High Carbon Dioxide Emissions Research Articles

Recent Progress on Porous Carbons for Carbon Capture.

High emission of carbon dioxide (CO2) has caused CO2 levels to reach more than 400 ppm in air and led to a serious climate problem. In addition, in confined spaces such as submarines and aircraft, the CO2 concentration increase in the air caused by human respiration also affects human health. In order to protect the environment and human health, the search for high-performance adsorbents for carbon capture from high and low concentration gas is particularly important. Porous carbon materials, possessing the advantages of low cost and renewability, have set off a boom in the research of porous adsorbents, which have the opportunity to be utilized on a large scale for industrial carbon capture in the future. In this review, we summarize the recent research progress of porous carbons for carbon capture from flue gas and directly from air in the last five years, including activated carbon (AC), heteroatom-modified porous carbon, carbon molecular sieves (CMS), and other porous carbon materials, with a focus on the effects of temperature, water content, and gas flow rate of industrial flue gas on the performance of porous carbon adsorbents. We summarize the preparation strategies of various porous carbons and seek environmental friendly porous carbon materials preparation strategies under the premise of improving the CO2 adsorption capacity and selectivity of porous carbon adsorbents. Based on the effects of real industrial flue gas on adsorbents, we provide new ideas and evaluation methods for the development and preparation of porous carbon materials.

Greenhouse gas emissions, carbon stocks and wheat productivity following biochar, compost and vermicompost amendments: comparison of non-saline and salt-affected soils

Understanding the impact of greenhouse gas (GHG) emissions and carbon stock is crucial for effective climate change assessment and agroecosystem management. However, little is known about the effects of organic amendments on GHG emissions and dynamic changes in carbon stocks in salt-affected soils. We conducted a pot experiment with four treatments including control (only fertilizers addition), biochar, vermicompost, and compost on non-saline and salt-affected soils, with the application on a carbon equivalent basis under wheat crop production. Our results revealed that the addition of vermicompost significantly increased soil organic carbon content by 18% in non-saline soil and 52% in salt-affected soil compared to the control leading to improvements in crop productivity i.e., plant dry biomass production by 57% in non-saline soil with vermicompost, while 56% with the same treatment in salt-affected soil. The grain yield was also noted 44 and 50% more with vermicompost treatment in non-saline and salt-affected soil, respectively. Chlorophyll contents were observed maximum with vermicompost in non-saline (24%), and salt-affected soils (22%) with same treatments. Photosynthetic rate (47% and 53%), stomatal conductance (60% and 12%), and relative water contents (38% and 27%) were also noted maximum with the same treatment in non-saline and salt-affected soils, respectively. However, the highest carbon dioxide emissions were observed in vermicompost- and compost-treated soils, leading to an increase in emissions of 46% in non-saline soil and 74% in salt-affected soil compared to the control. The compost treatment resulted in the highest nitrous oxide emissions, with an increase of 57% in non-saline soil and 62% in salt-affected soil compared to the control. In saline and non-saline soils treated with vermicompost, the global warming potential was recorded as 267% and 81% more than the control, respectively. All treatments, except biochar in non-saline soil, showed increased net GHG emissions due to organic amendment application. However, biochar reduced net emissions by 12% in non-saline soil. The application of organic amendments increased soil organic carbon content and crop yield in both non-saline and salt-affected soils. In conclusion, biochar is most effective among all tested organic amendments at increasing soil organic carbon content in both non-saline and salt-affected soils, which could have potential benefits for soil health and crop production.

The Living Concrete Experiment: Cultivation of Photosynthetically Active Microalgal on Concrete Finish Blocks

Climate change is a global critical issue. High carbon dioxide emissions and concentrations are important factors. In the construction field, concrete contributes significantly to greenhouse gas emissions. Therefore, a pioneering team of researchers has developed a new “living concrete” construction finish material capable of scrubbing carbon dioxide from the atmosphere. The material consists of ASTM (ASTM is the acronym for American Society for Testing Materials)-certified concrete block(s) with Chlorella vulgaris cultivated on the surface. Chlorella vulgaris is a common micro-algae with photosynthetic activity; these species require water, nutrients, light, and carbon dioxide to live while releasing oxygen in return. The “living concrete” block was developed in dedicated laboratories; its photosynthetic activity was quantified. Proposed as an external application assembly to a new or an existing building envelope—up to 3 m high, i.e., anthropogenic street-level emissions, or installed on roof(s) in horizontal mode—this concrete/biological composite material reverses carbon dioxide emissions and may present itself as a valid solution for climate change issues in urban moderate climates.

