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EN
The rapidly changing quality of irrigation water requires urgent attention to understand and predict the long-term effects on soils and food crops, especially in a situation of global freshwater scarcity. The aim of the research was to assess changes in water quality in two selected lakes located in Poland in 2009–2016. The study was carried out in terms of the possibility of using selected reservoirs as sources of water for sprinkler irrigation of agricultural crops. The presented analysis was compared with a similar one carried out in 1999–2006 and 2004–2009 to determine the historic and present water quality state. Results indicate, that the source of pollution of the lakes is most often outflows from sewerage systems, the precipitation and surface runoff from the catchment areas of these lakes, which are mainly used as agricultural land. In Lake Niepruszewskie, the oxygen conditions, water transparency, phosphorus content, sestone dry matter and coliform titre increased, while the biological oxygen demand (BOD5), nitrogen, and chlorophyll content decreased. According to present research, in the Strykowskie Lake, the phosphorus content and BOD5 decreased, while the sanitary condition, nitrogen content and oxygen conditions deteriorated. The reduction of mineral fertilization in recent years has reduced the degradation of the lakes and allowed the water quality to remain in Class III of purity. Despite the visible improvement in the general condition of both studied lakes, constant monitoring of their quality is necessary, which is obligatory for the water from these reservoirs to be used for sprinkler irrigation of crops.
EN
Membrane bioreactor (MBR) is stable and rising wastewater treatment reactor though membrane fouling and energy expenditure remain operational impediments and challenges for the wider deployment of the MBR technology. The majority of municipal wastewater contains low quantities of suspended, dissolved inorganic and organic particles. Proteins, carbohydrates, synthetic detergents, lignin, soaps, lipids and their decomposition products, along with many natural and synthetic organic chemicals from industrial processes, are also examples of impurities present in water. In addition, municipal wastewater contains a variety of inorganic chemicals, such as heavy metals, which might have phytotoxic and health consequences, limiting its usage in agriculture. In this study, an electrochemical membrane bioreactor (EMBR) has been developed to reduce several impurities from real municipal wastewater; moreover bioelectricity was also generated simultaneously. The maximum removal of biological oxygen demand (BOD), chemical oxygen demand (COD) and total dissolved solid (TDS) were 35.57%, 31.55%, and 32.84 %, respectively, after a 5-day experimental run.
EN
Biological treatment in wastewater treatment plants appears to be one of the most crucial factors in water quality management and planning. Though, measuring this important factor is challenging, and obtaining reliable results requires signifi cant eff ort. However, the use of artifi cial neural network (ANN) modeling can help to more reliably and cost-effectively monitor the pollutant characteristics of wastewater treatment plants and regulate the processing of these pollutants. To create an artifi cial neural network model, a study of the Samsun Eastern Advanced Biological WWTP was carried out. It provides a laboratory simulation and prediction option for flexible treatment process simulations. The models were created to forecast influent features that would affect effluent quality metrics. For ANN models, the correlation coefficients R-TRAINING and R-ALL are more than 0.8080. The MSE, RMSE, and MAPE were less than 0.8704. The model’s results showed compliance with the permitted wastewater quality standards set forth in the Turkish water pollution control law for the environment where the treated wastewater is discharged. This is a useful tool for plant management to enhance the quality of the treatment while enhancing the facility’s dependability and efficiency.
EN
This study shows the results of long-term inland water monitoring using Sentinel-2 data for Głuszyńskie Lake in the years 2015–2022. Four water quality parameters: biological oxygen demand (BOD), dissolved organic carbon (DOC), chlorophyll concentration (CHL) and electrical conductivity (EC) were calculated according to formulas found in the literature. The results were validated based on measurements conducted in 2021 and 2022, where for BOD, DOC and CHL high determination coefficients (0.77 and 0.79) were observed, and the EC determination coefficient was equal to 0.45. The results show that empirical formulas can be used for qualitative analyses of inland water quality, while for quantitative analyses more extensive field work needs to be performed.
