This study focuses on the relationship between hydrological and nutrient conditions in seawater surrounded by Dongsha Atoll. Dongsha Atoll is located in the northern South China Sea (NSCS), the water properties should be in coherence with the NSCS water masses. However, due to the semi-enclosed topography the water inside Dongsha Atoll is largely affected by local insolation and rainfall. Significant relationships between SiO2 or PO43- and salinity indicate that rainfall could be a major source of these nutrients. Insignificant relationship between N+N and salinity indicates that rainfall and nitrogen fixation both might affect the distribution of N+N. Temporal variations of temperature and chlorophyll a were alike, except for which occurred in July, 2011. It was probably caused by photo inhibition on phytoplankton growth. The inventory of chlorophyll a was positively correlated with both N+N and SiO2 but not with of PO43-, indicating that phytoplankton growth in Dongsha Atoll was mainly affected by N+N and SiO2. Phytoplankton growth maybe limited by N+N but not by SiO2, as the concentration of SiO2 was mostly beyond the limitation concentration for phytoplankton. According to close relationships between chlorophyll a and TSM, POC and PN, the particulate matter maybe mainly derived from biological origins. The inventory of chlorophyll a was positively correlated with both dissolved organic carbon (DOC) and dissolved organic nitrogen (DON), manifesting the importance of biological origins for DOC and DON concentration. The ratios of DOC/DON, DON/DOP and DOC/DOP within the atoll were in ranges of 7.34-303 (mean: 30.4), 3.00-142 (mean: 22.7) and 104-2546 (mean: 421), respectively. The ratios are higher than those values in NSCS and East China Sea, implying the excretion of carbon-enriched DOM by phytoplankton. The concentration of chlorophyll a, DOC and POC were higher in the Small Lagoon than in the Atoll Lagoon, implying a relatively high productivity in the Small Lagoon. The fluxes of carbonate in the atoll was more than 30 times of the flux in the NSCS, due to its unique characteristics in the coral reef habitat. The organic matter of settling particulates was mainly derived from biological sources. The metal of enrichment factor of settling particulates reveals that Fe and Al are mainly derived from crustal sources, while Cu, Zn and Pb are likely influenced by anthropogenic sources.

This study reports the first sediment trap mooring results obtained under the SIBEX program (South China Sea Integrated Biogeochemical Experiments). Two strings of sediment traps were deployed respectively at M1 located to the southwest of Taiwan, and M2 in the northern basin of the South China Sea (SCS). Box cores were also taken at several sites to the south of M2. The main purposes are to measure settling particulate fluxes at various depths for the studies of temporal and spatial variations of the particulate flux and 210Pb activity. The box cores were used to determine the sedimentation rates. These are to enhance our understanding of the characteristics of the particulate distribution and the roles the particulate matter plays in the biogeochemical processes in the SCS. Particulate fluxes measured from different depths at M1 and M2 generally increase with depth. In temporal variation, M1 has higher amplitudes than M2, with highest amplitudes at 948 m where highest flux (2025 mg/m2/d) was observed. The particulate flux at 948 m has higher values than at 248 m, probably due to lateral transport. At M2, the particulate flux at 240 m has higher values with greater amplitudes than at greater depths, i.e. 1240 m, 2240 m and 3240 m, where their particulate fluxes show a synchronous trend with small amplitudes in temporal variation. The time-averaged particulate flux for each trap ranges from 199 to 554 mg/m2/d, consistently higher than previous observations (76~104 mg/m2/d). However, our values are comparable to the mean particulate flux (280 mg/m2/d) estimated from terrigenous inputs. The apparent changes in particulate flux in the SCS over the past ten years warrants further investigations. The temporal variations of Pb-210 show a synchronous trend and a rapid increase with depth as observed at M1 and M2. This rapid increase of Pb-210 with depth reflects effective scavenging by sinking particulates although particulate concentrations are low. The loss on ignition (L.O.I.) at M1 and M2 was inversely correlated with Pb-210, indicating that Pb-210 was expelled from biogenic particulates or organic matter. The particulate fluxes around 240 m at M1 and M2 were generally positively correlated with the L.O.I., suggesting that the high particulate fluxes are probably contributed by biogenic particulates or organic matter. The sedimentation rates as determined from excess Pb-210 profiles range from 9.01~23.13 cm/100yr. These rapid sedimentation rates reflect the effect of mixing and additional sediments accumulated through lateral transport. The surface layers of these cores were subject to perturbation and mixing, based on the penetration depths of the excess Pb-210. The Pb-210 flux estimated from the inventory of excess Pb-210 in the sediments is much greater than that observed from the traps, suggesting that additional Pb-210 has been accumulated via lateral transport and slumping of nearby surface sediments. Based on the mean particulate flux observed, one may roughly estimate the corresponding sedimentation rate of about 10 cm/ka, which is an order of magnitude lower than those determined by the excess Pb-210 method. Because the upper layers of the sediments have been strongly disturbed and mixed with the additional sediments accumulated through lateral transport, the sedimentation rates as determined by the excess Pb-210 method are probably over-estimated by a factor of 10 to 20.