Development of a Low-Density Waste-Based Geopolymer Construction Material

The construction industry, integral to national infrastructure development, faces environmental challenges attributed to Portland cement’s high energy consumption and carbon dioxide emissions during production. To address this challenge, this study integrated waste fly ash and polystyrene into geopolymers to enhance environmental sustainability and economic feasibility. The objectives included developing low-density geopolymers using polystyrene inclusion, optimizing component mixing ratios, assessing activator concentration effects, determining the optimal curing conditions, and characterizing the resulting geopolymers. Through experimental investigation, low-density geopolymers were developed with optimized component ratios and curing conditions. The experimental procedure began with the classification of fly ash to determine its suitability for various applications, revealing it to be type F. Geopolymers were fabricated using a mixture of fly ash, water, sodium hydroxide activator, and polystyrene. Varied concentrations of sodium hydroxide and polystyrene were employed. Two curing temperatures, 60 °C and 100 °C, were explored. The results showed that greater sodium hydroxide concentrations improved the structure and compressive strength of the geopolymers. The results also demonstrated a significant correlation between the curing conditions and the mechanical properties of the produced geopolymers. The goal of reducing the density of the geopolymers for lightweight thermal-resistant applications was achieved through polystyrene incorporation. However, polystyrene incorporation negatively impacted the compressive strength. The optimum production conditions for the sodium hydroxide-varied samples were 8 g sodium hydroxide/g sample cured at 100 °C, while the optimum production conditions for polystyrene-varied samples were 1 g polystyrene/g sample cured at 60 °C. The findings confirmed the viability of utilizing fly ash and polystyrene wastes to produce sustainable, low-density, thermal-resistant construction materials. Overall, increasing activator concentration enhances the strength and durability of geopolymers, while polystyrene contributes to the development of lightweight geopolymers, provided the appropriate amount is utilized. To ensure replicability, the formulation procedure and input quantities must be tailored according to the intended geopolymer application. These insights offer practical guidance for optimizing geopolymer manufacturing processes towards enhanced sustainability and performance.

The impact of the EU's Carbon Border Adjustment Mechanism on the global iron and steel trade and emission reduction.

The European Council completed the legislative procedure to establish the Carbon Border Adjustment Mechanism (CBAM) on April 25, 2023, which will be launched in 2027. The iron and steel sector is the main target of the forthcoming CBAM due to the industry's energy-intensive consumption with high carbon dioxide (CO2) emissions. However, minimal existing research has been conducted in this regard. This study employs GTAP-e 11.0 and TOPSIS models to estimate the effects of CBAM implementation on the major nations around the world from 2027 to 2030, examining countries' GDP, social welfare, iron and steel production, trade balance, and CO2 emissions to the global environment. This study concludes: (1) The GDP and social welfare of important iron and steel trade partners throughout the world will be significantly impacted by the application of CBAM. Most nations, including those in the EU, will experience negative GDP effects, with China undergoing the most pronounced social welfare declines followed by India. In contrast, the EU27 will benefit the most in terms of social welfare, followed by the US, Japan, and Russia. (2) Iron and steel production will decrease in all countries outside the EU, but it will have a positive impact on the trade balance of most countries. (3) The CO2 emissions of all countries except for the EU and Japan will decrease, with a positive impact on preventing carbon leakage in the international iron and steel trade. (4) Comprehensive analysis demonstrates that the EU will benefit the most, and China will suffer the most from CBAM application. Based on the above conclusions, this study proposes corresponding policy recommendations.

