Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2005. / The Up-flow Anaerobic Sludge Blanket Reactor (UASB) provides a state-of–the-art solution to effluent treatment by anaerobic digestion: sludge production is dramatically lower than in other digestion processes, and energy is gained from the system if the produced biogas is converted to electricity and/or heat. The UASB is a modified fluidised bed reactor, with the solid state ‘catalyst’ being granulated anaerobic sludge, and the liquid phase the effluent that needs to be treated. A gas cap is installed to serve as a carbon dioxide and methane collector. This biogas (carbon dioxide and methane) is produced by the stepwise decomposition of complex carbohydrates and proteins via a consortium of micro-organisms living in a symbiotic environment known as a granule. A typical UASB reactor has an organic removal rate of 89-93% Chemical Oxygen Demand (COD) and operates optimally at loadings of 9.8-11 kg COD/ m3 reactor volume/day. Unfortunately, one major problem hampers the efficiency of this reactor to such an extent that the unit is only economically viable in exceptional cases; if the reactor is inoculated with un-granulated anaerobic sludge, start-up times of up to 12 months can be expected. The lengthy start-up times motivated the search for an artificial way to cultivate USAB granules. Early research (done on lab-scale, 400ml vessel volumes) proved that, under a specified set of environmental conditions, granule growth can occur in an artificial environment. Yet these laboratory-scale vessels did not facilitate scale-up or the study thereof. This led to the main problem statement of this research project: namely to design, commission, and optimise benchscale bioreactors that will generate granulated anaerobic sludge in an incubation period of 20 days. These units should also facilitate in the determining of parameters that will assist in the design of a scale-up to a UASB granule producing reactor of economically viable size. Two bench-scale reactors were initially designed specifically to “mimic” the motion found in the laboratory-scale vessels. The results from these initial reactors proved that granulation cannot only be enhanced, but granules can actually be cultivated from dispersed anaerobic sludge in a larger artificial environment over an incubation period of only 20 days. The results were still far from satisfactory, as the granules produced were irregular in shape and the yield of usable granules (2.2 kg/m3 reactor volume) insufficient. A third test reactor was designed to “mimic” roller table movement and baffles were included. These results were much better and the yield was 4.4 kg/m3 reactor volume at a baffle tipspeed of 0.0055 m/s. The optimisation was extended further to include the inoculation sludge and the feed medium. A C:N:P ratio of 10:1:4 proved to yield the best results. Monovalent anions, hydrogen concentration and a pH-level outside the 6.5 to 7.2 range evidently had an inhibitory effect on the granulation rate. After the optimisation study the third test unit produced a usable granule yield of 15.2 kg/m3 reactor volume over the 20-day incubation period. The incubation period can be separated into 3 distinct phases, namely the acidification, stabilisation and growth phases. From the mass balance it was found that most of the COD and nutrients were used for ECP production in the acidification phase. During the stabilisation phase, the COD and nutrients were mostly used for nucleus formation, and finally in the growth phase the COD was used for granule growth. To study the effect the internal surface area of the reactor has on the granulation process, 3 scale-down versions of the third test unit were constructed. Within the studied range, a yield of usable granules of 40 kg/m2 reactor internal surface area was obtained.