Inventory Routing Problem (IRP) has been continuously developed and improved due to pressure from global warming issue particularly related to greenhouse gases (GHGs) emission. The burning of fossil fuel for transportations such as cars, trucks, ships, trains, and planes primarily emits GHGs. Carbon dioxide (CO2) from burning of fossil fuel to power transportation and industrial process is the largest contributor to global GHGs emission. Therefore, the focus of this study is on solving a multi-period inventory routing problem (MIRP) involving carbon emission consideration based on carbon cap and offset policy. Hybrid genetic algorithm (HGA) based on allocation first and routing second is used to compute a solution for the MIRP in this study. The objective of this study is to solve the proposed MIRP model with HGA then validate the effectiveness of the proposed HGA on data of different sizes. Upon validation, the proposed MIRP model and HGA is applied on real-world data. The HGA is found to be able to solve small size and large size instances effectively by providing near optimal solution in relatively short CPU execution time.
The fate of humankind and all other life forms on earth is threatened by a foe, known as climate change. All parts of the world are affected directly or indirectly by this phenomenon. The rivers are drying up in some places and in other places, it is flooding. The global temperature is rising every year and the heat waves are taking many souls. The cloud of "extinction" is upon the majority of flora and fauna; even humans are prone to various fatal and life-shortening diseases from pollution. This is all caused by us. The so-called "development" by deforestation, releasing toxic chemicals into air and water, burning of fossil fuels in the name of industrialisation, and many others have made an irreversible cut in the heart of the environment. However, it is not too late; all of this could be healed back with the help of technology and our efforts together. As per the international climate reports, the average global temperature has increased by a little more than 1 °C since 1880s. The research is primarily focused on the use of machine learning and its algorithm to train a model that predicts the ice meltdown of a glacier, given the features using the Multivariate Linear Regression. The research strongly encourages the use of features by manipulating them to determine the feature with a major impact on the cause. The burning of coal and fossil fuels is the main source of pollution as per the study. The research focuses on the challenges to gather data that would be faced by the researchers and the requirement of the system for the development of the model. The study is aimed to spread awareness in society about the destruction we have caused and urges everyone to come forward and save the planet.
The world faces immense pressure regarding the negative impacts of increased greenhouse gas emissions, climate change, global warming, droughts, and many other environmental problems. Australia is also facing the same issues and requires urgent attention. In this research, we have examined the effect of hydrogen firms on Australia's greenhouse gas emissions. We employed the monthly data from January 2002 to December 2021 for econometric estimations. Through quantile regression, it is noted that the expansion of hydrogen firms contributes to environmental pollution instead of controlling the emissions. Most hydrogen energy still emits carbon dioxide, which contributes to climate change. Around the world, carbon-containing fossil fuels produce more than 95% of hydrogen energy. However, as a policy suggestion, it is recommended that green hydrogen produced by electrolysis of water using renewable energy sources will succeed in achieving the Sustainable Development Goals (SDGs).
Industrial revolution on the back of fossil fuels has costed humanity higher temperatures on the planet due to ever-growing concentration of carbon dioxide emissions in Earth's atmosphere. To tackle global warming demand for renewable energy sources continues to increase. Along renewables, there has been a growing interest in converting carbon dioxide to methanol, which can be used as a fuel or a feedstock for producing chemicals. The current review study provides a comprehensive overview of the recent advancements, challenges and future prospects of methanol production and purification via membrane-based technology. Traditional downstream processes for methanol production such as distillation and absorption have several drawbacks, including high energy consumption and environmental concerns. In comparison to conventional technologies, membrane-based separation techniques have emerged as a promising alternative for producing and purifying methanol. The review highlights recent developments in membrane-based methanol production and purification technology, including using novel membrane materials such as ceramic, polymeric and mixed matrix membranes. Integrating photocatalytic processes with membrane separation has been investigated to improve the conversion of carbon dioxide to methanol. Despite the potential benefits of membrane-based systems, several challenges need to be addressed. Membrane fouling and scaling are significant issues that can reduce the efficiency and lifespan of the membranes. The cost-effectiveness of membrane-based systems compared to traditional methods is a critical consideration that must be evaluated. In conclusion, the review provides insights into the current state of membrane-based technology for methanol production and purification and identifies areas for future research. The development of high-performance membranes and the optimization of membrane-based processes are crucial for improving the efficiency and cost-effectiveness of this technology and for advancing the goal of sustainable energy production.
