Dissertations / Theses on the topic 'Fertilizer treatments'
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Owen, Gordon Thomas. "Energy analysis of various tillage and fertilizer treatments on corn silage production." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63267.
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Oebker, N. F., W. T. Molin, and R. Gibson. "Effect of Methanol Treatments on Chile Pepper and Seedless Watermelon Production in Central Arizona, 1993." College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/214716.
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Trenholm, Leif. "Effects of water table depths and fertilizer treatments on yield and quality of tomatoes." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22818.
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A field lysimeter experiment was conducted during 1993 and 1994 using 4 water table depths (WTD) (0.3, 0.6, 0.8, and 1.0 m), 13 treatment levels of calcium (0, 1500, and 2500 kg/ha) and potassium (0, 160, and 400 kg/ha), to determine their effects on tomato quality and yield. Plant parameters measured included: yield (fruit/plant), fruit height, maximum and minimum equatorial width, degree of catfacing (scale of 1 to 5), and sunscald (scale of 0 to 2).Water table treatment was usually highly significant for the parameters measured at harvest. Largest height, equatorial width and yield of tomato fruit occur with 0.6 to 0.8 m WTD. Fertilizer treatments were rarely significant by WTD, but if they were, they tended to be in the 0.3 or 1.0 m WTD. Maintaining a WTD of 0.6 to 0.8 m and fertilizing with 160 kg/ha of K can improve quality and total yield of tomatoes.
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Hudson, Donna. "Analysis of the effects of treatments on non-linear models for nitrogen response curves, with implications for design." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360011.
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Fortuin, Jordache. "Desktop study on Novel Treatment techniques to treat industrial fertilizer effluent." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29878.
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Fertilizer production is a massive global industry with the global consumption of the three main fertilizer nutrients, nitrogen, phosphate and potassium estimated at 187 million tonnes in 2016 with an anticipated annual growth of approximately 2% for the foreseeable future. In 2016 the global fertilizer market was estimated to have an overall market value of 141 billion US dollars. Fertilizer production produces significant liquid waste as process water used for the various separations, cleaning, emulsifying and dilution processes absorbs various nutrients and contaminants from these production processes. This liquid waste has characteristically high concentrations of nutrients derived from the base fertilizer, such as various dissolved phosphate compounds for phosphate-based fertilizer production or dissolved nitrogenous compounds for nitrogen based fertilizer production. These contaminants are inherently nutrients that could be recovered for beneficial re-use. The phosphate and potassium minerals used in fertilizer production are obtained from ores mined from the earth, thus the re-use of these mineral present particular significance when taking into accounting the declining global supply of these ores. Furthermore, if these liquid wastes are not disposed of correctly they can lead to detrimental environmental impacts such as eutrophication and ecological degradation in water courses. This study addresses this problem by presenting three novel treatment techniques to treat the liquid waste produced from a fertilizer production plant. A liquid waste sample obtained from a particular fertilizer production plant producing primarily nitrogen-based fertilizer is used as a design basis to evaluate the three presented treatment techniques. The techniques are evaluated based on their economic feasibility, technical feasibility and resource recovery ability. The three treatment techniques studied were the Sharon-Anammox bioreaction process, electrodialysis with struvite recovery process and combined forward-reverse osmosis process. The technical feasibility of the processes was primarily evaluated based on the effluent water quality from the treatment systems. The effluent quality index (EQI) was used as a comparative measure of the effluent quality of the processes. All three processes were found to perform inadequately from a technical feasibility perspective as demonstrated by the negative EQI values obtained for the processes. The Sharon-Anammox bioreaction process was found to perform poorly because its application is limited to treatment of waste streams containing high ammonia concentrations such as in conventional domestic waste. Therefore, the Sharon-Anammox process was not suited to the fertilizer effluent which also contained high nitrates, phosphates and total dissolved solids. The electrodialysis process performed poorly as it was unable to effectively remove the ammonium cations from the process water. The combined forward-reverse osmosis process performed poorly because a resource recovery step was not included to treat the concentrated waste stream discharged from the forward osmosis step of the process. It was identified that a similar struvite recovery step should be added to the combined forward-reverse osmosis process to improve the technical feasibility of the process and to provide the process with resource recovery capabilities. From an economic feasibility perspective, it was found that the addition of the struvite recovery setup to the electrodialysis process increased the capital costs of the process to between 300% and 500% of the other two options. However, with the omission of the struvite recovery setup the capital costs of all three processes were in a similar range.
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Peters, Curtis Lee 1958. "SURFACE RESPONSE OF ONIONS TO CULTURAL TREATMENTS." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276358.
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Adogla-Bessa, Tsatsu. "Enzyme treatment of whole-crop wheat silage." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278039.
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Rademacher, Janet Hogan 1961. "GROWTH RESPONSE TO TWO JOJOBA (SIMMONDSIA CHINENSIS (LINK) SCHNEIDER) CLONES TO SIX PHOSPHORUS TREATMENTS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/291248.
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Mlambo, Patricia Zanele. "Exploring the fertiliser potential of biosolids from algae integrated wastewater treatment systems." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1013342.
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High rate algae oxidation ponds (HRAOP) for domestic wastewater treatment generate biosolids that are predominantly microalgae. Consequently, HRAOP biosolids are enriched with minerals, amino acids, nutrients and possibly contain plant growth regulator (PGR)-like substances, which makes HRAOP biosolids attractive as fertiliser or PGR. This study investigated HRAOP biosolids as a starting material for a natural, cost-effective and readily-available eco-friendly organic fertiliser and/or PGRs. Various HRAOP extract formulations were prepared and their effect on plant growth and development was evaluated using selected bioassays. Initial screening included assessing the effect on change in specific leaf area, radish cotyledon expansion as an indicator of PGR-like activity, and seed germination index (GI). More detailed studies on fertiliser efficacy and PGR-like activity utilised bean (Phaseolus vulgaris) and tomato (Solanum lycopersicum) plants. Combined effects of sonicated (S) and 40% v/v methanol (M) extract (5:1 SM) had impressive plant responses, comparable to Hoagland solution (HS). Other potentially fertiliser formulations included 0.5% M, 1% M, 2.5% S and 5% S formulations. The 5:1 SM and 5% S showed greater PGR-like activity, promoting cotyledon expansion by 459 ± 0.02% and 362 ± 0.01%, respectively. GI data showed that none of the formulations negatively impacted germination. Further investigation showed that the 5% S formulation increased leaf length, width and area by 6.69 ± 0.24, 6.21 ± 0.2 mm and 41.55 ± 0.2 mm². All formulated fertiliser extracts had no adverse effect on chlorophyll content and plant nutrient balance as indicated by C:N (8-10:1) ratio. In addition, plants appeared to actively mobilise nutrients to regions where needed as evidenced by a shift in shoot: root ratio depending on C, N and water availability. Furthermore, 5% S caused a 75% increase in tomato productivity and had no effect on bean productivity. Whereas, 5:1 SM and 1% M formulation improved bean pod production by 33.3% and 11%, respectively but did not affect tomato production. Harvest index (HI) however indicated a 3% reduction in tomato productivity with 5:1 SM and little or no enhancement in bean productivity with both 5:1 SM and 5% S treatments. Bean plants treated with 5:1 SM and 5% S produced larger fruits, which could be an indication of the presence of a PGR effect. Overall, HRAOP biosolids extracts prepared and investigated in this study demonstrated both fertiliser characteristics and PGR-like activity with performances comparable and in some cases exceeding that of commercial products. However additional research is needed to confirm presence of PGR-like activities and fertiliser efficacy.
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Duffield, Simon John. "Spatial dynamics of invertebrate recovery in cereals following treatment with the insecticide dimethoate." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306256.
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Orndorff, Zenah Wilson. "Phosphorus adsorption on sandy mine tailings : a comparison of treatments with fertilizers, wood ash, and compost /." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-08142009-040609/.
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Sherwood, R. P. "On-farm treatment of barley straw with urea to improve digestibility and intake by sheep." Thesis, University of Reading, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371458.
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Rance, Logan T. "Understanding Student Perceptions of Biosolids and Other Fertilizers in Central Ohio." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587657377716495.
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Katugampalage, Lalith Gamini Perera Usanee Uyasatian. "Utilization of sludge from Biyagama common wastewater treatment plant as fertilizer and soil conditioner in Sri Lanka /." Abstract, 2007. http://mulinet3.li.mahidol.ac.th/thesis/2550/cd399/4837460.pdf.
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Shepherd, Jessica Grace. "Ochre and biochar : technologies for phosphorus capture and re-use." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28907.