The time-series sediment traps were deployed in the northern South China Sea (NSCS) to collect settling particles to study the spatial and temporal variations of particle fluxes, particle sources and particle compositions. Each recovered sample was analyzed to determine the particle flux, major compositions (OM, Carbonate, opal and lithogenic materials) and trace metals (Al, Fe, Mn, Cd, Zn). The data were employed to elucidate the biochemical processes in controlling particle and chemical fluxes. The results show that the particle fluxes vary significantly in time and space, and were apparently related to terrestrial inputs and monsoon-effected processes. Episodic events such as typhoon and earthquakes also effected the fluxes considerably. Vertical fluxes generally decreased with depth for biogenic components (POC, carbonate, opal) but increased with depth for the lithogenic component. Most lithogenic fluxes below the surface were likely derived from lateral transport and decreased with distance away from Taiwan Island. Biogenic fluxes in surface layers were generally higher in winter than in otherseasons, which may be resulted from the elevated primary production in winter. Typhoons also enhanced biogenic fluxes in surface layers but biogenic fluxes were diluted in deep layers by strong lithogenic fluxes. Carbonate dominated the biogenic fluxes in the upper layer and may play as the major ballast in the transportation of biogenic materials through the water column. The C/N ratios of organic matter increased generally with depth implying that nitrogen was preferentially decayed over carbon through the water column. Lithogenic elements such as Al, Fe, Mn were closely correlated and increased in fluxes with depth. However, microelements associated with biogenic materials (Cd, Zn) displayed a significant decrease in content with depth, showing a rapid recycling in water columns.

This laboratory column (125 cm high, 15 cm diameter) research investigated solids and P removal from liquid swine manure amended with calcium carbonate, magnesium sulphate, alum and polyacrylamide (PAM). Results showed that PAM was the most effective amendment for enhancing solids removal from manure containing 1% initial total solids (TS). The effectiveness of PAM was lower at 5% and 8% than at 1% due to resuspension of solids occurring at settling times beyond 4 h. After 24 h of settling, P removal from non-amended manure was comparable to that in amended manure and decreased with TS concentration for all amendments except alum, which was equally effective at all TS concentrations. These results indicate that, for manure containing 1% TS, P can be adequately removed by gravity separation without addition of chemical amendments while alum is a more effective amendment for removing P from manure containing higher (5% and 8%) TS.

This laboratory column (125 cm high, 15 cm diameter) research investigated solids and P removal from liquid swine manure amended with calcium carbonate, magnesium sulphate, alum and polyacrylamide (PAM). Results showed that PAM was the most effective amendment for enhancing solids removal from manure containing 1% initial total solids (TS). The effectiveness of PAM was lower at 5% and 8% than at 1% due to resuspension of solids occurring at settling times beyond 4 h. After 24 h of settling, P removal from non-amended manure was comparable to that in amended manure and decreased with TS concentration for all amendments except alum, which was equally effective at all TS concentrations. These results indicate that, for manure containing 1% TS, P can be adequately removed by gravity separation without addition of chemical amendments while alum is a more effective amendment for removing P from manure containing higher (5% and 8%) TS.

Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1980. / Includes bibliographical references.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 89-94). Also available via the Internet.

