Eniko Gaspar

This study investigates the influence of interannual climate variability on wheat quality during long-term storage under identical technological conditions. The same wheat cultivar was stored during two consecutive periods (2023–2024 and 2024–2025) in a flat warehouse without mechanical aeration or forced cooling, while environmental parameters (temperature and relative humidity) and quality indicators (grain moisture content, test weight, gluten content, and protein content) were continuously monitored. Based on the experimental data, empirical predictive models describing the relationships between storage time, environmental conditions, and wheat quality indicators were developed using nonlinear regression and curve-fitting techniques implemented in TableCurve 3D. Two model categories were established: a transfer model for moisture and temperature evolution and a degradation model for test weight, gluten, and protein changes. The models showed good predictive performance, with coefficients of determination ranging from R² = 0.82 to 0.97. Model performance was assessed using residual analysis and statistical performance indicators, yielding low prediction errors and high Nash–Sutcliffe efficiency coefficients (0.95–0.99). The 2024–2025 period exhibited slightly greater thermal variability, with atmospheric thermal amplitude increasing from approximately 33 °C to 34 °C and grain thermal amplitude increasing from approximately 30 °C to 32 °C compared with the 2023–2024 storage period. This was accompanied by differences in moisture evolution patterns and more pronounced reductions in test weight, gluten, and protein content. These findings suggest that climate variability is associated with changes in hygrothermal conditions and wheat quality deterioration processes, while the proposed models provide reliable tools for predicting quality evolution and supporting adaptive grain storage management under changing climatic conditions.

In the current global context of the natural resource crisis and the need for environmental protection, sustainable economy strategies are becoming imperative. These strategies aim to optimize wastewater treatment processes, with a particular focus on the removal of biological and chemical quality indicators such as BOD, COD and TSS. By developing and implementing advanced technologies and effective resource management methods, this article explores ways the industry can reduce its negative environmental impact and contribute to a sustainable future. The proposed research investigates the impact of 40% ferric chloride on the purification processes of domestic wastewater using biological contactors. The study evaluates the efficiency of pollutant removal through measurements such as biochemical oxygen demand over 5 days (BOD), chemical oxygen demand (COD) and total suspended solids (TSS). Through the statistical analysis of the obtained results, the research identifies opportunities for innovative strategies in the sustainable economy, thus contributing to the optimization of purification process efficiency and significantly reducing pollution’s impact on the environment. In conclusion, this research highlights the use of 40% ferric chloride as an effective and sustainable method to improve the efficiency of wastewater treatment processes, focusing on BOD, COD and TSS removal. The findings demonstrate significant pollutant reduction and environmental impact mitigation, underlining its potential for Sustainable Development Goals. The study supports innovative strategies for optimizing water quality and recommends further evaluation of long-term impacts on human and environmental health.

In the context of ever-increasing water demand and pressures on natural resources, efficient water management is becoming a major priority for contemporary society. Since nitrogen and phosphorus, as essential nutrients, play a crucial role in the dynamics of aquatic ecosystems, but excessive concentrations can cause eutrophication of receptors, they need to be eliminated as completely as possible while respecting the principles of a sustainable economy, efficiency, and quality. In this study, the efficiency of optimizing the technological process of wastewater treatment by dosing FeCl₃ 40% solution to reduce nitrogen and phosphorus concentrations in treated water was investigated. The results obtained revealed that the use of this type of flocculant resulted in an increase in the efficiency of the removal process of total N by an average of 35.57 mg/L and total P by an average of 3.89 mg/L. Also, the results, which are interpreted by mathematical modeling, show that the optimal use of FeCl₃ 40% solution leads to a significant reduction in pollutants, well below the maximum permitted values (according to Romanian regulations, the maximum value for total phosphorus is 2 mg/L and total nitrogen is 15 mg/L for localities with a population between 10,000 and 100,000 inhabitants). This technical approach not only improves the quality of treated water but also contributes to minimizing the impact on aquatic ecosystems and promotes the principles of circular economy in water resource management. By optimizing the dosage of FeCl₃ 40% solution in the treatment process, the efficiency of the coagulation and flocculation processes is maximized, thus providing a viable and sustainable solution for reducing the environmental impact of nitrogen and phosphorus and promoting responsible and sustainable water resource management.

The wastewater treatment plant of Agnita, Romania was designed with a rotational biological contactor system for a population of approximately 9500, but for environmental protection reasons it must comply with regulations concerning nitrogen and phosphorus designed for larger communities. In order to achieve the prescribed limits for these pollutants, we have used a 40% FeCl₃ solution, continuously added to the distributor, without changes in flow or equipment. Its use boosts the removal of ammonia nitrogen, and phosphorus, bringing them within the limits and with reasonable cost. To determine the ferric chloride to be used we considered, aside from the pollutant load, the water temperature, and introduced a new parameter: specific removal power that enabled us to optimize the volume of FeCl₃. A major contribution to nitrogen removal was achieved by the denitrification bacteria favored by the presence of ferric ions, which also precipitate phosphorus. The results of this study, performed since September 2021, enable us to continue to use this method and enlarge its application to other plants owned by the local operator.