Analysis of compressive strength, durability properties, and micromechanisms of solidified loess using industrial solid waste: Slag–white mud–calcium carbide residue

Traditional lime-solidified loess presents the issue of high carbon dioxide emissions. This paper presents the development of a kind of cementitious material using industrial solid waste: slag–white mud–CCR (calcium carbide residue). The slag mainly contains CaO, SiO2, and Al2O3, with a 10.6 pH value. The white mud and CCR mainly contain CaCO3 and Ca(OH)2, respectively. We further assessed the efficacy of slag–white mud–CCR in solidified loess and employed SEM and TG/DTG to explore their micromechanisms. The pH value of the CB4 sample (slag–white mud–CCR with the lowest CCR content) was 42.3 % higher than that of pure loess. Considering the 3-day and 28-day compressive strength and the material costs, the optimal mortar mixture ratio was found to be slag–white mud–CCR = 60:32:8, and this mixture was used to solidify loess. The unconfined compressive strength of 15 % slag–white mud–CCR-solidified loess is almost 5.0 times and 6.0 times higher than that of lime-solidified loess at 7 and 28 days of curing age, respectively. The durability of the solidified loess after freeze–thaw and wet–dry cycles was significantly improved compared with that of lime- or slag-solidified loess. Specifically, 10 % and 15 % slag–white mud–CCR-solidified loess maintained a high compressive strength after eight freeze–thaw and wet–dry cycles. SEM and TG/DTG analyses of the mortar and solidified loess confirmed the formation of hydration products of C–S–H- and C-A-(S)–H-type gels. The compressive strength results were obtained using a dual mechanism: the cementation of loess particles through the formation of hydration products and their subsequent filling action.

Low-carbon economic analysis of a virtual power plant with wind and solar power considering the integrated flexible operation mode of a carbon capture thermoelectric unit

During the period when heating is required in North China, the task of meeting the heating needs of customers is mainly undertaken by thermoelectric units under the ”determining electricity by heat” operation mode. This heating mode leads to difficulties in incorporating renewable energy and high carbon dioxide emissions. To solve these problems, carbon capture technology and wind power heating technology are introduced in this study. Cogeneration units with a carbon capture integrated flexible operation mode are introduced into the system to reduce CO2 emissions, while making the electric output and the thermal output more flexible. Then, the cogeneration optimal scheduling model of a virtual power plant is constructed. This model includes wind power heating equipment and carbon capture cogeneration units under the integrated flexible operation mode. Due to the highly nonlinear characteristics of the model, we solve this problem by the Deep Q-Network (DQN) algorithm, which is an algorithm that uses the nonlinear approximation value function of a neural network to make the model more robust. Finally, we propose three technical strategies and compare the results of the three strategies in terms of low carbon levels and economic value. The results show that the model can effectively improve the economic income of the system and reduce carbon emissions.

Carbon dioxide and nitrate co-electroreduction to urea on CuOxZnOy

Urea is a commonly used nitrogen fertiliser synthesised from ammonia and carbon dioxide using thermal catalysis. This process results in high carbon dioxide emissions associated with the required amounts of ammonia. Electrocatalysis provides an alternative method to urea production with reduced carbon emissions while utilising waste products like nitrate. This manuscript reports on urea synthesis from the electroreduction of nitrate and carbon dioxide using CuOxZnOy electrodes under mild conditions. Catalysts with different ratios of CuO and ZnO, synthesised via flame spray pyrolysis, were explored for the reaction. The results revealed that all the CuOxZnOy electrocatalyst compositions produce urea, but the efficiency strongly depends on the metal ratio composition of the catalysts. The CuO50ZnO50 composition had the best performance in terms of selectivity (41% at −0.8 V vs RHE) and activity (0.27 mA/cm2 at −0.8 V vs RHE) towards urea production. Thus, this material is one of the most efficient electrocatalysts for urea production reported so far. This study systematically evaluates bimetallic catalysts with varying compositions for urea synthesis from carbon dioxide and nitrate.