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Despite recent instability in the global supply of phosphate-rock derived fertiliser and the potential for this to continue into the future, the recovery of phosphorus (P) from wastewater treatment systems, where P is abundant and accessible, is well below maximum potential. Considerable resource is spent on removing P from wastewater in order to comply with environmental standards and to protect aquatic ecosystems from eutrophication, yet there is little emphasis on capturing the P in a way that is optimised for re-using it as agricultural fertiliser. To address this lack of innovation in the face of climate change and food insecurity, a concept for a material capable of capturing P from wastewater was developed, with an emphasis on the utilisation of otherwise waste materials and the use of carbon neutral or negative production technologies. Based on the demonstrated P capture properties of coal minewater treatment waste (ochre) and biochar made from anaerobically digested feedstocks, a range of biochars were designed and produced using different mixtures of ochre (“OC”), sourced from the UK Coal Authority Minto minewater treatment scheme in Fife, Scotland and anaerobically digested sewage sludge (“AD”), sourced from the Newbridge wastewater treatment plant in Edinburgh. A first generation of materials consisting of either AD or a 1:1 mixture (dry weight basis) of OC and AD were produced in a small-scale batch pyrolysis unit at two pyrolysis highest treatment temperatures (HTTs) (450 and 550°C) to give the biochars AD450, AD550, OCAD450 and OCAD550. These were tested for their P capture properties in repeated P-exposure experiments with pH buffering in comparison to unpyrolysed ochre, activated carbon and a natural zeolite. After 5 days of repeated exposure to a P solution at a wastewater-relevant concentration (20 mg P l-1) replenished every 24 h, relatively high masses of P were recovered by ochre (1.73 ± 8.93×10-3 mg P g-1) and the biochars OCAD550 (1.26 ± 4.66×10-3 mg P g-1), OCAD450 (1.24 ± 2.10×10-3 mg P g-1), AD450 (1.06 ± 3.84×10-3 mg P g-1), and AD550 (0.986 ± 9.31×10-3 mg P g-1). The biochar materials had higher removal rates than both activated carbon (0.884 ± 1.69×10-2 mg P g-1) and zeolite (0.130 ± 1.05×10-2 mg P g-1). To assess the extractability of recovered P and thus potential plant bioavailability, P exposure was followed by repeated extraction of the materials for 4 days with pH 7-buffered deionised water. The AD biochars retained 55% of the P recovered, OCAD biochars 78% and ochre 100%. Assessment of potentially toxic element (PTE) concentrations in the biochars against guideline values indicated low risk associated with their use in the environment. A second generation of materials were produced to examine the scalability of the concept. Mixtures of AD and OC were pelletised with a lignin binder (89.1:9.9:1.0 ratio, dry weight basis) and AD was pelletised with binder (99:1 ratio, dry weight basis). The pelletised feedstocks were pyrolysed in a bench-scale continuous flow pyrolysis kiln at the same two HTTs to give the pelletised biochars PAD450, PAD550, POCAD450 and POCAD550. Analysis of digested biochar samples compared to the previous generation of biochars showed general similarities between the two groups, apart from the substantially lower Fe content. Sub-samples of the pelletised biochars were exposed to a 20 mg l-1 P solution over 6 days, with the solution replaced every 24 h to give the P-exposed biochars EPAD450, EPAD550, EPOCAD450 and EPOCAD550. To probe the mechanisms of P capture by these materials and how feedstock preparation and pyrolysis conditions affected these, spectroscopic analysis using laser-ablation (LA) ICP-MS, X-ray diffraction, X-ray photo-electron spectroscopy (XPS) and scanning electron microscopy coupled with energy dispersive X-ray was performed. The results highlighted the general importance of Fe minerals in P capture and subsidiary roles for Al, Ca and Si. A 3-week barley (Hordeum vulgare) seedling growth experiment was conducted using the pelletised and P-exposed biochars, in comparison with other biochars produced using feedstock which contained high amounts of PTEs. The biochars were also extracted using a range of different methods used to assess the bioavailability of PTEs and nutrients in soils, and the results compared to digests of barley leaves to identify whether any of these could reliably predict plant bioavailability in biochar. The above ground biomass and its total P concentration of barley grown in a 5% mixture of EPOCAD550 in sand was significantly higher than the control (p < 0.05 and p < 0.01, respectively). A significant positive correlation between mean leaf P mass and dry weight leaf yield (R2 = 0.865, p < 0.001) was found, indicating that dry weight yield could be used as an indicator for the P fertilising capability of biochar for barley seedlings. Element concentrations in unbuffered and buffered and (pH 7) 0.01 M CaCl2 biochar extractions were significantly positively correlated with plant leaf concentration for 6 of the 18 elements investigated, more than any of the other extractions. A longer barley growth experiment was conducted, using rhizoboxes, to test the bioavailability of P in the biochars compared to conventional fertiliser. The pelletised and Pexposed biochars were applied to a sandy loam soil with P constraints. Biochar application rates were based on 2% formic acid extractable P, calculated for summer barley using Index 0 soil. Analysis of total leaf length at harvest (12 weeks), dry weight yield, leaf P concentration and leaf P mass showed no significant differences between the biochar treatments, NPK fertilised and NK fertilised controls. This shows that biochar, when applied at low total application rates based on extractable P, is as effective as conventional fertiliser. Now that AD biochar materials have been shown to have useful phosphorus recycling properties in laboratory experiments, additional work is required to optimise their use in wastewater and agricultural systems. The next stage of research should determine their performance in flow-through filtration systems with simulated and real wastewater effluent, as well as their performance in field trials with different crops of interest to demonstrate their potential as viable alternative fertilisers.
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Elving, Josefine. "Pathogen inactivation and regrowth in organic waste during biological treatment /." SLU : Dept. of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/11652700.pdf.
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L'Espérance, Audrey. "Fertilize-this: Framing Infertility in Quebec, Ontario and England Between 1990 and 2010." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24288.
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Infertility politics implies a role for the state in regulating the relationships between different parties involved in the medicalized process of reproduction, namely would-be-parents (infertile couples or individuals), gamete donors, surrogate mothers, fertility specialists, etc. Policies adopted by the Canadian federal government in 2004 as regards assisted reproductive technologies (ARTs) were largely inspired by British regulations. Despite this similar start, Canadian policies never lead to implementation; the province of Quebec rapidly contested the federal Assisted Human Reproduction Act before the courts; and many issues of assisted conception were regulated in a heterogeneous manner by the provinces. Meanwhile in Britain, the implementation of the policies created many disparities among the regions of the country; the principle of the law was thoroughly contested and scrutinized; and the sites of deliberation were multiple in spite of the existence of a national regulatory agency. First, the author argues that assisted reproduction technologies cannot be taken as one policy domain, but is an umbrella label for a variety of policy issues. In that context, ARTs are unpacked in order to study, at the system level, the practices related to the overcoming of infertility. I focus on three sub-issues: access to fertility treatments, including the question of public funding and access criteria; gamete and embryo donation, including the question of filiation and donor conceived children’s right to know their biological origins; and surrogacy or the enforcement of pre-natal gestational surrogacy arrangements. Second, by mapping the variety of discourses and arenas mobilized by a range of actors, this study shows how framing and reframing dynamics influence public policies and their implementation. Third, by comparing frame mobilization and discursive dynamics between Quebec, Ontario and England this analysis demonstrates how frame alignment can be a necessary condition for a frame to be performative and influence policy outcomes. Depending on the context in which it occurs, frame transformation, amplification, extension or bridging can induce stability or trigger a cascade of events that will lead to policy change or to a change in the implementation of a policy.
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Nordin, Andreas. "Heavy metal removal from sewage sludge by pyrolysis treatment." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-8807.
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Sewage sludge is the product from wastewater treatment that mostly is considered as a waste material. However, it contains several nutrients, especially phosphorus, potassium and nitrogen which are excellent fertilizers. The downside is the harmful content it also carries with pathogens, heavy metals and a variety of organic pollutants that in many cases have unknown effects on the ecosystem. A possible solution to this problem could be to pyrolyse the sewage sludge and by that decrease the levels of heavy metals and also render both pathogens and organic pollutants harmless. In this thesis project pyrolysis of dried sewage sludge has been evaluated at temperatures 650 750, 850 and 950 °C with addition of chlorine in the form of PVC and straw. An energy balance for pyrolysis and drying of dewatered sewage sludge has also been suggested. The results of the pyrolysis evaluation indicate that cadmium concentration can be reduced significantly with increasing temperature in the product char. But also other heavy metals like lead and zinc are affected at the higher temperatures evaluated. Mercury is completely removed from the char residue. The more latent volatile metals copper, chromium and nickel cannot be reduced to lower concentrations at these temperatures. They are instead enriched under these conditions. Chlorine addition to the sludge enhances the evaporation of all heavy metals but copper, nickel and chromium. The energy balance over the system indicates that the drying process requires more energy than is released from the sludge into the pyrolysis gases. The energy carried by the pyrolysis gases is however larger than what is required to drive the pyrolysis process.
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Leon, Johanna-Louise, and Stephanie Gellberg. "Information om fertilitet och risk för infertilitet vid en cancerbehandling : En litteraturstudie om kvinnors upplevelse." Thesis, Högskolan i Halmstad, Akademin för hälsa och välfärd, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-42106.
