Transformers reduce the voltage from overhead powerlines to voltages acceptable for city/neighbourhood needs. Overheating of transformer cooling fluids presents a serious hazard. In this work, the risk of fires and explosions due to vaporisation of the hydrocarbon components of mineral oil, which is used as a transformer cooling fluid in electrical substations, was investigated. The compositions of new and used mineral oil from an electrical substation in Riyadh were analysed using gas chromatography–mass spectrometry, and C₆ to C₄₁ hydrocarbons were detected. The majority of the components were alkanes, alkenes, or alkynes; some ketone, alcohol, aromatic, and anhydride species were also detected. Approximately 25% of the compounds comprising the new oil sample were alkanes, whereas more than 33% of the used oil sample components were alkanes. The lower and upper flammability limits (LFL and UFL) of the mixtures were found to be 0.88 and 5.75 vol.% for the new oil and 0.47 and 3.05 vol.% for the used oil, respectively. These values were used to construct a flammability diagram. The results indicated that the new and used oil vapour mixtures were not flammable at 25 °C and 1 atm, but would become flammable at 77 and 115 °C.

This study aims to find how fires and explosions can occur in enclosed spaces where electrical transformers are installed and to investigate the consequences of the damages to the surrounding areas caused by these accidents. This study began with the collection of a mineral oil waste sample from an indoor substation transformer in Riyadh, Saudi Arabia. This sample was analyzed to determine its composition. Results revealed that 30 components ranging from C₆ to C₃₀ were detected in the sample. The mixture flammability limits, calculated using Le Chatelier rules and found to be 0.97 and 6.56, indicated that the vapor mixture for the waste oil sample was not flammable at 25 °C and 1 atm. Consequence analysis was used to predict the outcome of fire and explosion events based on a transformer with a capacity of 1100 liters. The peak overpressure generated by an explosion was estimated to be 80.97 kPa. Moreover, the thermal radiation produced by various types of fires was estimated as a function of the distance from the accident center. The thermal flux from a boiling liquid expanding vapor explosion (BLEVE) was 99.8 kW/m², which is greater than that from jet and pool fires. The probability of an individual suffering injury or dying as a result of exposure to fire and/or an explosion was estimated using dose-response models. The results showed that the peak overpressure produced by an explosion can cause severe damage within 20 m of the explosion center. However, the results also showed that there is a 100% probability of the thermal radiation from a BLEVE causing fatalities up to a distance of 140 m. The risk due to the fragmentation of the transformer tanks was also assessed, and a majority of fragments would land within a range of 111.2 m.

This study presents novel life cycle assessment (LCA) findings on hydrochar production from Saudi-Arabia-based date palm fronds biomass waste using hydrothermal carbonization (HTC). The LCA procedure incorporated normalization, weighting, and improvement assessment. The system boundary encompassed water consumption and energy requirements within a lab setting representing a gate-to-gate process. The OpenLCA 1.11.0 software with the European Life Cycle Database 3.2 (ELCD 3.2) was utilized for the study and we employed the ReCiPe Midpoint (H) 2016 and Environmental Footprint 3.0 (EF 3.0) impact assessment methods. The results indicated that fossil fuel usage represented the most significant impact category with the HTC and drying processes identified as major contributors. It was also observed that the HTC process exerted far greater detrimental impacts on the environment than the biomass grinding process. The overwhelming impact of fossil fuel resources could be mitigated by optimizing the batches of biomass or hydrochar samples in each operation, which could alleviate fossil fuel consumption by up to 94%. The findings emphasize the need for targeted interventions to mitigate the environmental burden and contribute to sustainable hydrochar production.

In the present study, the ability for novel carbon microspheres (CMs) derived from date palm (Phoenix dactylifera) biomass using a hydrothermal carbonization (HTC) process and activated using phosphoric acid to remove methylene blue dye was investigated. Three types of palm-based wastes (seeds, leaflet, and inedible crystallized date palm molasses) were used and converted to CMs via the HTC process. The prepared samples were then activated using phosphoric acid via the incipient wetness impregnation method. The CMs samples before and after activation were analyzed using scanning electron microscopy (SEM), elemental analysis and scanning (CHNS), and the Fourier transform infrared (FTIR) and Brunauer–Emmet–Teller (BET) methods. The samples exhibited high BET surface areas after activation (1584 m²/g). The methylene blue adsorption results showed good fitting to the Langmuir, Fruendlich, and Temkin isotherm models for all activated samples. The maximum adsorption capacity achieved was 409.84 mg/g for activated CM obtained from the palm date molasses, indicating its high potential for application as a dye-based adsorption material.

This study investigates the extraction of cellulose from Saudi Arabia-based date palm biomass utilizing a natural deep eutectic solvent (NaDES) integrated with a microwave-assisted process. A comprehensive life cycle assessment (LCA) was conducted in accordance with the ISO 14040 standard, encompassing four key stages: goal and scope definition, life cycle inventory analysis (LCI), life cycle impact assessment (LCIA) and interpretation. The analysis was confined to a gate-to-gate boundary in which two impact assessment methods, namely, ReCiPe Midpoint (H) 2016 and ILCD 2011 Midpoint, were used to assess the environmental impacts. The OpenLCA software (version 2.1.1) with the European Life Cycle Database 3.2 (ELCD 3.2) was used in the study. The ReCiPe method identified impact categories such as fossil resource scarcity, terrestrial ecotoxicity, freshwater ecotoxicity, water consumption, human carcinogenic toxicity and marine ecotoxicity. Conversely, the ILCD method identified freshwater ecotoxicity, water resource depletion, mineral, fossil and resource depletion, human toxicity and cancer effects. The results indicate that freshwater ecotoxicity presents the most substantial environmental impact across both assessment methods, surpassing other categories. Fossil resource scarcity, even though originally appearing impactful, demonstrated a relatively lower normalized score compared to freshwater ecotoxicity. Terrestrial ecotoxicity and water consumption were found to be negligible in their impact. Our findings provide important insights into sustainable material science and waste management, affording potential applications for biomass utilization in the Gulf region.