Development of bio-based blended ash and fly ash-based alkali-activated concrete

Owing to rapid industrialisation and urbanisation there has been a significant increase in the manufacture and application of cement, resulting in high carbon dioxide (CO2) emissions into the atmosphere. This paper investigates alternative binders that have reduced carbon dixoide emissions and better performance. The study elaborates the mix design of novel concrete, wherein the principle raw material used was locally available bio-based blended ash (BA) procured from the co-combustion process with sodium-based alkali activators. The physical, chemical, mineral and morphological characteristics of BA were studied. Beside this, the influence of parameters such as molarity of sodium hydroxide (NaOH), liquid sodium silicate (LSS) to NaOH ratio, fly ash (FA) to BA ratio and method of curing on the physico-mechanical properties of alkali-activated concrete as a sustainable construction material were studied. Higher characteristic strength was attained with an increase in these parameters. A maximum characteristic strength of 42.31 MPa at day 28 was obtained with 8 M NaOH, LSS/NaOH ratio of 1.5 and FA/BA ratio of 3. The average flexural and split tensile strength obtained were 3.70 and 2.72 MPa, respectively. The experimental investigation of the alkali-activated concrete using BA and FA proved to be an efficient solution for zero-cement concrete with improved performance.

Facile Synthesis of Supported Ir-Based OER Electrocatalysts Via Sputtering

Hydrogen has been regarded as a promising energy carrier for renewable energy systems with net zero emissions [1]. However, the vast majority of industrial hydrogen has been produced from fossil fuels with high carbon dioxide (CO2) emissions [2]. An emerging method for hydrogen production potentially free of greenhouse gas emissions (so-called green hydrogen) is water electrolysis coupled to renewable energy sources such as wind, solar, hydropower, etc [3]. Among several water electrolysis technologies, proton exchange membrane water electrolyzers (PEMWEs) are the most promising due to several inherent advantages [4]. However, the large amount of iridium (Ir) used in current PEMWEs versus the limited amount of Ir resource on earth impedes large-scale and sustainable deployment of PEMWEs [5]. Lowering the amount of Ir used to efficiently catalyze the oxygen evolution reaction (OER) at PEMWE anodes might be achieved through the development of novel electrocatalysts.One strategy to reduce the Ir content of PEMWE anodes is to put Ir onto a support. This strategy can not only reduce the Ir content by improving Ir utilization in comparison with unsupported Ir-based electrocatalysts, but also decrease the Ir packing density [6]. Low Ir packing density is required for electrocatalyst layers with low Ir-contents to be sufficiently thick to ensure robust interfaces between the electrocatalyst layer and the porous transport layer (PTL) and membrane [7]. This strategy has two critical steps: (1) finding/developing a robust support and (2) depositing Ir onto the support with desired morphology with a method that is affordable, scalable, and manufacturable [8].Here we report a one-step deposition of Ir onto nanoscale tungsten-doped titanium dioxide (W-TiO2) powders via sputtering. Characterization shows that Ir is deposited onto the surface of W-TiO2 (Figure 1) in the mixed form of metallic Ir and Ir oxides with particle sizes smaller than 2 nm. The catalyst exhibits an OER mass activity twice that of Ir black in acidic media. Powder conductivity measurements confirm that the electrocatalyst is electrically conductive (~24 S/cm) despite the low conductivity of the W-TiO2 powders (~1×10-4 S/cm). Our study suggests that sputtering is a feasible deposition method for large-scale production of supported Ir-based OER electrocatalysts. Acknowledgement. This study is sponsored by internal funding from Plug Power. The sputter was done at Exothermics Inc., 14 Columbia Dr, Amherst, NH 03031 References [1] Hydrogen for Net-Zero. In A critical cost-competitive energy vector. Edited by. Hydrogen Council, McKinsey & Company; 2021.[2] IEA (2021), Global Hydrogen Review 2021, IEA, Paris (available via the Internet at: https://www.iea.org/reports/global-hydrogen-review-2021)[3] Emonts, B., Müller, M., Hehemann, M., Janßen, H., Keller, R., Stähler, M., ... & Kasselmann, S. (2022). A Holistic Consideration of Megawatt Electrolysis as a Key Component of Sector Coupling. Energies, 15(10), 3656.[4] Zhang, K., Liang, X., Wang, L., Sun, K., Wang, Y., Xie, Z., ... & Zou, X. (2022). Status and perspectives of key materials for PEM electrolyzer. Nano Research Energy, 1(3), e9120032.[5] Mittelsteadt, C. (Invited) Ir Strangelove: Or How I Learned to Stop Worrying and Embrace the PEM. ECS Meeting s MA2022-01, 1335-1335 (2022).[6] Bernt, M., Hartig‐Weiß, A., Tovini, M. F., El‐Sayed, H. A., Schramm, C., Schröter, J., ... & Gasteiger, H. A. (2020). Current challenges in catalyst development for PEM water electrolyzers. Chemie Ingenieur Technik, 92(1-2), 31-39.[7] Bernt, M., Siebel, A., & Gasteiger, H. A. (2018). Analysis of voltage losses in PEM water electrolyzers with low platinum group metal loadings. Journal of The Electrochemical Society, 165(5), F305.[8] Jia, Q., Ghoshal, S., Li, J., Liang, W., Meng, G., Che, H., ... & Mukerjee, S. (2017). Metal and metal oxide interactions and their catalytic consequences for oxygen reduction reaction. Journal of the American Chemical Society, 139(23), 7893-7903. Figure 1

