Tratamento de efluente de abatedouro de tilápia com adição de manipueira na fase anóxica

Abstract

RESUMO:O objetivo deste trabalho foi avaliar a desnitrificação de efluente de abatedouro de tilápia, em reator em batelada. Para isto, foi avaliado o efluente gerado por uma indústria processadora de mandioca (manipueira) como fonte de carbono. Também foram avaliadas as condições de agitação do sistema. Os experimentos foram conduzidos em escala de laboratório, em que foram testados cinco níveis de agitação (20; 32; 60; 88 e 100 rpm) e cinco níveis de relação DQO/N (0,1; 1,0; 3,2; 5,4 e 6,3), configurando-se um planejamento do tipo Delineamento Composto Central Rotacional (DCCR), com quatro ensaios nos níveis +1 e -1; quatro ensaios nos níveis dos pontos axiais (-1,414 e +1,414) e mais uma triplicata no ponto central (0), totalizando 11 ensaios. Avaliaram-se o desempenho da desnitrificação através da remoção de nitrato (%) e a remoção de nitrito (%). Durante o processo, também foram monitorados temperatura (ºC), pH e alcalinidade (mgCaCO 3 .L -1 ). Os resultados mostraram que a relação DQO/N teve influência significativa, com intervalo de confiança de 95%, sobre o processo de remoção de nitrato e nitrito, com faixa ótima de operação entre 3,2 e 5,4, cujas eficiências de remoção de nitrogênio foram de 100%. PALAVRAS-CHAVE:remoção biológica, desnitrificação, nitrato, nitrito, efluente de abatedouro de peixe, efluente de fecularia. TREATMENT OF TILAPIA SLAUGHTERHOUSE WASTEWATER WITH ADDITION OF CASSAVA IN ANOXIC STAGEABSTRACT: The objective of this work was to evaluate the denitrification of tilapia slaughterhouse wastewater, in a batch reactor. For this, it was evaluated the wastewater from a cassava processing industry (manipueira) as a carbon source. It was also evaluated the shaking conditions of the process. The experiments were carried out in laboratory series, where five shaking levels were tested (20; 32; 60; 88 e 100 rpm) as well as five COD/N ratio levels (0.1; 1.0; 3.2; 5.4 and 6.3), forming a planning as a Central Composite Rotational Design (CCRD), with four essays in levels +1 and -1; four essays on the axial points levels (-1.414 and +1.414) and one more triplicate in the central point (0), which meant eleven essays. The denitrification performance through the nitrate removal (%) and nitrite removal (%) were evaluated. During this process, temperature (°C), pH and alkalinity (mgCaCO3.L-1) were also observed. The results showed that the COD/N ratio had significant influence, with a 95 % of confidence interval, on the process of nitrate and nitrite removal, with a great operation range, from 3.2 to 5.4, whose nitrogen removal efficiencies were 100 %.

Effect of Aeration and Recirculation in the Removal of Nitrogen and Chemical Oxygen Demand From Sanitary Sewage in a Structured Bed Reactor

“…Asadi et al (2016) also observed that TN removal in effluent from dairy and soft drink plants ranged from 39 to 72% when COD/N ratio ranged from 3 to 6.2. Kummer et al (2011) evaluated the denitrification of tilapia slaughterhouse effluent, and obtained 100% nitrate removal with a COD/N ratio between 3.2 and 5.4. With a C/N ratio greater than 5.4 and less than 3.2 denitrification efficiency decreased.…”

Influence of recirculation rate on the performance of a combined anaerobic-aerobic reactor applied to the removal of carbon and nitrogen from poultry slaughterhouse wastewater

“…Author(s) agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License such as the initial concentration of ammonia nitrogen, the carbon to nitrogen ratio, the air flow and the cycle time (Andrade et al, 2010;Kummer et al, 2011;Dallago et al, 2012;Mees et al, 2011;Lima, et al, 2014;Lopes, et al, 2015).…”

Production of natural aroma by yeast in wastewater of cassava starch industry

“…Residual liquid of cassava processing (Manihot esculenta Crantz) is generated in large volumes and researchers have studied it in biotechnological processes, such as volatile compounds production (DAMASCENO et al, 2003), in treatment of tilapia slaughterhouse effluent (KUMMER et al, 2011) and 2-Phenylethanol production (OLIVEIRA et al, 2013).…”