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Bakgrund: Cancerbehandlingar kan medföra konsekvenser hos kvinnor så som skador på äggstocksvävnaden vilket kan leda till medicinsk infertilitet. Fertilitetskonservering är en metod för att bevara könsceller vid risk för infertilitet som bör erbjudas till kvinnor vid ett cancerbesked beroende på cancertyp, cancerbehandling och relationsstatus. Syfte: Litteraturstudiens syfte var att belysa kvinnors upplevelse av information om fertilitet och risk för infertilitet relaterat till sin cancerbehandling. Metod: Litteraturstudien genomfördes och grundades på åtta resultatartiklar, fem kvalitativa och tre kvantitativa. Resultat: Det finns en tydlig röd tråd i samtliga resultatartiklar att kvinnor upplevde att informationen relaterat till hur deras fertilitet kunde komma att påverkas av cancerbehandlingen varit bristande eller helt uteblivit. Vid information var upplevelsen ofta negativ och kvinnorna lämnades ovetandes med funderingar och tankar. Resultatet har delats in i två teman: Bristande information och Ojämlik information. Konklusion: Då vi i dagens samhälle har större chanser att överleva cancer än tidigare bör hälso- och sjukvårdspersonal prioritera individen och fokusera på livet efter cancern. Informationen som ges till patienter bör individanpassas för att ge patienter den bästa förutsättningen till familjebildning efter cancerbehandlingen.Background: Cancer treatments can have many consequences in women where damage to their ovarian tissue can lead to medical infertility. Fertilitypreservation is a method that should be offered to women undergoing cancer treatment to preserve gametes in women in risk of becoming infertile depending on cancer diagnosis, cancer treatment and relationship status. Aim: The aim of the literature study was to illuminate women's experiences receiving information regarding fertility and risk of infertility during a cancer treatment. Method: The literature study was based on five qualitative and three quantitative studies. Result: There's a distinct red line in women's experiences of lack off or no information at all related to how fertility could be affected by a cancer treatment. When informed the experience was mostly negative and women were left unknowing with reflections and thoughts. Out of the eight studies two main themes emerged: Lack of information and Non equal information. Conclusion: Because of the chances of cancer survival in todays society are higher than before the healthcare community needs to prioritize individuals and focus on life after cancer. Information given should be individualized for patients to enable the best conditions for family planning after a cancer treatment.
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Elliot, Alexander Dean. "An investigation into the hydrothermal processing of coal fly ash to produce zeolite for controlled release fertiliser applications." Thesis, Curtin University, 2006. http://hdl.handle.net/20.500.11937/1698.
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During the year that concluded prior to the commencement of this PhD (2001) 11.7 million tonnes of fly ash was produced in Australia, of which only 32% was utilised is some way, near its conclusion, the latest statistics (2004), reveal that 12.5 million tonnes was produced with only 35% utilised in some way (ADAA 2006), with the remainder being accumulated in landfills and ash dams. This low level of ash utilisation in Australia is inevitable due to the combination of inherently high transport costs, and relatively low value products. This situation argues for more value-added utilisation of coal ash to overcome the transport cost barrier.Zeolite synthesised from fly ash for agricultural application as a controlled release fertiliser, is a technology which offers considerable advantages in terms of economic, technical and environmental performance. This fertiliser market is both a high value and high volume market, with the potential to consume significant quantities of fly ash. Studies using natural zeolite have demonstrated significant improvements in fertiliser efficiency for zeolite compared to soluble salts.This thesis looks at the issues behind fly ash utilisation in the broader sense, evaluates the potential markets for zeolite products in Australia, assesses the established science behind producing zeolite materials from fly ash, and examines the direct hydrothermal treatment process for producing zeolites (including analcime, cancrinite, zeolite ZK-14, and zeolite P1) from coal fly ash, including the relationship between zeolite types produced and operating conditions, desirable zeolite properties for controlled release fertilisers, optimal production conditions, economic implications, and avenues for future research.The hydrothermal treatment process was studied through the control of reaction temperature (T), reaction time (t), the Si/Al mole ratio (n), the cation type (M), the pH, the H2O/Al mole ratio (p), and the M+/Al mole ratio in excess of unity (m), where MNO3 was used to control m independent of pH. A number of different zeolite types were produced from fly ash with a maximum zeolite yield of 57%. Due to impurities present in the fly ash, it is impossible to selectively synthesise pure zeolite of any kind using the direct hydrothermal treatment method, but this is adequate for the intended fertiliser applications.A systematic quantitative refinement method was developed using Rietica to characterise the mineralogy of fly ash and hydrothermal treatment products, resulting in substantially more information regarding the transformations taking place than has previous been available in the study of the synthesis of zeolites from fly ash. This in conjunction with SEM has provided unprecedented detail regarding the reactivity of fly ash components, namely glass, quartz, and mullite phases, as well as the independent role of M+ and OH− within the hydrothermal system, and the encapsulation of fly ash reactants by products.Notably quartz is more reactive than mullite; however at a pH of 14.6 mullite is completely dissolved while quartz is not, probably due to the significantly smaller size of mullite crystals relative to quartz particles; and for small increases in m with constant pH starting from x = 1, the total yield of zeolite increases, and the yields of different zeolite types change from low to a maxima back to low as functions of both pH and m.From the experiments conducted it appears that the processes of gel formation and zeolite crystal growth can be manipulated through the continuous presence of zeolites with fly ash reactants, and through the manipulation and control of M+ and OH− concentrations as well as temperature to balance the suppression of fly ash dissolution while enhancing crystallisation to minimise the encapsulation of reactants by products, increasing the productivity of hydrothermal treatment process, therefore improve its economic viability, which is key to its possible future implementation.
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Pim, Vanderlei. "Caracterização de iodo de esgotos de lagoa anaeróbia acondicionado em bags visando a sua disposição : estudo de caso - ETE Pedregulho/SP." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257806.
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Orientadores: Edevar Luvizotto Junior, Bruno Coraucci FilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: As preocupações com o adequado destino dos lodos de esgotos fizeram da reciclagem uma alternativa de grande perspectiva de evolução no Brasil. O presente estudo visa avaliar o lodo da lagoa anaeróbia da ETE Pedregulho/SP, operada pela Sabesp, bombeado e acondicionado em bags, em relação a sua qualidade, visando disposição. Foram utilizados 3 bags diferentes e realizadas análises antes, durante e depois do bombeamento, percebendo que, durante o tempo, as permeabilidades dos bags não são constantes e que, houve alterações nas caraterísticas do lodo quando nos bags. Foram removidos 614 m3 de lodo da lagoa anaeróbia, havendo melhora na eficiência da ETE. A retração volumétrica do lodo nos bags permitiu constatar a interferência das chuvas no volume dos bags. Houve também uma avaliação do líquido que percolava dos bags. O lodo foi caracterizado como resíduo Classe II A (não perigoso, não Inerte) pela ABNT NBR 10.004:2002 e considerado possível de ser disposto em aterro sanitário; a técnica da respirometria associado à caracterização pela Resolução CONAMA 375/06 - MMA torna o lodo da lagoa anaeróbia passível de aplicação agrícola e, o atendimento às exigências do Ministério da Agricultura permite buscar o registro, especificação e classificação do lodo como fertilizante, biofertilizante ou condicionador de solo. A remoção teve um custo de R$159,92/m3. Considerando as condições avaliadas nesta pesquisa, conclui-se que a utilização agrícola é a forma mais viável de disposição final de lodo de esgotos
Abstract: Concerns about the appropriate destination of sewage sludge made recycling a great perspective of alternative development in Brazil. The present study aims to evaluate the sludge from the anaerobic pond ETE Pedregulho / SP, operated by Sabesp, pumped and stored in bags, in relation to its quality, aiming to disposal. Three different bags were used and analyzed before, during and after pumping, it was noticed that during the time the permeability of the bags are not constant and there were changes in the characteristics of the sludge when in the bags. 614 m3 of sludge from the anaerobic pond were removed, with an improvement in the efficiency of ETE. The evoluation of volumetric shrinkage of the sludge in bags revealed the interference of rain in the volume of bags. There was an evaluation of liquid that percolated. The waste sludge was characterized as Class II A (non-hazardous, non-Inert) by the ABNT NBR 10.004:2002 and considered possible to be disposed in landfill; the technique of respirometry associated to the characterization by Resolução CONAMA 375/06 - MMA makes the sludge of the anaerobic pond be applied for agricultural purposes compliance with the requirements of the Ministry of Agriculture allows searching the record, specification and classification of the sludge as fertilizer, biofertilizer and soil conditioner. The removal had a cost of R$159,92 / m3. Considering the conditions evaluated in this study, it was concluded that agricultural use is the most viable form of disposal of sewage sludge
Mestrado
Saneamento e Ambiente
Mestre em Engenharia Civil
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Guaya, Caraguay Diana Elizabeth. "Evaluation of phosphate and ammonium removal and valorization from urban waste waters by impregnated metal hydrated oxides inorganic natural zeolites." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/461091.
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Phosphate and ammonium removal from waste water by adsorption using inorganic natural sorbents has been identified as a promising technology. The advantages of this methodology are associated with its availability and effective low cost.
Some natural and synthetic zeolite materials have been used for the individual phosphate and ammonium removal from aqueous solutions. The zeolites revealed high affinity for ammonium removal. However, some modifications stages are indispensable to enhance their oxyanionic sorption capacity to achieve high phosphate removal ratios. So, it is highly desirable to obtain a single sorbent for both cation and anion removal capacity from aqueous solutions. For this purpose, a natural zeolite with clinoptilolite as major mineral phase, was impregnated with metallic oxyhydroxides after conversion to the sodium form. As a result, hydrated metal oxides (HMO) of Al, Fe and Mn were immobilized on the zeolite surface structure.
The efficiency of aluminium, iron and manganese hydrated metal oxides was individually evaluated for the simultaneous phosphate and ammonium removal from aqueous solutions through batch and continuous mode assays using a granular natural zeolite sample. High selectivity was developed by modified zeolites towards these species in the presence of competing ions commonly present in urban and industrial waste waters. The regeneration assays demonstrated the limited use of modified zeolites in operational cycles as losses of the hydrated metal oxide along within the operation cycles will require re-impregnation stages. Then, an alternative option for final valorization of ammonium and phosphate is the use of the loaded zeolites as soil amendment for agricultural and forestry purposes or for environmental rehabilitation of degraded soils.