Comparative Life Cycle Assessment and Exergy Analysis of Coal‐ and Natural Gas‐Based Ammonia Production

AbstractA comprehensive life cycle assessment (LCA) analysis of ammonia production is presented, focusing on the comparison between natural gas‐based and coal‐based processes. Ammonia production is associated with high energy consumption and significant carbon dioxide (CO2) emissions. The objective of this research is to identify key processes and parameters within the ammonia synthesis industry and provide recommendations for cleaner and more sustainable development. Exergy analysis is performed to assess the efficiency of ammonia production technologies and determine optimal operating conditions. Natural gas‐based ammonia production has lower environmental impacts compared to coal‐based production in most categories, except for ionizing radiation. Natural gas, being a cleaner‐burning fossil fuel, produces fewer greenhouse gas emissions and other air pollutants. However, it is essential to address the issue of ionizing radiation in natural gas‐based processes. The potential for more efficient technologies and the importance of removing sulfur and other impurities during the production process to optimize catalyst performance are highlighted.

Green development of fly ash geopolymer via casting and pressing Approaches: Strength, Morphology, efflorescence and Ecological Properties

The high liquid content of cast geopolymer not only limits its strength development and durability but also leads to high energy consumption and carbon dioxide (CO2) emissions. Thus, a study of the cast and pressed geopolymer was performed. The geopolymers were cured for 1, 7 and 28 d before testing and characterizations. With the incorporation of pressure compaction, higher bulk density (2158–2227 kg/m3) was recorded for pressed geopolymer in comparison to cast geopolymer (1842–1854 kg/m3). The dense matrix in pressed geopolymer improved the inter-particle contact, increasing the 28 d degree of reaction to 39.7%, higher than that of cast geopolymer (33.0%). This feature was proved by SEM micrographs wherein the pressed geopolymer was well-compacted and denser in microstructure, with less unreacted/partially reacted fly ash and pores. The compressive and flexural strengths of pressed geopolymer reached 114.2 and 29.9 MPa after 28 d, higher than that of cast geopolymer (60.0 and 6.2 MPa, respectively). The strength reduction of pressed geopolymer (31.7%) after the accelerated efflorescence test was lower than that of cast geopolymer (60.2%). The ecological analysis inferred that pressed geopolymer was ecologically superior to the casting method in terms of embodied energy (EE) and embodied carbon dioxide emission (ECO2), in which 50% and 59% of reductions are acquired. Besides, the embodied carbon index (ECI) of pressed geopolymer was about 21% of cast geopolymer.

From Fossil Fuels to Renewables: Analyzing the Pathways to Carbon Emission Reduction in Developing Nations

