Water stress is an ongoing problem in many places in the world, while the demand for clean and safe freshwater is growing due to the increasing population. In many developing countries, water supplies often are contaminated with arsenic, fluoride, etc. Therefore, it is important to realize that water scarcity and contamination issues concern only one sector but many. HVR Water Purification AB is developing a water purification prototype – ELIXIR 500 - using the air gap membrane technology and is implemented in Odisha, India, aiming to supply with 200 litre water daily. This thesis aims to estimate future energy sources to supply this prototype and explore the possibilities of using only renewable energy resources from technical, economic, and environmental perspectives. These are achieved by firstly identifying the energy possibilities in Odisha, India, and then calculating the feasibility of each solution chosen and finally analyzing the results. Among the energy sources, which are power grid, wind and solar power, diesel generator and solar-diesel hybrid system. It is found that the energy source to the prototype supplied by the power grid is 0.057 USD per litre water, which is the cheapest option. However, it is not feasible due to the lack of electrification from the local network. Meanwhile, the solar-diesel hybridized energy system is the most economical option if renewable energy sources are integrated with 0.11 USD per litre water. / Vattenstress ett pågående problem på många ställen i världen medan efterfrågan på rent och säkert dricksvatten växer på grund av den ökande befolkningen. I många utvecklingsländer är vattenförsörjningen ofta förorenade med arsenik, fluor osv. Det är därför viktigt att inse att vattenbrist och föroreningar inte bara rör en sektor utan många. HVR Water Purification AB utvecklade en prototyp för vattenrening - ELIXIR 500 - med hjälp av luftspaltmembrantekniken (eng: air gap membrane distillation och implementeras redan i Odisha, Indien, med målet att förse 200 liter rent vatten dagligt. Denna avhandling syftar till att uppskatta de framtida energikällorna för att tillhandahålla denna prototyp och utforska möjligheterna att endast använda förnybara energikällor ur tekniska, ekonomiska och miljömässiga perspektiv. Dessa uppnås genom att först identifiera de olika energimöjligheter i Odisha, Indien, följt av beräkningar om utförbarhet för varje vald lösning och slutligen en analys av resultaten. Bland energikällorna elnät, vind, sol, diesel generator och sol-diesel hybrid system har visat sig att energikällan till prototypen som levereras av elnätet som kostar 0.057 USD per liter vatten som det billigaste alternativet, men det är inte möjligt på grund av bristen på elektrifiering från det lokala elnätet. Å andra sidan är det hybridiserade energiskombinationen med solkrafts och diesel det billigaste alternativet om förnybara energikällor ska integreras, resultatet visade att vara 0.11 USD per liter vatten.

The study of nitrate utilization as the final electron acceptor in biological phosphorus removal systems was investigated. The objectives of the study were (1) to determine whether polyphosphate (polyP) microorganisms can use nitrate as the final electron acceptor, and (2) to evaluate and compare polyP accumulation in the biomass of the system using nitrate as the terminal electron acceptor to the system using oxygen as the terminal electron acceptor. Two lab-scale biological phosphorus removal systems were operated as the A/O Process under the same conditions except for the terminal electron acceptor involved. The first system, System I, was operated as an Anaerobic/Anoxic process and the other, System II, was operated as an Anaerobic/Anoxic process. Both systems were operated at a 5-day sludge age and the same nominal hydraulic retention time of 9.1 hours (2.9 hours anaerobic, 6.2 hours anoxic or aerobic). The sludge recycle flow rate was equal to the influent flow rate. The two systems were fed with the same domestic wastewater spiked with sodium acetate and potassium phosphate to give the wastewater a COD concentration of 300-400 mg/L and a phosphorus concentration of 13-14 mg/L as P. Nitrate was fed to the second reactor of System I, while the second reactor of System II was aerated. The results showed that polyP microorganisms can use nitrate as the final electron acceptor. In this research, the Anaerobic/Anoxic system removed more phosphorus (74 mg P/day) from solution than the Anaerobic/Aerobic system (64 mg P/day). The phosphorus content of the sludge in the Anaerobic/Anoxic system was greater than that of the Anaerobic/Aerobic system, i.e. 6.5% as compared to 5.6%. The above evidence strongly confirms that polyP microorganisms can use nitrate as the final electron acceptor and that excess biological phosphorus uptake occurs under anoxic condition. The implication is that COD stored in the anaerobic reactor can be used to simultaneously remove nitrogen and phosphorus, which can substantially reduce the amount of COD required for combined nutrient removal. / Master of Science

