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Integration of a combined UASB-ozonation treatment system for cellar effluent degradationMcLachlan, Tania 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The wine industry significantly contributes to South Africa's water demand and
subsequent pollution of the limited resource. Wastewater is produced throughout
the year with an increase in volume and organic load during the vintage season.
Anaerobic digestion (AD), specifically the upflow anaerobic sludge bed (UASB)
technology has been shown to be feasible in the treatment of cellar wastewater.
However, the legal standard for chemical oxygen demand (COD) for disposal in a
natural water resource (75 rnq.L") is often not met. The aim of the study was to
conduct a laboratory-scale investigation into the feasibility of combining pre- and
post-ozonation processes with AD in order to achieve a final COD closer to the
legal disposal limit.
While acclimatising an UASB bioreactor containing mixed anaerobic
granules to a cellar wastewater with a pH set at 8.0, stable-state conditions were
not reached. Sucrose additions to the substrate, increased substrate loads, heattreatment
of the substrate and an addition of isolated cellar effluent bacteria to
facilitate degradation prior to AD, were all unsuccessful in maintaining stable-state
in terms of COD removal efficiency. Once the substrate pH was re-set to 7.5, the
reactor stabilised. The lowest efficient operational pH was found to be 5.73
resulting in a COD removal of 88% at a substrate COD < 5 000 rnq.L". At a
substrate pH of 6.0, the lowest efficient operational hydraulic retention time (HRT)
and corresponding organic loading rate (OLR) were 19.7 hand
9.75 kg COD.m-3d-1
, respectively, with the COD removal being maintained around
84%. The reactor effluent still had a final COD of 1280 rnq.L", which was well
above the legal South African limit.
Dominant bacteria were isolated from raw cellar wastewater and identified
as Acinetobacter haemolyticus, Burkholderia cepacia and Cryseomonas luteola.
In order to investigate the possibility that ozonation improved biodegradability, the
growth of the isolates at 35°C was monitored over 24 h in sterile ozonated and
non-ozonated substrates from the vintage and non-vintage seasons. All the
isolates increased by at least 1.5 log cycles in the control substrates from both
seasons. Ozonation of the wastewater batches for 10 min at a rate of 73 rnq.L"
led to slightly increased growth of the inoculants in the substrate batch from the vintage season. For the substrates from the non-vintage season, ozonation had
an inhibitory effect on the bacterial growth.
A 5 min ozonation treatment at a concentration of 73 rnq.L" was found to
be optimal for both a pre- and post-treatment to UASB-treatment of cellar
wastewater. Both UASB treatment and ozonation were effective in reducing the
COD by 85% and 20%, respectively. The COD reduction was improved to 88%
when UASB treatment was combined with post-ozonation. The total reduction in
total suspended solids (TSS) for the combined process was 97%, compared to
80% for UASB and 73% for an ozone treatment alone. The reduction for volatile
suspended solids (VSS) was 98% compared to 81% for UASB and 73% for the
ozone treatment alone. The total reduction when using a pre-ozonation UASB
treatment combination was an average of 86% for COD. The TSS and VSS were
both reduced by 95%. Biogas production increased from 1.4 L.d-1 to 3.8 L.d-1
when an ozonated wastewater was used as substrate. When the UASB treatment
was combined with both a pre- and post-ozonation treatment process, the COD
was reduced by 89% while TSS and VSS were both reduced by 99%.
This study showed that pre- and post-ozonation treatment processes could
successfully be utilised to improve UASB treatment of cellar wastewater. Although
the legal limits for discarding into a natural resource were not met, significant
progress was made in reducing COD levels. Cellar wastewaters do however, vary
according to season and the wastewater composition could affect the efficiency of
a pre-ozonation process. / AFRIKAANSE OPSOMMING: Die wynindustrie maak "n beduidende bydrae tot die eise wat aan Suid-Afrika se
waterbronne gestel word en gevolglik die besoedeling van die beperkte hulpbron.
