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Study of addition of non-hazardous industrial and municipal wastewater to bioreactor landfillsDhesi, Parminder Singh 01 October 2003 (has links)
No description available.
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Wastewater application to soils: hydraulic and nitrogen considerationsSimon, John J. January 1986 (has links)
Land application of domestic and industrial wastewaters provides an effective means of recycling water and its components into the ecosystem. Successful treatment by soil requires that wastewater is applied in quantities that both maintain infiltrative capacity of the soil and do not exceed the capacity of the soil-plant system to assimilate biological and chemical contaminants. Application of N-rich wastewaters requires that consideration be given to both the ability of the soil to transmit the hydraulic load and remove sufficient N to maintain groundwater quality standards. A textile wastewater containing high concentrations of organic N was spray-irrigated to tall fescue (Festuca arunindinacea) to determine optimum N application levels. Nitrogen balances were determined at each N level and and the potential for predicting the leaching component of the excess N applied was investigated. Historically on-site wastewater disposal systems (OSWDS) for treating septic tank effluent (STE) have been designed on a hydraulic loading basis with N pollution potential essentially ignored. Many soils have been deemed unsuitable for application of STE because of textural, water table, or landscape restrictions. The relations between soil properties, hydraulic performance of OSWDS, and N distribution around OSWDS are evaluated.
Wastewater from a nylon processing plant was applied to 'Ky 31' tall fescue at total Kjeldahl nitrogen (TKN) levels of approximately 250, 430, and 1900 kg ha⁻¹ during 1982 and 1983. Fescue yield and N removal was comparable to agricultural yields at similar N application levels. Nitrogen balances indicate that plant uptake efficiency decreased with increasing organic N levels above the 250 kg ha⁻¹ level and that maximum uptake occurred at the 450 kg ha⁻¹ level. Most of the N not recovered in plant tissue mineralized rapidly to the nitrate NO₃⁻ form and leaching was noted during the winter and spring. This data is evaluated with quasi-transient analytical solution of the convection-dispersion equation. The movement of the solute center of mass is predicted on the basis of assumptions of piston flow as well as alternative assumptions of mixing via plate layer theory. Prediction of the location of the center of solute mass (α) provides a moving lagrangian coordinate solution around which dispersion of solute is calculated. The assumptions made about the sequence of evaporation and infiltration events significantly influence the prediction of α and hence the agreement between predicted and measured solute distribution. Both approaches give results which are within experimental error and provide a rational basis for predicting leaching losses and carry-over NO₃⁻ available to future crops.
Prototype OSWDS with low pressure distribution installed in three clayey limestone-derived soils were dosed with STE at flux densities ranging from 0.4 to 3.6 cm d⁻¹ on a trench bottom area basis. Ponding was noted in OSWDS at all sites dosed at the 3.6 cm d⁻¹ flux due to both underlying hydraulic restrictions and resultant anaerobic conditions. It is concluded that clayey B horizons low in swelling clays but moderately well structured can be dosed at flux densities up to 2 cm d⁻¹ if low pressure distribution of STE is used. Nitrification was found to be quite limited in soils where effluent was ponded above a restrictive layer but occurred readily within 30 cm below trenches which were freely drained or had matric potentials of at least 40 cm of water. Ratios of NO₃⁻ to Cl⁻ indicate that only limited denitrification can be expected and that substantial NO₃⁻ does leach from below OSWDS in the direction of water flow. / Ph. D.
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Evaluating the impact of asset management in the water industry : a case study of East Rand Water Care Company (ERWAT)Mhlongo, Thabani 04 1900 (has links)
Thesis (MPA)--Stellenbosch University, 2014. / The asset management process and strategy has been adopted and implemented within the
public sector. Although the National Treasury developed the Capital Asset Management
Guidelines to assist with the development and implementation of the asset management
system the guidelines have received very little attention over the years. The Auditor
General’s findings indicate a lack of proper implementation of the asset management process.
The study provides a clear indication of the implementation of the asset management process
by most government entities, local government municipalities and the public sector.
The outcome is that while most entities have made progress with regards to the implementation,
much remains to be done. Most entities implement the asset management process
selectively. This does not yield positive and sustainable results and they end up abandoning
the whole asset management system. The report provides the process of successful development and implementation of asset
management, it also indicate that if there are element that are missed or not properly done
the process will not yield constant results or performance and the impact on the organization
performance will not be positive. The management of the organization must ensure
that asset management is aligned with strategic objectives of the organization and performance
measurement must be directly linked with asset management, performance measurement
should be used to determine progress and implementation. Service level agreements
must be established between all relevant departments including the finance department
and there must be agreement on the objectives between all stakeholders. The key to
proper implementation is the alignment of the asset management process with the strategic
objectives of the organization.
