The potential of livestock slurry as a secondary raw material lies in its macronutrient content—nitrogen, phosphorus, and potassium. To realize its value as high-quality fertilizer, efficient separation and concentration methods must be employed. This work examined the liquid pig slurry fraction, focusing on nutrient recovery and its potential use as fertilizer. Indicators were used to evaluate the performance of the proposed technological train, situated within the context of a circular economy. The solubility of ammonium and potassium species across the entire pH range prompted a study of phosphate speciation from pH 4 to 8 to increase macronutrient recovery from the slurry, resulting in two distinct treatment trains adapted for acidic and alkaline pH conditions respectively. The application of an acidic treatment system incorporating centrifugation, microfiltration, and forward osmosis produced a liquid organic fertilizer containing 13 percent nitrogen, 13 percent phosphorus pentoxide, and 15 percent potassium oxide. Through the alkaline valorisation process, centrifugation combined with stripping by membrane contactors produced an organic solid fertilizer (77% N, 80% P2O5, 23% K2O), an ammonium sulphate solution (14% N), and irrigation water. Acidic treatment demonstrated a recovery of 458 percent of the initial water content and less than 50 percent of the contained nutrients—283 percent nitrogen, 435 percent phosphorus pentoxide, and 466 percent potassium oxide—in terms of circularity metrics, resulting in a fertilizer yield of 6868 grams per kilogram of treated slurry. 751% water recovery was achieved for irrigation, coupled with substantial increases in nutrients (806% nitrogen, 999% phosphorus pentoxide, 834% potassium oxide) during the alkaline treatment process. This equates to 21960 grams of fertilizer yield per kilogram of treated slurry. Treatment paths in acidic and alkaline conditions show promising results for nutrient recovery and valorization. The products obtained, namely a nutrient-rich organic fertilizer, a solid soil amendment, and an ammonium sulfate solution, are in line with the European regulations for fertilizer application in agricultural fields.
The continuous expansion of global urbanization has significantly increased the spread of emerging pollutants, encompassing pharmaceuticals, personal care products, pesticides, and micro- and nano-plastics, within aquatic environments. Low concentrations of these contaminants are still harmful to the delicate nature of aquatic ecosystems. To better ascertain the influence of CECs on aquatic ecosystems, it is imperative to quantify the concentration levels of these pollutants within these systems. The present monitoring of CECs demonstrates a lack of equilibrium, overemphasizing certain categories and creating a void of data concerning environmental concentrations in other CEC types. Citizen science is a potential methodology for augmenting the monitoring of CEC and establishing their levels within the environment. While citizen input in the observation of CECs is a positive step, it is accompanied by certain hurdles and questions. We survey the literature on citizen science and community science projects to understand their approaches to monitoring various groups of CECs in freshwater and marine environments. We also recognize the merits and shortcomings of citizen science in the context of CEC monitoring, providing direction for sampling and analytical strategies. The implementation of citizen science shows variations in monitoring frequency among different CEC groups, according to our results. Evidently, volunteer involvement in microplastic monitoring surpasses the involvement in pharmaceutical, pesticide, and personal care product monitoring programs. Yet, these variances do not inevitably indicate a reduced selection of sampling and analytical approaches. To conclude, our roadmap demonstrates which strategies can be employed to strengthen the monitoring of all CEC populations through citizen science.
The bio-sulfate reduction process within mine wastewater treatment results in sulfur-laden wastewater, characterized by the presence of sulfides (HS⁻ and S²⁻) and metallic elements. In such wastewater, sulfur-oxidizing bacteria generate biosulfur, which usually presents as negatively charged hydrocolloidal particles. AZD1480 order Recovery of biosulfur and metal resources faces significant obstacles when relying on traditional methods. This research focused on the sulfide biological oxidation-alkali flocculation (SBO-AF) approach for extracting the mentioned resources from mine wastewater, offering a valuable reference for pollution control and resource recovery in the mining industry. In-depth investigation into SBO's biosulfur synthesis and the influencing parameters of SBO-AF was concluded by its implementation in a pilot-scale wastewater process to reclaim resources. The study's findings show that partial sulfide oxidation was achievable with a sulfide loading rate of 508,039 kg/m³d, dissolved oxygen levels of 29-35 mg/L and a temperature range of 27-30°C. Precipitation of metal hydroxide and biosulfur colloids occurred concurrently at pH 10, a consequence of the interactive effect of precipitation capture and adsorption-based charge neutralization. Pre-treatment wastewater exhibited manganese, magnesium, and aluminum concentrations of 5393 mg/L, 52297 mg/L, and 3420 mg/L, and a turbidity of 505 NTU; subsequent treatment lowered these figures to 049 mg/L, 8065 mg/L, 100 mg/L, and 2333 NTU, respectively. Plant cell biology Sulfur and metal hydroxides were the principal substances found in the recovered precipitate. The measured average percentages for sulfur, manganese, magnesium, and aluminum were 456%, 295%, 151%, and 65%, respectively. An analysis of economic viability, coupled with the aforementioned results, demonstrates SBO-AF's clear technical and economic superiority in recovering resources from mine wastewater.
