Nitrifica??o de efluentes de reatores anaer?bicos em filtros submersos aerados

• Main Author: Ara?jo, Raulyson Ferreira de
• Other Authors: CPF:05712939487
• Format: Others
• Language: Portuguese
• Published: Universidade Federal do Rio Grande do Norte 2014
• Subjects: Esgoto Sanit?rio; Filtros Biol?gicos; Aera??o; Nitrifica??o; Sewage; Biological filters; Aeration; Nitrification; CNPQ::ENGENHARIAS::ENGENHARIA SANITARIA
• Online Access: http://repositorio.ufrn.br:8080/jspui/handle/123456789/15967

Made available in DSpace on 2014-12-17T15:03:24Z (GMT). No. of bitstreams: 1 RaulysonFA_DISSERT.pdf: 2784918 bytes, checksum: f9eec0ac84786bd83f2f7e5f5d700dcc (MD5) Previous issue date: 2009-11-06 === Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior === Although the good performance in organic matter and suspended solids removal, the anaerobic reactors are unable to remove ammonia nitrogen from sewage, which makes indispensable to include a step of post-treatment for removal of ammonia or nitrate as necessary. This paper presents the performance of a new variant technology, where the nitrification unit, preceded by anaerobic units, is a submerged aerated biological filter, without continuous sludge discharge in their daily operation. The oxygenation system is very simple and inexpensive, consisting of perforated hoses and compressors. The anaerobic reactors are a septic tank with two chambers followed (8.82 m?) and two parallel anaerobic filters (36 m? each) filled with ceramic bricks and conics plastic parts. Both followed aerated filters were filled with cut corrugated conduit. The study evaluated the behavior of the system with constant domestic sewage flow (10 m?/d) and different aeration conditions, are these: stage 01, when applied air flow of 0.01 m? air/min in both aerated filter; stage 02, remained in the initial air flow rate in the second aerated filter and increased at the first to 0.05 m? air/min; at last, at last, in stage 03, the air flow rate of first aerated filter was 0.10 m? air/min and on the second remained at 0.01 m? air/min. The filter FA1 received load of 0.41 kg COD/m?.d, 0.37 kg COD/m?.d and 0.26 kg COD/m?.d on phases 01, 02 and 03, respectively. The FA2 received loads of 0.25 kg COD/m?.d, 0.18 kg COD/m?.d and 0.14 kg COD/m?.d on phases 01, 02 and 03, respectively. During stage 01, were found the following results: 98% removals of BODtotal and 92% of CODtotal, with effluent presenting 9 mg/L of BODtotal final average and 53 mg/L of CODtotal average; suspended solids removals of 93%, with a mean concentration of 10 mg/L in the final effluent; 47% reduction of ammonia of FA2 to FAN 's, presenting average of 28 mg NNH3/ L of ammonia in the effluent with; the dissolved oxygen levels always remained around 2.0 mg/L. During stage 02, were found removals of 97% and 95% to BODtotal and suspended solids, respectively, with average final concentrations of 8 and 7 mg/L, respectively; was removed 60% of ammonia, whose final concentration was 16.3 mg NNH3/ L, and nitrate was increased to a final average concentration of 16.55 mg N-NO3/L. Finally, the stage 03 provided 6 mg/L of DBOtotal (98% removal) and 23 mg/L of CODtotal (95% removal) of final effluent concentrations average. At this stage was identified the higher ammonia oxidation (86%), with final effluent showing average concentration of 6.1 mg N-NH3/L, reaching a minimum of 1.70 mg N-NH3/L. In some moments, during stage 03, there was a moderate denitrification process in the last aerated filter. The average turbidity in the effluent showed around 1.5 NTU, proving the good biomass physical