No description available.

This paper is about improving the efficiency of nitrogen and other organic nutrient removal from activated sewage treatment by adopting an innovative technology. The work is to study the changes in nitrogen removal in pilot-scale experiments with the ITEST unit. The report also describes the various sources contributing to the eutrophication of the sea and water, caused by an increase in nutrient levels in different water bodies. Ineffective treatment of sewage contributes to the eutrophication. In the Baltic regions the temperature will be zero (0) or less than zero degree-centigrade during winter season. It results in decreased or fall in temperatures of incoming water to wastewater treatment plants. The temperature is an important parameter for sewage/wastewater treatment processes. Bacteriological nitrification and denitrification is an effective process for removing nitrogen from wastewater. From various research works and articles, it can be found that 23 + / - 2 °C, is the optimum temperature for nitrification and denitrification processes. So, the main aim is to study the effect of maintaining the incoming wastewater temperature by use of heat exchangers on incoming water to an activated sludge process line in pilot plant scale. In the pilot plant there were two testing lines; one line with heating system and the second line without heating system. A temperature of 19 to 20 °C was maintained in the influent to testing line. The nitrogen removal rates were compared between the two lines during the test period of approximately more than 8 months. Other biological activities in the treatment process were also compared between the two lines.

This study describes the variation of an important greenhouse gas, nitrous oxide (N2O) at site-specific from the bio-lines unit at Wastewater Treatment Plant (WWTP) in Halmstad. The sampling campaign at the WWTP was carried out for three consecutive days during the weekdays in March 2021 with total of 144 samples were taken in GHG sample vials (exetainers) and analysed for N2O measurements using gas chromatography. Other nitrogen parameters data (NO2-N, NO3-N, and total nitrogen) were also collected. Using statistical analysis, comparisons were focused on a year period (March 2020 and 2021). This study found that N2O concentration generated in March 2021 was significantly lower than March 2020. Results also showed significant differences of N2O concentration between the three different zones (anaerobic, anoxic, and aerobic) among the bio-lines, where the highest N2O concentration was only found in aerobic zones. Correlation analysis showed only total nitrogen is negatively correlated with N2O-N in the aerobic zones. These findings will enable better understanding of processes along the bio-lines as a step for WWTP operators to improve N2O monitoring.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20009号 / 農博第2193号 / 新制||農||1045(附属図書館) / 学位論文||H28||N5018(農学部図書室) / 33105 / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 小川 順, 教授 阪井 康能, 教授 栗原 達夫 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

No description available.

No description available.

This research entails the investigation of the effects of a bioaugmentation product from BiOWiSH® called Aqua, referred to as “Aqua” for the remainder of this paper, on the nitrogen removal rate in a membrane aerated bioreactor (MABR). This research was conducted using a MABR design that consisted of a silicone membrane and continuous flow airline with compressed air. The membrane system was designed to supply oxygen, creating an aerated layer at the membrane-biofilm interface and an anoxic layer at the biofilm-water interface. Laboratory experiments were conducted to compare the nitrogen removal rates of natural bacteria alone to natural bacteria paired with Aqua. However, it was not possible to determine if a difference existed between the nitrogen removal rates of the MABR systems with only natural bacteria versus those with natural bacteria augmented with Aqua. The mean nitrogen removal rate observed when the media in the system reached steady state was 0.39 mg-N/L-hr. with a carbon to nitrogen (C: N) ratio of 12:1. The only increase in the nitrogen removal rate observed was when the C: N ratio was doubled to 24:1 and the nitrogen removal rate increased to 0.56 mg-N/L-hr. Although it appeared that the Aqua did not have an influence on the nitrogen removal rate in the MABR systems, many other variables still need to be assessed to reach a conclusion. To improve the efficiency of the system more tubing should be added, or the glucose should be removed from the growth media because the maximum O2 mass transfer rate is only enough O2 for nitrification. The addition of glucose at 12:1 ratio increased the O2 demand in the system to be five times greater than the O2 supplied from the silicone tubing. This research determined that use of trace minerals, Aqua dosing method, and Aqua dosing concentration were not contributing factors in nitrogen removal from growth media under the conditions of this experiment.

M.S.