EN
Organic compounds are the most diverse group of contaminants. The largest anthropogenic source of these contaminants in water is municipal and industrial wastewater. One of the indicators of surface water pollution is biological oxygen demand (BOD). Purifying water from organic micropollutants is a serious challenge and requires the development of newer and more effective methods. The removal of such contaminants is most effective only in advanced oxidation processes (AOP), which include UV photolysis and photocatalysis. The presented results are from preliminary research to evaluate the effectiveness of water treatment by ultraviolet (UV) photolysis and photocatalysis. Treatment efficiency was evaluated on the basis of changes in the BOD index before and after the advanced oxidation process of raw water. The values of the BOD5 index determined in accordance with PN-EN 25813:1997. The exposure time of the samples was a maximum of 60 minutes. The tested material was water samples taken from the Rudawa River, which is one of the drinking water sources for Krakow. The initial BOD5 value (expressed as concentration of O2) for all samples was about 8 mg/L but it has decreased to over 2 mg/L due to AOP processes. This means that after an hour, more than 75% of organic compounds present in the raw water were removed. For photocatalysis (TiO2-MMT), the exposure time of the samples was a maximum of 35 minutes. Water samples taken from the Rudawa River were also used as test material. The initial BOD5 value for all samples was about 9 mg/L but it has decreased to about 4 mg/L due to the photocatalysis process. This means that after 35 minutes, 55% of the organic compounds present in the raw water were removed.
EN
The research was carried out because of a survey of wastewater treatment plant of a chemical factory, which is planned to receive the dimethylamine-containing wastewater flow. It was essential to investigate the influence of dimethylamine and removal on organiс pollutants and nitrogen compounds as well as to determine the limiting concentration of dimethylamine. There were variable concentrations of dimethylamine (20–500 mg/L) under investigation in several simultaneous laboratory benches. The results showed that the dimethylamine concentration lower than 40 mg/L showed almost no impact on wastewater treatment; meanwhile, the growth of concentration up to 300 mg/L (and above) dropped the treatment efficiency by times.
EN
Wastewater from the confectionery industry is characterized by daily and seasonal variability of composition and quantity which adversely affects the process of their disposal. Confectionery plants discharge about 300-500 m3 per month of technological wastewater. Sewage from the confectionery industry belongs to biologically degradable. It is characterized by high values of chemical oxygen demand (COD) and biological oxygen demand (BOD). The article reviews various methods used to treat wastewater from the confectionery industry. Attention was paid to the applicability of a particular method, its advantages and disadvantages and the costs of implementation. The technology of industrial wastewater treatment uses both mechanical and physicochemical methods as well as biological ones. Techniques of sewage treatment usually consist of several stages which use different processes. Low-cost materials such as natural minerals, agricultural waste, industrial waste, biosorbents, and others contribute to the improvement of aerobic sewage conditions. The main weakness of typical sewage treatment plants is their large area, high investment, and exploitation costs. Therefore, a good solution may be the use of the membrane biological reactor which combines the classical technique of activated sludge and filtration on micro-filtering membranes.
8
Content available remote Analysis of chosen models describing the changes in BOD5 in sewages
EN
The paper presents a comparative analysis of five models describing the changes in BOD5 based on results of the experimental research. The model of Thomas (1950), Navone (1960), Fujimoto (1964), Adrian and Sanders (1992-1993) as well as Young and Clark (1965) used by Adrian and Sanders (1998) were studied. The values of BOD5 were measured for 5 days with the measurement step of 3 h in every sample out of 92. Therefore, each course of the variation was described by 40 measurement points. To define the influence of the processes of nitrification on the level of BOD5, each sample was examined with addition of an inhibitor of nitrification and without it. It was found that reaction constant did not depend on the final value of BOD in the models of the firstt order (Thomas, Navone and Fujimoto) contrary to the models of the second order (Young and Clark), and especially the half order (Adrian and Sanders). It is the easiest to define the lag phase of the time dependence BOD by the model of Thomas, which clearly depicts the border between the growth sequence of BOD and the initial fluctuations of the growth. The influence of the nitrification inhibitor on the course of the BOD was not noticed in all samples. It suggests that the process of nitrification occurred in a part of the samples almost from the first day and more often from the second or third day and in others this process did not occur in the whole measurement period (5 days) at all.
EN
Saprobiological investigation using plankton is a part of everyday monitoring practice for determination of water quality in Hungary. However there is an important question: Is this way of using plankton (mainly phytoplankton) good enough and bringing enough information? We can hear, this method is too old and its result are not collateral with different chemical way’s describing saprobity. Another problem of this biological method is being so laborintensive, demanding a well qualified knowledge on algology and protozoology. To solve these problems and questions we examined saprobiological and the chemical results, describing water quality of tributaries of Hungarian Upper-Tisa, in years 2001-2002. Summarizing results of our investigations, we can say: biological (saprobiological) method of analyses for saprobity is not worse than chemical ways and can give us more information about ecological parameters.
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