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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Análise comparativa do desempenho de reator anaeróbio híbrido e reator de manto de lodo de fluxo ascendente (UASB) aplicados ao tratamento de esgoto sanitário

Hoyos, Nestor Leonel Muñoz January 2016 (has links)
O presente trabalho teve como objetivo principal avaliar a performance e a estabilidade operacional de uma nova configuração de um reator anaeróbio híbrido (RAH) que combina um filtro anaeróbio de fluxo descendente seguido de uma câmara de manta de lodo de fluxo ascendente comparativamente ao reator UASB nas mesmas condições operacionais aplicados ao tratamento de esgoto sanitário. A avaliação da eficiência de remoção de remoção da matéria orgânica e dos sólidos suspensos nos reatores piloto foi por meio de testes da DQO, DBO, sólidos em suspensão totais (SST) e dos sólidos em suspensão voláteis (SSV).Os reatores UASB e RAH foram operados por um período de 240 dias na fase 1 e 150 dias na fase 2 com vazão afluente de 1,6 m3/h e TDH de 11,8 h. O TDH médio na câmara de entrada do RAH foi de 2,7h e de 9,1h na câmara ascendente de manto de lodo. Os reatores piloto apresentaram capacidade de tratamento para suportar os choques de carga orgânica devido à variabilidade do esgoto bruto. A eficiência de remoção de matéria orgânica em termos de DQO foi de 66% e 59% para o UASB e RAH, a eficiência de remoção de SST atingiu valores de 65% e 63% respectivamente, aliás, o reator UASB apresentando valores superiores de desempenho operacional em quase todos os parâmetros de monitoramento dos processos de digestão anaeróbia os valores médios dos parâmetros DQO, DBO5, SST e SSV não tiveram diferenças estatisticamente significativas. O pH para os sistemas piloto esteve na faixa ideal para o desenvolvimento dos microorganismos anaeróbios (6,5 a 7,5) e a alcalinidade e os AGVs demonstraram estabilidade dos reatores, corroborados pela estabilidade do pH no interior de cada sistema. A velocidade ascensional na câmara de manta de lodo (0,45 m/h) não causou efeito adverso na qualidade do efluente em termos de SST, com valor médio de 39,8 mg/L, na mesma faixa observada no reator UASB (41,6 mg/L). Foi observada menor concentração de biomassa no reator RAH (distribuição vertical) comparativamente ao reator UASB segundo os perfis verticais de lodo, entretanto, este fato não comprometeu a sua eficiência de remoção de matéria orgânica e dos sólidos suspensos. A retirada do lodo de excesso dos sistemas piloto foi baseada na relação STV/ST para estimar a fração de biomassa, a freqüência do descarte foi de 1 vez por mês retirando o equivalente aos 10% do volume de lodo das tomadas que apresentaram uma fração de STV menor que 50%. É viável a implementação da turbidez como parâmetro de detenção de perdida de lodo no efluente dos reatores anaeróbios devido a que a turbidez e os SST apresentaram uma relação direta o que ajudaria a simplificar mecanismos de controle operacional para a toma de decisões nas estações de tratamento, sendo que a turbidez é um parâmetro de leitura rápida “in situ” e poderia advertir do excesso de lodo ao interior do reator. Foram empregados diferentes métodos titrimétricos para a determinação dos AGVs no efluente do RAH e UASB. Após análise dos resultados, recomenda-se o uso do método de KAPP e RIPLEY para a determinação dos AGVs pela simplicidade metodológica e pela rapidez na obtenção do resultado. / This study aimed to evaluate the performance and operational stability of a new configuration of a hybrid anaerobic reactor (RAH) combining an anaerobic filter downflow followed by a sludge blanket chamber upflow compared to UASB in same operating conditions applied to sewage treatment. The evaluation of organic matter removal and removal efficiency of suspended solids in the pilot reactor was by testing COD, BOD, total suspended solids (TSS) and volatile suspended solids (VSS). The RAH and UASB reactors were operated for a period of 240 days in the first phase and 150 days in phase 2 with the inlet flow of 1,6 m3/h and 11,8h TDH. The average TDH RAH in the inlet chamber was 2.7h and 9,1h in ascending chamber sludge blanket. Pilot reactors showed treatment capacity to support organic shock loads due to the variability of raw sewage. The organic matter removal efficiency in terms of COD was 66% and 59% for the UASB and RAH, the TSS removal efficiency reached values of 65% and 63% respectively, by the way, the UASB presenting performance values higher operational in almost all parameters of the monitoring anaerobic digestion processes mean values of the parameters COD, BOD5, TSS and VSS were not statistically significant differences. The pH for the pilot systems was in the ideal range for the development of anaerobic microorganisms (6,5 to 7,5) and alkalinity and Volatile Fatty Acids (VFA) demonstrated stability of reactors corroborated by the pH stability within each system. The upflow velocity in the sludge blanket chamber (0,45 m/h) caused no adverse effect on effluent quality in terms of TSS, with an average of 39,8 mg/L, in the same range observed in UASB (41,6 mg/L). It was observed lower concentration of biomass in the reactor RAH (vertical distribution) compared to UASB second vertical sludge profiles, however, this fact did not compromise its removal efficiency of organic matter and suspended solids. The withdrawal of the pilot systems excess sludge was based on TSV/TS ratio to estimate the biomass fraction, the frequency of disposal was 1 once a month by removing the equivalent of 10% of the outlets sludge volume that had a fraction of TSV less than 50%. The implementation of turbidity as sludge lost detention parameter is viable in the effluent of the anaerobic reactors due to turbidity and TSS showed a direct relationship which would help simplify operational control mechanisms for decision making in treatment plants, wherein the turbidity is a quick read parameter "in situ" and could warn of excess sludge inside the reactor. Different titrimetric methods were employed for the determination of VFA and the effluent from the UASB and RAH. After analyzing the results, we recommend the use of KAPP and RIPLEY method for the determination of VFA by methodological simplicity and speed in obtaining results.
222