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-11-17T13:39:14Z No. of bitstreams: 1 Ádrian Juchem Stockmanns_.pdf: 9128543 bytes, checksum: 4439d237e66a4448ce2e08a6e7298d7d (MD5) / Made available in DSpace on 2017-11-17T13:39:14Z (GMT). No. of bitstreams: 1 Ádrian Juchem Stockmanns_.pdf: 9128543 bytes, checksum: 4439d237e66a4448ce2e08a6e7298d7d (MD5) Previous issue date: 2017-08-30 / Nenhuma / Este trabalho teve os objetivos de estudar o tratamento de esgoto sanitário através de um biodigestor do tipo chinês (Etapa 1) e de um reator UASB (Etapa 2), além do tratamento de esgoto sanitário em conjunto com resíduos sólidos de restaurantes através de um reator UASB (Etapa 3). O experimento foi realizado na Estação de Tratamento de Esgotos da UNISINOS (Universidade do Vale do Rio dos Sinos), aonde inicialmente foi dada a partida nos sistemas (biodigestor e reator) através da utilização de lodo do UASB existente na ETE da UNISINOS como inóculo. Relacionando as etapas 1 e 2, as análises de cor aparente, cor verdadeira e turbidez apresentaram valores superiores nas análises de Saída durante a Etapa 1. Na Etapa 2 os resultados de cor aparente e turbidez apresentaram uma redução de 41% e 77% respectivamente. As análises de DBO apresentaram uma redução de 32% entre a Entrada e Saída do reator na Etapa 2 contra 17% na Etapa 1. Nas análises de DQO, a média considerada de remoção foi de 20% na Etapa 2 contra 52% na Etapa 1, porém as últimas análises da Etapa 2 chegaram a uma redução de 80% nas análises de Saída. Relacionando as etapas 2 e 3 as análises de cor (aparente e verdadeira), DBO e DQO apresentaram valores superiores na Saída devido a adição de RSR. Comparando com a etapa aonde não foi adicionado RSR (Etapa 2) os parâmetros analisados (com exceção do pH e turbidez) apresentaram-se superiores após a adição de RSR. Em relação a geração de biogás foi comprovado o aumento na produção de biogás após a adição de resíduos, algo que de fato ocorreu principalmente após a segunda adição de resíduo, impulsionando um aumento de aproximadamente 80% em sua geração, havendo, portanto, um indicativo da possibilidade de tratamento combinado, no mesmo reator, de esgoto sanitário e resíduos sólidos de restaurantes. Os resultados sugerem que a configuração de reator UASB (Etapa 2 e 3) possui um poder de remoção de matéria orgânica superior a configuração do biodigestor chinês (Etapa 1), o que impulsiona estudos com um período maior de operação com a introdução de RSR para um tratamento integrado (ES e RSR) em reatores UASB. / This work had the objectives of studying the sewage treatment through a Chinese-type digester (Stage 1) and a UASB reactor (Stage 2), besides the sewage treatment together with solid waste from restaurants through a USB reactor (Stage 3). The experiment was performed at Estação de Tratamento de Esgotos da UNISINOS (Universidade do Vale do Rio dos Sinos), where the systems were initially started (biodigester and reactor) through the use of UASB’s Iodine existing in ETE from UNISINOS as inoculum. Relating stages 1 and 2, the analysis of apparent color, true color and turbidity presented higher values in the reactor outlet analysis during stage 1. In stage 2, the apparent color and turbidity results presented a reduction of 41% and 77% respectively. The analysis of DBO presented a reduction of 32% between the inlet and outlet of the reactor in stage 2 against 17% in stage 1. In the DQO analysis, the considered mean of removal was 20% in stage 2 against 52% in stage 1, however the stage 2 latest reviews came to a reduction of 80% in the reactor outlet analysis. Relating stages 2 and 3, the color reviews (apparent and true), DBO and DQO presented higher values in the outlet due to the addition of RSR. Comparing to the stage in which no RSR was added (Stage 2), the parameters analyzed (except for pH and turbidity) presented higher after the addition of RSR. About the generation of biogas, the increase in biogas production after the waste addition has been proven, something that actually occurred mainly after the second waste addition, boosting an increase of approximately 80% in its generation, having, therefore, indicative of the possibility of combined treatment, in the same reactor, of sanitary sewage and solid waste from restaurants. The results suggest that the UASB reactor configuration (Stages 2 and 3) has a power of removal of organic matter higher than the Chinese-type digester configuration (Stage 1), which boosts studies with a longer period of operation with the introduction of RSR for a integrated treatment (ES and RSR) in UASB reactors.