The hypothesis tested in this study is that the application of ozone to reuse aquaculture water provides more favorable conditions for hybrid striped bass at production levels. Evaluation of water quality in fish culture systems being treated with ozone was made during a production trial (1200 fish/14,OOO 1). Originally, a control and four ozonated systems with doses of 3, 13, 25, and 45 g O3/kg feed/day supported fish for experimentation but, due to mechanical failure, only the control, the 13 and 25 g O3/kg feed/day treatments completed the full 35 week study. On an equal feeding basis, concentrations of dissolved organic carbon (DOC), carbonaceous biochemical oxygen demand (CBODs), and chemical oxygen demand (COD) were lowest in the most heavily ozonated systems. Ozone increased the biodegradation of DOC. Total suspended solids, particle size and distributions were impacted by ozone's flocculating properties. The percentages of particles in the smallest size range, 5-20 microns, were greater in the control system than the ozonated systems during weeks of equal feeding rates. When feeding rates differed, the control system maintained a larger number total particles per kilogram of feed administered. The pH of the ozonated systems was lower than the control which favored the ionized (less toxic) form of ammonia. Enhanced biodegradation of organics in the ozonated systems may have increased carbon dioxide production and caused a decline in pH. Greater nitrification in the ozonated systems may have also decreased the pH. Higher total ammonia nitrogen (TAN) levels were produced in the control on an equal feeding basis. Average weekly TAN t unionized ammonia (NH3), nitrite and nitrate concentrations remained at acceptable levels across treatments and throughout the production trial. Overall, the major indication of improved system conditions due to ozone treatment was that fish raised in the ozonated systems fed steadily throughout the growth trial while the control system's culture experienced periods of reduced feeding. / Master of Science

The application of packed column air stripping systems to the removal of volatile organic contaminants (VOCs) from drinking water sources was investigated. The crucial element for the design of such systems exists in obtaining accurate predictions of mass transfer rates. The first phase of this study evaluated three semi-empirical correlations available for predicting packed column mass transfer rates. From this initial screening, the Onda model was selected for further investigation. A test data base was established from water treatment pilot study results reported in the literature. Ten separate studies were selected for evaluation, encompassing approximately 450 data points. Eleven different VOCs were encountered in these investigations, and the basic packing types tested included rings, saddles, Tri-Packs, and Tellerettes. Comparison of measured mass transfer rates with the corresponding rates predicted by the Onda correlation yielded a relative standard deviation of 17%. A ± 30% accuracy value was therefore assigned to the model based on 90% confidence limits. This assessment agrees with the observed accuracy of the correlation for the chemical engineering-based system results utilized in the model's original derivation. From the overall evaluation, no severe deficiencies and/or limitations with the Onda correlation were noted. In particular, gas-phase resistance predictions appeared reasonably accurate. However, further investigative studies involving observed column performance with larger packing materials (≥2 inches in nominal size) is encouraged to verify the accuracy of the correlation for such situations. Within the context of the evaluation procedure, several related areas were investigated. First, Henry's constant temperature relations reported in the literature were established within approximately 20% for common VOCs at low concentration levels. Secondly, the transfer unit performance model for calculating observed mass transfer rates was found sensitive to experimental measurement errors below a stripping factor of 1.5. Therefore, measured results obtained under such operating conditions must be viewed with appropriate caution. Finally, economic design boundaries for column operational parameters were established based upon optimization study results reported in the literature. / M.S.

Yes / In this paper, a one-dimensional mathematical model based on coupled differential and algebraic equations has been developed for analysing the separation mechanism of a N-nitrosamine in a spiral-wound reverse osmosis process. The model is based on Spiegler and Kedem’s work on mass transport and Darcy’s law and concentration polarization to analyse the pressure drop and mass transfer coefficient in the module feed channel respectively. The model is built using the gPROMS software suite and validated using N-nitrosamine rejection experimental data from the literature, obtained by using a pilot-scale cross-flow reverse osmosis filtration system. Analysis results derived from the model corroborate experimental data.