Dissertação(mestrado)-Universidade Federal do Rio Grande, Programa de Pós–Graduação em Aqüicultura, Instituto de Oceanografia, 2008. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2012-08-08T22:52:24Z No. of bitstreams: 1 Graziele.pdf: 800609 bytes, checksum: a78917e56fee21a2cd42824b8e828291 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-08-21T17:14:53Z (GMT) No. of bitstreams: 1 Graziele.pdf: 800609 bytes, checksum: a78917e56fee21a2cd42824b8e828291 (MD5) / Made available in DSpace on 2012-08-21T17:14:53Z (GMT). No. of bitstreams: 1 Graziele.pdf: 800609 bytes, checksum: a78917e56fee21a2cd42824b8e828291 (MD5) Previous issue date: 2008 / As fazendas de cultivo de camarões com altas densidades, liberam efluentes com altas cargas de nutrientes, provocando a degradação da qualidade da água. Isto gera preocupação a respeito do lançamento de efluentes dos cultivos. Em vista disto, este trabalho teve como objetivo avaliar a eficiência de um sistema integrado de bacia de sedimentação e biofilme na remoção de nutrientes. O estudo foi realizado em ambiente aberto, durante 45 dias. Foram utilizados três tratamentos: a) tratamento TC, sem substrato vertical; b) tratamento T50, superfície interna das caixas aumentada em 50% e c) tratamento T100, superfície interna das caixas aumentada em 100%. As caixas foram abastecidas com o efluente de um cultivo de camarão. Diariamente foram medidos o pH, a salinidade, o oxigênio dissolvido (OD) e a temperatura. Durante os primeiros 15 dias as coletas foram feitas a cada 5 dias, após esse período as coletas de água foram a cada 2 dias, e de biofilme diariamente. As análises de amônia foram feitas em todos os dias de amostragem. As análises de nitrito, nitrato e fosfato, foram feitas de todas as coletas até o 15º dia, e após esse período a cada 6 dias. Do biofilme, a matéria seca foi determinada de todos os dias coletados. A clorofila a analisada a cada 5 dias. E a estimativa de ciliados e flagelados nos dias 5, 10, 15 e 20. Os resultados mostraram que os tratamentos TC e T50 reduziram mais de 80% da amônia e fosfato em 10 dias. O tratamento T100 nos primeiros dias apresentou os menores valores de OD, pH e clorofila a, provocando um pico nas concentrações de amônia e fosfato, retardando a remoção destes nutrientes. Para todos os tratamentos após o 15º dia a concentração de fosfato sofreu uma elevação que se manteve até o final do experimento. Concluindo que ao dobrar a área disponível para fixação de biofilme há uma dificuldade de circulação nos tanques, e um aumento da respiração microbiana, tornando o sistema menos eficiente. Já a bacia de sedimentação sem biofilme, ou com 50% de acréscimo de substrato, ambos são eficientes. Portanto, o efluente deve permanecer na bacia de sedimentação por um tempo mínimo de 10 dias, mas não ultrapassando 15 dias, para não haver elevação nos níveis de fosfato. / The shrimp farms with high densities, release effluents with high loads of nutrients, causing water quality degradation. This creates concern about the release of effluents of cultures. In this work, we aimed to assess the efficiency of an integrated system of settling ponds and biofilm in the nutrients removal. The study was conducted in an open environment, for 45 days. We used three treatments: a) treatment TC, without vertical substrate b) treatment T50, inner surface of the tanks increased by 50% and c) treatment T100, inner surface of the tanks increased by 100%. The tanks were supplied with the effluent of a shrimp culture. Daily were measured pH, salinity, dissolved oxygen (OD) and temperature. During the first 15 days the collections were made every 5 days, after that period the collection of water were every 2 days, and biofilm daily. Analyzes of ammonium were performed on all days of sampling. Analyzes of nitrite, nitrate and phosphate, were made of all collections until the 15 th day, and after this period every 6 days. Of the biofilm, the dry matter was determined in every day collected. The chlorophyll-a reviewed every 5 days. And the estimate of ciliates and flagellates on days 5, 10, 15 and 20. The results showed that the treatments TC and T50 reduced more than 80% of ammonium and phosphate in 10 days. The treatment T100 in the first few days showed the lowest values of OD, pH and chlorophyll-a, causing a peak in the concentrations of ammonium and phosphate, delaying the removal of these nutrients. For all treatments after the 15 th day the concentration of phosphate has an elevation which remained until the end of the experiment. Concluding that to double the area available for setting biofilm there is a difficulty in circulation in tanks, and an increase in microbial respiration, making the system less efficient. Already the settlement ponds without biofilm, or with 50% increase in substrate, both are effective. Therefore, the effluent must remain in the basin settling ponds for a minimum time of 10 days but not exceeding 15 days, for no elevation in the levels of phosphate.

Les étoiles, durant les premiers millions d’années de leur existence, sont entourées d’un disque composé à 99% de gaz et à 1 % de poussière. La poussière est initialement sous forme de grains de taille sub-micrométrique mais évolue jusqu’à pouvoir former les planètes. Grâce à l’interféromètre du plateau de Bure, avec lequel nous avons observé aux longueurs d’onde millimétrique, l’évolution temporelle ainsi que la distribution radiale des grains de poussière a pu être mise en évidence sur de nombreux disques. Par ailleurs, l’important gain en résolution et sensibilité d’ALMA, un nouvel interféromètre très performant basé au Chili, a nécessité l’amélioration de notre code de transfert radiatif afin de déterminer si et comment il allait être possible d’observer la sédimentation de la poussière, étape préalable à la formation des planétésimaux. / The stars, during the first millions years of their existence, are surrounded by a protoplanetary disk composed of99 % of gas and of 1 % of dust. The dust is initially under the form of sub-micrometric grains but evolves to likelyform planets. Thanks to the Plateau de Bure interferometer, with whom we observed at the millimeter wavelengths, the temporal evolution as well the radial distribution of the dust grains has been bringing to light in several disks.In addition, the important gain in resolution and in sensibility of ALMA, a new interferometer based in Chili, has required the improvement of our transfert radiativ code in order to determine if and how it will be possible to observe the dust settling, preliminary step for the formation of planetesimals.

