Filters
The Relationship between Mortality from Cardiovascular Diseases and Total Drinking Water Hardness: Systematic Review with Meta-Analysis
Background: Interest in water chemical activity, its content, and its impact on human health has greatly increased throughout the last decade. Some studies suggest that drinking water with high hardness may have preventative effects on cardiovascular diseases. This study aims to investigate the association between drinking water hardness and cardiovascular disease (CVD) mortality. Methods: The study selection process was designed to find the association between drinking water hardness and CVDs mortality. The search included both qualitative and quantitative research and was performed in three databases: Web of Science (Clarivate Analytics, Ann Arbor, MI, USA), PubMed (National Institute of Health, Bethesda, MA, USA), and Scopus (Elsevier, RELX Group plc, London, UK). The project was registered in the International Prospective Register of Systematic Reviews (PROSPERO), registration number: CRD42020213102. Results: Seventeen studies out of a total of twenty-five studies qualitatively analyzed indicated a significant relation between total water hardness and protection from CVD mortality. The quantitative analysis concluded that high drinking water hardness has a significantly lowering effect on mortality from CVDs, however, the heterogeneity was high. Conclusions: This systematic literature review shows that total water hardness could affect CVD prevention and mortality. Due to the many confounding factors in the studies, more research is needed.
Recent Issues and Challenges in the Study of Inland Waters
This paper addresses several important problems and methods related to studies of inland waters based on the existing scientific literature. The use of UAVs in freshwater monitoring is described, including recent contact and non-contact solutions. Due to a decline in biological diversity in many parts of the globe, the main threats are described together with a modern method for algae and cyanobacteria monitoring utilizing chlorophyll a fluorescence. Observed disturbances in the functioning of river biocenoses related to mine waters’ discharge, causing changes in the physico-chemical parameters of waters and sediments, give rise to the need to develop more accurate methods for the assessment of this phenomenon. Important problems occurring in the context of microplastic detection, including the lack of unification, standardization and repeatability of the methods used, were described. In conclusion, accurate results in the monitoring of water quality parameters of inland waters can be achieved by combining modern methods and using non-contact solutions.
The Efficiency of a Biological Reactor in a Domestic Wastewater Treatment Plant Operating Based on ABS (Acrylonitrile Butadiene Styrene) Material and Recycled PUR (Polyurethane) Foam
The primary objective of this research was to assess the efficacy of a novel solution under conditions closely resembling those of real-world scenarios. Biological beds, or filters, hold significant potential for widespread implementation in individual households, particularly in areas with dispersed housing. The system’s aim was to improve the quality of wastewater treated in on-site domestic biological treatment plants. A pivotal aspect of the project involved developing a prototype research installation for conducting comprehensive testing. Our installation system consisted of several components designed to create a laboratory-scale model for domestic wastewater treatment. The model comprised four biological reactors filled with ABS material and secured by a PUR frame. Additionally, the tested model included a controller for wastewater dosing control, a septic tank as a reservoir, and four tanks for collecting purified wastewater. Through regression analysis using the Generalized Linear Model (GLM), a correlation between CODCr and TSS was revealed. This study presents the research findings concerning the development of a prototype installation that incorporates an advanced reactor or filter. The data derived from this research have the potential to contribute to the creation of products that enhance the performance and efficiency of household wastewater treatment systems.
Evaluation of the possibility to use wood-polymer composites for treatment of wastewater from the septic tank
The impact of grey water on yield and aesthetic properties of perennial ryegrass
Selecting optimal turf varieties is crucial for the sustainable management of urban green areas. This study focused on enhancing the overall quality and resilience of urban, suburban, and peri-urban areas. It aimed to assess the aesthetic acceptability of perennial ryegrass turf irrigated with greywater. Sand pots containing perennial ryegrass were irrigated with semi-natural greywater and tap water at two irrigation levels of 15 and 30 mm∙week−1 to examine their effects on aesthetic properties. The experiment included two variations: with and without fertilisation. The study objectives were evaluated using a visual aesthetic scale and by measuring the total dry and wet mass yield of ryegrass. While the aesthetic properties of the grass were found to be relatively low, they were deemed acceptable. The presence of fertilisation had significant impacts on both aesthetic properties and biomass yield. The experiment demonstrated that perennial ryegrass can be cultivated effectively at relatively low irrigation levels, even in soil lacking an organic fraction. The results indicate the possibility of maintaining this type of vegetation in the form of green roofs and vegetative swells. In the case of sandy soil lawns, their purpose should not include intensive trampling due to relatively poor rooting and low soil stability. These findings underscore the potential for sustainable landscaping practices that incorporate greywater irrigation and highlight the importance of considering various factors to optimise aesthetic appeal and productivity of green spaces.
Nitrogen compounds in effluents from a septic tank
The paper presents the results of long-term studies on the concentrations of total nitrogen and ammonium nitrogen in a septic tank effluent. A statistical analysis concerning the sampling day and the season was performed. The mean concentration of total nitrogen in the effluent was 47±9 g N/m3 and the mean concentration of ammonium nitrogen was 33±11 g N/m3. Results on the cumulative distributions of total nitrogen and ammonium nitrogen in the outflow from the septic tank have also been presented.
Use of Shredded Recycled Plastic as Filter Bed Packing in a Vertical Flow Filter for Onsite Wastewater Treatment Plants: Preliminary Findings
Household wastewater is a problem, especially in areas with a dispersed settlement where there is no wastewater collection system or wastewater treatment plant. In this case, it is necessary to build a local or onsite wastewater treatment plant. This paper is an attempt to analyse the possibility of using recycled shredded ABS plastic (acrylonitrile butadiene styrene) as packing media in an experimental vertical flow filter for use in on-site wastewater treatment plants. Studies have shown that shredded recycled ABS is a promising filtration material that has several features important in the treatment process, like a large surface area, high mechanical strength and chemical inertness. The system was operated with a hydraulic load of 50 dm3/m2 (3 months). BOD5 (biochemical oxygen demand), COD (chemical oxygen demand), and total suspended solids (TSS) reduction efficiency in the primary effluent was high; 94.4%, 77.8%, and 92.8%, respectively.
The Influence of Fibers from Domestic Laundry Wastewater on the Clogging Process of a Filter
This study presents the impact of the size and shape of particles in laundry wastewater on the clogging process of a porous material. Clogging can be defined as a mechanical limitation of flow through porous media. The process of mechanical clogging was investigated in this study. The research was conducted in laboratory conditions in a filter column filled with glass beads whose diameter corresponded to coarse sand. The results reveal the influence of graywater quality on filter hydraulic conductivity and bed clogging, showing the impact of fiber particles in wastewater (sewage from home laundry) on the clogging process in soil. The results confirm that fiber particles significantly reduce filter permeability, particularly due to the formation of a filter cake. As analyzed in this paper, the distribution of quantitative data on particles of different sizes found in laundry wastewater indicates that they mainly accumulate in the upper layer, where particles with fiber lengths ranging from 0 to 1600 µm can be found. The average length of the fibers decreased with increasing depth. At a depth of approximately 10 cm, fibers with dimensions in the range of 0 to 100 μm were predominantly observed.