Method For Reducing Emissions Research Articles

Efektifitas arang aktif tongkol jagung dalam menurunkan emisi kendaraan bermotor berbahan bakar ganda

Emission reduction through after treatment processes has become one of the options to minimize the adverse effects of two-wheeler emissions. Activated charcoal adsorbents have been proven effective in reducing emissions to a certain extent. In this study, corn cob charcoal activated with a 15% NaCl solution serves as the adsorbent. The adsorbent used is shaped into particles with a mesh size of 10. The adsorbent is placed in the modified motorcycle muffler. Testing is conducted on two-wheeled vehicles operated using the dual-fuel method, where biogas and pertalite are used as fuels. With this method, fuel concentrations are obtained significantly smaller compared to vehicles without emission reduction methods. Testing is carried out for 2 hours to determine the durability of the adsorbent in absorbing exhaust gas emissions. Based on the test results, where data collection is conducted every 10 minutes, the concentrations of emissions including hydrocarbons (HC), carbon monoxide (CO), and carbon dioxide (CO2) initially decrease and then rise again after several minutes. This indicates that the adsorbent effectively reduces emissions in a relatively short duration. However, the effectiveness of corn cob activated charcoal in reducing these three emissions varies, with the adsorbent showing good performance in reducing HC

Size fraction characterisation of highly-calcareous and siliceous fly ashes

AbstractThe properties of coal fly ash vary significantly depending on factors such as coal type, combustion conditions, and flue gas emission reduction methods. This study investigates the influence of particle size fractionation on the chemical composition, mineralogical structure, and thermal behaviour of two types of fly ash: high calcium ash derived from lignite (S1) and silica-rich ash from bituminous coal (S2). Dry aerodynamic separation was used to obtain distinct size fractions, which were then subjected to a comprehensive characterisation including X-ray fluorescence, X-ray diffraction, scanning electron microscopy, and thermal analysis. The results reveal notable differences between the S1 and S2 ashes and between their size fractions. The finer fractions (< 20 μm) of S1 showed an increased calcium and sulphur content, while the coarser fractions (> 100 μm) contained more silica and alumina. The S2 ash exhibited a higher overall silica content, with alkali metals concentrated in finer fractions. Thermal analysis demonstrated distinct behaviours for each type and fraction of ash. Fine fractions of S1 ash showed SO2 emission at elevated temperatures, while S2 ash exhibited greater CO2 gas emission. After thermal treatment, the recrystallisation of the glassy phase was observed for S1, while the S2 ashes were more prone to melting and agglomeration. The study highlights the potential for the customised utilisation of specific ash fractions in various applications, such as geopolymer synthesis, adsorbent materials, and refractory products. This comprehensive characterisation contributes to a better understanding of fly ash properties and their dependence on particle size, providing valuable insights to optimise fly ash utilisation in various industries. The findings suggest strategies for a more efficient use of fly ash resources, particularly relevant in the context of decreasing fly ash availability due to the phase-out of coal power plants.

Enhancement effect of semicoke waste heat on energy conservation and hydrogen production from biomass gasification

Key approaches to alleviating global warming and curbing fossil fuel depletion involve various industrial energy-conservation technologies and carbon dioxide (CO2) emission reduction methods. The production of hydrogen (H2)-rich gas from inexpensive and readily available biomass, as an alternative energy source, is becoming increasingly promising. However, this application faces challenges such as high energy consumption and low gas quality. In this study, the waste heat released by semicoke production from lignite gasification and CO2 from exhaust gas were utilized to gasify biomass. This approach aims to save energy in biomass gasification and use CO2 in exhaust gas to improve the H2 content in biogas. A simulation was conducted to recover semicoke waste heat by combining a suspension tube with CO2 flow to generate steam and high-temperature CO2, which were then simultaneously sent into a gasifier to produce H2 through biomass gasification. The results revealed that the rate of semicoke waste heat recovery exceeded 90 %. The yield of steam and the rate of waste heat recovery improved with increasing mass flow rate of semicoke and then slightly decreased with increasing steam pressure and CO2 mass flow rate. The yield of H2 increased with the semicoke mass flow rate and steam pressure. The rate of energy conservation ranged from 15 % to 239 %, peaking at a CO2 mass flow rate of 0.09 kg/s. Compared with the case without waste heat recovery, the economic benefits increased from 12 to 28 times.

