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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Vliv odtoku z čistíren odpadních vod na krasové toky / Effect of effluent from wastewater treatment plants on karst rivers

Schrimpelová, Kateřina January 2015 (has links)
Karst rivers are special type of rivers because of their hydrography conditions. They usually flow from non-karst area and as soon as they reach in to the karst area they disappear underground. There, they flow through cavities until they reach the surface again. The aim of this thesis is to assess the impact of water outflow from wastewater treatment plant on karst rivers. The study was done in the central area of CHKO Moravský kras where the impact of two WWTP on a cave system Rudické propadání – Býčí skála is evaluated. As a part of this study a half-year monitoring was carried out, which consisted of water sampling once every two weeks. In total, 13 water samples were taken from 8 sampling points. Also 4 additional one-time samples were taken from the cave system. Moreover, flow rate, temperature, conductivity, oxygen concentration and pH were measured at the sampling point. Afterwards, the content of undissolved solids, CODCr, BOD, N-NH4+, N-NO2-, N-NO3-, P-PO43- and total phosphorus were determined in the samples. The change of parameters in time and during the flow in the river was observed from the measured values. The balance of pollutants in particular parts of the river was calculated. The outflow values from waste water treatment plants were compared to the emission limits for surface waters and the parameters of rivers were compared to the environmental quality standards. According to the results, it can be observed that the water quality improves after passing through the cavities. It was proven that the outflows from the observed waste water treatment plants are negatively influencing the water streams. The most serious problem is the wash up of sludge from WWTP Rudice and its consequent sedimentation in the river and/or outflow to the Rudické propadání.
112

Návrh experimentální solární sušárny / Pilot Scale Solar Dryer Design

Plucar, Tomáš January 2011 (has links)
is Diploma’s thesis is addressing the issues of technical drying, principles and types of technical drying, solar drying possible usefulness of sewage sludge in the Czech Republic, its availability during the season, the legislation related to the processing of sewage sludge and design of pilot scale solar dryer.
113

Možnosti mikrobiální degradace a využití odpadů z potravinářských výrob / Prospects of Microbial Degradation and Waste Utilization from Food Processing Industry

Illková, Kateřina January 2012 (has links)
This work deals with the problem of microbial degradation of the waste materials from food industry. This work is focused on the production of technological significant enzymes producing by microorganisms, which were able to use the waste as a sole carbon source. In the first part of this work, the attention was focused on the production of pectolytic enzymes. This part was made within study interships in Slovak Academy of Sciences, department of Glycomics in Bratislava. The grape pomace as the waste form winegrowing was used as a sole carbon source for microbial growth and enzymes production. The production of pectolytic enzymes was tested on this waste. After screening the most suitable microorganisms was chosen with the highest production of polygalacturonase activity. Produced enzymes were isolated by extraction techniques, purified and then identified proteomically. The aim of the second part of this work was the waste water treatment containing lipids and lipolytic enzymes. The reason was the cooperation with the company constructing grease traps. The characterization of supplied commercial preparations was the subject of this work and the other reason was the characterization of conditions for lipases secreting by microorganisms, identification of microorganisms present in the commercial preparation and testing of new microbial cultures for the development of new preparation for the grease traps.
114

Vliv obecní čistírny odpadních vod na jeskynní systém propadání Lopače / Effects of Municipal Wastewater Treatment Plant at Lopac Sinkhole Cave System

Ondruš, Martin January 2016 (has links)
The aim of this thesis is to assess the impact of water outflow from wastewater treatment plant on karst rivers. The study was done in the northern area of Moravský kras protected landscape, where the impact of WWTP Ostrov u Macochy on a cave system Lopačské propadání was studied. As a part of this study a half-year monitoring was carried out, which consisted of water sampling every two weeks. In total, 13 water samples were taken from 7 sampling points. Moreover, flow rate, temperature, conductivity, oxygen concentration and pH were measured at the sampling point. Afterwards, the content of undissolved solids, COD, BOD, N-NH4+, N-NO2-, N-NO3-, NKi and total phosphorus were determined in the samples. The change of parameters in time on the sampling points and further along the flow of the river was evaluated from the measured values. The outflow values from waste water treatment plants were compared with the emission limits for surface waters and the values of river water parameters were compared with the environmental quality standards. It wasn’t proven that the outflow from the observed waste water treatment plant is negatively influencing the water stream. The most serious problems are: -The WWTP was designed for treatment of sewage from Ostrov u Macochy, which involved separate sanitary and storm sewers. After finishing the WWTP, a uniform sewer was built. -High concentration of total phosphorus on the outflow from WWTP. -Poor quality of Lopač brook water already before the outflow vent from WWTP.
115

