World Journal of Environmental Science and Engineering is an international, peer-reviewed open access journal dedicated to advancing research the field of environmental science and engineering. The journal provides a rapid publication process to ensure wide dissemination of high-quality articles to scientists, professionals, and interested individuals worldwide. Our goal is to serve as an efficient, reliable, and trusted platform for scholars and readers, publishing cutting-edge research in the field.
Abstract: Mining under the Ordovician limestone aquifer is severely threatened by coal seam floor water inrush, which endangers mining safety. Traditional fixed-weight evaluation models for coal floor water inrush risk have prominent limitations: they ignore the internal variability among index values, easily distorting prediction results and failing to meet the demand for accurate risk assessment. To address this issue, this study proposes a dynamic variable weight evaluation model for coal floor water inrush risk based on the Improved Fuzzy Analytic Hierarchy Process (IFAHP) and Entropy Weight Method (EWM). First, after comprehensive analysis of hydrogeological data, six key evaluation indicators were selected, including Ordovician limestone water pressure, Ordovician limestone water abundance, aquifuge thickness, fragile rock ratio, fault fractal dimension, and floor failure depth. Subjective weights from IFAHP and objective weights from EWM were then combined to obtain comprehensive weights. Subsequently, the K-means algorithm was applied for unified clustering analysis of the indices to define variable weight intervals and construct the dynamic variable weight model. Based on this model, ArcGIS was used to classify Ordovician limestone water inrush risk into four levels and generate a risk zoning map for the 16th coal seam floor. Validation with known water inrush points and comparative analysis with the constant-weight model demonstrated that the proposed IFAHP-EWM dynamic variable weight method has higher prediction accuracy and better spatial adaptability. Additionally, 3D visualization of the risk zoning map was developed to enhance practical application. This model provides a reliable theoretical basis and practical tool for improving the safety of coal seam floor mining under Ordovician limestone aquifers.Abstract: Mining under the Ordovician limestone aquifer is severely threatened by coal seam floor water inrush, which endangers mining safety. Traditional fixed-weight evaluation models for coal floor water inrush risk have prominent limitations: they ignore the internal variability among index values, easily distorting prediction results and failing to meet...Learn More
Abstract: Polyethylene terephthalate (PET) is one of the most widely produced synthetic polymers, extensively used in beverage bottles, food packaging, and textile fibers due to its excellent mechanical strength, transparency, and chemical resistance. However, the massive consumption of PET has generated an escalating global plastic waste crisis. Mechanical recycling remains the dominant strategy for PET waste management, yet it suffers from polymer degradation, contamination sensitivity, and limited recyclability. Chemical recycling has therefore emerged as a promising approach to close the carbon loop by converting PET waste into its constituent monomers or other high-value chemicals. In recent years, significant progress has been achieved in catalytic depolymerization strategies including glycolysis, methanolysis, hydrolysis, aminolysis, and hydrogenolysis. In addition, emerging approaches such as enzymatic depolymerization, solvent-assisted recycling, and tandem catalytic upgrading have further expanded the valorization potential of PET waste. This review provides a comprehensive overview of recent advances in PET chemical recycling, focusing on reaction mechanisms, catalytic systems, process intensification strategies, and product upgrading pathways. Special emphasis is placed on heterogeneous catalysis, green solvents, and integrated catalytic systems for converting PET into monomers such as terephthalic acid and ethylene glycol or into value-added chemicals including fuels, polymers, and aromatic compounds. Finally, current challenges and future research directions are discussed, highlighting opportunities for designing sustainable catalytic systems and scalable industrial processes for circular plastic economy.Abstract: Polyethylene terephthalate (PET) is one of the most widely produced synthetic polymers, extensively used in beverage bottles, food packaging, and textile fibers due to its excellent mechanical strength, transparency, and chemical resistance. However, the massive consumption of PET has generated an escalating global plastic waste crisis. Mechanical ...Learn More