Afloopwater, wat in volume en organiese lading gedurende die parstyd toeneem,
word reg deur die jaar opgelewer. Anaërobiese vertering (AV), spesifiek die
"Upflow anaerobic sludge blanket" (UASB) tegnologie, is alreeds suksesvol
gebruik om kelderafloop te behandel. Die wetlike vereiste vir chemiese suurstof
behoefte (CSB) vir storting in "n natuurlike hulpbron (75 rnq.L"), word egter
dikwels nie bereik nie. Die doel van die studie was om in "n laboratorium-skaal
ondersoek AV te kombineer met voor- en na-osoneringsprossesse, om sodoende
te poog om "n CSB nader aan die wetlike standaard te verkry.
Terwyl"n UASB bioreaktor wat gemengde anaerobiese granules bevat het,
geakklimatiseer is tot kelderafloop met "n pH gestel tot 8.0, kon stabiele toestande
nie bereik word nie. Die byvoeging van sukrose tot die substraat, verhoogde
substraatladings, hitte-behandeling van die substraat en die byvoeging van
geïsoleerde kelderafloop bakterië om substraatafbraak voor AV aan te help, was
onsuksesvol om stabiliteit in terme van CSB-verwydering, te handhaaf. "n
Verstelling van die substraat pH na 7.5, het gelei tot reaktorstabiliteit. By die
laagste doeltreffende bedryfs-pH van 5.73 en substraat CSB < 5 000 rnq.L", was
die CSB-verwydering 88%. By "n substraat pH van 6.0 was die laagste
doeltreffende bedryfs-hidroliese retensie tyd en -organiese ladingstempo 19.7 h en
9.75 kg CSB.m-3d-1, onderskeidelik, terwyl die CSB verwydering rondom 84%
gehandhaaf is. Die CSB van die reaktoruitvloesel van 1 280 rnq.L", was steeds
ver bo die wetlike vereiste.
Dominante bakterië is uit kelderafloop geïsoleer en as Acinetobacter
haemolyticus, Burkholderia cepacia en Cryseomonas luteola, geïdentifiseer. Die
moontlikheid dat osonering bioafbreekbaarheid bevorder, is ondersoek deur die
groei van die isolate by 35°C oor 24 h in steriele geësoneerde en ongeësoneerde
substrate te monitor. Die substrate is berei vanaf kelderafloop wat in die
parsseisoen sowel as die nie-parsseisoen versamel is. AI die isolate het met ten
minste 1.5 log siklusse in die kontrole substrate van beide seisoene, vermeerder. Vir die kelderafloop wat in die parsseisoen versamel is, het osonering vir 10 min
teen 73 rnq.L" gelei tot effens verbeterde groei van die innokulante. Osonering
het 'n onderdrukkende effek op die groei van bakterië in die afloopwater versamel
in die nie-parsseisoen, gehad.
Osonering vir 5 min teen 'n konsentrasie van 73 rnq.L" is as optimum vir
beide voor- en na-osoneringsbehandeling tot UASB-behandeling van die
kelderafloop, gevind. UASB-behandeling en osonering het die CSB met 85 en
20% onderskeidelik, verminder. Die vermindering kon tot 88% verhoog word
wanneer UASB-behandeling met na-osonering gekombineer is. Die vermindering
in totale gesuspendeerde vastestowwe (TGV) vir die gekombineerde proses was
97%, in vergelyking met 80% vir UASB- en 73% vir osoonbehandeling alleen. Die
vermindering in vlugtige gesuspendeerde vastestowwe (VGV) was 98% in
vergelyking met 81% vir UASB- en 73% vir osoonbehandeling alleen. Die totale
CSB verwydering vir 'n voor-osonerings UASB kombinasie was gemiddeld 86%.
Die TGV en VGV is beide met 95% verminder. Biogasproduksie het ook
vermeerder vanaf 1.4 L.d-1 tot 3.8 L.d-1 toe geosoneerde afloopwater as substraat
gebruik is. Die kombinasie van UASB-behandeling met voor-osonering, sowel as
na-osonering het gelei tot 'n CSB-verwydering van 89% terwyl TGV en VGV beide
met 99% verminder is.
