Farmers’ Awareness in the Context of Climate Change: An Underutilized Way for Ensuring Sustainable Farmland Adaptation and Surface Water Quality

Use of Natural Sorbents in the Processes of Removing Biogenic Compounds from the Aquatic Environment

This paper presents the results of the evaluation of the possibility of using a selected sorbent of natural origin, mineral (opoka rock), for the removal of biogenic compounds from aqueous solutions. The analyzed opoka rock contains approximately 70% calcium carbonate (CaCO3) and from 26 to 27% silicon dioxide (SiO2) and has been classified as heavy opoka rock. The experiment focused on the sorption of organic components, including phosphorus (P), nitrogen (N) and carbon (C). It was carried out for two treatment systems, column tests and batch tests, for three samples of water—water from a water supply system, water from a fish pond and water from a garden pond—located in the region of Silesia (Poland). The results showed that the P removal efficiency was equal to 96.6% for the fine-grained sorbent (grain size <2 mm) and 90.8% for the coarse-grained sorbent (2–4 mm) in the batch tests, while lower effectiveness was observed for the column tests, reaching 67.8% and 54%, respectively. The efficiency of N (NH4+) removal was equal to 84% for both types of sorbents in the batch tests, while it was 47.7% for the fine-grained sorbent and 26.3% for the coarse-grained sorbent in the column tests. The efficiency of the removal of nitrate-nitrogen (NO3−) was higher for the fine-grained sorbent in all analyzed water samples. The use of materials of natural origin in industrial applications is a recommended direction, part of the green transition. The analyzed samples of opoka rock come from deposits, and opoka rock has so far not been analyzed in terms of its possible use in water and sewage treatment technology. Therefore, further research is recommended for this low-cost sorbent, which may be a competitive material for commercial products.

Floating Wetlands for Sustainable Drainage Wastewater Treatment

The preservation of water resources in modern urbanized society is a major concern. In this study, a floating constructed wetland (FWT) pilot plant was designed and constructed for the treatment of a polluted wastewater drain. A series of experiments were run continuously for a year in pilot-scale FWTs in a semi-arid area located in Egypt’s Delta. Four aquatic plant species (Eichhornia, Ceratophyllum, Pistia stratiotes, and Nymphaea lotus) were used to assess the performance of FWTs for pollutant removals, such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), electrical conductivity (EC), and total dissolved solids (TDS), from drainage wastewater to reuse the treated effluent in irrigation practices. The FWT systems were fed drainage tainted water on a weekly basis, and the concentrations and removal efficiency were assessed in the experiments. The average reduction in BOD, COD, TSS, TDS, TN, EC, and TP were 76–86%, 61–80%, 87–95%, 36.6–44.1%, 70–97%, 37–44%, and 83–96%, respectively. ANOVA with Post-HOC t-tests show that the Eichhornia, Pistia stratiotes, and Nymphaea lotus have the highest BOD and COD removal performance, whereas Pistia stratiotes and Nymphaea lotus have the highest TN and TP removal performance. In all cases, the Nymphaea lotus performed well in terms of pollutant removal. In addition, a design procedure for a FWT systems is presented. For wastewater treatment, FWT systems have proven to be a low-cost, long-term option.