Este trabalho avaliou a eficácia do armazenamento de dejetos de suínos por 120 dias, em três esterqueiras de propriedades suinícolas localizadas na bacia do lajeado Suruvi, município de Concórdia, região oeste de Santa Catarina. Os parâmetros analisados foram: decomposição do material carbonáceo, transformação de compostos nitrogenados, adsorção do fósforo e viabilidade de microrganismos patogênicos. Os resultados revelaram que: a) as maiores remoções de material carbonáceo ocorrem entre 30 e 60 dias de armazenamento; b) o ambiente anaeróbio das esterqueiras impossibilitou as remoções de nitrogênio amoniacal por nitrificação/desnitrificação; c) embora as remoções de ortofosfato na fase líquida do dejeto tenham sido significativas, a estocagem por longo período parece favorecer a migração desse elemento para a fase sólida do resíduo, e d) ao longo dos 120 dias de armazenagem, não foi possível reduzir o NMP médio de coliformes (CF e CT), porém os valores remanescentes ainda são elevados, fato que dificulta a disposição do material.

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Santa Catarina State, southern Brazil, has the greatest swine breeding activities of Latin America. Generally, the piggery wastewater is treated in pond systems that are able to remove organic material according to local environmental legislation. However, these systems do not remove nitrogen and phosphorus efficiently. This work deals with a post-treatment system, using vertical flow constructed wetlands. The experiment was conducted in a swine production farm which has 45,000 animals. Although the pond system was able to partially remove the content of nutrients, their concentration in the effluent was high for environmental disposal. A four-bed vertical flow constructed wetland pilot plant, using Typha spp., was built. The pilot plant operated for 280 days for beds 2-4 (sand 2). However, the experiments with beds 1-3 (sand 1) were stopped after 111 days of operation, when a reduction in the wastewater drainage was observed. The beds with sand 2 showed a 33% COD removal, and about 49% of nitrification was observed from 111 days until the end of the operation. PO(4)-P removal was 45% with a loading rate of around 1.36 g m(-2) d(-1).

Results of polypropylene removal in injected metallic parts by using plasma technology are presented. The samples were injected with 55.18% Vol. of unalloyed iron powder, 23.57% Vol. of paraffin and 21.25% Vol. of polypropylene. The paraffin was previously removed in hexane bath, followed by a treatment in abnormal glow discharge of argon and hydrogen for the removal of the polypropylene. The electric discharge was generated in two configurations: a confined anode-cathode with the samples placed on the anode and a confined grid (anode)-cathode system with the sample placed on a holder at floating potential inside the grid. In the first geometry, electrons bombarded the sample surface, while in the second, they are collected by the grid. The samples were characterized by mass loss measurements and scanning electron microscopy. The results showed that the hydrogen discharge was more efficient for both configurations, which is attributed to the high reactivity of hydrogen atoms produced in the discharge. In addition, when plasma debinding was performed at 400 ºC for 10 min, by using the confined anode-cathode configuration, the polypropylene removal was total, while in the confined grid (anode)-cathode geometry the removal was approximately 32%. The higher polypropylene removing observed in the anode-cathode configuration is attributed to electron bombardment of the surface of the sample

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