Therefore, a second approach could be to use the impregnated zeolites as nutrients carriers, improving their fertilizing properties by including potassium. For this purpose, powder samples of the natural zeolite in the potassium form were impregnated with the metallic oxyhydroxides and were enriched on nutrients (N,P,K) by using treated waters from the secondary effluent from "El Prat" Waste Water Treatment Plant using batch mode assays. The N-P-K release rates of the enriched zeolite samples were determined by column test using mixtures with three different types of agricultural soils.La recuperación de fosfato y amonio de agua residual mediante adsorción usando adsorbentes inorgánicos naturales ha sido identificado como una tecnología muy prometedora. Las ventajas de esta metodología se asocian a la amplia disponibilidad de adsorbentes de este tipo y su bajo costo. Algunos materiales zeolíticos naturales y sintéticos han sido usados para la adsorción individual de fosfato y amonio de soluciones acuosas. Las zeolitas revelan alta afinidad para la adsorción de amonio. Sin embargo, algunas etapas de modificación son indispensables para incrementar la capacidad de adsorción oxianiónica y conseguir altas tasas de adsorción de fosfato. Entonces, resulta conveniente obtener un solo adsorbente para la adsorción simultánea de cationes y aniones de soluciones acuosas. Con este propósito, una zeolita natural que contiene clinoptilolita como mayor fase mineralógica, se impregnó con hidróxidos metálicos después de su conversión a la forma sódica. Como resultado, los óxidos metálicos hidratados (HMO) de Al, Fe and Mn fueron inmovilizados en la superficie de la estructura zeolítica. La eficiencia de los óxidos metálicos hidratados de aluminio, hierro y manganeso fue evaluada individualmente para la adsorción simultánea de fosfatos y amonio de soluciones acuosas mediante ensayos por lotes y en continuo usando una zeolita en forma granular. Una alta selectividad fue demostrada por parte de las zeolitas modificadas respecto a la adsorción de estas especies en presencial de iones competidores comúnmente existentes en aguas residuales urbanas e industriales. Los ensayos de regeneración demostraron el uso limitado de las zeolitas modificadas en continuo así como también la pérdida de los óxidos metálicos hidratados con cada ciclo de operación puesto que requiere de una nueva impregnación en cada etapa. Entonces, una opción alternativa para la final valorización de fosfato y amonio es el uso de las zeolitas saturadas como material de mejoramiento de suelos con propósitos agrícolas o también para la rehabilitación de suelos degradados. Es así que se evidencia una oportunidad en el uso de zeolitas impregnadas como transportadores de nutrientes, de tal forma que mejoren las propiedades fertilizantes mediante la inclusión de potasio. Para cumplir con este objetivo, la zeolita natural en polvo se impregnaron con oxihidróxidos metálicos que fueron enriquecidos con nutrientes esenciales (N, P, K) usándolas para tratar aguas residuales provenientes de efluentes secundarios, específicamente de la Planta de Tratamiento de Agua Residual "El Prat" usando ensayos por lotes. Las tasas de liberación de N-P-K de las zeolitas enriquecidas se determinaron mediante pruebas en columna usándolas como aditivos en tres tipos diferentes de suelos agrícolas.
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Francisco, Eros Artur Bohac. "Fosfatos aluminosos do grupo da crandallita como fonte alternativa de fósforo para a cultura do arroz." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-20092006-171830/.
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O fósforo (P) tem sido um dos fatores mais limitantes da produção agrícola em solos de exploração recente, bem como nos solos há tempo utilizados e cuja fertilidade não é mantida. Tradicionalmente, o uso de fontes de P de elevada solubilidade tem auxiliado no aumento da fertilidade desses solos proporcionando acréscimos na produtividade das culturas. No entanto, o processo de fabricação desses fertilizantes requer o uso de rochas fosfáticas com baixa quantidade de impurezas metálicas como ferro e alumínio. Essa exigência tem levado as indústrias a descartarem quantidades elevadas de resíduo fosfático, no qual se encontram os minerais do grupo da crandallita. A busca de fontes alternativas de P para a produção agrícola encontra-se dentro do contexto de aproveitamento racional de recursos minerais existentes bem como de avançar no conhecimento de condições agronômicas que maximizem sua utilização pelas plantas. Para tanto, coletaram-se amostras do rejeito da mineração de depósitos fosfáticos de importância nacional (Catalão-GO, Juquiá-SP e Tapira-MG) contendo fosfatos aluminosos do grupo da crandallita, objetivando-se avaliar a capacidade desses minerais, após tratamento térmico, em disponibilizar P para plantas em solos sob condição de inundação e de pH próximo à neutralidade e determinar sua eficiência agronômica relativa em comparação à uma fonte padrão de P, relacionando-a com as suas características químicas e mineralógicas. O material coletado foi submetido ao tratamento térmico sob diferentes temperaturas para avaliar o efeito sobre a solubilidade e transformação morfológica. O material tratado foi: (i) misturado a amostras de terra com diferentes valores de pH para avaliar o comportamento de dissolução, (ii) submetido a teste de hidrólise em solução aquosa com valores de pH distintos e (iii) avaliado como fonte de P para as culturas do arroz-de-sequeiro e arroz inundado. De acordo com os resultados obtidos, concluiu-se que: (i) o tratamento térmico dos fosfatos aluminosos do grupo da crandallita com temperaturas ao redor de 500 ºC aumenta sua solubilidade em solução de citrato neutro de amônio e promove modificações na estrutura cristalina dos minerais, (ii) a liberação de P desses minerais é bastante reduzida em solução aquosa com valores de pH entre 4 e 8, (iii) a dissolução dos fosfatos aluminosos do grupo da crandallita calcinados em condição de solo é maior quando o valor de pH está próximo à neutralidade, comparado ao levemente ácido e (iv) que a adição dessas fontes de P ao solo promoveu resposta significativa na produção de matéria seca, na quantidade de P acumulado pela parte aérea das plantas e no rendimento de grãos de plantas de arroz-de-sequeiro e inundado, contudo não tão eficiente quanto a fonte padrão de P.Phosphorus (P) has been one of the most limiting factors for crop production in recent cultivated soils as well as in old cropped soils in which fertility is not maintained. Traditionally, the application of high solubility P sources has helped to raise soil fertility providing increase of crop yield. However, the manufacturing process of water-soluble P fertilizers requires the use of phosphate rocks with low quantity of metal impurities as iron and aluminum. This requirement has forced the fertilizer industry to discard great amounts of phosphate residue, in which the aluminous phosphates of the crandallite group can be found. Searching alternative P sources for crop production meets the context of rational use of existing mineral resources as well as move forward on the knowledge of agronomic conditions to maximize P uptake by plants. Therefore, samples of the mine residue from phosphate deposits of great relevance (Catalão-GO, Juquiá-SP e Tapira-MG) with aluminous phosphates of the crandallite group were collected and thermal treated, aiming to evaluate their ability to provide P to plants in soils under flooding condition and with pH around neutrality, to determine their relative agronomic effectiveness compared to a standard P source, and relate it with their chemical and mineralogical properties. The material collected was submitted to a thermal treatment under different temperatures to evaluate its effect on solubility and morphology. Treated material was (i) mixed to soil samples with different pH values to evaluate its dissolution, (ii) submitted to a hydrolysis test in aqueous solution with distinct pH values, and (iii) evaluated as a P source to upland rice and flooded rice. According to the obtained results, it was concluded that: (i) the thermal treatment of aluminous phosphates of the crandallite group with temperatures around 500 ºC increase its solubility in neutral ammonium citrate solution and cause alterations on the crystalline structure of minerals, (ii) P released from these mineral is very low in aqueous solution with pH ranging from 4 to 8, (iii) dissolution of aluminous phosphates of the crandallite group under soil conditions is higher when soil pH is around neutrality, compared to low acidity, and (iv) the addition of these P sources to soil significantly increased dry matter yield, P uptake by plants, and grain yield of upland rice and flooded rice, however not as much as for the standard P source.
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Aguiar, Rosa Helena 1952. "Utilização de esgotos tratados em reatores anaeróbios no cultivo de girassol." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256777.
