The compatibility of home water softeners and septic tanks is of concern for the on-site wastewater treatment community. Research has shown that high sodium levels in activated sludge plants can lead to deflocculation and poor effluent quality. Therefore, it is logical to assume that high sodium levels that result from the exchange of calcium and magnesium for sodium in home softeners could give rise to poor effluent quality from septic tanks, leading to shortened lives of drain fields. Additionally, the release of regeneration discharges to the septic tank might further damage performance. This study was undertaken to investigate the effect home ion-exchange softeners have on septic tank performance. A column study was set up and varying levels of sodium were added to wastewater influent and these were fed to columns that contained solids collected from operating septic tanks. In addition, slug influent solutions, which mimic regeneration flow, with varying amounts of excess sodium were investigated. To reinforce the lab column experiments, data were obtained from private septic tanks to determine the effluent quality from septic tanks both diverting and receiving the regeneration flow. Also utilized were graduated cylinder experiments, where the effect of sodium on grease flocculation was determined, and batch anaerobic digestion studies, which determined the effect sodium has on the production of gases and the degradation of solids. The study showed that the addition of sodium to septic tanks is likely to impact the effluent quality of sewage discharged from a septic tank to a drain field. The common way of measuring ion concentrations for comparison in this study was to obtain the monovalent to divalent ratio (M/D Ratio). This is simply the concentration of the sodium ions in solution divided by the concentrations of magnesium and calcium, on an equivalent weight basis (all other monovalent and divalent ions were negligible). Slug solutions of high levels of salts (Septic Tank Effluent M/D = 11), mimicking regeneration wastes from water softeners with an inefficient regeneration cycle, increased the effluent solids, COD and BOD. However, if the regeneration wastes contained the same amount of calcium and magnesium, but a smaller amount of sodium (Septic Tank Effluent M/D = 5), the negative effect on these effluent characteristics was greatly lessened. In an optimum case with a regeneration solution containing a minimal amount of excess sodium (Septic Tank Effluent M/D = 3), the effluent characteristics were often actually more favorable than in similar situations where the regeneration wastes were diverted (Septic Tank Effluent M/D = 2). The case studies reinforced these data, showing that sodium concentrations correlated with an increased discharge of solids to the drain field. The studies on grease flocculation as well as anaerobic digestion suggest that these processes are not affected by the sodium level. Overall, it appears that the use of home softeners with septic tanks may have an effect on solids discharge to the drain field and the level of impact will depend on the level of hardness in the water, whether the regeneration waste is discharged to the septic tank, and the amount of excess sodium present in regeneration wastes. / Master of Science

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A zeÃlita NaA (LTA) foi eficientemente obtida atravÃs de sÃntese hidrotÃrmica, onde o caulim foi usado como fonte de silÃcio e alumÃnio. A zeÃlita obtida foi caracterizada pelas tÃcnicas de difraÃÃo de raios-X, absorÃÃo de raios-X, termogravimetria (TG), calorimetria diferencial exploratÃria (DSC), microscopia eletrÃnica de varredura (MEV), espectroscopia de absorÃÃo na regiÃo do infravermelho (IV), luminescÃncia e granulometria. O refinamento dos dados obtidos nas anÃlises de difraÃÃo de raios-X, atravÃs do mÃtodo de Rietveld e do uso do software DBWS9807, possibilitou a confirmaÃÃo de uma Ãnica fase cristalogrÃfica obtida no processo de sÃntese, e o cÃlculo do tamanho das partÃculas, as quais variam de 48 nm a 74 nm. As caracterÃsticas morfolÃgicas desta zeÃlita foram evidenciadas atravÃs da microscopia eletrÃnica de varredura, onde cristais de diferentes tamanhos apresentaram forma cÃbica. Os Ãons Na+ foram substituÃdos por Ãons NH4 +, em processo de troca iÃnica simples, fazendo com que a zeÃlita adquirisse assim a forma amoniacal. A eficiÃncia deste processo foi confirmada pelas anÃlises de infravermelho, com o aparecimento de bandas em 1402 cm-1 e 1450 cm-1 apÃs a troca iÃnica, e por titulaÃÃo de neutralizaÃÃo. A estabilidade tÃrmica da zeÃlita nas duas formas iÃnicas foi analisada atravÃs de termogravimetria. As energias de ativaÃÃo para os processos termodegradativos relacionados Ãs perdas de massa por volatilizaÃÃo, as quais