Aplicabilidade do método 1623 e do método de filtração em membranas para detecção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em amostras hídricas considerando diferentes faixas de turbidez, e estudo da etapa de purificação por separação imunomagnética : Applicability of method 1623 and membrane filtration method for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in water samples considering different levels of turbidity, and study of immunomagnetic separation phase / Applicability of method 1623 and membrane filtration method for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in water samples considering different levels of turbidity, and study of immunomagnetic separation phase

Pinto, Diego de Oliveira, 1987- 28 September 2018 (has links)
Orientador: Romeu Cantusio Neto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-09-28T14:16:54Z (GMT). No. of bitstreams: 1 Pinto_DiegodeOliveira_M.pdf: 2983083 bytes, checksum: 203eb1379711790b56fd1c53f7740c0c (MD5) Previous issue date: 2013 / Resumo: Os protozoários patogênicos Giardia spp. e Cryptosporidium spp. estão entre os principais contaminantes associados à veiculação hídrica e seu monitoramento em águas de abastecimento público é determinado pela Portaria n. 2.914/2011, do Ministério da Saúde do Brasil. Este trabalho foi dividido em duas partes. Na primeira, foi realizado um estudo da aplicabilidade do Método 1623 utilizando Filta-Max® (FMx) e Método de Filtração em Membranas (FM). Cistos de Giardia spp. e oocistos de Cryptosporidium spp. foram inoculados artificialmente em amostras de água bruta superficial proveniente do rio Atibaia, coletadas na cidade de Campinas/SP, Brasil, e agrupadas de acordo com faixas de turbidez. Cistos de Giardia spp. naturalmente presentes nas amostras foram detectados em todas as faixas de turbidez por ambos os métodos. O método de FM atendeu aos critérios de controle de qualidade analítica da USEPA em todas as faixas de turbidez. Não houve diferença estatística significativa entre os métodos de FMx e FM. Na segunda parte deste trabalho, foi feito um estudo da etapa de purificação por Separação Imunomagnética (IMS) no qual foi avaliado o desempenho dos procedimentos de dissociação: ácida e térmica; bem como investigado possíveis causas de perdas dos organismos-alvo durante execução desta etapa. A dissociação ácida apresentou maior média de eficiência de recuperação e precisão do que a dissociação térmica para cistos de Giardia spp.. Para oocistos de Cryptosporidium spp. não houve diferença estatística significativa. Após o procedimento de dissociação, tanto ácida quanto térmica, haviam cistos e oocistos aderidos às beads (micro-esferas magnéticas) que seriam descartadas de acordo com o protocolo padrão da IMS / Abstract: The pathogenic protozoa Giardia spp. and Cryptosporidium spp. are some the major waterborne contaminants and their monitoring in water supply is determined in Decree no. 2.914/2011, the Brazil¿s Ministry of Health. This study was divided in two parts. In the first, a study was conducted to evaluate the applicability of two methods for concentration of pathogenic protozoa Giardia spp. and Cryptosporidium spp. in water samples: Method 1623 using Filta-Max® (FMX) and Membrane Filtration (MF) Method. Giardia spp cysts and Cryptosporidium spp oocysts were artificially inoculated in samples of raw surface water from the Atibaia River, collected in Campinas/SP, Brazil, and grouped according to ranges of turbidity. Giardia spp. cysts naturally present in the samples were detected in all ranges of turbidity by both methods. The method of FM met the criteria for analytical quality control of USEPA in all ranges of turbidity. There was no statistically significant difference between the methods of FM and FMX. In the second part of this work, a study was made of the purification step by immunomagnetic separation (IMS) in which was evaluate the performance of the dissociation procedures: acid and heat, as well as investigating possible causes loss of target organisms during execution of this step. The acid dissociation showed higher mean recovery efficiency and accuracy than heat dissociation for Giardia spp.. For Cryptosporidium spp. difference was not statistically significant. After the dissociation procedure, both acid and heat, cysts and oocysts were still adhered to the beads (magnetic microspheres) that would be discarded, according to the standard protocol of IMS / Mestrado / Relações Antrópicas, Meio Ambiente e Parasitologia / Mestre em Biologia Animal
223