The objective of the study is to examine the relationship between air pollution, fossil fuel energy consumption, water resources, and natural resource rents in the panel of selected Asia-Pacific countries, over a period of 1975-2012. The study includes number of variables in the model for robust analysis. The results of cross-sectional analysis show that there is a significant relationship between air pollution, energy consumption, and water productivity in the individual countries of Asia-Pacific. However, the results of each country vary according to the time invariant shocks. For this purpose, the study employed the panel least square technique which includes the panel least square regression, panel fixed effect regression, and panel two-stage least square regression. In general, all the panel tests indicate that there is a significant and positive relationship between air pollution, energy consumption, and water resources in the region. The fossil fuel energy consumption has a major dominating impact on the changes in the air pollution in the region.
Although nutrient removal and recovery from municipal wastewater are desirable to protect phosphorus resource and water-bodies from eutrophication, it is unclear how much environmental and economic benefits and burdens it might cause. This study evaluated the environmental and economic life cycle performance of three different upgraded Processes A, B and C with commercially available technologies for nutrient removal and phosphorus recovery based on an existing Malaysian wastewater treatment plant with a sequencing batch reactor technology and diluted municipal wastewater. It is found that the integration of nutrient removal, phosphorus recovery and electricity generation in all upgraded processes reduced eutrophication potential by 62-76%, and global warming potential by 7-22%, which, however, were gained at the cost of increases in human toxicity, acidification, abiotic depletion (fossil fuel) and freshwater ecotoxicity potentials by an average of 23%. New technologies for nutrient removal and phosphorus recovery are thus needed to achieve holistic rather than some environmental benefits at the expense of others. In addition, the study on two different functional units (FU), i.e. per m3 treated wastewater and per kg struvite recovered, shows that FU affected environmental assessment results, but the upgraded Process C had the least overall environmental burden with either of FUs, suggesting the necessity to use different functional units when comparing and selecting different technologies with two functions such as wastewater treatment and struvite production to confirm the best process configuration. The total life cycle costs of Processes A, B and C were 10.7%, 29.8% and 28.1%, respectively, higher than the existing process due to increased capital and operating costs. Therefore, a trade-off between environmental benefits and cost has to be balanced for technology selection or new integrated technologies have to be developed to achieve environmentally sustainable wastewater treatment economically.
This paper empirically examines the effects of energy, natural resources, agriculture, political constraint and regional integration on CO2 emissions in four ASEAN (Association of Southeast Asian Nations) countries of Cambodia, Malaysia, Indonesia and Thailand. We distinguish between renewable and fossil fuel energy consumption to see their individual impacts on CO2 emissions. The study employed a panel data from 1990 to 2019 derived from sources such as World Development Indicators, which were then analysed using Common-Correlated Effect Mean Group (CCEMG) and Augmented Mean Group (AMG) estimates. The findings show that renewable energy consumption has a negative impact on CO2 emissions while fossil fuel energy degrades the environment. The role of natural resources was found to be favourable for environmental quality with the impact of agriculture being found to be detrimental. For regional trade integration, its influence was not significant enough to offset CO2 emission. Furthermore, we discovered that political constraint induces CO2 emission. Based on the result, it is recommended that the selected ASEAN countries promote the use of renewable energy and clean technologies in their manufacturing processes, conserve natural resources, adopt eco-friendly political policies and intensify regional integration to accelerate the achievement of the SDGs.
The Belt and Road Initiative (BRI) is an ambitious development project initiated by the Chinese government to foster economic progress worldwide. In this regard, this study aims to investigate the dynamics of energy, economy, and environment among 42 BRI developing countries using an annual frequency panel dataset from 1995 to 2019. The major findings from the econometric analyses revealed that higher levels of energy consumption, economic growth, population growth rate, and FDI inflows exhibit adverse environmental consequences by boosting the CO2 emission figures of the selected developing BRI member nations. However, it is interesting to observe that exploiting renewable energy sources, which are relatively cleaner compared to the traditionally-consumed fossil fuels, and fostering agricultural sector development can significantly improve environmental well-being by curbing the emission levels further. On the other hand, financial development is found to be ineffective in explaining the variations in the CO2 emission figures of the selected countries. Besides, the causality analysis shows that higher energy consumption, FDI inflows, and agricultural development cause environmental pollution by boosting CO2 emissions. However, economic growth, technology development, financial progress, and renewable energy consumption are evidenced to exhibit bidirectional causal associations with CO2 emissions. In line with these findings, several relevant policies can be recommended for the BRI to be environmentally sustainable.