se referem basicamente à eliminaÃÃo de Ãgua e amÃnia presentes na estrutura zeolÃtica, variaram de 71,7 kJ.mol-1 a 205,7 kJ.mol-1. As anÃlises de luminescÃncia mostraram que o Ãon Eu3+, usado como sonda, nÃo està localizado em um centro simÃtrico e que os sÃtios onde o referido Ãon se encontra nÃo sÃo homogÃneos. O tamanho de partÃcula obtido atravÃs da granulometria foi em torno de 10 m , mostrando que os cristais da zeÃlita formam aglomerados. A zeÃlita NaA mostrou-se extremamente eficiente no abrandamento de Ãguas duras e, desta forma, apresentase como um substituinte em potencial dos polifosfatos, comumente usados em detergentes. / Zeolite NaA (LTA) has been successfully synthesized by hydrothermal route, in which kaolim was used as silicon and aluminum source. The obtained zeolite was characterized by X-ray diffraction, X-ray absorption, thermogravimetry (TG), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), infrared absorption spectroscopy (IR), luminescence and granulometry. The X-ray diffraction data refinement by Rietveld method and software DBWS9807 has made possible the confirmation of only one crystallographic phase on the synthesis process and the particle size measurements. Particle sizes vary from 48 nm to 74 nm. Zeolite A morphologic properties were observed by scanning electron microscopy analysis, in which one could observe crystals with different sizes but with the same cubic shape. Na+ ions have been replaced for NH4 +, in a simple ion exchange process. This way, zeolite A has acquired its ammoniac state. The efficiency of this process has been confirmed by infrared analysis, with the appearance of bands in 1402 cm-1 and 1450 cm-1 after ion exchange, and by acid titillation. Zeolite thermal stability, either on Na+ or NH4 + states, has been determined by thermogravimetry. Activation energies for the thermogravimetric process related to weigh loss through volatilization caused basically by water and ammonia liberation from zeolite surface, were from 71,7 kJ.mol-1 to 205,7 kJ.mol-1. Luminescence analysis has indicated that Eu3+, used as probe, is not located in a symmetric center and the sites in which the abovementioned ion is located is not homogeneous. The particle size obtained from granulometric analysis was around 10 m, what indicates agglomerations formed by zeolite crystals. According to calcium removal analyses by zeolite A, it appears as an excellent water softener and as a potential substitute for polyphosphates, frequently used in detergents.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Zeolite NaA (LTA) has been successfully synthesized by hydrothermal route, in which kaolim was used as silicon and aluminum source. The obtained zeolite was characterized by X-ray diffraction, X-ray absorption, thermogravimetry (TG), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), infrared absorption spectroscopy (IR), luminescence and granulometry. The X-ray diffraction data refinement by Rietveld method and software DBWS9807 has made possible the confirmation of only one crystallographic phase on the synthesis process and the particle size measurements. Particle sizes vary from 48 nm to 74 nm. Zeolite A morphologic properties were observed by scanning electron microscopy analysis, in which one could observe crystals with different sizes but with the same cubic shape. Na+ ions have been replaced for NH4 +, in a simple ion exchange process. This way, zeolite A has acquired its ammoniac state. The efficiency of this process has been confirmed by infrared analysis, with the appearance of bands in 1402 cm-1 and 1450 cm-1 after ion exchange, and by acid titillation. Zeolite thermal stability, either on Na+ or NH4 + states, has been determined by thermogravimetry. Activation energies for the thermogravimetric process related to weigh loss through volatilization caused basically by water and ammonia liberation from zeolite surface, were from 71,7 kJ.mol-1 to 205,7 kJ.mol-1. Luminescence analysis has indicated that Eu3+, used as probe, is not located in a symmetric center and the sites in which the abovementioned ion is located is not homogeneous. The particle size obtained from granulometric analysis was around 10 m, what indicates agglomerations formed by zeolite crystals. According to calcium removal analyses by zeolite A, it appears as na excellent water softener and as a potential substitute for polyphosphates, frequently used in detergents. / A zeÃlita NaA (LTA) foi eficientemente obtida atravÃs de sÃntese hidrotÃrmica, onde o caulim foi usado como fonte de silÃcio e alumÃnio. A zeÃlita obtida foi caracterizada pelas tÃcnicas de difraÃÃo de raios-X, absorÃÃo de raios-X, termogravimetria (TG), calorimetria diferencial exploratÃria (DSC), microscopia eletrÃnica de varredura (MEV), espectroscopia de absorÃÃo na