Hierdie studie het getoon dat voor- en na-osonering suksesvol gebruik kan
word om UASB-behandeling van kelderafloop te verbeter. Hoewel wetlike
vereistes vir storting in 'n natuurlike hulpbron nie bereik is nie, is beduidende
vordering gemaak in die verlaging van CSB-vlakke. Die verskil in die samestelling
van kelderafloop gedurende die onderskeie seisoene, kan egter die
doeltreffendheid van die voor-osoneringsproses beïnvloed.
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Avaliação de um sistema de ozonização baseado em coluna de borbulhamento / Evaluation of an ozonation system based on bubble columnPacheco, José Ricardo 20 August 2018 (has links)
Orientador: Marco Aurélio Cremasco / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-20T13:54:46Z (GMT). No. of bitstreams: 1
Pacheco_JoseRicardo_M.pdf: 2421854 bytes, checksum: 0892102a47f0322520b05c0bad2a79d9 (MD5)
Previous issue date: 2012 / Resumo: A gestão dos recursos hídricos, englobando uso de água para fins potáveis e processos industriais, tornou-se de vital importância e ganhou visibilidade na última década do século vinte. Dentre as tecnologias e processos de tratamento de água potável e residuária destaca-se a ozonização. Diante deste contexto a presente dissertação de mestrado visou construir e avaliar um sistema de ozonização baseado em coluna de borbulhamento. Foi construída uma célula de geração de ozônio para se estudar a eficiência de geração, com três gases de alimentação: ar úmido; ar seco e oxigênio. O ar úmido foi captado diretamente da atmosfera, o ar seco e oxigênio foram fornecidos através de um secador de ar e um concentrador de oxigênio respectivamente. O processo de fornecimento de ar seco e oxigênio foi o de "PSA" (pressure swing adsorption) no qual o ar atmosférico passou por uma coluna recheada com zeólita capaz de reter a umidade e moléculas de nitrogênio. A célula geradora de ozônio teve então as condições de descarga elétrica fixas e os três gases de alimentação foram passados pela mesma. A eficiência de geração de ozônio foi então comparada entre os três gases de alimentação. Os valores obtidos apresentaram consistência em relação aos valores de outros autores. Para avaliação da ozonização em fase líquida foi construída uma coluna de borbulhamento onde o ozônio foi borbulhado na parte inferior da coluna usando-se água destilada. Foram realizados experimentos: a) com recirculação da água da parte inferior da coluna até o topo; b) sentido contra-corrente água/gás; c) sentido co-corrente água/gás...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The management of water resources embracing the use of water for potable and industrial processes, has become of vital importance and has gained visibility in the last decade of the twentieth century. Among the technologies and processes for treatment of drinking water and wastewater, ozonation plays an important role. Considering this context the dissertation work aimed to construct and evaluate a system based on bubble column ozonation. An ozone generation cell was built to study the generation yield with three feed gases: humid air; dry air and oxygen. The humid air was captured directly from the atmosphere, dry air and oxygen were supplied by an air dryer and one oxygen concentrator respectively. The feed gas preparation process to supply dry air and oxygen is called "pressure swing adsorption", which the atmospheric air is passed through a column filled with a zeolite compound which retains moisture and nitrogen molecules. Ozone generation cell discharge electrical conditions were fixed, after the three feed gases were passed through the cell. Then ozone generation efficiency was measured and compared between the three feed gases. The values obtained were consistent with those obtained by other authors. To evaluate ozonation in the liquid phase a bubble column was constructed, where gaseous ozone was bubbled into the column bottom. Distilled water was chosen as the liquid medium. Experiments were carried out in the following conditions: a) recirculating water from the bottom to the top of the column; b) countercurrent flow directions between gas/liquid; c) concurrent flow directions between gas/liquid...Note: The complete abstract is available with the full electronic document / Mestrado / Engenharia de Processos / Mestre em Engenharia Química
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The combination of UASB and ozone technology in the treatment of a pectin containing wastewater from the apple juice processing industryVan Schalkwyk, Nico 12 1900 (has links)
Thesis (MSc Food Sc )--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The South African apple juice processing industry is growing rapidly and during the
harvesting season the wastewater volumes and organic loads increase significantly with a
considerable environmental impact. These larger apple juice processing wastewater
(AJPWW) volumes and chemical oxygen demand (COD) loads subsequently lead to faster
increases in the organic loading rate (OLR) of an upflow anaerobic sludge bed (UASB)
wastewater treatment system and it is necessary to know if the treatment system can
handle such drastic increases over short periods. The objective of the study were to
evaluate the efficiency of the UASB process in the treatment of an AJPWW; to determine
what effect a substrate viscosity increase, based on a pectin calcium gel has on the
performance of an UASB system, and to determine what impact ozonation has on the
pectin content, gelformation ability and biodegradability of the AJPWW.