DFT Study on Effect of Metal Type and Coordination Environment on CO2 ECR to C1 Products over M-N-C Catalysts.

Electrocatalytic reduction (ECR) of CO2 to chemical products is an important carbon emission reduction method. This work uses DFT to study the stability of N-doped graphene-supported four metal single-atom catalysts (M-N-C) and the effects of the coordination environment and metal centers on the selectivity of CO2 ECR to C1 products. The results show that Fe, Co, Ni, and Cu have good stability. The coordination environment has a significant modulating effect on product selectivity, and the change of the number of ligand nitrogen atoms will affect the size of the potential-limiting step of each product. When the number of nitrogen ligands is the same, the different metal centers of the M-N-C catalyst have a significant effect on the selectivity of different products. In addition, the introduction of nitrogen atom ligands can adjust the electronic structure of the graphene-supported metal center, increase the d-band center of most metals, and improve the reaction activity.

Research on enterprise production decision‐making considering consumer heterogeneity under carbon labeling system

AbstractThe article focuses on consumers with heterogeneous preferences for product carbon footprints under two carbon labeling systems: carbon reduction labels and carbon footprint labels. Using mathematical models, the study explores the optimal decision‐making behavior of enterprises under the carbon labeling system based on consumer utility theory at the enterprise level. It also investigates consumer surplus, environmental improvement, and social welfare under different production modes of the carbon reduction label and carbon footprint label systems at the societal level. The research findings are as follows: (1) At the level of economic benefits for enterprises, choosing to produce products with carbon reduction labels is more favorable when the investment costs for emission reduction are high, while choosing to produce products with carbon footprint labels is more favorable when the investment costs for emission reduction are low. The optimal prices of products under the two carbon labeling systems show opposite trends compared to the investment costs for emission reduction. (2) At the level of environmental benefits for enterprises, under the carbon reduction labeling system, whether through full production or a mixed production mode, enterprises are only willing to reduce the carbon footprint of products to the standard value. However, under the carbon footprint labeling system, especially in the mixed production mode, enterprises show a stronger willingness to overachieve in emission reduction target. (3) At the level of social benefits, compared to the situation under the carbon reduction labeling system, when the investment costs for emission reduction are low, the carbon footprint labeling system is more favorable in terms of consumer surplus and social welfare. However, this advantage gradually diminishes as the investment costs for emission reduction increase. (4) Excessive investment costs for emission reduction are detrimental to the implementation of both carbon reduction and carbon footprint labeling systems. The research conclusions suggest that companies should develop appropriate production strategies based on actual circumstances. Additionally, it is necessary for both the government and companies to reduce investment costs in emissions reductions by improving the system and optimizing emission reduction methods in order to better implement carbon labeling policies.

High Gravity-Enhanced Direct Air Capture: A Leap Forward in CO2 Adsorption Technology