The objectives of this study were to determine the optimum operating conditions required for air stripping of ammonium sulfate wastewater from the caprolactam manufacturing process, to determine if biological nitrification is a viable means of treatment, and to identify any compounds present in the ammonium sulfate wastewater that (might) inhibit nitrification. This was accomplished using a combination of air stripping pretreatment, a flow-through conventional activated sludge system, powdered activated carbon (PAC) treatment and batch testing. Although biological treatment was conducted using conditions to promote nitrifier growth, nitrification was not observed using either conventional or PAC treatment. Air stripping removed fifty per cent of the ammonia-nitrogen at gas-to-liquid ratios greater than 500. However, it had no apparent effect on nitrifier inhibition. Inhibitor studies of this waste stream focused on two oximes: namely cyclohexanone oxime and methylethyl ketoxime (MEKO), which were both found in the wastewater in concentrations of 50-150 mg/L. The conclusion of this work is that cyclohexanone oxime is not inhibitory to nitrification .in concentrations less than 100 mg/L; however, MBKO was found to be inhibitory at concentrations as low as 14 mg/L. Furthermore, the inhibitory effect appeared to be pH dependent with increasing inhibition at pH less than eight. The implications of these findings for the design and operation of a full-scale treatment facility are numerous. The optimum pH range for a full-scale facility would be narrow due to the requirement for a pH high enough to decompose MEKO while maintaining a pH low enough to prevent free ammonia toxicity. / M.S.

The objectives of this project were: 1) to ascertain the feasibility of using a two-stage foam separation system, with foam fractionation or air flotation as the second stage, to treat a tarsand extraction wastewater; and, 2) to evaluate the effects of four operational variables on the second stage performance. The wastewater was a tar-in-water emulsion collected during a steamflood extraction experiment conducted by the Department of Energy's Laramie Energy Technology Center on a tarsand deposit in eastern Utah. The four operational variables considered were chemical dose, hydraulic detention time, air flowrate, and temperature. To achieve these objectives a two-stage system was devised. In the first stage, polymer-aided air flotation removed the bulk of the tar. With the second-stage foam fractionation system, 16 trials were conducted using the cationic surfactant, EHDA-Br. In the second-stage air flotation system, 24 trials were conducted, eight with no polymer addition and 16 with the addition of the low molecular weight, strongly cationic polyelectrolyte, Betz 1195. Ten trials were then conducted at the set of conditions believed to give the best treatment of the water. The effluents were tested for TOC, COD, suspended solids (SS), and total solids. It was found that either of the two-stage systems would give TOC, COD, and SS reductions greater than 98 percent, although the polymer-aided air flotation system was found to be the best second stage process. The replicate trials consistently produced data very close to the best treatment achieved in the experimental trials, thus showing the reproducibility and stability of the two-stage process. / M. S.

This project determined the thermodynamic potentials for various reactions between reduced manganese (Mn²), manganese oxide (MnO₂(s)), chlorine dioxide (Cl0₂), and potassium permanganate (KMnO₄). Based on these findings, laboratory analyses were performed to determine if these reactions would occur under simulated water treatment plant conditions. In addition, a speciation procedure was developed to quantify the various species of manganese and chlorine dioxide present in a single sample. The reactions and the speciation procedure were evaluated at TOC concentrations ranging from < 1.0 mg/L to 5.0 mg/L and at pH 6.0 and 8.0. The speciation procedure yielded a reliable measure of Mn², insoluble manganese, and Mn⁺⁷; however, the Mn⁺⁷ evaluation could be disrupted by the presence of free chlorine. The determination of Cl0₂ and Cl0₂- concentrations was also possible; however, the C10₂- concentration was subject to error. The laboratory analyses revealed that Cl0₂ was unable to oxidize either Mn² or MnO₂(s) to Mn⁺⁷ under any of the thermodynamically favored conditions. Both KMn0₄ and Cl0₂ selectively oxidized reduced organic material before reducing the concentration of Mn². When C10₂ and KMnO₄ were added simultaneously, the ClO2 reacted preferentially with the reduced materials. Only after the Cl0₂ concentration was exhausted did the MnO₂⁻ begin to oxidize the reduced species. / Master of Science