Fettavskiljarslam är ett avfall som uppstår hos restauranger och på platser där matfett och matoljor används. För att förhindra att fettet sätter igen avlopp fångas det upp med en fettavskiljare. Dessa fettavskiljare töms sedan av slambilar som vidare lämnar slammet antingen för mellanlagring eller direkt för rötning och bildandet av biogas.   Ragn-­‐Sells AB hanterar ungefär 27 000 ton fettavskiljarslam varje år. 6000 ton av dessa placeras i  mellanlagringscistern på  Högbytorp  där  en  settlingprocess får  äga  rum.  Resterande  slam lämnas av logistiska skäl direkt för rötning. Mellanlagringscisternen vattendras med jämna mellanrum för att göra plats åt nytt slam. Vattenfasen tillsätts en av företagets andra processer, en rötslurry som sedan utnyttjas i rötningsprocesser.   Genom att hitta en metod för avvattning av slammet som fungerar enkelt och snabbt och är ekonomisk försvar kan slammet i stället för att lämnas för rötning bli en attraktiv råvara för till exempel biodrivmedel. De ändamål för materialet som undersökts är som råmaterial för produktion av biodiesel, förbränning som mixed fatty acids, rötning samt pyrolys. Vid biodieselproduktion spelar vattenhalt och halten av fria fettsyror en stor roll och ska slammet förbrännas är det viktigt att värmevärdet är högt samt att askalten är låg och att innehåll av eventuella tungmetaller är av låga nivåer.   Metoderna som undersökts för avvattning är settling, uppvärmd settling samt frysning av slammet. Frysning kan ske på tre olika vis. Frysa, tina och sedimentera, frysa, tina och dränera samt genom att frysa och separera. Analyser såsom värmevärde med bombkalorimeter, vattenhalt  med  Karl  Fisher-­‐titrering,   askhalt  och  torrsubstanshalt  genomfördes  sedan  på avskiljd fettfas. Även en metallanalys med ICP genomfördes samt kontroll av halt fria fettsyror som genomfördes av externt laboratorium.   Analyserna visar att den metod som bäst avvattnat fettet är att frysa och separera. Högst värmevärde får dock fettfas från den uppvärmda settlingen. Metod kan komma att väljas och ändras beroende på vad slammet ska användas till i nästa steg. Är biodieselproduktionen målet bör den metod som ger lägst vattenhalt väljas. Ska fettet utnyttjas för förbränning och kanske i framtiden ersätta fossila bränslen ska den metod som resulterar i högst värmevärde väljas.   Fettavskiljarslam är ett svårarbetat material, mycket på grund utav dess otrevliga odör, men det är också ett avfall som har högt energiinnehåll, är koldioxidneutralt samtidigt som det har stor potential att hjälpa människan att minska oljeberoendet. / Trap grease is a sludge that appears at restaurants and other facilites that uses fats and oils in their everyday work. To avoid clogging in the drains and sewer a grease trap is utilized. The grease traps are then emptied by sludge cars and from there either stored or directly delivered for production of biogas trough digestion. The storage is emptied on water to make room for more sludge. This water can contribute with moist and other nutrients for one the company’s other processes a sludge aimed for digestion.   Ragn-­‐Sells AB annually handles about 27 000 tonnes of trap grease, 6000 which is placed in intermediate storage and the rest left for production of biogas.   Finding a method for dewatering the sludge that is uncomplicated and economically justifiable could turn the sludge into a attractive feed stock for bio fuels, for example as a raw material in the production of bio diesel. Other purposes of the sludge could be combustion as mixed fatty acids, pyrolysis and also production of bio gas. If the sludge would be a component in production of bio diesel the water content need to be as low as possible the content of free fatty acids also needs to be low. If the sludge would be used for combustion the heating value should be high as high as possible and the ash residue is desirable to keep low.   The methods for dewatering tested in this work is a settling method, heated settling and also by freezing the sludge. The freezing can be performed in three ways. By freezing, thawing and sedimentation, by freezing, thawing and drain and at last freezing and separate. The analysis performed on the separated fat phase were testing of heating value with a bomb calorimeter, measuring of water content with Karl Fisher titration, ash residue and dry matter content. Analyses of metals in the sludge were done with inductively coupled plasma and an external laboratory analyzed the content of free fatty acids.   The results of the analysis showed that the best method for dewatering the sludge is to freeze and separate. The highest heating value was however showed by the heated settling method. Depending on the purpose of the sludge one or the other method may be chosen.   Trap grease is a complicated material to work with, most because of its unpleasant odor. But it is also a waste material that is rich in energy, is carbon dioxide neutral and has great potentials to help human kind to reduce the oil dependency.