| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 8.59 MB | Adobe PDF |
Authors
Advisor(s)
Abstract(s)
O presente trabalho tem como objetivo o estudo do processo de tratamento da estação de tratamento de águas residuais (ETAR) da empresa H.B. Fuller Portugal Produtos Químicos, S.A., construída em 1999. As colas produzidas na empresa foram sofrendo alterações e, consequentemente o efluente a tratar também mudou as suas características. Além disso, a empresa fabrica uma grande variedade de produtos. Este estudo começou por uma caracterização das águas residuais geradas ao longo das várias fases do processos de tratamento, tendo-se concluído que numa primeira abordagem deveria otimizar-se o tratamento primário. Os parâmetros analisados no efluente da ETAR antes e após tratamento para avaliação da sua eficiência, incluem pH, condutividade, turvação, carência química de oxigénio (CQO), carbono orgânico total (COT), azoto total e ferro. Os últimos dois parâmetros foram selecionados devido aos resultados obtidos nas análises externas realizadas anteriormente que revelavam que estes se encontravam acima do valor limite de emissão. Realizaram-se testes com sete coagulantes e quatro floculantes pelo método Jar-Test. O intuito foi avaliar se o conjunto coagulante/ floculante que se encontrava a ser utilizado pela empresa estava a ser aplicado nas melhores condições de dosagens e pH e também se existem opções de coagulante/ floculante que tratem a água residual de forma mais eficiente. O coagulante Kemira PAX 18 e o floculante Aquaprox MFA 9722 relevaram ser o conjunto com a relação de eficiência e custo (1,46 €/m3 ) mais adequada para se utilizar no tratamento da ETAR da empresa H.B. Fuller. Comparativamente com o efluente industrial sem tratamento, o teor de carbono orgânico total foi removido em 68% e a turvação em 99,7%. O azoto diminuiu 37% após tratamento, mas mesmo assim continuava acima do VLE (90 mg/L) permitido pela liçenca de descarga da empresa no coletor Municipal, mas como se trata de um tratamento primário o efluente teria de continuar a ser tratado. Os resultados de ferro foram baixos (0,37 mg Fe/L) e o pH encontrava-se na gama de 5,5 a 9,5 prevista para a descarga de água residuais no Regulamento n.º 586/2010, de 7 de julho da Indaqua. Realizaram-se testes em linha e os resultados foram uma boa separação e um sobrenadante límpido, como esperado. E, por causa do futuro aumento produtivo, testou-se também o conjunto coagulante/ floculante no efluente proveniente das colas base aquosa e os resultados foram positivos, sobrenadante límpido, flocos de tamanho médio e lama sedimentada. Assim sendo, concluiu-se que mesmo alterando a composição do efluente que chega à ETAR para tratamento, o Kemira PAX 18 e o Aquaprox MFA 9722 irão tratar o efluente de forma eficaz. Ao longo deste trabalho encontraram-se algumas sugestões de melhoria para tornar o tratamento mais eficaz como a adição de um pré-tratamento constituído pelas etapas de gradagem, tamisagem e flutuação, um doseador de antiespuma automático e de uma solução de acerto de pH ácida. Dado que a produção de lamas no tratamento de água é inevitável, estudaram-se ainda os possiveis destinos para a gestão e valorização das mesmas. Sugere-se a sua incineração para produção de energia térmica. Com o intuito de automatizar o processo de tratamento e adequar as técnicas disponíveis de tratamento pediu-se auxílio à empresa VentilAQUA que confirmou algumas das alterações sugeridas e adicionou mais algumas alterações ao longo do tratamento.