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Orientadores: Durval Rodrigues de Paula Junior, Sylvio Luis HonórioTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola
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Resumo: O saneamento além de ser importante para a preservação dos recursos naturais representa uma ação preventiva eficaz para a melhoria do bem estar e da qualidade de vida da população nas questões relacionadas à saúde pública. A prática do uso de água residuária tem grandes vantagens, sobremaneira no aporte de nutrientes às plantas, fator que contribui para um crescimento mais rápido. Nesta pesquisa optou-se por utilizar o girassol (Helianthus annuus L.) ornamental que foi irrigado com águas residuárias. Objetivou-se a viabilidade do uso da área com disposição de esgoto tratado em reatores anaeróbios, por meio da avaliação do seu desenvolvimento e da sua produtividade durante três diferentes épocas de semeadura, visando reduzir os custos com nutrientes. Realizou-se esse experimento na área experimental da Faculdade de Engenharia Agrícola FEAGRI/UNICAMP, e foram avaliados cinco diferentes experimentos, dois deles por meio de reuso de efluentes de reatores - Upflow Anaerobic Sludge Blanket (UASB) e Reator Anaeróbio Compartimentado (RAC) associado a filtros anaeróbios, enquanto que os outros foram constituídos de: Testemunha, sem qualquer tipo de irrigação; com irrigação, utilizando somente água tratada, e com água tratada em área fertilizada com NPK. Foram avaliados respostas fitomorfológicas da cultura, assim como: diâmetro dos caules (DC); altura das plantas (HP); diâmetro dos capítulos (DCp); massa seca dos caules e das folhas (MS); número de folhas (NF) e sua produtividade. Os sistemas modulares (UASB e RAC) de tratamento de esgoto apresentaram um bom desempenho, com elevados valores de remoção de SSed (98,72; 98,36%), e DQO (72,37; 75,79%) não havendo diferença significativa entre os sistemas de tratamento. Constatou-se também que os canteiros com tratamentos com reuso de efluentes promoveram alteração na fertilidade do solo, com o aumento nos valores de saturação por bases (V%) na profundidade de 0 - 20 cm. Analisando os efeitos sobre a cultura nos três plantios, verificou-se um melhor desenvolvimento nos canteiros com os tratamentos do efluente, quando comparado com os demais tratamentos principalmente no segundo e terceiro plantio. Sistemas modulares de tratamento de esgotos associados ao reuso agrícola de seus efluentes podem agregar valores à produção agrícola, podendo ser utilizado inclusive no período de chuvas e em locais onde há escassez de água pluvial
Abstract: Sanitation is also important for the preservation of natural resources, represents an effective preventive action to improve the well-being and quality of life of the population on issues related to public health. The practice of using wastewater has great advantages, particularly in the supply of nutrients to plants, factor that contributes to a faster growth. In this research we decided to use the Sunflower (Helianthus annuus L.) ornamental that was irrigated with wastewater. The viability of the use of the area with provision of treated sewage in anaerobic reactors, by assessing their development and their productivity during three different periods of sowing to reduce costs with nutrients. This research was developed in the experimental area of the Faculty of agricultural engineering FEAGRI/UNICAMP, and evaluated five different treatments, two of them by means of Upflow Anaerobic Sludge Blanket reactors (UASB) and Anaerobic Reactor Chambered (ARC) associated with anaerobic filters, while the others were made up of: witness, without any kind of irrigation; with irrigation, using only treated water and treated water in the area fertilized with NPK. Fitomorfológicas culture responses were evaluated as: diameter of stems (DS); plant height (HP); diameter of the chapters (DCp); dry mass of stems and leaves (DM); number of leaves (NF) and your productivity. Modular systems (UASB and ARC) sewage treatment showed a good performance, with high values of removing SSed (98.72; 98.36), and COD (72.37; 75.79) with no significant difference between the treatment systems. It was noted also that the flower beds with wastewater reuse treatments promoted change in the fertility of the soil, with the increase in base saturation values (V%) at the depth of 0-20 cm. Analyzing the effects on culture in three plantations, there was a better development in the flower beds with the effluent treatments, when compared with the other treatments mainly in the second and third planting. Modular wastewater treatment system associated with the agricultural reuse of wastewater can add value to their agricultural production, and can be used throughout the year even in places where there is scarcity of rainwater
Doutorado
Agua e Solo
Doutor em Engenharia Agrícola
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Costa, Antonio Marcos Tubiana de. "Codigestão anaeróbia de resíduos bovinos e suínos: caracterização química e produção de biofertilizante para uso em cultura de milho." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1116.
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Ao abordar o tema contaminação ambiental, logo se recorda a quantidade de resíduos domésticos e urbanos, que são gerados nas cidades e metrópoles, os quais muitas vezes não recebem nenhum tipo de tratamento. Porém, problemas de contaminação ambiental também estão vinculados à agricultura, onde são gerados resíduos orgânicos com elevados potenciais poluidores. Dessa forma, o projeto objetivou estudar o processo de codigestão anaeróbia de dejetos bovinos e suínos oriundos de sistemas de produção de suínos e atividade pecuária leiteira, como alternativa para tratamento destes tipos de matrizes, além de investigar a eficiência do biofertilizante produzido a partir das matrizes de resíduos em cultura de milho. Para isso, se coletaram amostras de dejetos de bovinos e suínos para caracterização e posterior utilização nos ensaios com tratamentos diferentes. Na sequência se fez a preparação das amostras para os ensaios utilizando-se de inoculos diferenciados (in natura, inoculo da rede de saneamento básico e inoculo isolado de dejeto bovino) com o propósito de avaliar a degradação dos dejetos via codigestão anaeróbia. Em cada ensaio citado se fizeram vinte tratamentos, via planejamento fatorial 2³, com seis pontos centrais, sendo as variáveis de entrada: tempo, fração de sólidos e razão de mistura; e as variáveis respostas (dependentes): pH, razão AV/AL, umidade, série de sólidos, razão SV/ST, redução de sólidos totais, DQO, redução de DQO, nitrogênio total, fósforo e potássio. Fez-se depois o estudo cinético do processo, se utilizando do ensaio in natura com proporção de mistura de 75% em dejeto suíno e 25% em dejeto bovino, com fração de sólidos de 8,9%, mediante Teste de Tukey. Após a estabilização da biomassa utilizada, fez-se a aplicação do biofertilizante em cultura de milho, comparando-se com fertilizante comercial (ureia), verificando-se o crescimento e desenvolvimento desta cultura. No planejamento fatorial se concluiu mediante análise de Tukey e considerando a importância de cada variável resposta que o ensaio in natura apresentou as melhores condições operacionais, pois se teve o maior número de variáveis respostas sendo consideradas satisfatórias, como razão AV/AL, razão SV/ST e redução da DQO. Observou-se durante o estudo cinético que a biomassa apresentou estabilização próxima aos vinte dias de tratamento, indicando a degradação orgânica dos dejetos em codigestão e produção de biofertilizante, o qual é mais estável e menos poluente ao ambiente, sendo utilizado como opção no processo de fertilização de culturas agrícolas como o milho. No que diz respeito à utilização do biofertilizante (40 kg.ha-1), notou-se semelhança deste se comparado à ureia (40 kg.ha-1) para o cultivo de milho, podendo ser uma alternativa interessante de destinação dos dejetos, diminuindo a poluição ambiental causada pelo manejo inadequado.When discussing environmental contamination, just remember the amount of domestic and urban waste that are generated in towns and cities, which often do not receive any treatment. However, problems of environmental contamination are linked to agriculture, where organic waste with high potential polluters is generated. This way, the project had the objective of studying the anaerobic codigestion process of cattle and pig waste from the swine production systems and dairy farming activity, as an alternative to the treatment of these kinds of matrices, as well as to investigate the efficiency of biofertilizer matrices produced from the waste in cultured maize. For this, samples of manure from cattle and pigs were collected for characterization and subsequent use in the tests with different treatments. Then, the preparation of samples for the tests using the different inocula were made (in natura, inoculum of sanitation and inoculum isolated from bovine manure), in order to evaluate the degradation of waste via anaerobic codigestão. In each test mentioned twenty treatments were made, via 2³ factorial design with six central points, where the input variables: time, fraction of solids and mixing ratio; and the response variables (dependent): pH, ratio AV/AL, moisture, solids, ratio SV/ST, reduction of total solids, COD, reduction of COD, total nitrogen, phosphorus and potassium. It was made after the kinetic study of the process, using the test in natura mix ratio of 75% in swine manure and 25% in cattle manure with solid fraction of 8.9% by the Tukey test. After stabilization of the biomass used, there was the application of biofertilizers in crop maize compared with commercial fertilizer (urea), verifying the growth and development of this culture. In factorial design was completed by Tukey analysis and considering the importance of each variable response that the test in natura presented the best operating conditions, because it had the largest number of variable responses being considered satisfactory ratio as AV / AL, ratio SV / ST and COD reduction. It was observed during the kinetic study that biomass showed stabilization next to twenty days of treatment, indicating the degradation of organic waste in codigestão and biofertilizer production, which is more stable and less polluting to the environment, being used as an option in process fertilization of agricultural crops such as maize. Regarding the use of biofertilizers (40 kg.ha-1), this similarity was noted compared to urea (40 kg.ha-1) for the cultivation of maize and it may be an interesting alternative for allocation of waste, reducing environmental pollution caused by improper handling.
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Adler, Anneli. "Accumulation of elements in Salix and other species used in vegetation filters with focus on wood fuel quality /." Uppsala : Dept. of Crop Production Ecology, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200706.pdf.
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Pettersson, Hanna, and Elin Törnvall. "Efterbehandling av biogödsel : Ett försök med avskiljning och uppsamling av kväve och vatten genom ammoniakstripping i en efterhygieniseringsprocess." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-38018.
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During this master thesis, the possibility of ammonia removal from digestate in combination with after hygienization has been investigated. The aim of the work was to see how much ammonia that could be removed but also the properties of other process parameters such as TS/VS content, pH and alkalinity of the digestate. It was also of interest to study the energy balances for a process that combines ammonia stripping with after hygienization. The purpose of hygienization in a biogas plant is to kill pathogens. To study ammonia stripping combined with after hygienization, a prototype of an ammonia stripper was built in a laboratory. The digestate was heated to the hygienization temperature of 70 °C and air was led through with the help of a peristaltic pump by the end of the system. Condensate was trapped in a bottle by cooling the tube and the gases were brought to another bottle containing 1 M sulfuric acid. Ammonia and sulfuric acid reacted and formed ammonium sulfate. The process was also tested with closed system using vacuum to decrease the boiling point and thereby create more condensate. The results from the experiments showed that with an air stripping process most of the ammonium was trapped in the sulfuric acid while with a vacuum process more ammonium was trapped in the condensate. The most important parameters to achieve a good ammonia removal were air flow and time. With the vacuum system, more condensate was removed. The removal of condensate could make it possible to recirculate process fluid from the stripping process and thereby save energy in the centrifugation part which is used to create a solid part of the bio digestate. It was concluded from the experiments that air stripping is more effective when it comes to ammonium recovery. The process could be improved by using higher air flow which could decrease the time to less than one hour, which is the desired hygienization time. However, it is desired to keep the pump flow as low as possible since it is energy consuming. A chemical increase of the pH would also be of interest to try since previous tests showed a strong correlation between high pH-value and good ammonia stripping. More tests overall are of interest to ensure a reliable result. Still, the combination of after-hygienization and ammonia stripping would contribute to a better environment and a sustainable agriculture with a natural and nutritious digestate.
