Numerous firms dealing with widely understood natural environment protection offer various solutions for domestic sewage treatment plants. While choosing the suitable variant of such installation, an investor is driven in the first place by economic factors, easy operation and high operational reliability. The article presents and assesses four domestic sewage treatment systems working on the basis of activated sludge technology, biofilter and combinations of these two methods, selected in view of the results they achieved. Because of the specific character of sewage produced in the areas with dispersed buildings, sewage treatment plant installations must prove highly reliable under variable operating conditions, they should be cheap to construct and utilize and not require complicated service. It seems that Sequencing Batch Rectors (SBR) treatment plants meet these requirements, as well as combined installations which join a classic activated sludge method and submerged or mobile biofilter systems. In case of SBR reactors, the whole process of sewage treatment occurs in a single tank where individual phases of the working cycle are controlled by computer. Regulation of supplied air quantity allows to modify the bioreactor work cycle in the way making possible additional reduction of biogenic compounds from sewage. Technical solutions which combine activated ...
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 possibility of biological treatment of sewage from the production of organic polymers was assessed. The chemical quality of raw and treated sewage (CODCr, BOD5, ammonia nitrogen, nitrate nitrogen, total suspension, pH, chlorides and sulfates) was analyzed. The level of reduction in the analysed sewage quality indicators (%), sewage biodegradability (α) and the technical efficiency of treatment (Psw) were determined. It was shown that the limited effectiveness of the treatment process results from the excessively high load of organic contaminants. The analysed sewage contains substances which do not biodegrade easily, negatively influencing the conditions for activated sludge processes in the bioreactor. The activated sludge is characterized by low biodiversity and has an insufficient structure. The treatment process requires an introduction of technological changes which will lead to a decrease in the load of sewage entering the bioreactor. ...