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Achieving effective asset management for water and wastewater utilities: A comparison of policy options for a special district and a medium cityDale, Cari K 01 January 2005 (has links)
This project developed a model for effective asset management drawn from successful programs in the United States, Australia, and New Zealand. Asset management practices were examined at the City of Ontario Utilities Department; a medium sized utility, and also at the Rainbow Municipal Water District, a small sized utility. Gaps between the ideal model and the existing practices were investigated.
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A Quantitative and Qualitative Bacterial Analysis of the Sewage Disposal System of Perryton, TexasSullivan, Troy G. 08 1900 (has links)
This investigation had for its purpose the determination of first, the inefficiency of the Perryton, Texas, sewage disposal plant proper; and second the potential effectiveness of a lagoon now used to complete the sewage purification; and consequently, offset an apparent health hazard. The problem, as pursued, has consisted of first, the collection of sewage samples from the six stations listed in Table 1 over the period of time from September 23, 1949 to May 14, 1950; second, a quantitative analysis of each sample in order to determine the number of bacterial organisms present; third, a qualitative analysis of each sample in order to determine more expecially the presence of members of the genera Aerobacter, Escherischia, Salmonella and Shigella; and fourth, an attempt to evaluate the potentialities of the natural purification factors of the lagoon.
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The effect of biomass acclimation on the co-digestion of toxic organic effluents in anaerobic digestersChamane, Ziphathele January 2008 (has links)
Dissertation submitted in fulfillment of academic requirements for the Degree of Master of Technology: Chemical Engineering, Durban University of Technology, 2008. / Currently KwaZulu-Natal (KZN) province is populated with textile industry, which
produces wastewater, some of which is not biodegradable. Due to the stringent
environmental regulations the wastewater cannot be discharged into the rivers or public
owned treatment systems. The alternative solution is to co-dispose this wastewater with
easily biodegradable waste (labile effluent). The aim of this investigation was to develop a
process protocol for the codigestion of high strength and toxic organic effluents under
mesophilic conditions (35°C ± 2°C), with emphasis on the effect of biomass acclimation.
A total of four effluents were chosen for this study, two labile (distillery and size) and two
recalcitrant (scour dye and reactive dye).
Two anaerobic batch experiments and two pilot scale trials were performed. The first batch
anaerobic experiment investigated the influence of biomass source in anaerobic treatability.
The second batch test investigated, whether biomass acclimation enhanced the
biodegradability of pollutants. The pilot scale trials were the scale up version of the
biomass acclimation test.
The results showed sludge from Umbilo Wastewater Treatment Works was a superior
biomass source, producing more gas and methane compared to Mpumalanga waste. For
the high strength organic waste, the acclimated size and distillery samples produced 50%
more biogas and methane compared to non-acclimated samples. This confirms that the
biomass acclimation enhances the biodegradability. The biomass acclimation did not
enhance the biodegradability of the recalcitrant effluent (scour dye). The pilot scale trials
did not yield meaningful data; therefore it could not be proven if acclimation works on a
larger scale. / Water Research Commission
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A multi-objective approach to incorporate indirect costs into optimisation models of waterborne sewer systemsBester, Albertus J. 03 1900 (has links)
Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Waterborne sewage system design and expansion objectives are often focused on
minimising initial investment while increasing system capacity and meeting
hydraulic requirements. Although these objectives make good sense in the short
term, the solutions obtained might not represent the optimal cost-effective
solution to the complete useful life of the system. Maintenance and operation of
any system can have a significant impact on the life-cycle cost. The costing
process needs to be better understood, which include maintenance and operation
criteria in the design of a sewer system. Together with increasing public
awareness regarding global warming and environmental degradation,
environmental impact, or carbon cost, is also an important factor in decisionmaking
for municipal authorities. This results in a multiplicity of different
objectives, which can complicate the decisions faced by waterborne sewage
utilities.
Human settlement and migration is seen as the starting point of expansion
problems. An investigation was conducted into the current growth prediction
models for municipal areas in order to determine their impact on future planning
and to assess similarities between the models available. This information was used
as a platform to develop a new method incorporating indirect costs into models
for planning waterborne sewage systems.
