Environmental, technological, and economic analysis of supercritical coal-fired power system.

Developing countries primarily rely on fossil-based energy sources to meet their energy demands. The use of fossil fuels has several adverse environmental repercussions that damage the biosphere both directly and indirectly. Among fossil fuels, coal brings about the heaviest environmental externalities, yet its abundance makes its use widespread, particular in countries having significant power generation deficits, such as Pakistan. This study presents an environmental, technological, and economic analysis of a supercritical coal-based power unit located in Pakistan and used for electricity generation. For environmental assessment, the CML-1A baseline method in OpenLCA software was used, and eight midpoint impact indicators were selected. The functional unit chosen was 1 MWh of generated electricity. The results indicated that the category of ozone layer depletion has the least impact, whereas global warming potential has the highest impact score. Except for photochemical oxidation and human toxicity, the plant operational stage dominated most of the selected impact categories. The current paper also reveals that the removal efficiency of CO2 and other pollutants is higher in supercritical compared to subcritical plants. Moreover, the economic feasibility of supercritical plant is compared with chemical looping combustion (CLC)-based supercritical coal-fired power plant, and results shows that CLC-based coal-fired power plant is a more competitive and environmentally friendly option. The utilization of a scientific cleaner energy-management system in real-time, as exemplified in this study, may facilitate the development of a optimal policy framework that encourages for the adoption of cleaner coal power generation in developing countries, ultimately resulting in improved energy sustainability. Furthermore, this paper also presents some policy implications which could be helpful for policymakers, researchers, and industrialists to improve the sustainability of energy in emerging economies.

Overview of environmental and economic viability of activated carbons derived from waste biomass for adsorptive water treatment applications.

In adsorptive water treatment applications, the exploration of waste-derived activated carbon (AC) has gained substantial attention in scientific research. The use of waste materials as precursors for AC has gained attention due to its economic viability and potential to reduce the consumption of non-renewable resources. However, there is a lack of comprehensive literature regarding the costs and environmental impacts associated with the waste-based AC production and application. As sustainability practices gain importance, there has been an increase in research dedicated to estimating costs and conducting life cycle assessment (LCA) of AC production from waste sources. However, there is a need for thorough literature reviews that cover various methodologies and conclusions. The primary objective of this study is to provide a comprehensive overview and analysis of the economic and environmental factors related to the use of waste-derived AC in water treatment. LCA studies indicate that utilizing waste materials for AC production can lead to significant resource and energy savings compared to conventional methods relying on fossil resources. The cost of AC is influenced by factors such as precursor material cost, energy requirements during production (optimizable on an industrial scale), and properties of the resulting material. Additionally, the review emphasizes the significance of waste-based AC regeneration for sustainable viability. Evaluating the environmental and economic costs is crucial to support sustainability claims and avoid unsupported assertions. Overall, this study contributes to understanding the potential of waste-derived AC in water treatment and highlights the need for further research in this area.

Underground geological sequestration of carbon dioxide (CO2) and its effect on possible enhanced gas and oil recovery in a fractured reservoir of Eastern Potwar Basin, Pakistan.

Due to concerns over rising emissions of carbon dioxide (CO2) from fossil fuel utilization, there has been a strong emphasis on the development of a safe, economical, practical method of carbon capture utilization and storage (CCUS). One way to reduce these CO2 emissions is underground geological sequestration in depleted oil fields or exhausted reservoirs. CO2 injection into oil reservoirs is an established technology, these reservoirs not only offer the potential for high storage of CO2 but this process could also target a large amount of oil and gas recovery through a technique called enhanced oil recovery (EOR). The main objective of this research was to evaluate the storage potential of CO2 in the depleted oil field while also investigating the effect of CO2 injection on reservoir pressure maintenance, and additional oil and gas recovery, in the same field. This paper presented the model of CO2 flooding based on the CO2 displacement mechanism with different scenarios of natural depletion, CO2 injection, and water injection simulated by the ECLIPSE 300 reservoir simulator, and the results of different scenarios were compared. Results of this study showed the site selected for CO2 injection has the potential to store more than 9 billion cubic feet (BCF) of CO2 in each case and witnessed improved gas recovery, while also having a major effect on reservoir pressure maintenance where pressure increased from 2120 psi to 6584 psi. The finding of this work ought to help in preparing for future improvement in underground geological sequestration of CO2 in depleted fields with the same field specifications.