Past research regarding complexed iron has focused on the resistance to and kinetics of oxidation by O₂(aq) and the extent of stabilization. The 0.45 um filter was typically used to differentiate between dissolved and particulate iron. This research investigated Fe(II) oxidation by free chlorine and ClO₂ in the presence of DOC by varying the pH, DOC to Fe ratios, DOC sources, oxidant dosages, and contact time. Complexed iron removal by alum coagulation with and without oxidant addition was also examined. Particulate, colloidal, and soluble iron were differentiated by the use of 0.2 um filters and 100K ultrafilters. Ultrafiltration and oxidation studies revealed that, at the DOC-to-iron ratios used for this research, not all of the Fe(II) in solution was actually complexed. Thus, oxidation studies represented the oxidation of uncomplexed Fe(II) to Fe(III), which was then complexed by the higher molecular weight DOC. Results indicated that particulate iron formation (as defined as retention by a 0.2 um filter) was a function of the DOC source and oxidant used for testing. The formation of colloidal iron (as defined by retention on 100K ultrafilter) due to oxidation was dependent upon the initial DOC-to-iron ratio and the DOC source. A correlation between DOC adsorption to iron oxide solids and the solution pH, initial DOC-to-iron ratio, and the oxidant used was also evident. Complexed Fe(II) was removed from solution by alum coagulation. Oxidant addition to alum coagulation was necessary to effectively remove uncomplexed Fe(II) (in the presence of DOC) from solution. / Master of Science

Most taste-and-odor problems in the United States are caused by algal blooms in rivers and reservoirs. In the past, most of the attention has been focused on the formation of geosmin and MIB by blue-green algae (cyanobacteria), which cause earthy and musty odors, respectively. Little work has been performed, however, on equally obnoxious odors caused by other golden-brown and yellow-brown algae which are responsible for fishy, grassy, floral, and melon odors. Additionally, the production of odorous compounds can occur upon oxidation of a nonodorous parent compound. The objective of this research was to determine the effect of three oxidants - chlorine, potassium permanganate, and chlorine dioxide - on solutions of pure odorous as well as nonodorous compounds and algal extracts containing a mixture of odor-related compounds. Oxidant dosages used were in the ranges expected during water treatment. Rashash (1994) identified several odor-causing compounds in pure cultures of golden-brown, yellow-brown, green, and blue-green algae. The compounds selected for oxidation during this study were isolated by Rashash (1994) and are as follows: isovaleric acid (rancid, dirty socks), β-cyclocitral (tobacco, grape), phenethyl alcohol (roses), myristic acid (odorless), palmitic acid (odorless), linoleic acid (odorless), and linolenic acid (watermelon). All seven compounds were oxidized and evaluated by a trained flavor panel for sensory analysis. Because the three oxidants used in this study produced substantial changes in the odors of linoleic acid and linolenic acid, test solutions buffered to a pH of 7 of linoleic acid and linolenic acid were further evaluated by Flavor Profile Analysis (FPA) for sensory determination and gas chromatography/mass spectroscopy (GC/MS) for quantitative measurement of odorous compounds. Volatile compounds produced by Synura petersenii (fishy/cucumber) were also analyzed and evaluated. When linoleic acid (odorless) was treated with potassium permanganate (0.25 mg/L, 1.0 mg/L, and 1.5 mg/L) and chlorine dioxide (1.0 mg/L and 2.0 mg/L), a grassy odor was produced at an FPA intensity of 2-4 (weak). The compound causing this odor was confidently identified from GC/MS analysis as n-hexanal. The compound 2,4-decadienal, which exhibits a frying odor, was also identified in oxidized samples and could contribute to off-odors. Chlorine dioxide and potassium permanganate at the same doses were also effective in eliminating watermelon odors in linolenic samples. Flavor Profile Analysis of samples treated with chlorine was inconclusive since chlorine and acetone, which was used as an organic solvent, produce an alcohol odor at an FPA intensity of approximately 2 (weak) which masked other odors present. Flavor Profile Analysis of oxidized Synura extracts indicated that the fishy odor was destroyed and cucumber or grassy odors were unmasked. Potassium permanganate at a concentration of 0.25 mg/L was effective in eliminating all odors in Synura culture samples. Chlorine and chlorine dioxide at concentrations of 2.0 mg/L and 3.0 mg/L, respectively, eliminated the fishy odor in Synura samples. In both cases, however, vegetation or grassy odors were detected at an FPA intensity of less than 2 (very weak). / Master of Science