The need to balance competing objectives such as minimum cost, optimal
reliability, and minimum environmental impact was identified. Different models
were developed to define the necessary criteria, thus minimising initial
investment, operating cost and environmental impact, while meeting hydraulic
constraints. A non-dominated sorting genetic algorithm (NSGA-II) was applied to
certain waterborne sewage system (WSS) scenarios that simulated the
evolutionary processes of genetic selection, crossover, and mutation to find a
number of suitable solutions that balance all of the given objectives. Stakeholders
could in future apply optimisation results derived in this thesis in the decision making process to find a solution that best fits their concerns and priorities.
Different models for each of the above-mentioned objectives were installed into a
multi-objective NSGA and applied to a hypothetical baseline sewer system
problem. The results show that the triple-objective optimisation approach supplies
the best solution to the problem. This approach is currently not applied in practice
due to its inherent complexities. However, in the future this approach may become
the norm. / AFRIKAANSE OPSOMMING: Spoelafvoering rioolstelsel ontwerp en uitbreiding doelwitte is dikwels gefokus op
die vermindering van aanvanklike belegging, terwyl dit die verhoging van stelsel
kapasiteit insluit en ook voldoen aan hidrouliese vereistes. Alhoewel hierdie
doelwitte goeie sin maak in die kort termyn, sal die oplossings verkry dikwels nie
die optimale koste-effektiewe oplossing van die volledige nuttige lewensduur van
die stelsel verteenwoordig nie. Bedryf en instandhouding van 'n stelsel kan 'n
beduidende impak op die lewensiklus-koste hê, en die kostebepalings proses moet
beter verstaan word en die nodige kriteria ingesluit word in die ontwerp van 'n
rioolstelsel. Saam met 'n toenemende openbare bewustheid oor aardverwarming
en die agteruitgang van die omgewing, is omgewingsimpak, of koolstof koste, 'n
belangrike faktor in besluitneming vir munisipale owerhede. As gevolg hiervan,
kan die diversiteit van die verskillende doelwitte die besluite wat munisipale
besluitnemers in die gesig staar verder bemoeilik.
Menslike vestiging en migrasie is gesien as die beginpunt van die uitbreiding
probleem. 'n Ondersoek na die huidige groeivoorspelling modelle vir munisipale
gebiede is van stapel gestuur om hul impak op die toekomstige beplanning te
bepaal, en ook om die ooreenkomstes tussen die modelle wat beskikbaar is te
asesseer. Hierdie inligting is gebruik as 'n platform om ‘n nuwe metode te
ontwikkel wat indirekte kostes inkorporeer in die modelle vir die beplanning van
spoelafvoer rioolstelsels.
Die behoefte is geïdentifiseer om meedingende doelwitte soos minimale
aanvanklike koste, optimale betroubaarheid en minimum invloed op die
omgewing te balanseer. Verskillende modelle is ontwikkel om die bogenoemde
kriteria te definiëer, in die strewe na die minimaliseering van aanvanklike
belegging, bedryfskoste en omgewingsimpak, terwyl onderhewig aan hidrouliese
beperkinge. ‘n Nie-gedomineerde sorteering genetiese algoritme (NSGA-II),
istoegepas op sekere spoelafvoering rioolstelsel moontlikhede wat gesimuleerde
evolusionêre prosesse van genetiese seleksie, oorplasing, en mutasie gebruik om 'n aantal gepaste oplossings te balanseer met inagname van al die gegewe
doelwitte. Belanghebbendes kan in die toekoms gebruik maak van die resultate
afgelei in hierdie tesis in besluitnemings prosesse om die bes-passende oplossing
vir hul bekommernisse en prioriteite te vind. Verskillende modelle vir elk van die
bogenoemde doelwitte is geïnstalleer in die nie-gedomineerde sorteering genetiese
algoritme en toegepas op 'n hipotetiese basislyn rioolstelsel probleem. Die
resultate toon dat die drie-objektief optimalisering benadering die beste oplossing
vir die probleem lewer. Hierdie benadering word tans nie in die praktyk toegepas
nie, as gevolg van sy inherente kompleksiteite. Desnieteenstaande, kan hierdie
benadering in die toekoms die norm word.