Given the global pressure of climate change and ecological equilibrium, there is an urgent need to develop effective carbon dioxide (CO2) capture technology. Due to its comprehensiveness and flexibility, Direct Air Capture (DAC) technology has emerged as a vital supplement to traditional emission reduction methods. This study aims to innovate Direct Air Capture (DAC) technology by utilizing the ultrasonic impregnation method to load Tetraethylenepentamine (TEPA) onto alumina (Al2O3) as the adsorbent. Furthermore, high gravity adsorption technology is integrated to significantly enhance the efficiency of DAC. Characterization tests, including BET, FTIR, TG, XRD, and SEM-EDS, confirm the structural stability and high capture capacity of the adsorbent. Additionally, this study demonstrates the rapid and efficient capture of CO2 from the air using TEPA-Al2O3 adsorbent under high gravity conditions for the first time. Under optimal conditions with TEPA loading at 15.06%, a high gravity factor of 2.67, and a gas flow rate of 30 L/min, TEPA-Al2O3 achieves a CO2 adsorption capacity of 48.5 mg/g in RAB, which is an improvement of 15.56 mg/g compared to traditional fixed-bed technology. Moreover, it reaches adsorption saturation faster under high gravity conditions, exhibiting a significantly higher adsorption rate compared to traditional fixed-bed systems. Furthermore, the adsorption process better conforms to the Avrami model. Steam stripping regeneration is utilized to regenerate the adsorbent, demonstrating excellent regeneration performance and stable adsorption capacity, thereby proving its feasibility and economic benefits as a DAC technology.

Experimental investigation and artificial neural network-based modelling of thermal barrier engine performance and exhaust emissions for methanol-gasoline blends

In recent years, due to environmental concerns and the depletion of fossil fuels, alternative fuel use and alternative emission reduction methods have gained importance in the automotive industry. In addition, methanol is used as an alternative fuel in gasoline engines with coated piston engines. This study first presents an experimental investigation of engine performance and exhaust emissions for a partially thermal barrier lined piston engine operating on methanol-gasoline blends. In the second phase the obtained data is then used to develop an Artificial Neural Network (ANN) based model to predict engine performance and exhaust emissions for methanol-gasoline blends. The developed ANN model was trained and validated using MATLAB. The results of the experimental study showed that the use of methanol-gasoline blended fuel in the engine provides better engine performance and reduced exhaust emissions compared to gasoline fuel. According to the results obtained, an increase of 3.7 % in effective power and a decrease in NOx and HC emissions by 19 % and 18 %, respectively, compared to the STD case when both coating and alternative fuel are used in the engine. With the established ANN models, engine performance parameters and exhaust emission parameters were predicted with 99 % and 98 % accuracy respectively.

Carbon emissions and low-carbon innovation in firms.

Most of the previous studies of environmental innovation focus on the impact of environmental innovation on carbon emissions. This study rarely examines the internal causes and mechanisms of influence of low-carbon innovation. This study focuses on the effect of carbon emissions on low-carbon innovation in firms. Using a panel data set of Chinese A-share firms, this study finds that the increase in carbon emissions promotes low-carbon innovation. This promoting effect comes from high carbon emissions increasing the pressure to reduce carbon emissions in firms and prompting firms to increase R&D investment, and the effect is more pronounced in firms with lower equity concentration or high-tech firms. It is also found that indirect carbon emissions do not promote low-carbon innovation, while other types of carbon emissions do. This study expands the research on the internal causes of low-carbon innovation in firms, examines the logic influencing low-carbon innovation in firms from the perspective of emission reduction motives and methods, reveals that global warming contains opportunities for the development of low-carbon innovation in firms, and provides a reference for optimizing the carbon emissions calculation system.

Study on the Selection of Emission Reduction Methods for Energy-Intensive Enterprises under the Dynamic Carbon Quota Trading Policy

Study on the Selection of Emission Reduction Methods for Energy-Intensive Enterprises under the Dynamic Carbon Quota Trading Policy

Research on Emission Reduction Method Model and Carbon Inclusive Value of Charging Pile Carbon Emission Reduction Service Scenarios

Research on Emission Reduction Method Model and Carbon Inclusive Value of Charging Pile Carbon Emission Reduction Service Scenarios

Silicon nutrition improves the quality and yield of rice under dry cultivation.