Turbidity Dynamics during High-Flow Storm Events in the Clackamas River, Oregon 2006-2012

Doyle, Micelis Clyde 22 September 2017 (has links)
Turbidity is a useful parameter that can be utilized to help understand the water quality in a river and is an expression of the optical properties of a liquid that cause light rays to be scattered and absorbed rather than transmitted in straight lines. A total of 41 storm events occurring during water years 2006-2012 were analyzed for this study. A hysteresis index (HI) was used to assess the difference in turbidity on the rising and falling limbs of a storm-hydrograph. The upstream Carter Bridge site exhibited a clockwise (C) hysteresis in 38 of 41 storm events and counter-clockwise (CC) hysteresis in three storm events. The downstream Oregon City site exhibited clockwise hysteresis in 29 of 41 storm events and counter-clockwise hysteresis in 12 storm events. Paired t-test comparisons of calculated HI measured during storm events showed that the upstream forested site Carter Bridge had a statistically significant higher HI than the downstream Oregon City site, suggesting that particles that contribute to increasing turbidity and suspended sediment at the upstream site are delivered to the river earlier in the storm event in comparison to the downstream Oregon City site. In contrast particulate matter and suspended sediment was more likely to be higher on the receding limb of the storm hydrograph at the downstream site in comparison to the upstream monitoring location. Multiple linear regression analysis determined the major hydrological and meteorological controls influencing turbidity over the period of a storm event. The log value of the change (Log ΔQ) in discharge explained 81% of the log value of change in turbidity (Log ΔTb) at Carter Bridge and 48% of the change in turbidity at Oregon City for all storms. Log ΔQ explained 85% and 50% variations of Log ΔTb at Carter Bridge and at Oregon City, respectively in the wet season. Log ΔQ explained 82% of Log ΔTb at Carter Bridge during the Dry Season and together with 3-day antecedent precipitation, Log ΔQ explained 84% of variation in Log ΔTb at Oregon City during the Dry Season. The findings of this study, which offers information about the dynamics that lead to increased turbidity events, could be helpful to researchers, regulatory agencies and water resource managers in maintaining high water quality in rivers.
224

The Impacts of Agriculture and Plantation Forestry in a Selection of Upper Catchments of the Strzelecki Ranges, Victoria

