system. A cobalt catalyst (Co-Ru/Al2O3) was synthesized as a fixed-bed powder reference and compared with monoliths (230 and 770 cpsi) loaded by the washcoating method. The monolith with the lowest cell density showed the greatest stability among the systems evaluated, with no drop in CO conversion during the 50-hour test. The same powder bed was compared with dual-bed configurations and physical mixing with HZSM-5 zeolite. These experiments showed that by adding HZSM-5 zeolite bed after the FT catalyst one can effectively increase the gasoline range selectivity, without favoring the formation of methane and C2-C4 gases. However, when the same mass of zeolite was physically mixed in a single bed, the formation of the C1-C4 fraction increased from 23 % to 33 %. The strategies employed improved product distribution and reduced the deactivation rate compared to the conventional single bed.

The Additive to Mass Manufacturing Process of Mixed Potential Electrochemical Sensors

Additive manufacturing allows for quick turn around and low cost of production of small numbers of parts. These attributes lend the technology to prototype development, where design changes are many and production numbers are low [1]. Once design parameters have been nailed down, additive manufacturing’s low throughput and poor reproducibility limit application to high volume production.Here, we discuss the implementation of direct-write extrusion of ceramic pastes and metal inks for prototype manufacturing of mixed potential electrochemical sensors and the transition to tape casting and screen printing for high volume production. Throughout the prototyping phase, direct write extrusion enabled quick and easy production of low numbers of parts, enabling various changes in sensor design and material to improve sensor performance. Sensor design evolved from a disk shape (Fig. 1 a) to a stick with integrated heater (Fig. 1 b, c). Direct write extrusion of substrate enabled quick testing of various stabilized zirconia ceramics to improve the sensitivity of the device [2]. Limitations of additive manufacturing became apparent when attempting to integrate the heater into the device, the inconsistent linewidths led to areas of high resistance and hot spots (Fig. 1 c). Tape-casting and screen printing of the devices was adopted for three reasons, first, to improve line fidelity, which is vitally important when printing small electrodes as well as heater traces (Fig. 1 d), second, to further decrease conductivity of substrate by laminating multiple layers of different ceramic materials, and finally to increase manufacturing throughput (Fig. 1 d, e).This work was supported by US Department of Energy Award DE-FE0031864References[1] T. D. Ngo, A. Kashani, G. Imbalzano, K. T. Q. Nguyen, and D. Hui, “Additive manufacturing (3D printing): A review of materials, methods, applications and challenges,” Compos. Part B Eng., vol. 143, pp. 172–196, Jun. 2018, doi: 10.1016/j.compositesb.2018.02.012.[2] S. Halley, K. Ramaiyan, F. Garzon, and L. Tsui, “Massive enhancement in sensitivity of mixed potential sensors towards methane and natural gas through magnesia stabilized zirconia low ionic conductivity substrate,” Sens. Actuators B Chem., vol. 392, p. 134031, Oct. 2023, doi: 10.1016/j.snb.2023.134031. Figure 1