This study was a full-scale investigation of SBR for the treatment of oily wastewater with determination of the effects of different operating conditions on process performance. It was demonstrated that under a rather complex situation, the performance of the SBR could be significantly improved, compared to the results prior to the study. In contrast to the low COD reduction, significantly higher BOD5 removals were achieved. When the waste was only composed of wasted oils, the BOD, in the effluent averaged 179 mg/I for an average removal of 87%. Also good reductions of phenols and oil & grease were attained during the study. Based on a thorough evaluation of the results the following specific conclusions are made. / Master of Science

Treatability studies were performed on oily wastewaters produced by petroleum and canning industries. Chlorine dioxide was used for the removal of phenolic compounds from these oily wastewaters. Most of phenolic compounds can be destroyed by chlorine dioxide within 15 minutes if CI02-to-phenol ratios of higher than 5.0 are provided. Factors such as pH, temperature, and COD have little effect on phenol removal. The effectiveness of chlorine dioxide treatment depends critically on the performance of the chlorine dioxide generator. High yields of chlorine dioxide generation can be achieved by maintaining the pH between 2.5 and 3.5, and by controlling the concentration of feed chemicals. For small treatment plants, chlorine dioxide treatment may be an economical process because no expensive equipment is required. / Master of Science

Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2019. / The biodiesel industry produces large volumes of biodiesel wastewater (BDWW) during the purification of crude biodiesel. This wastewater is characterised by high concentrations of chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), and fats, oils and greases (FOG) which in turn defines BDWW as a highly polluted effluent. The low nitrogen and phosphorous content of BDWW creates an unfavourable environment for the growth of microorganisms, thereby making it difficult to degrade naturally. Biodiesel companies discharge untreated non-compliant wastewater directly to the municipal sewer system. Treatment prior to discharge is a necessity since the disposal of untreated BDWW may raise serious environmental concerns (i.e. disturbance of biological ecosystems) resulting in penalties liable by non-compliant companies due to the implementation of the waste discharge charge system (WDCS) which is regulated by the industrial waste discharge standard limits in South Africa (SA). This study aimed to combine the advantages of the conventional anaerobic baffled reactor (ABR) system with microbial fuel cell (MFC) technology resulting in an innovative technology used to treat high strength industrial BDWW at ambient conditions. Many studies have reported effective treatment of BDWW, however to date literature implementing an ABR equipped with MFC technology has not been reported. The main objectives of the study were to determine which parameters do not meet the industrial wastewater discharge standard limits, whether pH and carbon:nitrogen:phosphorous (C:N:P) ratio adjustments will suffice prior to treatment with the ABR-MFC, the maximum power density (PD) as well as to determine the treatment efficiency of the ABR-MFC.

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Orientador: Glaucia Maria Pastore / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-13T13:08:43Z (GMT). No. of bitstreams: 1 Quadros_CedenirPereirade_D.pdf: 2098145 bytes, checksum: bb56ba34ac3fa84f3dc7493e47485a6d (MD5) Previous issue date: 2009 / Resumo: Na perspectiva de se tornar uma alternativa aos produtos já existentes para a indústria, foi proposto neste trabalho uma mistura inédita e original composta por uma lipase alcalina (LA) produzida por Fusarium oxysporum e biossurfatante (BS) produzido por Bacillus subtilis, a qual foi denominada de mistura LA/BS. O objetivo desta mistura foi remover materiais gordurosos de tecidos de algodão e de superfícies de aço inoxidável, assim como remover biofilmes de micro-organismos indesejáveis para a indústria de alimentos. Primeiramente, a mistura LA/BS foi submetida a uma caracterização e verificação da manutenção das propriedades individuais de cada composto quando submetida aos diferentes tratamentos físico-químicos. A lipase alcalina manteve sua atividade enzimática na presença de 0,0001 a 0,01% de biossurfatante. O tensoativo, na mistura LA/BS, manteve sua característica de reduzir a tensão superficial da água para valores em torno de 30 mN.m-1. Quando submetida a variações de temperatura (-4 a 30?C) por 24 h e de pH (6 a 10) por 48 h, a mistura LA/BS se mostrou bastante estável em suas propriedades, demonstrando um comportamento bastante semelhante ao encontrado na literatura. A concentração micelar crítica (CMC) do BS não foi alterada na presença da LA. A mistura não perdeu suas características frente a diversos sais inorgânicos (exceto pelo CuSO4 para LA e Fe3+ para o BS), agentes oxidantes, redutores, quelantes e preservantes de alimentos. Além disso, funcionou como um ótimo agente emulsificante na presença de diversos hidrocarbonetos e ?eos vegetais, apresentando um ?dice de emulsificação após 