Dry cultivation of rice is a water-saving, emission reduction and labor-saving rice farming method. However, the development of rice under dry cultivation is hampered by the limitations of dry cultivation on rice yield and rice quality. We hypothesized that additional silicon (Si) would be a measure to address these limitations or challenges. In the present study, we set up field trials with three treatments: flooded cultivation (W), dry cultivation (D) and dry cultivation plus Si. Yield and quality were reduced under D treatment compared to W treatment. The addition of Si promoted root development, increased plant height and leaf area, increased photosynthetic enzyme activity, net photosynthetic rate and SPAD values, and increased biomass under dry crop conditions. Under the drought conditions, silica up-regulated the expression of AGPSI, SBEI, SBEIIb, SSI and SSII-1 genes and the activities of ADP-glucose pyrophosphorylase (AGPase), soluble starch synthetase (SSS) and starch branching enzyme (SBE) enzymes, which reduced protein, amylose, chalkiness percentage and chalkiness degree, increased brown rice rate, milled rice rate and head milled rice rate, and also improved rice quality. In addition, the increase of AGPase, SSS and SBE enzyme activities promoted the filling rate and the number of spikes was guaranteed, whereas the yield was improved by promoting the seed setting rate and 1000-grain weight. The results of the present study indicate that adding appropriate amounts of Si fertilizer can improve the yield and quality of rice under dry cultivation by regulating source supply capacity and grain starch synthesis. © 2023 Society of Chemical Industry.

Evaluation of energy saving and emission reduction effect of distributed energy system

The conventional evaluation methods of energy conservation and emission reduction lack the discussion of quantification index of energy conservation and emission reduction potential, and the evaluation effect is poor. Therefore, an evaluation method for energy conservation and emission reduction of distributed energy systems is proposed, which considers system dynamics and demand response. According to the requirements of system dynamics analysis, the relational variables in the system dynamics model are determined. The input-output relationship of energy saving, and emission reduction effect evaluation is described by system dynamics equation, and the input-output relationship of energy saving, and emission reduction effect evaluation is determined. Based on the maximum profit objective function and the minimum cost objective function of the user, the continuum equation of the medium transmission process in the distributed energy system is obtained. The evaluation indexes of energy saving, and emission reduction effect are selected from the three aspects of power consumption side, power generation side and the system itself to realize the evaluation of energy saving and emission reduction effect. The experimental results show that the evaluation curve obtained by this method is basically consistent with the actual curve, and the evaluation accuracy is high.

Developing sustainable shipping and maritime transport: Multi-criteria analysis between emission abatement methods

Annual emissions from maritime transport are contributing to the acceleration of global climate change and deteriorating local air quality. Shipowners need information on current and new emission reduction solutions to compare cost-effectiveness and environmental impact. However, emissions reduction in the maritime sector is a complex issue that should also consider the environmental impacts during fuel production and the full impact of different options during use. In this study, different fuel options and emission reduction methods are compared to rank the overall sustainability of alternatives. The overall sustainability assessment is based on the economic and environmental indexes generated, weighted, and aggregated. The results show that the sustainability index of LNG is often the best of the options compared. The difference in fuel prices determines much of the difference in economic performance between fuels. The results emphasize the importance of including several criteria when comparing more sustainable alternatives in shipping.

Determination of Rational Design Values for Gas-Air Coolers Components of Exhaust Gases of Marine Power Plants

Abstract Modernisation of marine power plants in the transport vessel fleet to satisfy the requirements of the International Maritime Organization is an urgent scientific and technical problem. Currently, the use of catalytic selective filters, dry and wet scrubber systems and exhaust gas recirculation for marine diesel engines is widely used for this purpose. An analysis of the use of ejection gas-air coolers is presented as an additional method of emission reduction. However, the use of such device does not neutralise the harmful emissions of power plant engines, but only increases the volume concentration of their exhaust gases. But this will help to increase the efficiency of dispersion of harmful emissions, by reducing the concentration of harmful emissions to values not exceeding the maximum permissible concentrations. Its efficiency depends on the load mode of the diesel engine. It is found that the initial concentration of harmful substances in combustion products due to their dilution with fresh air at 100% engine load is reduced by about 50%. The values of the reduction of the concentration and temperature of exhaust gases with the reduction of the engine load to 75% and 50% depending on the louvre angle are obtained. It is proved that ejection gas-air coolers can be an effective additional means for compliance with modern environmental parameters, especially when vessels are in special areas of the world’s oceans.