Fällning av kisel från avloppsvatten vid Hellisheidarvirkjun - experimentell studie / Experiments with precipitation of silica from waste water at Hellisheiðarvirkjun

ÓLAFSDÓTTIR, VERA SÓLVEIG January 2015 (has links)
This report is about the experiments with mixing of the separated water and the vacuum pump seal water at Hellisheiði power plant. This is done to prevent silica scaling and clogging in pipes and reinjection wells as well as eliminating vacuum pump seal water from the plant. The experiments were done in four stages: the first stage comprised of tests with different flows of separated water at 70°C, the second stage was carried out by mixing the separated water at 70°C and the seal water with different amounts of the seal water, the third and the fourth stages were like the first and second but with the separated water at 120°C. The results show that this method is good if the mixture is around 50/50 separated water and seal water, to control the silica scaling in the separated water and to be able to reinject the seal water with the separated water. This does not eliminate the silica scaling in all of the separated water because the amount of separated water is much more than the amount of seal water that comes from the plant.
116

OPTIMERING AV KVÄVEAVSKILJNINGEN PÅ AVLOPPSRENINGSVERKET I HALLSBERGS KOMMUN : EN TEKNISK-, EKONOMISK- OCH MILJÖMÄSSIG UTVÄRDERING

Grönlund, Lisa January 2011 (has links)
Avloppsreningsverket i Hallsberg kommun är beläget i direkt anslutning till Hallsberg, med Ralaån som recipient. Tekniken på reningsverket bygger på principerna för en klassisk aktivslamanläggning med mekanisk rening, kemisk rening, biologisk rening och en slambehandling där rötning av primär- och sekundärslam används för utvinning av biogas. Hallsberg ARV har under en längre tid haft problem med kvävereningen. Under senaste åren har man överskridit riktvärdet för kväveutsläpp vid ett flertal tillfällen och under 2009 överskreds även gränsvärdet. Riktvärdet för Hallsberg ARV är i dagsläget satt till 10mg NH4-N/l som medelvärde per månad, gränsvärdet är satt till 10 mg NH4-N/l som medelvärde per kalenderår. Då Hallsberg ARV inte drivs vid full kapacitet antas en minskning av kväveutsläppen vara möjlig att genomföra genom trimning av befintligutrustning och processer på verket. Detta antagande låg till grund för det här examensarbetet som syftar till att optimera kvävereningen på Hallsberg ARV. I optimeringen ingick en teknisk, ekonomisk och miljömässig utvärdering av olika alternativa lösningarna för att förbättra funktionen hos anläggningen. Extra hänsyn togs till energi- och kemikalieåtgång i syfte att få en så effektiv drift av verket som möjligt. Arbetet genomfördes genom en initial litteraturstudie på området, vartefter en provtagningsserie om fyra veckor realiserades på verket. Data som ligger till grund för slutsatserna i projektet har också inhämtats från onlinemätare på verket samt från äldre externt analyserade prover. Efter analys av insamlad data antas orsakerna till Hallsberg ARV:s höga utsläpp av kväve bero på en kombination av flera faktorer: -Vid vår och höst kan brunnsslamintaget vara så stort att bräddning sker ut till verket. Detta leder till att kvävebelastningen höjs så kraftigt att nitrifierarna inte hinner acklimatisera sig och får förhöjda kväveutsläpp till följd. -Mycket kväve följer med slammet från simultanfällningen till rötningen. Detta kan påverka halten kväve i rejektet från rötkamrarna som i sin tur kan leda till störningar i kvävereningen. -Centrifugens rejekt innehåller mycket kväve och körs idag endast under ett par dagar i veckan vilket leder till stora variationer i inkommande kvävehalt. -En hög förfällning av fosfor och organiskt material har bidragit till en låg halt av organiskt material i denitrifikationen. Sammantaget föreslås att vidare studier bör genomföras av ovan nämnda områden för att driften på Hallsberg ARV ska kunna drivas med så låga miljömässiga och ekonomiska kostnader som möjligt. / The waste water treatment plant in Hallsberg municipal is situated adjacent to Hallsberg, with Ralaån as a recipient. The technique at the waste water treatment plant is based on the principles for a classical activated sludge treatment plant and includes mechanical treatment, chemical treatment, biological treatment, and a sludge treatment where the digestion of primary and secondary sludge is used for extraction of biogas. Hallsberg waste water treatment plant has during some time had problems with the nitrogen removal with high nitrogen emissions as a consequence. The target value has been exceeded a couple of times during the last years and in 2009 the limit value was exceeded as well. The target value for Hallsberg waste water treatment plant is 10 mgNH4-N/l as an average value per month, the limit value is set to 10 mg NH4-N/l, as an average value per year. Since the waste water treatment plant in Hallsberg not is operating at full capacity, a lowering of the nitrogen emissions is assumed to be possible though a trimming of the existing equipment and of the processes on the site. This assumption formed the basis for this thesis, designed to optimize the nitrogen removal at the waste water treatment plant in Hallsberg. A technical, economical and environmental evaluation was included in the optimization to improve the function of the plant. Extra evaluations were made in the energy- and chemical consumption in order to streamline the operations at the plant as much as possible. The project was carried out through an initial literature-investigation followed by a four week period of sampling and analyzing at the site. The data that form the conclusion in this project has also been collected through online measurements at the plant as well as through analyses of older samples. After analyzing the collected data, the reasons for the high emissions of nitrogen is thought to be due to a combination of reasons: -During the spring and the autumn the external intake of well sludge can lead to a direct release of sludge in to the plant. The change of nitrogen content will not give enough time for the nitrifying bacteria to acclimatize, with elevated emissions of nitrogen as a consequence. -The usage of simultaneous precipitation could lead to an irregular concentration of nitrogen released to the treatment plant from the digesters. This in turn could contribute to higher nitrogen emissions. -The irregularities of the usage of the centrifuge contribute to nitrogen irregularities and contribute to the difficulties of acclimatization of the nitrifying bacteria. -A high pre-precipitation of phosphorus and organic matter has contributed to a level of organic material in the denitrifikation below what is recommended. To sum up, further investigations are suggested in the above mentioned areas to make the operations at the plant carried trough at the lowest possible environmental and economically cost.
117

