2 resultados para Hermetic compressors

em Universidade Federal do Rio Grande do Norte(UFRN)


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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 m³) and two parallel anaerobic filters (36 m³ 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 m³/d) and different aeration conditions, are these: stage 01, when applied air flow of 0.01 m³ 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 m³ air/min; at last, at last, in stage 03, the air flow rate of first aerated filter was 0.10 m³ air/min and on the second remained at 0.01 m³ air/min. The filter FA1 received load of 0.41 kg COD/m³.d, 0.37 kg COD/m³.d and 0.26 kg COD/m³.d on phases 01, 02 and 03, respectively. The FA2 received loads of 0.25 kg COD/m³.d, 0.18 kg COD/m³.d and 0.14 kg COD/m³.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

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The present dissertation aims to an approach of the teaching of Portuguese language on television, trying to find how possible is the contribution of this communication media in the sense to give a higher classroom dynamism and to excite the students for that subject. The TV show Afinando a Língua (roughly, putting the language in tune ), a Canal Futura feature, have as one of these main purpose be shown on the classrooms as a tool that could enlarge the possibilities of a subject often took as particularly difficult. Blocked by the traditional grammatical teaching, the Portuguese lessons have been for years pictured as hermetic and far from the Brazilian speakers reality. So, people create myths around the language that earns adjectives as complicate and inaccessible and that Brazilians can t speak the Portuguese really good, because it only happens in Portugal, the original country of the language. These myths start exactly because the teaching orientation take their basis only on the standard language, in fact just one of the language variations by the way, anywhere in the world dictated by ancestral rules, once produced in Portugal. The regular school don t accept the Portuguese variation as a natural fact for a huge country as Brazil, with almost 190 million people, regarding it as a wrong way of talking. The repression that follows the students from the early school days make them repel the language supposedly learned at school. In fact, they normally face it as something unfamiliar, different from the language that they have use to learn at home, from the family and neighbors Instead of giving new possibilities for the language learning, the television, a powerful audiovisual device, only reinforces the idea that everyone, in any life situation, should talk the standard Portuguese, turning its back to the learning acquired much earlier that any person reach the school. This conservative attitude brings almost no changes, between the shows that try to teach the idiom and the traditional Portuguese lessons, wasting valuable tools that could lead to the possibility to open the classroom to the outside world, and to the wider knowledge of the differences from each Brazilian region culture, a positive attitude that could much enlarge the cultural and linguistic students universe