Sustainable options of post treatment of UASB effluent treating sewage: A review

Aerobic and Anaerobic Sewage Biodegradable Processes: The Gap Analysis

“…Besides, anaerobic system is cheaper, simple and flexible as compared to aerobic system which is high investment, operational and maintenance costs, labour intensive, complex infrastructure and high space requirement. Other advantages of anaerobic system are low consumption of energy, low nutrients and chemicals needed, great removal of contaminants especially for high COD (> 4000mg/L) even at low and high loading rates and production of energy gases such as methane ( figure 2) and no clogging experiences [3,9,13,14].In most cases, the anaerobic system is applied during pretreatment of high-strength organic sludge as this method is more economical and is well known as the primary source for effective wastewater management. Prior to discharge, the effluent from theanaerobic reactor will undergo post-treatment process under theaerobic condition to fulfill wastewater standard discharge requirement [15,16].…”

“…UASB reactor is a high rate anaerobic system that widely used in tropical countries which the sewage temperature is about 24 0 C to 27 0 C [4]. As reported in many studies, this system was successfully removed high COD from wastewater in warm climate countries [14,18,19].It consists of thesimple solid-liquid-gas separator (GSL separator); the most important part of the system at upflow velocities of 1 to 2 meter per hour (figure 3). The separator connects the well-mixed feature of reactor contact system to separate the gas, liquid and solid phases through mechanisms of an internal gas separation and clarification.…”

“…The system is popularly applied in tropical countries with thetemperature at 20 0 C to 30 0 C and at low to medium sewage strength [13,20]. This technology has been reported to be sustainable for treating domestic sewage in developing countries as well as in small communities [14]. However, fluctuation in temperature during winter and summer has caused changes to the sewage temperature which influenced the sludge quantity.…”

Efeitos do tempo de aeração no desempenho de reator de leito estruturado e aeração intermitente usado para remoção de matéria orgânica e nitrogênio de efluente de reator UASB

“…Dentre elas, identifica-se a produção de energia através do biogás, maior economia operacional, É reportada na literatura uma grande variedade de configurações de pós-tratamento com base em combinações com reatores UASB. Entre essas, filtro biológico, biofiltro aeróbio submerso, áreas alagadas (wetlands), reator em batelada sequencial, tratamento químico primário, tratamento em coluna de zeólitas, flotação por ar dissolvido e sistemas de aeração (Khan et al, 2011;Foresti et al, 2006). A Tabela 3.3 apresenta algumas características de avaliação de viabilidade econômica de algumas destas opções.…”

“…Cada situação deve ser analisada individualmente, com a constante preocupação de incorporar as especificidades locais na fase de investigação e decisão. A abertura de vários caminhos permite a busca por uma solução eficiente, econômica e sustentável, não só na fase de concepção, mas durante toda a vida operacional de uma estação de tratamento (Khan et al 2011). Neste contexto, o processo nitrificação e desnitrificação simultâneas (NDS) em reator de leito estruturado, explorado neste trabalho, surge como mais uma alternativa para o pós-tratamento de efluentes de reatores anaeróbios.…”