Mainville, Daniel Mark, daniel.mainville@dse.vic.gov.au January 2007 (has links)
The intensive nature of land uses in the Strzelecki Ranges poses significant threats to landscape values and water quality. A comprehensive catchment strategy was developed based on sustainability science concepts incorporating the careful management of landscape values, proper land management approaches, and government policy and legislative change to ensure that agriculture, forestry and other land uses become sustainable in this sensitive environment. The readily measurable water quality indicators of turbidity, flow, electrical conductivity, and water temperature were used to determine the impacts of the major land uses in the Strzeleckis. From a water quality perspective, there was a trend of decreasing water quality with increasing intensity in land management. However, from a total sediment load perspective, the forest area contributed the highest total sediment load due to higher volumes of steam flow suggesting that natural processes in the Strzeleckis may remain the principal mechanisms for sediment movement within the catchment. An incidental but significant finding was extensive bioturbation along the riparian zone of the plantation area, the extent of which was not observed in the other catchments. This finding suggested that bioturbation may have been the most significant contributor to poorer water quality flowing from in the plantation catchment. The project developed insights into the major environmental processes active in the upper catchment of the Morwell River. Understanding of the contributions to total sediment loads from natural erosional processes and bioturbation, findings related to the impacts on water quality from agricultural practices, and encountering negligible impacts from conservative timber harvesting practices demonstrate that catchment management approaches need to be tailored to achieve sustainability in land uses across the landscape. Key recommendations include the re-establishment and protection of riparian zones in agricultural catchments, the careful assessment and setting of stream buffer zone widths for timber harvesting operations, and the need for further work to map the extent of natural processes such as bioturbation and stream bank erosion. To mitigate these issues, government policy and legislation will need to focus on the preservation and enhancement of the Crown land riparian zones. Recommended changes to current administrative land management arrangements for these sensitive areas include a move from licensing riparian zones for agricultural practices such as grazing to conservation.
225

Use Of Calcium-alginate As A Coagulant For Low Turbidity Waters

Yuksel, Mete Avni 01 January 2005 (has links) (PDF)
This study aims to investigate the possibility of using calcium-alginate as a coagulant in low turbidity waters. Jar tests were initially performed with synthetically prepared turbid waters to investigate the effect of alginate and calcium concentrations, alginate&rsquo / s molecular weight, rapid mixing time and speed (schedule), initial pH and alkalinity of synthetic water on turbidity removal efficiency of calcium-alginate system step by step. Alum as a coagulant was then used in jar tests conducted with synthetic water to compare with calcium-alginate in terms of its turbidity removal efficiency and produced sludge properties. Finally, raw water acquired from water treatment plant was tested for treatability by using calcium-alginate based on previously determined optimum parameters via jar tests. Experiments of calcium-alginate system with synthetic water showed that calcium was a key parameter in coagulation and high molecular weight alginate performed better in turbidity removal. Significant improvements in turbidity removal were observed when mixing schedules were rearranged / especially in case of increasing rapid mixing time following calcium dosing. Calcium-alginate system neither was notably affected by pH or alkalinity nor did significantly change the pH or alkalinity of the medium. Alum worked well in turbidity removal with additional adjustments of pH and alkalinity, however / alum produced higher quantities of sludge than calcium-alginate system. &ldquo / Raw water&ldquo / experiments with calcium-alginate did not result in desired level of turbidity removals due to the excessively different characteristics of this water compared to the synthetically prepared turbid water.
226

Image Processing Using the Least-Squares Approximation for Quality Improvement of Underwater Laser Ranging

Wu, Chen-Mao 29 June 2003 (has links)
This paper attempts to use image processing methods to reduce the influences of ambient light and scattering effect on the performance of an underwater range finder. The Taguchi method, as well, is employed to increase the repeatability of underwater range finding. In this study, the image processing methods of the least-squares approximation, brightness and contrast adjustment, and primary color processing are presented. The illumination center is also used to estimate the position of the laser spot in the image. In addition, a bandpass optical filter at the receiving end is used to investigate the effects of filters on the quality of range finding. To verify the effectiveness of the proposed image processing methods, a series of DOE process runs are carried out to study effects of the design parameters on quality of range finding. For each image processing method, its corresponding control factors and levels are assigned to an inner orthogonal array. To make the proposed image processing methods robust against noises, both environmental illumination and turbidity are forced into the experiments by utilizing an outer orthogonal array. Images for processing are then captured under different noise conditions in accordance with the allocation of the outer noise array. And, according to the layout of the inner array, the S/N ratio of each treatment combination is calculated. After that, the optimum combination of control factors is predicted through the analysis of variance. Then, the confirmation experiments are carried out to verify that the combination of control factors at the perceived best levels is valid. Based on the results of experiments and analyses, it is found that the least-squares approximation is better than other proposed image processing methods for increasing the quality of range finding. Moreover, the effect of increasing quality of range finding by using the least-squares approximation is superior to that of using a bandpass optical filter. Even though a range finding system has incorporated a bandpass optical filter for filtering out unwanted noises, the quality of range finding can still be increased distinctly while the algorithm of the least-squares approximation is employed. As well, the least-squares approximation is feasible to reduce the scattering effects in the laser images if the size of the sparse backscattering light spot is smaller than that of the target light spot.
227