In 2014 SÖRAB constructed a continuous biological treatment system (KBR) to handle leachate waterfrom the landfill at the facility in Löt, north of Stockholm. The KBR is mainly focused on removal ofammonium nitrogen which would otherwise be released in to the recipient and contribute toeutrophication and damage to the environment. This project has focused on replacing the currentcarbon source in the process Brenntaplus VP1 and evaluating the efficiency of denitrification andeconomy of transitioning to a new carbon source. The carbon sources glycerol and ethanol wereevaluated and compared to Brenntaplus VP1 for the denitrification efficiency and microbial profile.The experiments were performed in laboratory conditions and in pilot scale using leachate water fromLöt. The reduction of ammonia was evaluated by chemical precipitation, addition of carbon sources bymeasuring ammonia-N and nitrate-N under aerobic (nitrification) and anaerobic (denitrification)conditions. The combination of ethanol and glycerol showed an enhanced denitrification and increasedmicrobial community both in lab and pilot scale studies with reduced hydraulic retention time. Therate of nitrate reduction was 0.23 mgNO3-N 1 -1 h -1 for ethanol/glycerol compared to 0.12-0.17mgNO 3- -N 1 -1 h -1 for Brenntaplus VP1 in pilot scale. The results indicate that using ethanol, glycerolor a mix of the two as a substitute for Brenntaplus VP1 is viable. This has been based on laboratoryand pilot scale studies. Each of the carbon sources examined during this project have showed a uniqueimpact on the process and its parameters such as: denitrification rate, microbial density and microbialcomposition. The carbon sources had an impact with temperature fluctuation and faster denitrificationcompared to the conventional KBR system. This implies that the carbon sources tested in this projectcan be advantageous and beneficial for Sörab depending on the carbon source availability and theseasonal variations. / Under 2014 konstruerade SÖRAB ett kontinuerligt biologiskt reningsverk (KBR) för att hanteralakvatten från deponin för ickefarligt avfall vid anläggningen i Löt, norr om Stockholm. KBR ärfrämst konstruerad för rening av ammoniumkväve som annars skulle släppas ut till recipienten ochbidra till övergödning och skador på miljön i området. Detta projekt har fokuserat på att ersätta dennuvarande kolkällan Brenntaplus VP1 som används i processen och utvärdera effektiviteten idenitrifieringen samt ekonomin vid övergång till en ny kolkälla. Kolkällorna glycerol och etanol varde kolkällor som valdes för utvärdering i detta projekt, dessa jämfördes med Brenntaplus VP1 i desseffekt på denitrifikationseffektivitet och mikrobiell sammansättning under laboratorieförhållanden ochi pilotskala. Möjligheten att reducera ammoniumkoncentrationen i lakvattnet utvärderades genomkemisk fällning och genom mätning av ammoniumkväve och nitratkväve under aeroba (nitrifikation)och anaeroba (denitrifikation) förhållanden. Kombinationen av etanol och glycerol indikerade enförbättrad denitrifikation och ökad mikrobiell densitet både i laboratorie- och pilotskala med reduceradhydraulisk retentionstid. Nitratreduktionshastigheten var 0,23 mgNO 3- -N 1 -1 h -1 för blandningen avetanol/glycerol jämfört med 0,12 - 0,17 mgNO 3- -N 1 -1 h -1 för Brenntaplus VP1 i pilotskala. Resultatenindikerar att användning av etanol, glycerol eller en blandning av de två har goda förutsättningar föratt ersätta Brenntaplus VP1. Var och en av de tre kolkällorna som undersöktes under detta projekt harvisat en unik inverkan på processen och dess parametrar såsom: denitrifikationshastighet, mikrobielldensitet och mikrobiell sammansättning. Genom att byta kolkälla i KBR kan prestandan ökas genomatt minska den hydrauliska retentionstiden samtidigt som systemet tycks bli mindre känsligt förtemperatursvängningar. Kolkällorna som utvärderats i detta projekt kan därför vara fördelaktiga för SÖRAB beroende på dess tillgänglighet och pris.