The present study endeavours to examine the determinants that contribute to the enhancement of environmental quality within specific developing economies while concurrently assessing the validity of transitioning these economies from fossil fuel dependency to renewable energy sources. To achieve this objective, panel data encompassing selected developing economies spanning the period from 2000 to 2022 has been collected from the World Development Indicators database. Fossil fuel consumption is quantified through measures of energy consumption, while renewables are gauged using indicators of renewable energy consumption and renewable electricity consumption. In terms of analytical methodology, both fixed-effect and random-effect models have been employed. The estimated coefficients from the empirical analysis reveal that energy derived from fossil fuels significantly correlates with higher carbon dioxide emissions in the selected developing countries, suggesting that a shift toward renewable energy sources and electricity consumption can serve as an effective strategy for mitigating carbon emissions. Furthermore, the findings indicate that carbon dioxide emissions may be curbed through the facilitation of international trade and the expansion of industrial activities. Conversely, greater levels of foreign direct investment (FDI) and government expenditure appear to be associated with increased carbon dioxide emissions in these developing economies. In light of these findings, it is recommended that the promotion and adoption of renewable energy sources such as solar, wind, hydropower, and geothermal energy be prioritized as a means of effectively reducing carbon emissions and fostering environmental sustainability within these developing nations.

The Impact of COVID-19 Outbreak on CO2 Emissions in the Ten Countries with the Highest Carbon Dioxide Emissions.

The environmental pollution during the COVID-19 crisis has declined dramatically due to quarantines that have severely reduced transport and industry but has had little effect on the steady rise in CO2 concentrations in the atmosphere. Through the Paris Agreement, countries are working to reduce the emissions of these pollutants, for example, by burning fossil fuels. These greenhouse gases trap heat near the earth's surface and raise the temperature. This global warming threatens global food resources. In times of corona crisis and environmental pollution, especially in countries with the highest CO2 emissions, governance is a key factor that explains the poor economic, social, and environmental performance of many countries. Governance plays an important role in controlling these crises. In this study, the World Bank's governance indicators have been used to examine the relationship between governance and economic performance and its impact on CO2 emissions during the COVID-19 outbreak period. Also, the Tobit panel model with a limited-dependent model from 2011 to 2020 has been used. Several economic factors and governance variables are also considered. Given the negative relationship between governance and CO2 emissions during the COVID-19 outbreak, the role of governance in reducing environmental pollution is emphasized, and it is shown that policymakers can take appropriate measures by implementing good governance and enforcing the right laws to control the corona epidemic and also reduce carbon emissions in the long run.

Blue ammonia an attractive pathway to decarbonize conventional ammonia plants

Ammonia is one of the basic ingredients for the fertilizer and mining explosive industries. Conventional ammonia production technologies have a high environmental impact owing to its high carbon dioxide (CO2) emissions. This study evaluates the prospects of blue ammonia through integration of different available technologies within conventional ammonia plants: the Kellogg Braun & Root (KBR) Purifier process, Topsoe and the Linde Ammonia process. Carbon Capture and Sequestration (CCS) and Gas Switching Reforming (GSR) technology are attractive pathways toward blue ammonia due to cost effectiveness and ease of implementation. Blue ammonia technology development has its own challenges to overcome while it has massive advantages and opportunities like blue ammonia utilization as an alternative fuel, availability of pre-existing infrastructure available for storage, enhanced oil production through CO2 pressurization. Given the increasing demand and international ammonia trade, advanced blue ammonia production from different available technologies like CCS & GSR offers an alluring way for natural gas exporting regions to contribute to global decarbonization.

A Literature Review of Low-Carbon Urban Tourism Indicators and Policy

Low-carbon tourism (LCT) should be promoted in the development of the tourism sector, particularly in urban tourism, associated with the issue of high carbon dioxide emissions from human transportation-related activities and environmental pollution. Unfortunately, until today, there are still no specific guidelines for developing LCT in urban areas on the implementation or assessment criteria for determining the low carbon level. In consequence, the goal of this article is to discuss low-carbon indicators and policies used in the development of urban tourism. We identified 159 low-carbon indicators through content analysis, after reviewing reliable resources from four journal articles and a government policy paper validated using qualitative methods. Some suggested strategies and policies for LCT activities, actions and cooperation from the authorities and residents in implementing LCT as a new tourism development model. The results can be used globally as a basis for the formation of policies and studies related to LCT in urban areas.