A key objective of renewable energy development in the USA is to reduce CO2 emissions by decreasing reliance on fossil fuels in the coming decades. Using quantile-on-quantile regressions, this research examines the relationship between disaggregated sources of renewable energy (biomass, biofuel, geothermal, hydroelectric, solar, wind, wood, and waste) and CO2 emissions in the USA during the period from 1995 to 2017. Our findings support the deployment of various types of renewables in combating CO2 emissions for each quantile. In particular, a negative effect of renewable energy consumption on CO2 emissions is observed for the lower quantiles in almost all types of renewables. The effect of all the renewable energy sources taken together is significant for the lower and upper quantiles of the provisional distribution of CO2 emissions. The effect of renewable energy becomes stronger and more significant in the middle quantiles, where a pronounced causal effect of return and volatility is detected for the lower and upper middle quantiles. At the same time, heterogeneity in the findings across various types of renewable energy sources reveals differences in the relative importance of each type within the energy sector taken as a whole. Future US initiatives in renewable energy deployment at both the federal and the state levels should take into consideration the relative importance of each type, so as to maximize the efficacy of renewable energy policies in combating CO2 emissions.
The energy profile of India is dominated by fossil fuels, which create concerns over resource and environmental sustainability as fossil fuels are non-renewable and high carbon emitting. This scenario has necessitated the call for more renewables to replace fossil fuels to address resource and environmental sustainability concerns. This study, therefore, investigates the possibility of switching the fossil fuels of oil, coal, and natural gas for renewable energy in India. Using annual Indian data spanning more than four decades, a transcendental logarithmic production function based on a second-order Taylor Series approximation is estimated with the ridge regression technique. To achieve robustness, two equations with gross domestic product and adjusted net savings as regressands are estimated to proxy economic growth and sustainable development, respectively. The empirical results show substantial substitution possibilities between the fuels for both gross domestic product and adjusted net savings equations. The empirical findings show that India has the capacity to satisfy its energy needs through renewables to pursue not only economic growth but sustainable development. To actualize this potential, the Indian government should promote investment in renewables as this also promotes economic growth and development.
The objective of the study is to extend the existing literature by investigating the effects of foreign direct investment, gross domestic products and per capita and energy diversification on the nitrogen oxide emissions in Brazil, Russia, India, China and South Africa (BRICS) by using annual data during the period 1992-2019. As per our knowledge, the present study is a first of its kind to examine the impact of a new energy diversification index, based on Herfindahl-Hirschman framework on pollution. This study has adopted a new quantile regression augmented method of moments, which is capable of producing the total impacts of the independent variables across the entire distribution of nitrogen oxides emissions. The findings suggest that an increase in foreign direct investment leads to a decrease in nitrogen oxides emissions at the aggregate level and in both manufacturing and service sectors. We observe that foreign direct investment leads to an increase in nitrogen oxides emissions in the agricultural sector in most of the quantiles. Diversification towards renewable energy causes a decrease in nitrogen oxides emissions in most quantiles at aggregate level, agricultural and manufacturing sectors, whilst diversification leads to an increase in nitrogen oxides emissions in the service sector. The findings also suggest that GDP per capita leads to an increase in NOx emissions in all the quantiles. The study suggests the policy to use and attract more clean energy through foreign direct investment for towards the achievement of sustainable development.
This paper seeks to answer an empirical question of whether clean biomass energy consumption lowers CO2 emissions while controlling for technical innovation in eight selected countries from Africa for the 1980-2015 period. The countries which are chosen based on availability of data on biomass energy and technological innovation include Egypt, Algeria, South Africa, Mauritius, Kenya, Morocco, Tunisia, and Zambia. Applying pooled mean group, mean group, and dynamic fixed effect panel estimators, the results indicate that clean biomass energy use decreases CO2 emission in the long run. But the effect of biomass energy consumption on CO2 emission is insignificant in the short run. The findings imply that CO2 emission can be reduced by increasing clean biomass energy in the energy mix of these countries. Similarly, environmental quality and economic growth can be achieved simultaneously by increasing the share of biomass energy in large-scale production process. Furthermore, the environmental Kuznets curve (EKC), which hypothesizes an inverted U-shaped relationship between CO2 emission and economic growth, was validated in the long run. This suggests that the EKC pattern is only observed in the long run. Thus, as part of recommendation from this study, policy makers in these countries should formulate more policies that will enhance clean biomass energy production and its usage to substitute significant percentage of fossil fuel use in production process.