24 h (IE24) em torno de 60%. Subsequentemente, a lipase alcalina se apresentou mais estável frente a 0,1% de BS (98% de atividade residual) do que aos surfatantes sintéticos testados. Em seguida, avaliou-se a sua capacidade de remover azeite de oliva impregnado em tecidos de algodão em uma solução. Uma alíquota de 0,5 mg.ml-1 de LA foi capaz de remover 48% de gordura dos tecidos e 3 mg.ml-1 de BS cerca de 50%. A presença de 3 mg.ml-1 de BS no sistema contendo 0,5 mg.ml-1 de LA aumentou a remoção do azeite de oliva em 10%, demonstrando um efeito de sinergismo na mistura. Além disso, LA/BS teve um comportamento similar aos surfatantes alquil benzeno linear sulfonado (LAS) e o dodecil sulfato de sódio (SDS). Superfícies rígidas de aço inoxidável foram recobertas com diferentes tipos de gorduras como gordura suína, gordura de frango, manteiga e creme de leite como forma de simular situações vistas em frigoríficos e laticínios. A presença do BS e da mistura LA/BS, de uma forma geral, melhorou a remoção das gorduras presentes nas placas conforme aumenta a concentração dos compostos. A mistura LA/BS melhorou a remoção de gordura suína, de frango e de creme de leite em 30; 35,1 e 29%, respectivamente. A remo?o da manteiga foi a menos influenciada pelos detergentes. Como padrão de detergente foi utilizado o surfatante SDS na concentração de 1,5%. A atividade antimicrobiana da mistura LA/BS foi realizada por meio de ensaio quantitativo pela concentração inibitóia mínima (CIM). Entre todos os micro-organismos testados, somente Bacillus subtilis, Bacillus cereus e a Listeria innocua tiveram seus crescimentos afetados pela mistura. A bactéria B. cereus foi a mais sensível (CIM 0,013 mg.ml-1). Em adição, o efeito de sanitizantes contra L. innocua aderidas ao aço inoxidável foi determinado por contagem em placas. Este método demonstrou que a presença de biossurfatante ou da mistura melhorou a remoção das células aderidas em relação ao tratamento sem sanitizantes, reduzindo a contagem, em média, 0,97 log.cm-2. Entretanto, não houve diferença significativa entre os sanitizantes propostos e o detergente padrão SDS (p<0,05) / Abstract: Within the perspective of becoming an alternative to products already used in the industry, this study proposed an unprecedented and original mixture consisting of na alkaline lipase (AL) from Fusarium oxysporum and a biosurfactant (BS) from Bacillus subtilis, which will be called AL/BS mix. The aim of this mixture was to remove fatty residues from cotton fabrics and stainless steel surfaces, as well as to remove biofilms of undesirable microorganisms on rigid surface to food industry. Firstly, the AL/BS mix was submitted to a characterization to verify the preservation of each compound individual properties when submitted to different physical and chemical treatments. The AL kept its enzymatic activity in the presence of 0.0001 to 0.01% of biosurfactant. The tensoactive agent, in the AL/BS mix, kept its characteristic of reducing the superficial tension of aqueous solutions to values around 30 mN.m-1. When submitted to temperature (-4 to 30ºC for 24 h) and pH (6 to 10 for 48 h) variations, the AL/BS mix proved quite stable in its properties, showing a behavior very similar to the ones found in literature. The BS critical micelle concentration (CMC) did not change in AL presence. The mix did not lose its characteristics in the presence of several inorganic salts (except CuSO4 for AL and Fe3+ for BS), oxidizing, reducing, chelating and food preservative compounds. Apart from that, the AL/BS mix also proved an excellent emulsifying agent in the presence of several hydrocarbons and vegetable oils, showing emulsifying index around 60% after 24 h (EI24). Subsequently, the AL proved more stable in the presence of 0.1% BS (98% residual activity) than the tested synthetic surfactant, in the same concentrations. Next, the ability of the AL/BS mix to remove olive oil from cotton fabric in a solution was evaluated. The 0.5 mg.mL-1 AL managed to remove 48% of the oil from cotton fabrics and 3 mg.mL-1BS managed to remove approximately 50%. The presence of 3 mg.mL-1 BS in the system which contained 0.5 mg.mL-1 AL increased the olive oil removal by 10%, showing a synergy effect in the mixture. Apart from that, AL/BS mix had a similar performance to sodium linear alkyl benzene sulphonate (LAS) and sodium dodecyl sulphate (SDS) surfactants. Rigid stainless steel surfaces were covered with different types of fatty materials, such as pork fat, chicken fat, butter and whipped cream, to simulate situations existing in meat and dairy industries. The presence of BS and AL/BS mix, generally speaking, improved the fat removal from plates in pace with the increase of compounds concentration. The AL/BS mix improved the removal of pork and chicken fat, and whipped cream in 30, 35.1 and 29% respectively. Butter was the fat least influenced by detergents. Surfactant SDS concentration at 1.5% was used as detergent standard. This testing showed efficiency, sensitivity and it can be used to develop new formulations. The anti-microbial activity of AL/BS mix was carried out by minimum inhibitory concentration (MIC) quantitative assays. Among all tested microorganisms, only Bacillus subtilis, Bacillus cereus and Listeria innocua had their growth affected by the mixture. B. cereus bacteria was the most sensitive (MIC 0.013 mg.mL-1). Besides, the sanitizing effect against L. innocua that was attached to stainless steel was determined by plates counting. This assay proved that the presence of biosurfactant or the AL/BS mix improved the removal of adhered cells in relation to the treatment without sanitizers, reducing the count, in average, 0.97 log CFU.cm-2. However, there has not been a significant difference between the proposed sanitizers and the standard detergent SDS (p<0.05) / Doutorado / Doutor em Ciência de Alimentos