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-08T18:01:37Z No. of bitstreams: 1 Dissertação-Aline Vieira Peixoto-2013.pdf: 3799528 bytes, checksum: 6a3b319d28bdad78b71d1bd2920717de (MD5) / Rejected by Jaqueline Silva (jtas29@gmail.com), reason: on 2014-12-08T20:24:04Z (GMT) / Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-12T19:33:30Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação-Aline Vieira Peixoto-2013.pdf: 3799528 bytes, checksum: 6a3b319d28bdad78b71d1bd2920717de (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-12-16T09:22:47Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação-Aline Vieira Peixoto-2013.pdf: 3799528 bytes, checksum: 6a3b319d28bdad78b71d1bd2920717de (MD5) / Made available in DSpace on 2014-12-16T09:22:49Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação-Aline Vieira Peixoto-2013.pdf: 3799528 bytes, checksum: 6a3b319d28bdad78b71d1bd2920717de (MD5) Previous issue date: 2013-07-15 / In Brazil, according to a national survey conducted by the Brazilian Institute of Geography and Statistics (IBGE, 2010), 44.8% of the municipalities use simplified domestic waste treatment systems such as septic tanks, rudimentary cesspools and dry pits. Such systems lead to the production of potentially polluting waste which requires suitable co-treatment. Several co-treatment alternatives have been proposed. The present study, which is part of the Program on Basic Sanitation Research (PROSAB), aimed to evaluate the interference caused by septage disposal from cesspools and septic tanks on the performance of the Upflow Anaerobic Sludge Blanket Reactor (UASB) in the city of Itumbiara- Goiás. The study took nine months and was divided into three distinct phases, in which the volumetric flow rate of wastewater from cesspools and septic tanks into the reactor ranged from 0.17% to 0.51%, displaying an intermediate phase of 0.34%.In the third phase, another fat flotation phase was added to the pre-treatment prior to discharge. During the study, we utilized all the waste volume from cesspools and septic tanks produced by the municipality and discharged into the Itumbiara Wastewater Treatment Plant (WWTP), already working at its full capacity. Statistical tests have proved that wastes from cesspool and septic tanks disposed into UASB reactors showed no significant difference in the final effluent quality. It was not evidenced also significant differences in the operation and maintenance of the reactors. The biological sludge from the UASB reactors got stable after being added the wastes (ratio VS/TS between 0.53 and 0.58 average). The receiving reactor’s begs had a worse efficiency but statistical tests showed that the difference was not significant when compared to the control reactors. It was observed in this study, there is no need for the pre-flotation of waste before being released at WWTP with UASB system. Thus the UASB is a viable alternative, but it is necessary to follow a protocol to establish criteria such as the waste application rate, the WWTP site for waste discharge, physical structure and people, as well as to choose for relevant parameters for the waste monitoring before co-treatment. / No Brasil, segundo Pesquisa Nacional de Saneamento Básico do Instituto Brasileiro de Geografia e Estatística (IBGE, 2010), 44,8% dos municípios utilizam sistemas simplificados para tratamento dos esgotos domésticos como: tanques sépticos, fossas rudimentares, fossas secas. Estes sistemas têm como consequência a produção de resíduos com potencial poluidor que necessitam de codisposição adequada. Diferentes alternativas de codisposição têm sido propostas. O presente trabalho, inserido na rede de pesquisa do Programa de Pesquisas em Saneamento Básico (PROSAB), tem como objetivos avaliar as interferências da disposição de resíduos de fossas e tanques sépticos no desempenho do Reator Anaeróbio de Manta de Lodo de fluxo ascendente ou Upflow Anaerobic Sludge Blanket (UASB), na cidade de Itumbiara-Goiás. O estudo teve duração de nove meses e foi dividido em três fases distintas, alterando a taxa de aplicações volumétrica dos resíduos de fossas e tanques sépticos no reator que variou de 0,17% a 0,51%, tendo uma fase intermediária de 0,34%, além de, na terceira fase, acrescentar mais uma etapa de flotação da gordura no tratamento preliminar, antes do lançamento dos resíduos. Durante a pesquisa, foi utilizado todo o volume de resíduos de fossas e tanques sépticos gerados pelo município e dispostos na ETE de Itumbiara que já trabalha com a carga máxima. Testes estatísticos comprovaram que a disposição de resíduos de fossas e tanques sépticos nos reatores UASB não apresentou diferença significativa na qualidade do efluente. Também não foram comprovadas alterações significativas na operação e manutenção dos reatores. O lodo biológico dos reatores UASB apresentou estabilidade após a disposição dos resíduos (relação SV/ST entre 0,53 a 0,58 em média). Os leitos do reator receptor apresentaram pior eficiência, porém testes estatísticos comprovaram que a diferença não foi significativa quando comparado com reatores testemunhos. Foi observou neste estudo, que não há necessidade da flotação prévia dos resíduos antes de serem lançados nas ETEs com sistema UASB. Portanto o UASB é uma alternativa viável, porém é necessário seguir um protocolo com critérios que estabelecerá a taxa de aplicação dos resíduos, o local na ETE onde será lançado o resíduo, estrutura física e de pessoal da ETE e determinar parâmetros de relevância para o monitoramento dos resíduos antes da codisposição.