Can firms achieve the collaborative governance of airborne pollution and greenhouse gases? Evidence from the Chinese industrial sector

The rapid global industrialization and urbanization processes, especially in developing countries, have caused serious environmental pollution and climate warming. The industrial sector, in which high energy consumption is its main feature, is an important source of airborne pollution and greenhouse gases. The effective realization of collaborative emission reduction in the industrial sector has become an important path worldwide to reduce pollution and carbon in the future. Based on matched data on industrial firms, this study uses a fixed effects model, the two-stage least squares method, quantile regression and an interaction regression model to explore the co-benefits of airborne pollution and greenhouse gas emission reduction from a microscale perspective. Benchmark analysis demonstrates that for every 1% decrease in the airborne pollution emissions of firms, the greenhouse gas emissions of firms decrease by approximately 0.014%. According to heterogeneity analysis, the electric power, heat production and supply industry; the coal mining and washing industry; the leather, fur, feather and related products industry; the ferrous metal ore mining and dressing industry; and the petroleum, coal and other fuel processing industry are ripe for reduction at lower costs. Furthermore, feasibility analysis reveals that firms' sulfur reduction behavior and the government's sulfur reduction legislation may result in collaborative greenhouse gas emission reductions while regulating airborne pollution. This research can help countries meet multiple emission reduction goals by facilitating the optimization of joint emission reduction methods that target numerous pollutants.

Use of Alkali-Activated Slag as an Environment-Friendly Agent for High-Performance Stabilized Soil.

Discharged slag not only occupies a large amount of land for disposal, but also causes serious environmental pollution. The use of alkali-activated slag (AAS) instead of cement as a soil-stabilization agent is beneficial for industrial waste disposal and energy conservation, which complies with the concept of green and low-carbon sustainable development in the construction industry. In this study, the compressive strength, water permeability coefficient, chloride migration coefficient and sulfate resistance of alkali-activated slag-stabilized soil (AASS) were evaluated, and compared with those of cement-stabilized soil (CSS). The hydrated crystalline phases and microscopic pore structures were analyzed by X-ray diffraction, electrochemical impedance spectroscopy (EIS) and mercury intrusion porosimetry (MIP) tests, respectively. The results indicate that, compared with CSS, AASS exhibits a higher compressive strength, lower water permeability, chloride migration coefficient and better resistance to sulfate attack, with the optimum dosage higher than 10 wt.%. The results of the MIP analysis show that the addition of AAS reduces the porosity by 6.47%. The combined use of soil and AAS proves to be a viable and sustainable method of waste utilization and carbon emission reduction in the construction industry, which provides a practical path towards carbon peaking and carbon neutrality.

Life cycle assessment and multi-objective optimization for industrial utility systems

Utility systems, which are energy and CO2 intensive, provide power and heat for the industrial process. Modeling, assessing, and optimization of utility systems can help promote sustainable development. This paper proposed a life cycle assessment-based multi-objective optimization framework to address this issue. First, measures for saving energy and reducing emissions were proposed to improve the utility system. The semi-empirical models of the basic components in the improved utility system are developed using process mechanisms and historical data. Secondly, the theory of life cycle assessment (LCA) is employed to evaluate the environmental impacts comprehensively. The operating cost and environmental impact models of the system are then developed and solved by a weighted multi-objective optimization method. Finally, a case study from an industrial utility system is implemented to verify the effectiveness of the proposed method, and three scenarios with different emission reduction methods are compared. In the scenario with two emission reduction measures, it shows that the maximum reduction of environmental impacts could be 56.59%, while the operating cost increases by 36.17%. The Pareto frontiers of the three scenarios provide several choices to balance the operating cost and environmental impacts.