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-03-19T16:27:31Z No. of bitstreams: 1 THIANNE SILVA BATISTA - DISSERTAÇÃO PPGEQ 2016..pdf: 2177027 bytes, checksum: 65931e0e786c26d61bb005c1fd18e0f7 (MD5) / Made available in DSpace on 2018-03-19T16:27:31Z (GMT). No. of bitstreams: 1 THIANNE SILVA BATISTA - DISSERTAÇÃO PPGEQ 2016..pdf: 2177027 bytes, checksum: 65931e0e786c26d61bb005c1fd18e0f7 (MD5) Previous issue date: 2016-05-25 / Capes / O processo de separação por adsorção destaca-se como uma alternativa para minimizar os problemas de contaminação em recursos hídricos e revela uma abrangente aplicabilidade, devido principalmente à utilização de argilas como adsorventes. O presente trabalho teve como objetivo avaliar a capacidade de adsorção da argila atapulgita in natura e modificada com o sal quaternário de amônio, como adsorvente de efluentes oleosos sintéticos. Foram realizados planejamentos experimentais fatoriais 22, em que, tiveram como variáveis independentes, a concentração inicial do óleo presente no efluente e tempo de agitação do processo, e como variável resposta o percentual de remoção de óleo. Em seguida, o ensaio de remoção foi avaliado realizando um estudo de viabilidade do processo de adsorção, com a obtenção do mecanismo de adsorção por meio da cinética, como também, com a definição do modelo que descreve o processo de adsorção através da isoterma. Diante as caracterizações realizadas na argila atapulgita foi possível identificar com a Difratometria de raios X (DRX) que sua estrutura não favorece a um deslocamento na intensidade dos picos após o processo de organofilização, porém, com a Espectroscopia na região do infravermelho (FTIR) fica evidenciada a presença dos grupos orgânicos comprovando, assim, a inserção do sal na estrutura da atapulgita; com a Microscopia eletrônica de varredura (MEV) observou-se uma morfologia fibrosa da argila e a Fisissorção de N2 (Método de BET) indicou a presença de estrutura mesoporosa da atapulgita in natura e macroporosa da argila organofílica. Os ensaios de adsorção demonstrou que o processo de organofilização aplicada à atapulgita favoreceu o processo de adsorção, pois desempenhou 67,57% de remoção de óleo e uma capacidade de adsorção de 7,23 mg de óleo por grama de argila, na concentração inicial de 100 mg.L-1 de óleo e no tempo de agitação de 1 hora. Com a aplicação dos modelos teóricos observou-se um coeficiente de determinação R² = 0,98, indicando uma forte correlação da equação de segunda ordem na cinética de adsorção. Para isoterma de adsorção, verificou-se que a equação de Freundlich, Langmuir e da Sigmoide BiDR, ajustaram-se aos dados experimentais. / The process of adsorptive separation stands out as an alternative to minimize contamination problems in water and shows a broad applicability, mainly due to the use of clays as adsorbent. This study aimed to evaluate the adsorption capacity of natural and modified attapulgite clay, using this material as an adsorbent of synthetic oily wastewater. 22 factorial experimental designs were conducted, wherein, the initial concentration of oil present in the effluent and the stirring time were independent variables and the response variable was the oil removal percentage. Then, the removing test was evaluated by performing a feasibility study of the adsorption process, obtaining the adsorption mechanism through kinetics, as well as with the definition of the model which best describes the experimental data through the adsorption isotherm. From the characterizations performed with the attapulgite clay, it was identified with x-ray diffraction (XRD) that its structure does not favor a shift in the intensity of the peaks after the organophilization process, however, the spectroscopy in the infrared (FTIR) demonstrated the presence of the organic groups confirming the insertion of the salt in the attapulgite structure; furthermore, through scanning electron microscopy (SEM), it was observed a fibrous morphology of the clay and N2 physisorption (BET method) indicated the presence of mesoporous structure of natural attapulgite and macroporous of organoclay. Adsorption tests showed that the organophilization applied to attapulgite favored the adsorption process because a 67.57% removal of oil and an adsorption capacity of 7.23 mg of oil per gram of clay were obtained, with the initial concentration of 100 mg.L-1 oil and a stirring time of 1 hour. With the application of theoretical models, a coefficient of determination of R² = 0.98 was reached, indicating a strong correlation of the second-order equation in the adsorption kinetics. For adsorption isotherm, it was found that Freundlich, Langmuir and Sigmoid BIDR equations fitted the experimental data.