The present work aims to study the treatment process of the wastewater treatment plant (WWTP) of the company H. B. Fuller, Portugal Produtos Químicos, S. A.. The WWTP remains practically unchanged since 1999, the year when it was built. Since then, the glues produced in the company have undergone changes and, consequently, the effluent to be treated has also changed its characteristics. The company manufactures a wide variety of products. This study began with a characterization of the wastewater generated throughout the various stages of the processes, having concluded that in a first approach the primary treatment should be optimized. The parameters analysed in the WWTP effluent before and after treatment to evaluate their efficiency, include pH, conductivity, turbidity, chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen, and iron. The last two parameters were selected in this work due to the results obtained in the previous analyses that that revealed that they were above the emission limit value. Tests were conducted with seven coagulants and four flocculants by the Jar-Test method. The purpose was to evaluate if the coagulant/flocculant set to be used in the company was being applied under the best dosage and pH conditions, and if there are coagulant/flocculant options that treat wastewater more efficiently. The coagulant Kemira PAX 18 and the flocculant Aquaprox MFA 9722 proved to be the most cost-effective (1,46 €/m3 ) combination to be used in the treatment of the H.B. Fuller WWTP. Compared to the untreated industrial effluent, the total organic carbon content was removed by 68% and turbidity by 99.7%. Nitrogen, with the addition of the coagulant and flocculant, was reduced by 37% after treatment, but was still above the ELV (90 mg/L) allowed by the company's discharge into the municipal collector but since it is a primary treatment the effluent would have to be further treated. The results for iron were low (0.37 mg Fe/L) and the pH was in the range of 5.5 to 9.5 foreseen for the discharge of wastewater in Regulation no. 586/2010, of 7 July of Indaqua. In-line tests were performed, and the results were a good separation and a clear supernatant, as expected. And, because of the future production increase, the coagulant/flocculant set was also tested in the effluent from the water-based glues and the results were positive, clear supernatant, mediumsized flakes and sedimented sludge. Therefore, it was concluded that even changing the composition of the effluent arriving at the WWTP to be treated, Kemira PAX 18 and Aquaprox MFA 9722 will effectively treat the effluent. Throughout this work some suggestions for improvement were found to make the treatment more efficient such as the addition of a pre-treatment consisting of the stages of screening, sieving and flotation, an automatic antifoam dispenser and an acid pH adjustment solution. Since the production of slands in water treatment is inevitable, the possible destinations for their management and valorization were also studied. The application that should become the destination of the WWTP sludge is its incineration to produce thermal energy. In order to automate the treatment process and adapt the available treatment techniques, the company asked VentilAQUA for help. They confirmed some of the suggested changes and added some more changes throughout the treatment.
The present work aims to study the treatment process of the wastewater treatment plant (WWTP) of the company H. B. Fuller, Portugal Produtos Químicos, S. A.. The WWTP remains practically unchanged since 1999, the year when it was built. Since then, the glues produced in the company have undergone changes and, consequently, the effluent to be treated has also changed its characteristics. The company manufactures a wide variety of products. This study began with a characterization of the wastewater generated throughout the various stages of the processes, having concluded that in a first approach the primary treatment should be optimized. The parameters analysed in the WWTP effluent before and after treatment to evaluate their efficiency, include pH, conductivity, turbidity, chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen, and iron. The last two parameters were selected in this work due to the results obtained in the previous analyses that that revealed that they were above the emission limit value. Tests were conducted with seven coagulants and four flocculants by the Jar-Test method. The purpose was to evaluate if the coagulant/flocculant set to be used in the company was being applied under the best dosage and pH conditions, and if there are coagulant/flocculant options that treat wastewater more efficiently. The coagulant Kemira PAX 18 and the flocculant Aquaprox MFA 9722 proved to be the most cost-effective (1,46 €/m3 ) combination to be used in the treatment of the H.B. Fuller WWTP. Compared to the untreated industrial effluent, the total organic carbon content was removed by 68% and turbidity by 99.7%. Nitrogen, with the addition of the coagulant and flocculant, was reduced by 37% after treatment, but was still above the ELV (90 mg/L) allowed by the company's discharge into the municipal collector but since it is a primary treatment the effluent would have to be further treated. The results for iron were low (0.37 mg Fe/L) and the pH was in the range of 5.5 to 9.5 foreseen for the discharge of wastewater in Regulation no. 586/2010, of 7 July of Indaqua. In-line tests were performed, and the results were a good separation and a clear supernatant, as expected. And, because of the future production increase, the coagulant/flocculant set was also tested in the effluent from the water-based glues and the results were positive, clear supernatant, mediumsized flakes and sedimented sludge. Therefore, it was concluded that even changing the composition of the effluent arriving at the WWTP to be treated, Kemira PAX 18 and Aquaprox MFA 9722 will effectively treat the effluent. Throughout this work some suggestions for improvement were found to make the treatment more efficient such as the addition of a pre-treatment consisting of the stages of screening, sieving and flotation, an automatic antifoam dispenser and an acid pH adjustment solution. Since the production of slands in water treatment is inevitable, the possible destinations for their management and valorization were also studied. The application that should become the destination of the WWTP sludge is its incineration to produce thermal energy. In order to automate the treatment process and adapt the available treatment techniques, the company asked VentilAQUA for help. They confirmed some of the suggested changes and added some more changes throughout the treatment.
Description
Keywords
Coagulação-floculação Estação de Tratamento de Águas Residuais Otimização Tratamento primário Coagulation-floculation Wastewater Treatment Plant Optimization Primary treatment