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Karunarathna, Mudugamuwe Hewawasam Jayan Savinda. "Photochemistry of iron(III) with carboxylate-containing polysaccharides for sustainable materials." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1586468303760847.
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Chen-Yue and 陳玥. "Heavy metals uptake of paddy rice on serpentine soils with different fertilizer treatments." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/12162590572668287305.
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碩士國立屏東科技大學
環境工程與科學系所
101
Serpentinitic soils are high in Cr and Ni which may have the potential risk to crop growth and eco-environment, and groundwater contamination. This study used 2 serpentinitic soil samples (WR and TA) from eastern Taiwan to cultivate paddy rice by pot experiment amended with different fertilizer treatments in the open field. All treatments included control (blank), 120-60-60 kg/ha (NH4)2SO4 1.47 g, CaHPO4 0.17 g, and KCl 0.14 g per pot), 120-90-60 kg/ha ((NH4)2SO4 1.47 g, CaHPO4 0.26 g, KCl 0.14 g per pot), and 120-120-60 kg/ha ((NH4)2SO4 1.47 g, CaHPO4 0.35 g, KCl 0.14 g per pot). The experimental results indicated that WR and TA soils pH gradually decreased during rice growth, due to acidity of the chemical fertilizer addition. Addititonally, no difference was found in Cr heavy metal level in the soil solution. Fe and Mn concentrations were higher in the TA soil than in the WR soil. Iron plaque on rice roots, in the different fertilizer treatments the order of Fe, Mn, Cr, Ni and Co accumulated concentration was: Fe> Mn> Ni> Co> Cr. The results show that Fe, Cr, Ni, Co were concentrated in the root of rice, and Mn concentrations (757.5 mg/kg) in the stalk part was higher than in the root. The concentrations of all metals in the rice tissues were higher than those in general plants, and thus the Cr and Ni concentrations in the rice were up to 1.16 mg/kg and 8.57 mg/kg.
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Jing-Han, Wu, and 吳景翰. "Soluble heavy metal and rice uptake from a serpentine soil with different fertilizer treatments." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/21455469282064113522.
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碩士國立屏東科技大學
環境工程與科學系所
97
Serpentinitic soils are concentrated in the eastern areas of Taiwan, which are rich in heavy metal such as Cr, Ni, and Co with potential risk to crop growth and the eco-environment. This study used a serpentinitic Vertisol for the pot experiment by paddy rice (Kaohsiung No. 45) amended with different fertilizer treatments in the open field. All treatments were: unfertilized control (Blank), full recommended dose of chemical fertilizer (CF), half recommended dose of chemical fertilizer + 2.5 ton ha-1 oilseed compost (1/2 CF + 2.5 OC), 5.0 ton ha-1 oilseed compost (5.0 OC), and 10 ton ha-1 oilseed compost (10 OC), respectively. Six single extractions, including H2O, HCl, NaNO3, CaCl2, EDTA, and DTPA, were performed for the treated soils. The experimental results indicated that Cr and Ni were concentrated in the root of rice, and Mn was in the stalk parts. The concentration of all metals in the rice tissues were higher than those in general plants (1~2 mg/kg), and thus the Cr and Ni levels in the brown rice were up to 4.48 mg/kg and 6.71 mg/kg. However, the Cr and Ni levels in this study were within the normal ranges of rice grain in Taiwan. The amounts of heavy metal using the single extraction were always higher in the soils with fertilizer treatments than the initial soils, suggesting the solubility of heavy metal increased with the planting rice in the soils. In the oilseed compost treatments, the metal contents in soil and plant were high, due to the strong acidity of the compost in reducing soil pH. Additionally, no difference was found in heavy metal levels of soil solution between all treatments.
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Hsu, Chih-Cheng, and 許志誠. "The Nitrogen Balance of Different Fertilizer Treatments in a Long-Term Corn-Rice Rotation Soil System for Six Years." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/07097180091890058682.
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碩士國立臺灣大學
農業化學研究所
92
Corn and rice plants are commonly for staple food production .To supply optimum amount of effective nitrogen through fertilizer during the growth period of the crop plants is very important. This study deal with an field experiment of sixth year of a long-term corn-rice rotation, which aimed at studing the nitrogen blance of differently fertilized treatment in corn-rice rotation. The field experiment was carried out at the Taiwan Agriculture Research Institute. The spring crop was rice plant and the autumn crop was corn plant. The application rates of fertilizer were 140-80-80（N-P2O5-K2O）kg ha-1and 120-60-60（N-P2O5-K2O）kg ha-1, for corn and rice, respectively. There were seven treatments: 1. check plot (CK); 2. chemical nitrogen fertilizer plot (Chem N); 3. compost plot (Comp); 4. compost with one third of nitrogen as chemical fertilizer plot (Comp+1/3 N); 5. compost with two thirds of nitrogen as chemical fertilizer plot (Comp+2/3 N); 6. green manure with one third of nitrogen as chemical fertilizer plot (GM+1/3 N); 7. peat with one third of nitrogen as chemical fertilizer plot (Peat+1/3 N). The same amounts of P2O5 and K2O as afore muctiond, in form of superphosphate and potassium chloride, respectively, were applied to treatments except CK plot. All treatments were replicated four times and arranged in ramdonized complete block design. The block size was 20 x 6 m2. Soil was sampled at different growth stages of corn plant and rice plant, respectively. Soils sampled from three spots of each block were mixed, air dried, grounded to pan 10 meshsieve. The concentrations of total nitrogen, nitrate nitrogen, and ammonium nitrogen were determined. The soil analysis have shown that the concentration of inorganic nitrogen were lower in CK and Chem N plots. The grain yield was the lowest in CK plot. The concentration of higher inorganic nitrogen in the soils had resulted in higher grain yield. The Chem N plot provided more inorganic nitrogen; then in order the Comp plot, Comp+1/3 N plot, Comp+2/3 N plot, GM+1/3 N plot, and Peat+1/3 N plot at the early growth period of plants. The organic fertilizer decomposed slowly, and provided inorganic nitrogen to the plants steadily for a longer period. Thus the treatment Comp+2/3 N plot had the highest corn and rice grain yield. The treatment Comp+2/3 N plot provided inorganic nitrogen in reasonable pattern during plant growth stage and thus resulted in increased grain yield. Expecially, the organic fertilizer with 2/3 chemical fertilizer-N could provide inorganic nitrogen reasonably during the whole growth period of plants. Reduced chemical fertilizer application rate could decrease pollution of environment.
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vanAkker, Lara. "The effects of fertilizer treatments on the resin canal defenses of spruce and incidence of attack by the white pine weevil, Pissodes strobi." Thesis, 2002. http://hdl.handle.net/2429/13331.
Full textAbstract:
The white pine weevil, Pissodes strobi (Peck), is a serious pest of regenerating
spruce (Picea spp.) in British Columbia. On the coast, damage by this weevil results in
such severe stem defects and growth losses in Sitka spruce (Picea sitchensis), that
planting this species is not currently recommended in high weevil hazard areas. In the
interior of the province, hundreds of millions of interior spruce seedlings (Picea glauca x
englemanii) are currently in weevil susceptible age classes. Past attempts to control this
weevil have been unsuccessful. Current research is focused on identifying trees with
genetic resistance to the weevil and identifying the defense traits which give rise to this
resistance. While weevil resistance has been shown to be heritable, environmental
factors such as plant nutrient status may alter the expression of defense traits. My goal
was to determine the effects of fertilization treatments on the resin canal defenses in
spruce and incidence of weevil attack.
Fertilizer effects on tree size variables were measured to provide baselines for
the comparison of treatment groups and to facilitate discussion on the effects of
variation in tree size due to fertilizer treatment, on incidence of weevil attack. The
constitutive resin canal systems of Sitka and interior spruce maintained under several
fertilizer regimes were compared by histological examination of leader cross sections.
Traumatic response intensity was compared utilizing mechanical wounding to stimulate
a traumatic response, followed by histological examination of cross sections through the
wounded stem. Incidence of weevil attack in response to fertilizer treatments was
studied in a caging experiment in which weevils were given a choice between trees from
different fertilizer treatments, and in a variably fertilized plantation, naturally infested
with weevils.