This study was done with the aim of deepening the understanding of the Maya Chay aquaponic systems. To meet the aim, a literature study on aquaponics, with an emphasis on the nitrogen metabolism in such systems, was conducted. Furthermore, a deep investigation of the specific Maya Chay systems was made to understand how these systems might be different from the general aquaponic designs. Finally, two nitrogen balances were developed with the purpose of examining the dynamics of the nitrogen transformations in two Maya Chay aquaponic systems. The measurements for the nitrogen balances was made between Mars 2017 to July 2017, and the model for the nitrogen balances evaluated the amount of nitrogen as: i) nitrogen input to the system through the feed, ii) nitrogen assimilated by the fish and the plants, iii) nitrogen accumulated in the sludge, and iv) nitrogen lost to the atmosphere through denitrification and similar processes such as anammox. The resulting nitrogen balances showed some interesting differences in the dynamics of nitrogen distribution. In the smaller Maya Chay XS system in Antigua, only 36 % of the nitrogen input was assimilated by the fish (30 %) and the plants (6 %) and 64 % of the nitrogen input could be regarded as lost, either to the atmosphere (46 %) or in the sludge (18 %). The other nitrogen balance showed that the distribution of nitrogen in the Maya Chay S system in Chinautla is much more efficient in taking care of the nitrogen input. In this system 70 % was assimilated by the fish (33 %) and the vegetables (37 %) and the remaining 30 % was lost, either to the atmosphere (14 %) or in the sludge (16 %). The nitrogen balances also showed that both systems are almost equally efficient in terms of nitrogen assimilation by the fish, and that the big differences lie in the rate of nitrogen assimilation by the plants (6 % vs. 30 %) and in the nitrogen loss to the atmosphere (46 % vs. 14 %). A likely explanation for these differences is the difference in design of the vegetable beds, where the less efficient system in Antigua has a large surface area for the vegetable bed, but only a small portion of this could be utilized for vegetable growth. Furthermore, a consequence of the larger surface is a larger anoxic zone in the bottom of the vegetable bed, which promotes the growth of denitrifying and anammox bacteria. These kinds of bacteria convert the dissolved ammonia, nitrite and nitrate to gas forms of nitrogen, such as nitrogen gas and nitrous oxide and thus nitrogen is lost from the system to the atmosphere. Finally, this study also showed a great difference in the ratio of vegetable to fish production between the systems, where the ratio was 0.43 in Antigua and 2.7 in Chinautla. This ratio further indicates the difference in design between the systems, especially regarding the vegetable beds, has an impact on how well they perform, both in terms in economic and productivity terms, but also in terms of the release of greenhouse gases (nitrous oxide). It can therefore be concluded that the original design of the Maya Chay system (i.e. the Chinautla system) is the preferable one. Even though the accuracy of the measurements in the experiments could be improved for future studies, this study has demonstrated the value of making nitrogen balances for aquaponic systems. Nitrogen balances increase the knowledge of the performance of the system and they increase the understanding of the dynamics of nitrogen transformations that takes place in the system. This knowledge can then be utilized to adjust the design and/or verify if either the aquaculture or hydroponic system is properly designed. / Den här studien gjordes med syftet att fördjupa förståelsen kring Maya Chay akvaponiska system. För att uppnå syftet, utfördes en litteraturstudie som fokuserade på metabolismen av kväve i sådana system. Vidare undersöktes specifika Maya Chay system för att förstå hur dessa system skulle kunna skilja sig från den generella akvaponiska designen. Slutligen utvecklades två kvävebalanser i syfte att utforska dynamiken i de kväveomvandlingar som sker i två Maya Chay akvaponiska system. Mätningarna för kvävebalanserna gjordes i perioden mars 2017 till juli 2017, och modellen för kvävebalanserna utvärderade mängden kväve som: i) kväve som tillförts till systemet genom fodret, ii) kväve som assimilerats av fiskarna och växterna, iii) kväve som ackumulerats i slammet, och iv) kväve som gått förlorat till atmosfären genom denitrifikation och liknande processer så som anammox. Resultaten från kvävebalanserna visade intressanta skillnader kring dynamiken av kvävefördelningen. I det mindre Maya Chay XS systemet i Antigua, assimilerades endast 36 % av kvävet av fiskarna (30 %) och växterna (6 %) och 64 % av kvävet ansågs som förluster, antingen till atmosfären (46 %) eller genom slammet (18 %). Den andra kvävebalansen visade att fördelningen av kväve i Maya Chay S systemet i Chinautla är mycket mer effektivt gällande tillvaratagandet av tillfört kväve. I detta system assimilerades 70 % av fiskarna (33 %) och av växterna (37 %) och de resterande 30 % gick förlorat, antingen till atmosfären (14 %) eller i slammet (16 %). Kvävebalanserna visade även att bägge systemen är mer eller mindre likvärdiga gällande assimilering av kväve från fiskarna, och att den stora skillnaden mellan systemen ligger i hur mycket kväve som assimilerats av växterna (6 % vs. 37 %) samt hur mycket kväve som gått förlorat till atmosfären (46 % vs. 14 %). En sannolik förklaring till dessa skillnader är skillnaden i designen av växtbäddarna för två systemen, där det mindre effektiva systemet i Antigua har större area för växtbädden, men endast en mindre del av denna kunde nyttjas för odling av grönsaker. Som konsekvens av den större arean av växtbädden är en större volym syrefattigt vatten i botten av växtbädden, vilket verkar för tillväxt av denitrifierande och anammoxa bakterier. Dessa typer av bakterier omvandlar den upplösta ammoniaken, nitriten samt nitratet till kväveföreningar i gasform, till exempel kvävgas och lustgas och därav går kvävet förlorat till atmosfären. Slutligen visade den här studien stora skillnader i förhållandet mellan växt- och fisk-produktion mellan de två systemen, där förhållandet var 0.43 i Antigua och 2.7 i Chinautla. Skillnaden mellan de två olika förhållandena är ytterligare en indikation till att skillnaden i designen mellan systemen, speciellt med avseende på växtbäddarna, har en effekt på hur väl systemen presterar, både i termer som ekonomi och produktivitet, men också i termer som utsläpp av växthusgaser (lustgas). Därför kan slutsatsen dras att den ursprungliga designen av Maya Chay systemen (det vill säga systemet i Chinautla) är att föredra. Även om noggrannheten i mätningarna i detta experiment skulle kunna förbättras i framtida experiment, så visar denna studie värdet av att utföra kvävebalanser för akvaponiska system. Kvävebalanserna ökar kunskapen om hur väl systemen fungerar och dom ökar kunskapen kring dynamiken i kväveomvandlingarna som sker i systemen. Denna kunskap kan sedan utnyttjas för att justera designen av systemen och/eller verifiera om antingen vattenbruksdelen eller hydroponidelen i systemet är feldimensionerad.