Third generation biofuels, also known as microalgal biofuels, are promising alternatives to fossil fuels. One attractive option is microalgal biodiesel as a replacement for diesel fuel. Chlamydomonas sp. Tai-03 was previously optimized for maximal lipid production for biodiesel generation, achieving biomass growth and productivity of 3.48 ± 0.04 g/L and 0.43 ± 0.01 g/L/d, with lipid content and productivity of 28.6 ± 1.41% and 124.1 ± 7.57 mg/L/d. In this study, further optimization using 5% CO2 concentration and semi-batch operation with 25% medium replacement ratio, enhanced the biomass growth and productivity to 4.15 ± 0.12 g/L and 1.23 ± 0.02 g/L/d, with lipid content and productivity of 19.4 ± 2.0% and 239.6 ± 24.8 mg/L/d. The major fatty acid methyl esters (FAMEs) were palmitic acid (C16:0), oleic acid (C18:1), and linoleic acid (C18:2). These short-chain FAMEs combined with high growth make Chlamydomonas sp. Tai-03 a suitable candidate for biodiesel synthesis.
A comprehensive study of the chemical composition of rainwater was carried out from October 2016 to September 2017 in the equatorial tropical rainforest region of northwestern Borneo. Monthly cumulative rainwater samples were collected from different locations in the Limbang River Basin (LRB) and were later categorized into seasonal samples representing northeast monsoon (NEM), southwest monsoon (SWM), and inter-monsoon (IM) periods. Physical parameters (pH, EC, TDS, DO, and turbidity), major ions (HCO3-, Cl-, Ca2+, Mg2+, Na+, and K+) and trace metals (Co, Ni, Cd, Fe, Mn, Pb, Zn, and Cu) were analyzed from collected rainwater samples. Rainwater is slightly alkaline with mean pH higher than 5.8. Chloride and bicarbonate are the most abundant ions, and the concentration of major ions in seasonal rainwater has shown slight variation which follows a descending order of HCO3-> Cl-> Na+ > Ca2+ > Mg2+ > K+ in NEM and Cl- > HCO3- > Na+ > Ca2+ > K+ > Mg2+ in SWM and Cl- > HCO3- > Na+ > Ca2+ > Mg2+ > K+ in IM period. Trace metals such as Fe and Ni have shown dominance in seasonal rainwater samples, and all the metals have shown variation in concentration in different seasons. Variation in chemical characteristic of seasonal rainwater samples identified through piper diagram indicates dominance of Ca2+-Mg2+-HCO3- and mixed Ca2+-Mg2+-Cl- facies during NEM, SWM, and IM periods. Statistical analysis of the results through two-way ANOVA and Pearson's correlation also indicates significant variation in physico-chemical characteristics. This suggests a variation in contributing sources during the monsoon seasons. Factor analysis confirmed the source variation by explaining the total variance of 79.80%, 90.72%, and 90.52% with three factor components in NEM, SWM, and IM rainwater samples with different loading of parameters. Enrichment factor analysis revealed a combined contribution of marine and crustal sources except K+ which was solely from crustal sources. Sample analysis of backward air mass trajectory supports all these findings by explaining seasonal variation in the source of pollutants reaching the study area. Overall, the results show that the chemical composition of seasonal rainwater samples in LRB was significantly influenced by natural as well as anthropogenic processes. These include (long-range and local) industrial activities, fossil fuel combustion, forest burning, transportation activities including road transport and shipping activities, and land-derived soil dust along with chemical constituents carried by seasonal wind.
Global warming has become a serious issue nowadays as the trend of CO2 emission is increasing by years. In Malaysia, the electricity and energy sector contributed a significant amount to the nation's CO2 emission due to fossil fuel use. Many research works have been carried out to mitigate this issue, including carbon capture and utilization (CCUS) technology and biological carbon fixation by microalgae. This study makes a preliminary effort to screen native microalgae species in the Malaysian coal-fired power plant's surrounding towards carbon fixation ability. Three dominant species, including Nannochloropsis sp., Tetraselmis sp., and Isochrysis sp. were identified and tested in the laboratory under ambient and pure CO2 condition to assess their growth and CO2 fixation ability. The results indicate Isochrysis sp. as the superior carbon fixer against other species. In continuation, the optimization study using Response Surface Methodology (RSM) was carried out to optimize the operating conditions of Isochrysis sp. using a customized lab-scale photobioreactor under simulated flue gas exposure. This species was further acclimatized and tested under actual flue gas generated by the power plant. Isochrysis sp. had shown its capability as a carbon fixer with CO2 fixation rate of 0.35 gCO2/L day under actual coal-fired flue gas exposure after cycles of acclimatization phase. This work is the first to demonstrate indigenous microalgae species' ability as a carbon fixer under Malaysian coal-fired flue gas exposure. Thus, the findings shall be useful in exploring the microalgae potential as a biological agent for carbon emission mitigation from power plants more sustainably.