The effects of fertilization on constitutive resin canal variables were influenced by
spruce genotype, but not resistance status. In general, there was a dilution in cortical
resin canal defenses in response to fertilization, which included a decrease in resin
canal density and an increase in depth and distance between inner resin canals. These
effects corresponded with, and may have been due to increasing bark thickness in
response to fertilization. In severely nutrient stressed trees, fertilization may also
improve the ability of trees to produce a traumatic response. Fertilization increased the
incidence of weevil attack in both Sitka and interior spruce. In interior spruce, more than
twice as many trees were attacked in the intense fertilizer treatments than in the
unfertilized control groups. The observed increase in weevil attack in the more intense
fertilizer treatments may be attributed to increased host vigor, resulting in an increase in
resources available for weevil feeding and oviposition and a dilution of cortical resin
canals. It is recommended that further studies be undertaken to investigate the effects
of fertilization on other factors such as resin composition and flow.
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"Bioestimulant and fertilizers associated at the treatment corn and soybean seeds." Tese, BIBLIOTECA CENTRAL DA UFLA, 2006. http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=219.
Full text
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Vertonha, Maria Thais. "Valorization of leached waters through conversion in liquid fertilizers." Master's thesis, 2018. http://hdl.handle.net/10198/21034.
Full textAbstract:
Dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáAn unprecedented demographic explosion occurred in the last decades at a global level. The negative impacts of this event stand out, affecting the social, economic and mainly environmental spheres. In the environmental aspect, an important consequence is the growing production of solid wastes, due partially to the population increase. However, the development of effective technologies for the treatment of these wastes did not accompany such growth, and currently the most used method for this is landfill disposal. Even with the possibility of alternatives, the use of landfills for the disposal of solid wastes will be necessary over a long period, with the inevitable consequence of the generation of leachate streams. The objective of this work is the development, design and implementation of processes for physicochemical conversion of leachate liquid effluents from a composting process in liquid fertilizers with a standardized and reproducible composition. The leachate sample was collected in February 2019 from the slurry storage tank of the company “Resíduos do Nordeste”, EIM (Urjais, Mirandela, Portugal). The stream is produced and recovered from a composting line from a mechanical and biological waste treatment plant. From this original sample, three additional materials were obtained: a filtered sample for the removal of the solid fraction (Filtro 03/04), two concentrated samples by simple distillation, with two concentration levels in volume basis: 1,19x and 1,85x in relation to the original leachate sample. The four samples (the original leachate and the three processed samples) were submitted to a sequence of analyzes, in order to compare its composition and properties with the current Portuguese and European legislation specifications for liquid fertilizers. The selected characterization parameters were: Total Organic Carbon (TOC), pH, Conductivity, Percentage of Dry Matter, Density, and Heavy Metals, Phosphorus, Potassium and Nitrogen contents. Adsorption tests were performed with the Filter 03/04 sample, with two adsorbents of different origin, the first produced from an organic compound, resulting from a centralized composting process, obtained from the same landfill that provided the Original sample. The second adsorbent tested is activated clays, originating from four different deposits in Kazakhstan. After treatment with the adsorbents, the same analyzes were performed previously, aiming to evaluate the efficiency of the adsorbents. The characterization results were then used to verify the framework for later use of the original leachate and/or the processed samples as liquid organomineral fertilizers, and to assess the specific needs of composition tuning for the non-processed leachate sample. A concentration process for the original sample of 1,19x (v/v) has been determined to allow the reaching of at least 3% TOC, a content legally required. Additionally, treatment is required for the removal of nickel and chromium from the samples. The metals zinc, copper, cadmium and lead have been quantified and are within the limits specified in the Regulation of the European Parliament and of the Council (2019). A flowchart for the proper treatment of this leachate was proposed, with the intention of using it as liquid organomineral fertilizer.
Uma explosão demográfica sem precedentes ocorreu nas últimas décadas a nível global. Destacam-se os impactos negativos deste evento, afetando as esferas social, econômica e principalmente ambiental. No aspeto ambiental, uma consequência importante é a crescente produção de resíduos sólidos, em parte devido ao aumento populacional. No entanto, o desenvolvimento de tecnologias eficazes para o tratamento desses resíduos não acompanhou esse crescimento, e atualmente o método mais utilizado para isso é o descarte em aterros sanitários. Mesmo com a possibilidade de alternativas, o uso de aterros sanitários para a disposição de resíduos sólidos será necessário por um longo período, com a inevitável consequência da geração de caudais de chorume. O objetivo deste trabalho é o desenvolvimento, proposta e implementação de processos de conversão físico-química de efluentes líquidos lixiviados, de um processo de compostagem, em fertilizantes líquidos com uma composição padronizada e reprodutível. A amostra de lixiviados foi coletada em fevereiro de 2019 a partir do tanque de armazenamento de chorume da empresa “Resíduos do Nordeste”, EIM (Urjais, Mirandela, Portugal). O fluxo é produzido e recuperado de uma linha de compostagem de uma estação de tratamento de resíduos mecânica e biológica. Desta amostra original, três materiais adicionais foram obtidos: uma amostra filtrada para a remoção da fração sólida (Filtro 03/04), duas amostras concentradas por destilação simples, com dois níveis de concentração em base volumétrica: 1,19x e 1,85x em relação a amostra original. As quatro amostras (o lixiviado original e as três amostras processadas) foram submetidas a uma sequência de análises, de modo a comparar a sua composição e propriedades com as atuais especificações da legislação portuguesa e europeia para fertilizantes líquidos. Os parâmetros de caracterização selecionados foram: teor de carbono orgânico total (TOC), pH, condutividade elétrica, percentagem de matéria seca, densidade e metais pesados, fósforo, potássio e nitrogênio. Foram realizados testes de adsorção com a amostra Filtro 03/04, com dois adsorventes de origem diferente, o primeiro produzido a partir de um composto orgânico, resultante de um processo de compostagem centralizada, obtido do mesmo aterro sanitário que forneceu a amostra Original. O segundo adsorvente testado, são as argilas ativadas, originárias de quatro depósitos diferentes do Cazaquistão. Após o tratamento com os adsorventes foram realizadas as mesmas análises feitas anteriormente, com o objetivo de avaliar a eficiência dos adsorventes. Os resultados da caracterização foram então utilizados para verificar a estrutura para posterior utilização do lixiviado original e/ou as amostras processadas como fertilizantes organominerais líquidos, e para avaliar as necessidades específicas de ajuste da composição. Um processo de concentração para a amostra original de 1,19x (v/v) foi determinado para permitir o alcance de pelo menos 3% de TOC, um conteúdo legalmente requerido no Regulamento do Parlamento Europeu e do Concelho (2019). Além disso, é necessário um tratamento para a remoção de níquel e cromio das amostras. Os metais zinco, cobre, cádmio e chumbo foram quantificados e estão dentro dos limites especificados no Regulamento do Parlamento Europeu e do Conselho (2019). Um fluxograma para o tratamento adequado desse lixiviado foi proposto, com o intuito de utilizá-lo como fertilizante organomineral líquido.
This work was carried out under the scope of Project VALORCOMP, funded by FEDER through Programme INTERREG V-A Spain − Portugal (POCTEP) 2014–2020. Finally, to all who have somehow been part of this period and collaborated to carry out this work, I will be eternally grateful.
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Chen, Wen-pin, and 陳文彬. "The development of a rapid organic fertilizer apparatus for poultry''s excrement treatment process." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/39230880269504577948.
Full textAbstract:
碩士國立高雄第一科技大學
機械與自動化工程研究所
100
The excrement treatment is a deficient process of livestock automation. In this study we newly design and fabricate a rapid composting equipment of organic fertilizer for poultry''s excrement treatment. The price of import compost equipment is very expensive, and the maintenance is also problematic. The proposed design improves the above-mentioned problems. This equipment can deal with excrement amount of 120,000 chickens and finish fermenting on the same day. It also solves the problems of flies, stench, pollution of water, piling up the area, and infectious disease of H5N1~Nx, etc. The closed type tank is to get rid of flies and stench. The ferment time is shortened from several teens’ days to 24 hours. This proposed system can cut off the pile area, too. A heating blower was designed to dry and agitating blades were adopted to ferment the compost temperature. This study aims at designing and constructing the system, including the tank and agitation mechanism, stirred blades, and heating blower. The optimum processing temperature, air supply rate, and excrement moisture content in the fermentation process conditions are explored. Sequence experiments were carried out to find the best conditions within 24 hours to convert high-quality organic fertilizer. In addition to the contribution of the mechanism design, we also have a considerable contribution to the farming environment, health, and farmers’ income. However, the power consumption is up to 100 kw-hr. We redesign our process to cut down power consumption to 80 kw-hr, Our further study is that the power source can be replaced by using renewable energy for environment concerns.
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Adadzi, Patrick Cudjoe. "Deep row trenching of pit latrine and waste water treatment works sludge : water and nutrient fluxes in forest plantations." Thesis, 2012. http://hdl.handle.net/10413/10034.