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Predicted achievement of strategic sewage disposal scheme in enhancement of marine water quality in Hong KongLoke, Hing-wa., 陸慶華. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
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The use of treated effluent for agricultural irrigation in the Bottelary River area: Effluent quality, farmers perception and potential extent.Rui, Li January 2005 (has links)
The Bottelary River area is located in a Mediterranean climate region, where the agricultural sector plays an important role. During the dry summer season, there is not enough precipitation to meet the agricultural irrigation requirements. Some farmers extract river water which is practically the final treated effluent from the Scottsdene Wastewater Treatment Works to irrigate crops. This research investigated the use of treated effluent for agricultural irrigation in this area, particularly focused on the effluent quality, farmers perception, and the potential extent.
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Detection and quantification of nitrifying bacteria from South African biological nutrient removal plantsRamdhani, Nishani 30 July 2013 (has links)
Submitted in fulfillment for the requirements for the Degree of Doctor of Technology: Biotechnology, Durban University of Technology, 2012. / Nitrification is a crucial step in biological nutrient removal (BNR) processes, mostly carried
out by a group of nitrifying bacteria which includes ammonia-oxidising bacteria (AOB) and
nitrite-oxidising bacteria (NOB). Nitrification failure has proven to be a common operational
problem in full-scale wastewater treatment plants (WWTP) since nitrifying bacteria are very
sensitive to sudden changes in environmental or plant operating conditions. The current
investigation was carried out to advance our understanding of the distribution of nitrifying
bacterial populations and their performance at three different BNR plants in KwaZulu-Natal,
South Africa. The latest molecular techniques such as fluorescent in situ hybridisation
(FISH)-confocal scanning laser microscopy (CSLM), polymerase chain reaction (PCR) and
real-time quantitative PCR (Q-PCR) were applied to detect and quantify nitrifying bacteria.
When using FISH to target the nitrifying population, it necessitated optimising pre-treatment
protocols of the samples to improve accuracy during quantification. Sonication was found to
be the superior method of dispersion based on the least disruption of nitrifier cell integrity,
irrespective of the sludge type.
The effect of plant configurations and wastewater
characteristics on the distribution of the nitrifying bacterial population and subsequently on
the nitrification performance was evaluated using FISH and PCR. FISH results revealed the
dominance of Nitrosomonas (AOB), Nitrobacter (NOB) and Nitrospira (NOB) for all BNR
plants. The 16S rRNA analysis of PCR products using genus-specific primers, revealed the
presence of more than one species of the same group at these plants. Nitrosomonas spp.
including Nitrosomonas halophila, Nitrosomonas eutropha, Nitrosomonas europaea,
Nitrosomonas aestuarii and an unidentified Nitrosomonas spp. were found to dominate
among the AOB and Nitrobacter vulgaris, Nitrobacter alkalicus, Nitrobacter hamburgensis
and an unidentified Nitrobacter spp. were the dominant species for NOB. Among these
species, Nitrosomonas aestuarii, Nitrosomonas europaea, Nitrobacter hamburgensis were
detected only from the industrial wastewater samples. The efficiency of two commonly used
techniques viz., FISH and Q-PCR for the detection of nitrifiers from WWTP were also
studied and compared, specifically targeting Nitrobacter sp. Even though there were slight
variations in the quantification results, changes in the Nitrobacter community at these plants
were consistent for both FISH and Q-PCR results. Both techniques have their own limitations
and advantages. This study has helped to add to the platform of understanding the distribution
and activity of nitrifying bacteria by correlating population dynamics with the operational
parameters at full-scale level. The observations made in this study will assist researchers and
engineers to minimise future nitrification failure at full-scale BNR plants. This study also
confirmed the highly complex activities of wastewater treatment processes, which is
dependant on a number of factors. Specific AOB or NOB predominant in wastewater rather
suggests that the wastewater type and characteristics may contribute to significantly different
microbial environments. Among the AOB, Nitrosomonas dominated at all BNR plants
throughout the study period and for NOB both Nitrobacter and Nitrospira were found in
significant numbers but their dominance varied across the plants. These dissimilar, distinct
distribution patterns could be attributed to their environment which in turn impacted on the
nitrification performance of the system. It was also noted that the co-existence of more than
one group of these communities at the same plant could help the plant escape complete
functional failures such as nitrification, due to sudden changes in temperature and substrate
concentrations, as this function can be performed by different groups. Although it would have
been meritorious to conduct a nitrogen balance in this study, this was not possible since the
research focused on full-scale systems. / National Research Foundation / D
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