Temperature optimization of anaerobic digestion at the Käppala Waste Water Treatment Plant / Temperaturoptimering av Käppalas rötningsprocess

Bramstedt, Sofia January 2016 (has links)
No description available.
118

Syntetické vonné látky v odpadních vodách / Synthetic aromatic substances in wastewaters

Tylichová, Petra January 2011 (has links)
Synthetic fragrances are artificially synthetised organic compounds which are used as fragrant substances in assorted personal care products, perfumes, cosmetics, soaps, detergents, cleansing articles, etc. So-called musk compounds creates significant group of synthetic fragrances which are distinguished by specific fragrance reminiscent of musk. Recently great attention is devoted to musk compounds because they were proved in different units of environment. The aim of diploma thesis was determination of selected linear musk compounds (arocet, aroflorone, linalool 925, lilial, isoamyl salicylate) in real samples of waste water in the influent and effluent from the sewage treatment plant Brno-Modřice. At first optimization of selected method was performed and then this method was used for own determination. Analytes were extracted by solid phase microextraction (SPME) from sample. Method of gas chromatography with mass spectrometry was used for own analysis. The results were used for evaluation of efficiency of removing linear musk compounds from waste water.
119

Odstraňování vybraných léčiv z odpadních vod oxidačními procesy / Removal of selected medicines from waste water by oxidation processes

Úterský, Michal Unknown Date (has links)
A concept of removing of pharmaceuticals from a wastewater is become more important topic. Currently we can see the increasing consumption of pharmaceuticals worldwide and an increasing effective doses of pharmaceuticals due to the resistance of microorganisms. Generally, a medicine means an active substance or their mixtures. The medicine is used for positive influencing of human’s and animal’s health. Nevertheless, a long term presence of pharmaceuticals in the environment leads to chronic toxic aquatic organisms, possibilities of multiplication of multi-resistant pathogenic bacterial strains, deterioration of reproduction of animals and their endocrine system. My dissertation is focused on a removing of pharmaceuticals from the wastewater via advanced oxidation processes. Results of research showed that the advanced oxidation processes are able to reduce concentration of pharmaceuticals. Mainly priority of this problem is other cleaning level of the wastewater which flows away from urban WWTP to river. Wastewaters consist of large volume of pharmaceuticals due to excrements, urination and flushing of outdated pharmaceuticals. An efficiency of advanced oxidation processes on the removal selected types of pharmaceuticals is a part of practical selection of the dissertation.
120

Influence of Land Cover, Stream Discharge, and Waste Water Effluent on Suspended Sediment and Nutrient Concentrations in Southwest Ohio Streams

Spahr, Rachel Elizabeth 01 July 2019 (has links)
No description available.

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