stability. Therefore, the results demonstrate the submerged biological filters potential, filled with high void ratio material (98%), and aerated with hoses and compressor adoption, in the carbonaceous and nitrogenous matter oxidation, also generating an effluent with low concentration of solids === Apesar de bom desempenho no tocante ? remo??o de mat?ria org?nica e s?lidos suspensos, os reatores anaer?bios s?o incapazes de remover nitrog?nio amoniacal dos esgotos, o que torna indispens?vel a inclus?o de uma etapa de p?s-tratamento para a remo??o da am?nia ou do nitrato, sempre que necess?rio. Neste trabalho ? apresentado o desempenho de uma nova variante tecnol?gica, em que a unidade de nitrifica??o, precedida por unidades anaer?bias, ? um filtro biol?gico submerso aerado, sem cont?nuas descargas de lodo em sua opera??o cotidiana. O sistema de oxigena??o ? muito simples e de baixo custo, constitu?do por mangueiras perfuradas e compressores. Os reatores anaer?bios s?o um decanto-digestor de duas c?maras em s?rie (8,82 m?) e dois filtros anaer?bios em paralelo (cada um com 3,36 m?) preenchidos com tijolo cer?mico e pe?as pl?sticas c?nicas. Os dois filtros aerados, em s?rie, foram preenchidos com eletrodutos corrugados cortados. No estudo avaliou-se o comportamento do sistema com vaz?o de esgoto dom?stico constante (10 m?/d) e diferentes condi??es de aera??o, quais sejam: fase 01, quando se aplicou vaz?o de 0,01 m? ar/min nos dois filtros aerados; fase 02, manteve-se a vaz?o inicial no segundo filtro aerado e aumentou a do primeiro para 0,05 m? ar/min; por fim, na fase 03, a vaz?o do primeiro filtro aerado foi 0,10 m? ar/min e a do segundo permaneceu ainda em 0,01 m? ar/min. O filtro FA1 recebeu carga de 0,41 kg DQO/m?.d, 0,37 kg DQO/m?.d e 0,26 kg DQO/m?.d nas fases 0,1, 02 e 03, respectivamente. O FA2 recebeu cargas de 0,25 kg DQO/m?.d, 0,18 kg DQO/m?.d e 0,14 kg DQO/m?.d nas fases 01, 02 e 03, respectivamente. Durante a fase 01, foram observados os seguintes resultados: remo??es de 98% de DBOtotal e 92% de DQOtotal, com efluente apresentando DBOtotal m?dia final de 9 mg/L e DQOtotal m?dia de 53 mg/L; remo??o em torno de 93% de s?lidos suspensos, com concentra??o m?dia de 10 mg/L no efluente final; redu??o de 47% de am?nia do FA2/FAN s, apresentando am?nia no efluente final com m?dia de 28 mg N-NH3/L; os n?veis de oxig?nio dissolvido sempre mantiveram-se em torno de 2,0 mg/L. Durante a fase 02, foram verificados para DBOtotal e s?lidos suspensos remo??es de 97% e 95%, respectivamente, com concentra??es finais m?dias de 8 e 7 mg/L, respectivamente; o nitrog?nio amoniacal foi removido em 60%, cuja concentra??o final foi de 16,3 mg N-NH3/L, e o nitrato foi incrementado para uma concentra??o m?dia final de 16,55 mg N-NO3 -/L. Por fim, a fase 03 proporcionou efluente com concentra??es finais m?dias de 6 mg/L de DBOtotal (remo??o de 98%) e 23 mg/L de DQOtotal (remo??o de 95%). Nesta fase foi identificada a maior oxida??o de nitrog?nio amoniacal (86%), com efluente final apresentando concentra??o m?dia de 6,1 mg NNH3/ L, chegando a alcan?ar m?nimo de 1,70 mg N-NH3/L. Em alguns momentos, na fase 03, verificou-se um moderado processo de desnitrifica??o no ?ltimo filtro aerado. A turbidez m?dia no efluente final se mostrou da ordem de 1,5 NTU, comprovando a boa estabilidade f?sica da biomassa. Portanto, os resultados demonstram o potencial dos filtros biol?gicos submersos, preenchidos com material de elevado ?ndice de vazios (98%), e aerados com uso de mangueiras e compressor, na oxida??o de mat?ria carbon?cea e nitrogenada, gerando tamb?m um efluente com baixa concentra??o de s?lidos