The ability of the UASB to maintain stability during the apple-processing season
was investigated by increasing the OLR from 2.9 to over 14.0 kg COD.m-3.d-1 in 131 days.
During this time the COD removal remained constant at 85%, while the pH and alkalinity
remained at levels indicative of good reactor stability. It was thus concluded that the
UASB reactor could operate successfully during the apple-harvesting season when
wastewater volumes and organic loads increase significantly.
In the study it was found that the viscosity of the AJPWW, containing 750 mq.L-1
pectin, increased from 8.5 to 47.0 cps after a 312 rnq.L-1 Ca2
+ addition. This increased
viscosity substrate was then fed to an UASB reactor at an OLR of 15.0 kg COD.m-3.d-1.
During a 12 day increased viscosity (47 cps) feeding stage the COD removal decreased
from 94 to 11%, while the reactor pH decreased from 7.5 to 4.9. During this period, pectin
accumulated in the UASB and led to biomass washout and rapid UASB failure. The
possible elimination of pectin by ozonation was thus investigated, and a 77% decrease in
pectin content and 76% decrease in gel formation ability occurred after ozonation.
The effect of pre- and post-ozonation on the efficiency of the UASB system was
subsequently investigated. It was found that a 10 min pre-ozonation decreased the
AJPWW COD by 19% and the total suspended content by 36%, while the soluble portion
of the total COD was increased from 81.7 to 92.4%. This increase in soluble COD content
should lead to increased wastewater biodegradability. The ozonated AJPWW was then
used to replaced the raw non-ozonated AJPWW as reactor feed. Results showed that the
COD removal increased from 78 to 90% within 24 h of starting with the ozonated feed. It
was also found that the reactor stability improved after AJPWW pre-ozonation as an OLR
increase from 10.0 to 16.6 kg COD.m-3.d-1 in 23 days did not detrimentally influence the stability of the reactor. This reactor effluent (COD = 465 rnq.L-1) was then post-ozonated
which resulted in 64.8% COD and 79.0% colour reductions. The final effluent had a COD
of 180 rnq.L-1 (98% reduction).
The ability of the ozonation/digestion system as described in this study to degrade
AJPWW at a higher OLR is of value to the apple industry, as it may lead to larger organic
pollutant removals and thus a more effiecient treatment system. Increased reactor
performance will directly improve the quality of the final wastewater produced, which in
turn will have a significant impact on the treatment ability of the South African apple
processing industry currently limited by the production of large wastewater volumes. / AFRIKAANSE OPSOMMING: Gedurende die oesseisoen word groot volumes afvalwater met 'n hoe organiese lading in
die vinnig groeiende Suid-Afrikaanse appelsapprosesseringsbedryf geproduseer. Dit het 'n
groot impak op die omgewing. Die groter volumes appelsapprosesseringsafvalwater
(ASPAW) met 'n hoë organiese lading het 'n vinniger verhoging in organiese
ladingstempo's (OLT) van 'n UASB-waterbehandelingstelsel tot gevolg. Daarom is dit
belangrik om te weet of die stelsel die drastiese verhoging oor kort tydperke kan hanteer.
Die doel van hierdie studie was die evaluering van die effektiwiteit van die UASB-proses in
die behandeling van ASPAW; om te bepaal watter effek 'n substraatviskositeitsverhoging,
gebaseer op 'n pektien-kalsium-jel, op die doeltreffendheid van 'n UASB-stelsel het; en om
te bepaal watter impak osonering op die pektieninhoud, jelvormingsvermoe en
bioafbreekbaarheid van ASPAW het.
