Investigations with wastewater from small abattoir were carried on hybrid constructed wetland systems. Mean COD of wastewater reached 3000 gO2∙m-3 and concentration of Ntot was about 400 g∙m-3. The main problem was sufficient removal of NO3-N and Ntot. In order to intensify denitrification, a part of effluent from the vertical bed was recirculated to the settling tank. Effectiveness of Ntot removal on the plant raised along with the rise of recirculation level and obtained for 100, 150 and 200 % respectively 85,7; 91,9 and 96,6 %. The main contamination of wastewater from small fruit-and- vegetable processing plant consist of organic substance (to 10000 gO2∙m-3 as COD). The bed with vertical flow built of various fractions of sand and with fully developped reeds was found very effective in its removal. Sufficient results were obtained with loading of the bed up to 90gCOD∙m-2∙d-1. ...
Biological methods have always played an important role in sludge treatment technology. Biological treatment may be conducted in various ways, in many cases as activated sludge method. Currently the processes and factors affecting efficient elimination of pollutants from municipal wastes have been relatively well identified. On the other hand the situation is different for industrial sludges. Efficiency of industrial sludge treatment plant depends mainly on physicochemical properties of sludge inflowing from individual enterprises. The work aimed at identification of sugar industry waste composition in view of its susceptibility to the processes of biological treatment, mainly removal of nitrogen compounds. The subject research was conducted in a laboratory model of bioreactor composed of an anoxic chamber where the denitrification process was conducted and aerated tank with a built-in secondary settlement tank in which nitrification process was taking place. Analyzed were sugar-mill wastes supplied from a factory and sewage treated in the analyzed model. Conditions in both chambers of the model treatment plant were monitored during the investigations. Activity of the activated sludge and the course of nitrification and denitrification processes were determined using OUR, AUR and NUR tests. The analyses have revealed that sugar wastes composition is variable in time and ...
Industrial effluents have currently constituted the main portion of a total volume of generated sewage, however a tendency to diminish their quantity has been observed. Treatment of specific sewage faces serious technological problems due to the special character of production in the manufacturing plants, which affects the irregularity and amount of pollutants. Considerable quantitative and qualitative variability of the generated sewage is perceivable even at the plants with the same profile of production. Therefore, it is necessary to identify precisely the properties of effluents produced not only by the same branches of industry but even by single factories. Considering the food sector enterprises, the least amount of literature data is available on physicochemical properties of effluents generated by confectionery industry. Therefore, the study aims to characterize the effluents produced by confectionery factories and compare them with the properties of sewage from other food manufacturing plants. The main emphasis was put on the analysis of the results of research on confectionery effluent treatment in a model bioreactor with activated sludge. The main characteristics of sewage generated by confectionery factories are considerable fluctuations of pollutant quantities, which is a frequent cause of observed operational problems with the treatment plant process line. Compared ...
The paper presents analysis of modernization possibilities of the techno-logical chain in the sewage treatment plant in Lopuszna concerning removal of biogenic pollutants. High operation effectiveness of the analyzed treatment plant is important regarding the protection of water in the cascade of Czorsztyn-Niedzica-Sromowce Wyzne reservoirs against the excessive pollution. The assess-ment of modernization possibilities of the treatment plant was based on the num-ber of computer simulations upon the ASIM2d model. This model includes 21 separate processes, which were divided into: hydrolysis processes, processes with heterotrophic bacteria XH, processes with poliphosphates' accumulating bacteria XPAO, processes with nitrifiers XAUT and chemical processes.The analysis revealed that low effectiveness of biogenic substance removal in the objective treatment plant results from the lack of activated sludge recircula-tion into the anaerobic chamber which causes that the biological dephosphatation process is not sufficient enough. The situation will change if the internal and external recirculation chain is corrected and the anaerobic chamber is included in the technological chain of the objective sewage treatment plant. ...
The research aimed to learn if and to what extent extraneous waters, occasionally flowing into sanitary sewer system during atmospheric precipitation, change proportions of selected pollution indices which are significant regarding biological sewage treatment. The following proportions between pollution indices should be maintained in the sewage subjected to biological treatment process: COD:BOD5 ≤ 1.8; BOD5:N ≥ 4.0, BOD5:P ≥ 25; COD:P ≥ 3.6. Investigations conducted in two sewer systems located in the Małopolskie voivodeship revealed that extraneous waters infiltrating the intercepting sewers during wet weather negatively affect all proportions between pollution indices. Increasing amount of extraneous waters in sewer systems caused the greatest changes of BOD5:N and BOD5:P proportions. On the basis of conducted research it was found that considerable quantities of nitrogen and phosphorus compounds are supplied to the sewer system with extraneous waters, which in biological denitrification and dephosphatation processes may lead to a deficit of organic compounds causing a necessity to provide an external source of carbon for the reactor chambers, such as methanol, ethanol, acetic acid, glucose or others. During the conducted investigations it was demonstrated that extraneous waters in interceptors cause not only sewage dilution, but also significantly change its chemical composition. ...