Failure mechanics, transport behavior, and morphology of submarine landslides

Sawyer, Derek Edward 20 November 2012 (has links)
Submarine landslides retrogressively fail from intact material at the headwall and then become fluidized by strain weakening; the final deposits of these flows have low porosity, which controls their character in seismic reflection data. Submarine landslides occur on the open slope and also localized areas including margins of turbidite channel-levee systems. I develop and quantify this model with 3-D seismic reflection data, core and log data from Integrated Ocean Drilling Program Expedition 308 (Ursa Basin, Gulf of Mexico), flume experiments, and numerical modeling. At Ursa, multiple submarine slides over the last 60 ky are preserved as mass transport deposits (MTDs). Retrogression proceeded from an initial slope failure that created an excavated headwall, which reduced the horizontal stress behind the headwall and resulted in normal faults. Fault blocks progressively weakened until the gravitational driving stress imposed by the bed slope exceeded soil strength, which allowed the soil to flow for more than 10 km away from the source area. The resulting MTDs have lower porosity (higher bulk density) relative to non-failed sediments, which ultimately produces high amplitude reflections at the base and top of MTDs. In the laboratory, I made weak (low yield strength) and strong flows (high yield strength) from mixtures of clay, silt, and water. Weak flows generate turbidity currents while moving rapidly away from the source area. They create thin and long deposits with sinuous flow features, and leave behind a relatively smooth and featureless source area. In contrast, strong flows move slowly, do not generate a turbidity current, and create blocky, highly fractured source areas and short, thick depositional lobes. In Pleistocene turbidite channels of the Mississippi Fan, deep-seated rotational failures occurred in the flanking levees. The rotational failures displaced material into the channel from below where it became eroded by turbidity flows. This system achieved a delicate steady state where levee deposition and displacement along the fault into the channel was balanced by erosion rate of turbidity flows. This work enhances our understanding of geohazards and margin evolution by illuminating coupled processes of sedimentation, fluid flow, and deformation on passive continental margins. / text
228

Life cycle analysis of sediment control devices

Troxel, Cameron Francis 20 September 2013 (has links)
Sediment control devices (SCDs) are critical to reducing the contamination of waterways from adjacent construction sites. Perimeter sediment controls retard the flow of surface runoff water originating on site and subsequently reduce solid, nutrient, and metal concentrations suspended in the flowing water. Silt fence is a commonly used SCD comprised of geotextile filter fabric, steel or wood support posts, and wire mesh reinforcement. The Georgia Department of Transportation (GDOT) uses an extensive amount of silt fence every year, and because of high degradation of geotextile in the field, the silt fence installations are rarely recycled. This research measures the performance of five SCDs (two types of silt fence, mulch berm, compost sock, and straw bales) at suspended solid, turbidity, nutrient, and metal reduction. A life cycle analysis (LCA) is performed to identify environmental impacts associated with material production, assembly, installation, use on site, and disposal. An impact analysis is performed according to for each SCD. Results of the impact analysis are compared to determine the SCD with lowest overall environmental impact. Results of the SCD performance study show that silt fence installations performed the best at reducing suspended solids and turbidity, mulch was best at reducing nutrients, and compost was the best at reducing metal concentrations. The life cycle impact analysis indicates that a mulch berm is the SCD with the lowest overall environmental impact. The impact analysis included global warming potential, acidification, eutrophication, and aquatic toxicity.
229

Une solution optique pour la mesure simultanée in-siut de la salinité et la turbidité de l'eau de mer