Die vermoe van die UASB om stabiliteit te handhaaf gedurende die
appelsapprosesseringseisoen is ondersoek deur die OLT van 2,9 tot bo
14,0 kg CSB.m-3.d-1 te verhoog oor 131 dae. Gedurende hierdie tyd het die chemiese
suurstofbehoefte- (CSB-) verwydering konstant gebly by 85%, terwyl die pH en alkaliniteit
ook op vlakke aanduidend van goeie reaktorstabiliteit gebly het. Daar is sodoende bewys
dat die UASB-reaktor suksesvol kan presteer tydens die appelsapprosesseringseisoen,
wanneer daar 'n beduidende verhoging in OLT plaasvind.
In die studie is daar gevind dat die viskositeit van die ASPAW, wat 750 mq.L-1
pektien bevat, van 8,5 tot 47,0 cps toeneem na die byvoeging van 312 rnq.L-1 Ca2+.
Hierdie verhoogde vikositeitsubstraat is tot die UASB-reaktor toegevoeg teen 'n OLT van
15,0 kg CSB.m-1.d-1. Gedurende 'n 12-dae toevoer van verhoogde viskositeit (47 cps), het
die CSB-verwydering van die reaktor afgeneem van 94% na 11%, terwyl die pH gedaal het
van 7,5 na 4,9. Gedurende hierdie tydperk het pektien in die UASB geakkumuleer, wat
gelei het tot die uitspoel van biomassa en vinnige UASB-reaktormislukking. Die moontlike
eliminasie van pektien, deur osonering, is daarom ondersoek. 'n Verlaging van 77% in
pektieninhoud en 76% in jelvormingsvermoe het na osonering plaasgevind.
Die effek van pre- en post-osonering op die effektiwiteit van 'n UASB-stelsel is
gevolglik ondersoek. Daar is gevind dat 'n 10 minute pre-osonering die CSB van die
ASPAW met 19% verlaag en die totale inhoud van gesuspendeerde vaste stowwe met
36% verlaag, terwyl die oplosbare gedeelte van die totale CSB van 81,7% tot 92,4%
gestyg het. Die verhoging in oplosbare CSB-inhoud behoort tot verhoogde
bioafbreekbaarheid van ASPAW te lei. Die geosoneerde ASPAW is gebruik om die rou,
ongeosoneerde ASPAW as reaktorsubstraat te vervang. Die resultate het getoon dat die CSB-verwydering verhoog het van 78% na 90% na 'n 24-uur toevoer van geosoneerde
substraat. Daar is ook gevind dat die reaktorstabiliteit toegeneem het na ASPAW
osoneering, aangesien 'n OLT-verhoging van 10,0 na 16,6 kg.CSB.m-3.d-1 in 23 dae nie die
stabiliteit van die reaktor nadelig beinvloed het nie. Hierdie reaktoruitvloeisel (CSB = 465
rnq.L-1) is hierna gepost-osoneer, wat 'n 64,8% CSB- en 79,0% kleurverlaging tot gevolg
gehad. Die finale uitvloeisel het 'n CBS-inhoud van 180 rnq.L-1 gehad (98,1%
verwydering).
Die vermoe van die osonering-/verteringstelsel om ASPAW te degradeer teen 'n hoër OLT,
soos beskryf in hierdie studie, is van waarde tot die appelsapprosesseringsbedryf,
aangesien dit tot groter organiese afvalstofverwydering kan lei en dus 'n meer effektiewe
behandelingstelsel tot gevolg kan hê. Verhoogde reaktordoeltreffendheid sal 'n direkte
verbetering tot gevolg hê in die gehalte van die finale afvalwater wat geproduseer word,
wat op sy beurt 'n beduidende impak sal hê op die behandelingsvermoe van die
appelsapprosesseringsbedryf, wat tans beperk word deur die produksie van groot volumes
afvalwater.
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Integration of anaerobic biological and advanced chemical oxidation processes to facilitate biodegradation of fruit canning and winery wastewatersSigge, G. O. (Gunnar Oliver) 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2005. / ENGLISH ABSTRACT:
Please see fulltext for abstract / AFRIKAANSE OPSOMMING:
Sien asb volteks vir opsomming
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