Research on Greenhouse Gas Emission Reduction Methods of SBR and Anoxic Oxic Urban Sewage Treatment System

With the rising awareness of environmental protection, more sewage treatment plants have been built. However, this is also one of the main sources of greenhouse gas emissions. This study carried out a series of sewage treatment experiments to analyze the factors affecting the greenhouse gas emissions of the two commonly used treatment processes in the current urban sewage treatment: the A/O and SBR methods. The experimental results showed that the total amount of greenhouse gases emitted by the A/O method was 415.63 gCO2-eq/m3, and the total amount of greenhouse gases emitted by the SBR method was 879.51 gCO2-eq/m3. The N2O emission factor in the A/O method experimental group was 0.76% of the nitrogen content in the influent. In the aerobic section, when the content of dissolved oxygen was in the range of 1.30~2.10 mg/L, and the content of dissolved oxygen was 1.90 mg/L, the minimum N2O emission factor was reduced to 0.29% of the nitrogen content of the influent. In the SBR experimental group, the ammonia oxidation rate of sewage decreased rapidly as the temperature decreased, thus affecting the discharge rate of N2O. At 25 °C, the biological enzyme activity of nitrifying bacteria was higher, thus promoting denitrification and generating more greenhouse gases. The research results provide reference for strengthening the management of sewage treatment plants and reducing greenhouse gas emissions from sewage treatment plants.

The Roles of Carbon Trading System and Sustainable Energy Strategies in Reducing Carbon Emissions—An Empirical Study in China with Panel Data

Carbon emission reduction is now a vital element in urban development. This study explores the effectiveness of the two emerging methods to reduce carbon emission, which are carbon emissions trading system (ETS) and sustainable energy strategy, in the process of urbanization. We review the policy in the past decades to demonstrate the development of these two streams of carbon emission reduction methods and empirically test the effectiveness of the two methods with panel data across 30 provinces in China from 2009 to 2019. The sustainable energy strategy is confirmed to be effective in reducing carbon emissions in the region, while the effectiveness of carbon emissions trading system varies. We find that (1) substituting fossil fuel with other sustainable energy resources can effectively reduce the carbon emission; (2) the rewards from carbon emissions trading is a good incentive for the enterprises to reduce the carbon emissions; however, it is more tempting in the provinces that have the carbon emissions trading system, although the trading can be conducted across the province boarder. Our findings indicate that the sustainable energy strategy is a good practice and worth expanding to the whole country. It can be difficult for some provinces to transform and adopt the sustainable energy strategy if the fossil fuel is the major source for economic production. It is important to avoid setting fossil fuel as the main source for economic production or household consumption in the urbanization process. Meanwhile the carbon emissions trading system is found to contribute to CO2 emissions reduction only within the province. Therefore, having more provinces piloting the ETS will help the CO2 emission reduction further.

Comparative study of greenhouse gas emission calculations and the environmental impact in the life cycle assessment of buildings in China, Finland, and the United States

The building sector is considered a leading contributor to global greenhouse gas (GHG) emissions. With the implementation of China's 2030 carbon peak and 2060 carbon-neutral strategy, significant quantitative research regarding low-carbon buildings is crucial. However, a considerable discrepancy remains between the low-carbon building development in China and other advanced countries; the calculation method of GHG emissions lacks international integration. Based on the life cycle assessment (LCA) theory, a comparative empirical analysis was conducted among residential and public building sets in China, Finland, and the United States considering the life-cycle GHG emissions, which demonstrated notable differences in the Product stage (A1–A3), Maintenance and material replacement stage (B1–B5), and Energy use stage (B6) between each building set. Different building retrofit scenarios were then established to study the emission reduction methods. The results suggest that clean energy sources, materials with low global warming potential, engineered wood structures, and steel structural beams in long-span buildings are conducive to reducing GHG emissions throughout the life-cycle of buildings.