Proposal of an environmental-friendly poly-generation model regarding the flue gas processing for the production of electricity, cooling, heating, freshwater, and methanol

In this paper, a novel poly-generation system with high thermodynamic performance and low carbon dioxide (CO2) emission is presented and analyzed from the 4E (energy, exergy, economic, and environmental) perspective. The newly designed structure consists a gas turbine cycle, transcritical CO2 cycles, a Kalina power cycle, a water desalination unit, a methanol production unit, and a chiller. Toward this goal, the flue gas leaving the gas turbine cycle is processed and utilized. Thermodynamic analysis demonstrates that the total energy and exergy efficiencies are attainable at 58.75% and 69.46%, respectively. In addition, the total exergy destruction rate equals 183105 kW in which the gas turbine cycle is the major source of irreversibility with a share of 51%. In addition, exergy analysis indicates that the combustor of the gas turbine cycle has the highest exergy destruction ratio (44.54%) among all equipment. Regarding the environmental aspect, the total CO2 emission and its emission intensity for the proposed process are 18678.42 kgCO2/h and 0.75 kgCO2/kgMeOH, respectively. Its indirect emission is responsible for 48.8% of the total emission as well. Attributable to the thermo-environmental results, the proposed process has a suitable performance compared to similar technologies. The economic analysis demonstrated that its total annual cost equals 60800563 $ and production costs of methanol, freshwater, heating, cooling, and power are 0.3 $/kgMeOH, 0.43 $/kgfreshwater, 0.16 $/kgLPS, 0.022 $/kgchilled water, and 0.069 $/kWh, respectively.

Analyzing the impact of demand response and reserves in islands energy planning

Small Islands usually rely on fossil fuels for their energy supply and face common challenges such as high energy costs and carbon dioxide emissions. For these reasons they represent interesting cases for analysing the transition towards a clean and secure energy system. Nevertheless, integrating non-dispatchable Renewable Energy Sources in the power grid causes stability issues and this is particularly true for island grids. Such issue is not fully considered in long-term energy planning; indeed, an important factor that should be considered in order to ensure the reliability of the grid are Reserves. There are different types of Reserves depending on the reactiveness/response time and the duration of the service. In this paper, primary and secondary reserves have been analysed in order to plan the long-term energy transition of the small island of Favignana, Italy by means of the new version of H2RES, a Linear Programming single-objective optimisation model able to provide a long-term capacity investment and dispatching optimisation. It has been found that biomass generators are favoured to both photovoltaic and wind turbines for their ability to provide reserves and also decrease the unpredictability of the supply. Batteries and Electrolysers are also used mostly for reserve provision.

Novel coal char-based cement grout: An experimental study on geotechnical and rheological properties

Coal char, a light and porous coal byproduct, is conventionally used for combustion and gasification, which leads to high carbon dioxide and other air pollutants emissions. In this study, the feasibility of using coal char in cement grout is evaluated. The coal char pyrolyzed at 850 °C is produced from Powder River Basin coal in Wyoming. Effects of char contents (up to 50%) and particle sizes (<300 μm and 300–850 μm) on geotechnical and rheological properties of char-cement grouts are comprehensively investigated. Compared to cement grout, the compressive strength of char-cement grout is 16% higher, and the final setting time is 55% shorter. The addition of coal char effectively reduces the bleeding in grouts without leading to a significant increase in Marsh viscosity. In general, coal char can provide many advantages towards improving engineering performance and broadening application of conventional cement grout.

Insights into CO2 emissions in Europe in the context of COVID-19: A panel data analysis

This paper analyzes the dynamics of CO2 emissions over the last decade for a large group of 25 European countries, an issue that is at the center of the ecological transition project involving various commitments (COP21, COP26, G20 meetings, etc.). To this end, our model measures the repercussions of energy price shocks (oil, gas, coal) for carbon emissions, as well as changes in industrial production and sustainable development in the context of the coronavirus pandemic. Using annual data for 23 EU countries, together with Russia and the UK, our findings show that CO2 emissions reacted significantly to oil and coal price shocks and vary with industrial production cycles. We quantified this reaction while computing the related elasticities. Further, while a significant reduction in CO2 emissions was observed during the COVID-19 pandemic, the stepping up of investment in sustainable development and renewable energy consumption also had a negative impact on CO2 emissions. This suggests that the key driver to reducing the risk of climate change and lowering high carbon dioxide (CO2) emissions involves significant commitment to sustainable development.