Full textAbstract:
The deep row trenching of ventilated improved pit-latrine (VIP) and waste water treatment
works (WWTW) sludge is a unique alternative cost effective land application method that will
prevent odour and health problems and may permit higher application rates than surface
application. The goal of this research is to assess the environmental consequences of employing
deep row incorporation of VIP and WWTW sludge to forest plantation lands for the production
of Eucalyptus dunnii. The objectives are to monitor, define and quantify the fluxes of nutrients
(nitrate and phosphorus) from the buried sludge to the surrounding soils, groundwater and
surface water. The WWTW study was conducted on a forestry plantation located near the
Shafton Karkloof Falls, about 10 km from Howick in the KwaZulu-Natal province of South
Africa. The land for the research is owned by SAPPI, a timber plantation company. The
trenching was done with stockpiled secondary sludge from Umgeni WWTW in Howick. VIP
sludge trenching was done at the Umlazi E-ponds site in Durban owned by EThekwini
Municipality. This site was formally used as a wastewater treatment plant sludge drying bed. The
treatment works comprised three oxidation ponds and was operated until 1999, when it was
decommissioned after a heavy flood, resulting in damage to the oxidation ponds. The sites were
instrumented with wetting front detectors, piezometers and boreholes for collection and analysis
of leachate from which were determined subsurface loss of nitrogen and phosphorus. Soil water
status and groundwater levels were also monitored. Simulation of the process of water, nitrate
and phosphorus transport was performed in order to aid the development of the sustainable
management methodologies for land application and the trenching of VIP/WWTW sludge. The
study focuses on the entrenched sludge to determine the concentration of pollutants, monitorchanges in concentration over time and to monitor the movement of solutes and any change
taking place in the surrounding soil water and groundwater. The results contribute to the
development of guidelines and protocols for VIP/WWTW sludge handling and trenching in
South Africa. It was demonstrated that the nutrient migration processes can be approximated
with the conceptual simplifications of the inputs to the model based on field evidence, soil
survey data and applicable literature. In the study, it was found that high concentrations of
nutrients were evident in the water infiltrating into and through the sludge in all trench types.
The nitrate concentration median values in the trenches were 234mg/l and 36mg/l for SAPPI and Umlazi respectively, while the recorded median value for phosphorus was 1.0mg/l and 3.5mg/l
for SAPPI and Umlazi respectively. However the effect of vertical seepage of nutrients, into the
deep aquifer in fractured rock has not been observed in the deep borehole with the nitrate
concentration median values at 5mg/l and 0.6mg/l for SAPPI and Umlazi respectively, while the
phosphorus concentration median values were 0.03mg/l and 0.15mg/l for SAPPI and Umlazi
sites respectively. The study revealed significant differences between the sandy alluvial site at Umlazi and the shale
dolorite site at the SAPPI forests. Where an unsaturated zone below the entrenched sludge
existed at the Umlazi site, nutrient transport was retarded, whereas in the shales of the SAPPI
site, preferential delivery flowpaths transported high concentrations of nutrients rapidly from the
entrenched sludge to the base of the hillslope. These mechanisms needed to be treated differently
in the simulation exercise.Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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(6623615), Jesse A. Haarmann. "The Effect of Herbicide Respray Treatments and Timings on Regrowth of Four Weed Species." Thesis, 2019.
Find full textAbstract:
Control of weeds that have survived a postemergence (POST) herbicide often need to be controlled in order to prevent seed production and interference with crops. The most efficacious herbicides and timings used for respray applications has not been determined in many problematic weed species. Previous research has demonstrated that weeds clipped to simulate a failed herbicide application responded differently to herbicide applications to regrowth based on herbicide used and weed species. Other research is conflicting as to the optimum timing of an herbicide respray application with various herbicides. Gaining a better understanding of how to maximize respray herbicide performance will help growers and land managers to preserve crop yield and prevent weed seed production in the event of POST contact herbicide failure. The objectives of this research were to determine the optimum respray herbicide and timing combinations for control of four problematic weed species in the midwestern United States that have survived an application of either glufosinate or fomesafen: waterhemp [Amaranthus tuberculatus (Moq.) J. D. Sauer], Palmer amaranth (Amaranthus palmeri S. Watts), giant ragweed (Ambrosia trifida L.), and horseweed (Erigeron canadensis L). Through a series of field and greenhouse experiments we determined that respray herbicide, respray application timing, initial herbicide, and level of injury from the initial application influence efficacy of the respray herbicide in a species-specific manner. Waterhemp regrowth following a failed glufosinate application was controlled most effectively by applying glufosinate or fomesafen 7 to 11 days after initial treatment. When following fomesafen, applications of 2,4-D 3-7 days after initial treatment or glufosinate 7 to11 days after initial treatment were most effective. Control of Palmer amaranth regrowth following either initial herbicide is best achieved with respray applications of glufosinate, fomesafen, or 2,4-D applied no later than 7 days after initial treatment. The best strategy to control giant ragweed regrowth following a failed fomesafen applications is to apply 2,4-D, dicamba, fomesafen, or glufosinate at any timing between 3 and 11 days after initial treatment. Efficacy of the respray glufosinate application was maximized when applied 11 days after the initial application rather than 3 days after initial application. Horseweed regrowth was best controlled by 2,4-D, dicamba, or glufosinate applied at any timing between 3 and 11 days after the initial application. Where injury from the initial herbicide application is high, there were fewer differences among herbicide treatments and treatment timings. A greenhouse bioassay revealed that as waterhemp injury from an initial glufosinate application increases, control with a respray herbicide also increases. Therefore, complete control of weed regrowth is achieved more easily with increasing injury from the initial application. This research suggests that timing of herbicide respray applications is more urgent than previously thought, so scouting must be done within days of a contact herbicide application to ensure adequate control.
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Sibiko, Kenneth Waluse. "Economics of Weather Index-Based Insurance: Analysis of Smallholder Farmers' Preferences and the Impact of Insurance on Productivity in Kenya." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-002B-7CC0-2.
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Sousa, Catarina Viegas de. "BIOREMEDIATION OF AGRO-INDUSTRIAL EFFLUENTS MEDIATED BY MICROALGAE." Doctoral thesis, 2022. http://hdl.handle.net/10362/134504.
Full textAbstract:
Every year, large amounts of agro-industrial effluents are produced all over the world and its sustainable management is still a technological challenge. This thesis addresses the remediation of four agro-industrial effluents (aquaculture, cattle, swine, and poultry) and an industrial effluent (landfill leachate) by treatment with biomass ash and microalgae. The pre-treatment with biomass ash allowed the partial precipitation of total solids, reduction of the turbidity and microbial load of the effluents, resulting in a partially treated effluent and a precipitate rich in mineral and organic components. The aqueous effluents were treated in batch and semi-continuous modes with the microalgae Chlorella vulgaris (Cv), Auxenochlorella protothecoides (Ap), Tetradesmus obliquus (To), Isochrysis galbana (Ig), Microchloropsis salina (Ms), and Spirulina major (Sm). Maximum biomass yields were reached for microalgae Cv (193.6 to 879.8 mg L-1 day-1) and To (236.7 to 811.7 mg L-1 day-1) in agro-industrial effluents. The remediation of effluents allowed reaching discharge values mandatory by law for total nitrogen and total phosphorus, COD, BOD5, and total solids. The precipitate obtained in the pre-treatment of the effluents and the algal biomass showed positive effects as biostimulants for the germination of watercress (Nasturtium officinale) and wheat (Triticum aestivum) seeds. The microalgae biomass was characterised and evaluated as a food supplement for mussels (Mytilus edulis) for 45 days, with changes in the contents of lipids, carbohydrates, and ash of the mussels being observed. The torrefaction of algae biomass and its mixtures with lignocellulosic biomass made it possible to obtain biochars with potential for energy recovery, use as biostimulants for seed germination, or as adsorbents for cationic pigments. The work carried out allowed to demonstrate the feasibility of treating the studied effluents by chemical precipitation and bioremediation with microalgae and to suggest different ways of valuing the solid by-products generated.Anualmente, grandes quantidades de efluentes agroindustriais são produzidas em todo o mundo e a sua gestão sustentável constitui, ainda, um desafio tecnológico. Esta tese aborda a remediação de quatro efluentes agroindustriais (aquacultura, gado bovino, gado suíno e aviário) e um efluente industrial (lixiviado de aterro) por tratamento com cinzas de biomassa e microalgas. O pré-tratamento com cinzas de biomassa permitiu provocar uma precipitação parcial dos sólidos totais, reduzir a turvação e a carga microbiana dos efluentes, originando um efluente parcialmente tratado e um precipitado rico em componentes minerais e orgânicos. Os efluentes aquosos foram tratados em modos descontínuo e semi-contínuo com as microalgas Chlorella vulgaris (Cv), Auxenochlorella protothecoides (Ap), Tetradesmus obliquus (To), Isochrysis galbana (Ig), Microchloropsis salina (Ms) e Spirulina major (Sm). Foram atingidas produtividades máximas de biomassa para as microalgas Cv de 193,6 a 879,8 mg L-1 dia-1 e To de 236,7 a 811,7 mg L-1 dia-1 em efluentes agroindustriais. A remediação dos efluentes permitiu atingir valores de descarga obrigatórios por lei para azoto total, fósforo total, CQO, CBO5 e sólidos totais. O precipitado obtido no pré-tratamento dos efluentes e a biomassa algal apresentaram efeitos positivos como bioestimulantes da germinação de sementes de agrião (Nasturtium officinale) e de trigo (Triticum aestivum). A biomassa microalgal foi caracterizada e avaliada como suplemento alimentar de mexilhões (Mytilus edulis) durante 45 dias, tendo-se observado alterações nos teores de lípidos, hidratos de carbono e cinzas dos mexilhões. A torrefação de biomassa algal e das suas misturas com biomassa lenhocelulósica permitiu obter biocarvões com potencial para valorização energética, utilização como bioestimulantes na germinação de sementes ou adsorventes para pigmentos catiónicos. O trabalho realizado demonstrou a viabilidade do tratamento dos efluentes analisados por precipitação química e biorremediação com microalgas e sugerir diferentes vias de valorização dos subprodutos sólidos gerados.