Zero-valent iron nanoparticles (nZVI) enable the removal of pollutants from wastewater. However, for their safe use, it is necessary to determine the potential risk of nZVI remaining suspended in remediate water. Water samples from the WWTP effluent were remediated with different nZVI concentrations, at different mixing and settling times of iron particles. The results showed that laboratory-synthesized nZVIs were the most reactive among the tested nanoparticles. They removed PTE and pathogenic bacteria most effectively. However, the use of laboratory-synthesized nZVIs is limited, as they release B into the water, which originates from the reagents used in their synthesis. To some extent, all investigated nZVI species reduced nitrate and nitrite concentrations by conversion to ammonium cation. The additional formation of ammonium nitrogen was due to the interactions of nZVI with organic nitrogen present in the water from WWTP. At the optimal concentration of added nZVI in the form of Nanofer25 slurry, the optimal duration of mixing and settling, we achieved the most effective removal of PTE and disinfection of pathogens.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 32494887Immobilization is one of the most effective methods for remediation of contaminated soil and waste materials. In this case, reactive additives are mixed with the contaminated material, which leads to the formation of an inert composite. For the remediation study, we used the most polluted soil from the area of ??the old Cinkarna in Celje, sludge from wastewater treatment and other industrial waste. We investigated the efficacy of various additives (paper ash, ash, coal ash, steel slag, and red sludge from bauxite processing) as immobilization additives. Paper ash, coal fly ash and steel slag may contain hydraulic phases that allow chemical immobilization of contaminants. The red mud was not hydraulically active and was partially neutralized. The increase in immobilization efficiency in composites over time is associated with the formation of new minerals from hydration reactions and pozzolanic reactions. Adsorption is the main mechanism of red mud immobilization. Composites with paper ash, fly ash and red mud are environmentally acceptable in terms of inertness limits, and composites with slag have exceeded the Mo limit in aqueous effluent. All composites, except those with steel slag, are potentially useful as building materials for remediation of contaminated soils in degraded areas in the form of geotechnical embankments or embankments.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 2528615An important aspect of a construction-related circular economy is cascade recycling, where high value-added substances (eg critical raw materials) are recovered from waste before being recycled into secondary raw materials for construction. In this way, resources are used most rationally, and we provide a source of raw materials that are in short supply in Europe. This prevents substances that have no added value or even a negative effect on their useful properties (for example due to the introduction of potentially hazardous substances that pose a danger to the environment in the construction product in the event of its decomposition). We have developed a pilot device for recycling urine at the source before it is discharged into the sewer and to the treatment plant. The extracted components (phosphorus, nitrogen, potassium and other nutrients) can be used as a high-value fertilizer in agriculture. Municipal sludge, which is formed after the treatment of residual wastewater, can be a secondary raw material for construction with appropriate processing.
F.35 Other
COBISS.SI-ID: 15092483