Hou, Bo 11 January 2012 (has links) (PDF)
Salinity and turbidity are two important seawater properties for the physical oceanography. The study of physical oceanography requires a compact high-resolution in-situ salino-turbidi-meter. The main objective of this work is to propose, design and implement an optical solution to simultaneously measure the seawater salinity and turbidity. Our first study is carried out to design a high-resolution refractometer based on a laser beam deviation measurement by a Position Sensitive Device (PSD). The refractive index measurements obtained by the voltage value delivered by PSD have been evaluated to quantify the performances of the sensor. According to the obtained results, it is clear that this PSD-based refractometer is attractive for innovative applications in metrology. However, PSD lacks the capability to retrieve the power distribution information of laser beam, which is related to the turbidity measurements. On the contrary, Charge-Coupled Device (CCD) gives much more information of laser beam than PSD. In the second part of the thesis, a performance comparison between PSD and CCD combined with a centroid algorithm are discussed with special attention paid to the CCD-based refractometer. According to the operating principle of CCD-based system, five factors of CCD-based system: image window size, number of processed images, threshold, binning and saturation are evaluated to optimize the CCD-based refractometer. By applying the optimized parameters, the performance of CCD-based refractometer is better than PSD-based refractometer in measuring the refractive index. Furthermore, by applying different post-processing algorithms, CCD-based system possesses the capability of measuring the power distribution sensitive quantities. To show this advantage of CCD-based system, the attenuation measurement method is used to measure turbidity without modifying the refractometer configuration. The turbidity measurement and salinity measurements influence each other in a refractometer. To overcome these influences, a CCD combined with a new location algorithm is used to measure both the refractive index and the attenuation. Several simulations and experiments are carried out to evaluate this new method. According to the results, the way to improve the resolution is discussed as well. Comparing to the nephelometer specified by the NTU standard, our method has been proved as a valid method to measure turbidity. By studying the performances of CCD-based refracto-turbidi-meter, 3 new prototypes are proposed to improve the salinity and turbidity measurement performance at the end of this thesis.
230

Use Of Calcium Alginate As A Coagulant In Water Treatment

Coruh, Hale Aylin 01 September 2005 (has links) (PDF)
Coagulation and flocculation processes are important parts of water and wastewater treatment. Coagulation or destabilization of colloidal suspensions results in aggregation of colloidal particles by physical and chemical processes. Flocculation results in the formation of larger and settleable structures by bridging. Alginate, a polysaccharide obtained from marine brown algae, produces a gel structure when mixed with calcium ions, which is expected to be a potential coagulant in water treatment. This study aims to determine the use of calcium alginate as a potential coagulant during water treatment and determine its capabilities and deficiencies in coagulation processes. The study was conducted on turbid water samples prepared in the laboratory and those taken from the inlet of Ankara ivedik Water Treatment Plant (IWTP) by running typical jar tests. The main experimental variables were initial alginate and calcium doses, initial turbidity of water samples and the order with which the two chemicals are dosed. The main criteria investigated to check the success of the system was the final turbidity values and the turbidity removal capacity of calcium- alginate. Experiments were conducted on three different laboratory &ndash / prepared turbid water samples and on the raw water taken from the inlet point of Ankara ivedik Drinking Water Treatment Plant (IWTP). These were prepared as high (150 NTU) medium (80 NTU) and low (10 NTU) turbidity samples. The calcium concentrations tested varied between 30 and 200 mg/L and alginate concentrations tested varied between 0.04 to 40 mg/L. Depending on the initial turbidity and initial calcium concentration of water sample the results depict that calcium alginate could be used as an effective coagulant for high (150 NTU) and medium (80 NTU) turbidity water sample especially at the calcium doses of 120 and 160 mg/L for low alginate concentration doses like 0.4 mg/L. The final turbidity met both the requirements of Drinking Water Standards applied in Turkey and Europe. Generally, the higher the initial turbidity was, the higher the turbidity removal efficiency achieved, even with very low alginic acid concentration. As the initial turbidity decreased, initial concentration of calcium required for the effective coagulation processes decreased. However, for low (10 NTU) turbidity water samples the system did not work properlyHowever, for low turbidity water samples, the turbidity removal efficiency decreased, and it was difficult to meet the limits.

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