regiÃo do infravermelho (IV), luminescÃncia e granulometria. O refinamento dos dados obtidos nas anÃlises de difraÃÃo de raios-X, atravÃs do mÃtodo de Rietveld e do uso do software DBWS9807, possibilitou a confirmaÃÃo de uma Ãnica fase cristalogrÃfica obtida no processo de sÃntese, e o cÃlculo do tamanho das partÃculas, as quais variam de 48 nm a 74 nm. As caracterÃsticas morfolÃgicas desta zeÃlita foram evidenciadas atravÃs da microscopia eletrÃnica de varredura, onde cristais de diferentes tamanhos apresentaram forma cÃbica. Os Ãons Na+ foram substituÃdos por Ãons NH4 +, em processo de troca iÃnica simples, fazendo com que a zeÃlita adquirisse assim a forma amoniacal. A eficiÃncia deste processo foi confirmada pelas anÃlises de infravermelho, com o aparecimento de bandas em 1402 cm-1 e 1450 cm-1 apÃs a troca iÃnica, e por titulaÃÃo de neutralizaÃÃo. A estabilidade tÃrmica da zeÃlita nas duas formas iÃnicas foi analisada atravÃs de termogravimetria. As energias de ativaÃÃo para os processos termodegradativos relacionados Ãs perdas de massa por volatilizaÃÃo, as quais se referem basicamente à eliminaÃÃo de Ãgua e amÃnia presentes na estrutura zeolÃtica, variaram de 71,7 kJ.mol-1 a 205,7 kJ.mol-1. As anÃlises de luminescÃncia mostraram que o Ãon Eu3+, usado como sonda, nÃo està localizado em um centro simÃtrico e que os sÃtios onde o referido Ãon se encontra nÃo sÃo homogÃneos. O tamanho de partÃcula obtido atravÃs da granulometria foi em torno de 10 m , mostrando que os cristais da zeÃlita formam aglomerados. A zeÃlita NaA mostrou-se extremamente eficiente no abrandamento de Ãguas duras e, desta forma, apresentase como um substituinte em potencial dos polifosfatos, comumente usados em detergentes.

<p> Globally, millions of people rely upon plumbing to help store and deliver safe water to building inhabitants. This water is used for drinking, cooking, washing, appliances, and other activities to protect public health and support economic activity. Water softeners are common devices used to remove minerals from water to limit scale formation in plumbing thereby protecting appliances and improving drinking water taste. Despite tens of millions of these devices in U.S. homes, little is known about how these devices impact chemical drinking water quality. Further, many homes that have softeners have been impacted by disasters such as chemical spills and wildfires and encountered hydrocarbon contaminated drinking water. At present, no information is available about hydrocarbon fate in softeners and how to decontaminate these devices. The objectives of the first chapter were to (1) determine how bench-scale and full-scale water softeners impact drinking water organic carbon, chlorine disinfectant, total cell count, and sulfur concentrations, and (2) assess the softener’s ability to be decontaminated by water flushing after hydrocarbon contamination. The objectives of the second chapter were to (1) better understand the effect wildfires have on private drinking water well infrastructure, water quality, and (2) identify practical research needs. Chapter 1 experiments revealed that both new and aged softener resins leached organic carbon compounds into drinking water, and this prompted notable reductions of drinking water free chlorine disinfectant levels. Newly installed water softeners caused first flushed water to have high levels of organic carbon (934 mg/L) with about 40% particulate organic carbon. Total sulfur concentration was also elevated. After 1 week of use, water softeners caused drinking water to have 4-8 mg/L organic carbon levels. When exposed to hydrocarbon contaminated drinking water, resins absorbed and leached benzene, toluene, ethylbenzene, and total xylenes (BTEX) for more than 2 weeks. Chapter 2 results revealed that for the private drinking water wells sampled after the 2021 Marshall Fire, semi-volatile organic compound (SVOC); No SVOCs exceeded health-based drinking water limits. No volatile organic compounds were found in either shallow or deep wells or within homeowner plumbing. Heavy metals (Li and V) were found in several wells, but these contaminants were not associated with the fire. A private well water system serving 8 properties was damaged, lost pressure, and had not been flushed or repaired 7 months after the fire due to financial and technical challenges. Thesis results provide new knowledge for utilities, health officials, and building owners who desire to better understand commercially available softeners and wildfire damage considerations for private drinking water wells. Results described here can be used to inform communications with homeowners, public health recommendations regarding plumbing safety and water use decisions following suspected or confirmed building chemical contamination and wildfires. </p>