Water storage and flexibility are key benefits of hydropower, the leading renewable energy source globally; however, this significant source also poses considerable environmental repercussions. The attainment of Green Deal goals necessitates a balancing act in sustainable hydropower, harmonizing electricity generation with its impact on ecosystems and societal advantages. To effectively manage the tensions between green and digital advancements, the European Union (EU) is increasingly relying on the implementation of digital, information, communication, and control (DICC) technologies. This study presents how DICC fosters the ecological integration of hydropower into Earth's various spheres, emphasizing the hydrosphere (water quality/quantity, hydropeaking control, flow regimes), biosphere (riparian health, fish habitats, migration routes), atmosphere (methane emissions and reservoir evaporation), lithosphere (sediment transport, reducing seepages), and anthroposphere (combined sewer overflow pollution, chemical waste, plastic/microplastic contamination). A discussion of the core DICC applications, exemplary case studies, encountered impediments, Technology Readiness Level (TRL), benefits, constraints, and their interconnectivity with energy generation and predictive operation and maintenance (O&M) is presented, pertaining to the mentioned Earth spheres. The European Union's top concerns are brought into sharp focus. Although the paper primarily concentrates on hydropower, the same considerations hold for any artificial barrier, water reservoir, or constructed structure influencing freshwater ecological systems.
In recent years, a significant rise in cyanobacterial blooms has occurred worldwide, directly attributable to global warming and water eutrophication. This has resulted in a variety of water quality issues, with the noticeable odor problem plaguing lakes attracting substantial attention. Toward the conclusion of the bloom, a copious amount of algae amassed on the top layer of sediment, potentially resulting in odor pollution in the lakes. vitamin biosynthesis Lakes frequently exhibit a perceptible odor, largely due to the presence of the algae-derived compound, cyclocitral. This study examined the impact of abiotic and biotic factors on -cyclocitral concentrations in water by conducting an annual survey of 13 eutrophic lakes in the Taihu Lake basin. The sediment's pore water (pore,cyclocitral) showed a pronounced enrichment of -cyclocitral, exhibiting an average concentration approximately 10,037 times that of the water column. Structural equation modeling suggests a direct relationship between algal biomass and pore-water cyclocitral levels with the concentration of -cyclocitral in the water column. The presence of total phosphorus (TP) and temperature (Temp) fostered algal biomass growth, which further increased the generation of -cyclocitral in both the water column and pore water. A noteworthy observation was that, with Chla at 30 g/L, algae exerted a significantly enhanced effect on pore-cyclocitral, which played a crucial role in modulating -cyclocitral levels throughout the water column. Through a systematic study, we gained a profound understanding of the interplay between algae, odorants, and regulatory processes in aquatic ecosystems. This comprehensive analysis uncovered the crucial role of sediments in producing -cyclocitral in eutrophic lake water, which is vital for a more accurate understanding of off-flavor development and future lake odor management.
Coastal tidal wetlands' essential contributions to flood protection and biological preservation are fairly and properly acknowledged. Quantifying the quality of mangrove habitats hinges on the dependable measurement and estimation of topographic data. This research presents a novel method for swiftly constructing a digital elevation model (DEM) that incorporates instantaneous waterlines and tidal level data. Employing unmanned aerial vehicles (UAVs), on-site analysis of waterline characteristics became possible. Object-based image analysis, as shown in the results, demonstrates the greatest accuracy in waterline recognition, while image enhancement improves the overall accuracy.