Dwindling fossil fuels and improper waste management are major challenges in the context of increasing population and industrialization, calling for new waste-to-energy sources. For instance, refuse-derived fuels can be produced from transformation of municipal solid waste, which is forecasted to reach 2.6 billion metric tonnes in 2030. Gasification is a thermal-induced chemical reaction that produces gaseous fuel such as hydrogen and syngas. Here, we review refuse-derived fuel gasification with focus on practices in various countries, recent progress in gasification, gasification modelling and economic analysis. We found that some countries that replace coal by refuse-derived fuel reduce CO2 emission by 40%, and decrease the amount municipal solid waste being sent to landfill by more than 50%. The production cost of energy via refuse-derived fuel gasification is estimated at 0.05 USD/kWh. Co-gasification by using two feedstocks appears more beneficial over conventional gasification in terms of minimum tar formation and improved process efficiency.
This study was performed to observe the variation in the distribution of 210Po,210Pb and 210Po/210Pb activity ratio throughtheir vertical profile of the sediment cores takenat surrounding Sungai Linggi estuary. Five sediment cores were takenin February 2011 and were cutto an intervalof 2 cm layer. Activity concentrations of 210Po and 210Pb were determined using alpha radiochemical analysis and gamma direct measurement, respectively. Generally, the measured activity of 210Po, 210Pb and 210Po/210Pbwere in the ranges of 22.73 –139.06 Bqkg-1dw., 37.88 –176.24 Bqkg-1dw.and 0.23 –1.34, respectively. The variation in the distribution profile for the radionuclides are believed to be influencedby human activities such as agriculture, fertilizer, vehicles, burned fuel fossil and forest, industrialand others via river input from land-base.Other factor is due to organic mattercontent played importantrole as the geochemical carrier to transportthose radionuclides at study area. It was provedthat hasa strong correlation between the radionuclide distribution and the sedimentcomposition of organic matter.Furthermore, in those rangesreflectedthat 210Pb activities were higher than210Po with an activity ratio average of 0.79. This is probably due to dramatic increase of excess 210Pb supplied from atmospheric deposition, in situ decay of 226Ra and as a result of diagenetic remolibilazationof 210Pbin deeper layesof the sediment column. Thus, thosefactors are majorcontributions on thevariation of 210Po and 210Pb in the sediment core at surrounding Sungai Linggi estuary.
The increasing degradation of fossil fuels has motivated the globe to turn to green energy solutions such as biofuel in order to minimize the entire reliance on fossil fuels. Green renewable resources have grown in popularity in recent years as a result of the advancement of environmental technology solutions. Kapok fiber is a sort of cellulosic fiber derived from kapok tree seeds (Ceiba pentandra). Kapok Fiber, as a bio-template, offers the best alternatives to provide clean and renewable energy sources. The unique structure, good conductivity, and excellent physical properties exhibited by kapok fiber nominate it as a highly favored cocatalyst for deriving solar energy processes. This review will explore the role and recent developments of KF in energy production, including hydrogen and CO2 reduction. Moreover, this work summarized the potential of kapok fiber in environmental applications, including adsorption and degradation. The future contribution and concerns are highlighted in order to provide perspective on the future advancement of kapok fiber.
There is a growing interest in developing bio-based biodegradable plastics to reduce the dependence on depleting fossil fuels and provide a sustainable alternative. Bio-based plastics can usually be produced from lipids, proteins or carbohydrates, which are major components of microalgae. Despite its potential for algal plastics, little information is available on strain selection, culture optimization and bioplastics fabrication mechanism. In this review, we summarized the recent developments in understanding the utilization of seaweed polysaccharides, such as alginate and carrageenan for bio-based plastics. In addition, a conceptual biorefinery framework for algal plastics through promising components (e.g., lipids, carbohydrates and proteins) from microalgae is comprehensively presented. Moreover, the reasons for variations in bioplastics performance and underlying mechanism of various algal biocomposites have been critically discussed. We believe this review can provide valuable information to accelerate the development of innovative green technologies for improving the commercial viability of algal plastics.