| dc.description.abstract | The use of vacuum technology, applied to the area of sanitary sewage and effluents, is associated with studies of the properties of compaction and settlement of sludge and processes of degassing and/or removal of gases and/or determination of the quantity/quality of gases generated in aerobic and anaerobic treatment processes. However, there is a need for specific studies on the effect of vacuum application on biological treatment processes and their relationship with improvements in the quality of the treated effluent. From this, this research aimed to analyze the influence of the vacuum in the reduction of the organic load and of nutrients in the treatment of raw sanitary sewage. The research began with the study and development of a bench-scale vacuum chamber for system operation and analysis of the experimental configurations adopted through theoretical foundations and preliminary tests. The methodology was based on carrying out three experimental sequences (depending on temperature and pH variables) in two vacuum variations (40 kPA and 80 kPA) under two variations of vacuum exposure
time (30 and 60 minutes). The samples were analyzed for potential organic load removal (BOD, COD and TSS) and nutrient removal (NA, NTK and P). The obtained results suggest that the vacuum has influence in the reduction of the organic load and of nutrients in the raw sewage. Regarding the efficiency analysis regarding the removal of organic load, the reductions in BOD, COD and TSS ranged from nonexistent to 36.9%, from 9.3% to 32.1% and from 6.9% to 52.4 %, respectively. Regarding the analyzes regarding the efficiency in the reduction of NA, NTK and P, the removals ranged from 3.9% to 14.1%, 4.1% to 12.9% and from 12.2% to 31%, respectively. For BOD, COD and TSS analyses, the best operating conditions were VAT30 (vacuum of 40 kPa, period of 30 minutes and temperature of 40°C), VA60 (vacuum of 40 kPa for period of 60 minutes) and VBP30 (vacuum of 80 kPa, period of 30 minutes and pH change), respectively. For NA, NTK and P analyses, the best operating conditions were VB30 (80 kPa vacuum for 30 minutes), VB60 (80 kPa vacuum for 60 minutes) and VAP60 (40 kPa vacuum, period 60 minutes and pH change), respectively. | en |
