Avaliação operacional da estação de tratamento de efluentes de uma indústria de papel

• Autor(a) principal: Brandão, Marina Domingos
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3836
• topic: Papel - Indústria; Processos de fabricação; Indústria da celulose - Papel; Lagoa aerada; Paper - Industry; Manufacturing processes; Industry cellulose - Paper; Aerated lagoon; CNPQ::ENGENHARIAS::ENGENHARIA SANITARIA::TRATAMENTO DE AGUAS DE ABASTECIMENTO E RESIDUARIAS

In the pulp and paper industry there is a large consumption of water in their processes which are directly linked to the issue of wastewater and characteristics of these effluents . Normally these industries treat their effluents by biological processes such as activated sludge and aerated lagoons . The treatment system aerated lagoons are classified as optional or complete mixing due to the power density of the aeration equipment . This study analyzes the performance of a complete-mix aerated lagoon followed by decantation pond of Santher paper mill located in Governador Valadares, Minas Gerais. Checks the current status of the treatment system with respect to flow, hydraulic detention time (HDT), power density, temperature and the availability of dissolved oxygen (DO) provided by nine aerators. The volumetric flow measurement method was used to determine a rate of 2419 m3/day, with corresponding and TDH's of 8.76 and 1.87 for the aeration and settling ponds, respectively. The temperatures did not exhibit large variations within each pond, the aerators indicated power density of 3.12 W/m3, a value close to the recommended minimum degree, and DO concentrations on the surface of the pond aeration above the recommended minimum, yet close the bottom of the pond, DO levels were observed in the range of 0 to 2.0 mg/L.. Physico-chemical characterization of the effluent was performed and compared to standards for effluent discharge in force in the State of Minas Gerais. Removal efficiencies of COD, BOD, TSS and oil and grease were 82%, 83%, 95% and 84%, respectively. Nitrogen and phosphorus were found in excess in the lagoons. The final effluent did not present acute toxicity to Daphnia similis or chronic toxicity to Ceriodaphnia dubia. The soluble COD removal coefficent for the complete mix aerated lagoon was estimated to be 0,23/day. Specific ultraviolet absorbance ( SUVA 254 ) of the effluent decreased at each stage of treatment, while UV 254 /UV 280 values remained constant throughout the system. The study also examined the occurrence of browning and odor generation in the settling pond, where the episodes were associated with lack of oxygen in the pond triggering anaerobic condition.