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In surface water nanofiltration (NF) for drinking water production, 15 to 25% of the feed is rejected by the membranes. Two complementary approaches are investigated in order to manage concentrates. On one hand, an additional NF stage allows an increase in the yield of drinking water production from 85 to 94%. Thirty-days filtration cycles are achieved. Conductivity, natural organic matter (NOM) and micropollutant contents of permeate fully satisfy drinking water standards. On the other hand removal of phosphonates, micropollutants and NOM is investigated in order to treat the concentrate before disposal. Phosphorus is removed by adsorption on pre-treatment sludge: removal reaches 82% with 100 ppm of suspended solids. To eliminate pesticides and NOM, adsorption on granular activated carbon (GAC) is studied with pilot scale fixed bed columns. Within 20 minutes contact time, selected pesticides are completely eliminated. NOM removal is approximately 30% with wood based GAC.

An unresolved question about the use of animal waste in agriculture is its effect on the physical and chemical attributes of soil, especially in commercial grain producing areas that have adopted direct seeding system (DSS). Aiming at contributing to the clarification of this question, we conducted a study in the mid-north region of the Mato Grosso state, Brazil, in a soybean and maize commercial area consolidated in DSS. Different doses of liquid swine manure (LSM) were applied and compared with NPK mineral fertilization. The aim of this study was to evaluate the physical and chemical quality of the soil and the productive potential of the soybean and maize crops under LSM doses and NPK fertilizer. Results indicated an increase in levels of K, P, Zn and Cu exchangeable with LSM fertilization of 80 m 3 .ha -1 . Fertilizers with mineral NPK and LSM at 80 and 60 m 3 .ha -1 , respectively, show soil porosity improvements and decreased soil penetration resistance. Moreover, the use of LSM also provided the highest increases in soybean and maize grain yield.Keywords: Glycine max L.; Zea mays L.; fertilizers; soil physics; soil fertility; direct sowing system. ResumoUma das questões pouco esclarecidas sobre o uso de resíduos animais na agricultura, é seu efeito sobre os atributos físicos e químicos do solo, principalmente em áreas comerciais produtoras de grãos que adotam o sistema de semeadura direta (DSS). Visando contribuir com o esclarecimento desta questão, realizamos um estudo na região médio-norte do estado de Mato Grosso, Brasil, em uma área comercial de soja e milho consolidada em DSS. Aplicou-se diferentes doses de dejetos líquidos de suínos (LSM) e as comparou com adubação mineral NPK. O objetivo foi avaliar a qualidade física e química do solo e o potencial produtivo das culturas soja e milho sob as doses de LSM e NPK como fertilizantes. Os resultados indicaram aumento nos teores de K, P, Zn e Cu trocáveis com adubação de 80 m3 ha-1 de LSM. As adubações com fertilizante mineral NPK e LSM nas doses de 80 e 60 m3 ha-1 proporcionam melhorias na porosidade do solo e diminuíram a resistência do solo à penetração. O uso de LSM também proporcionou os maiores incrementos na produtividade de grãos de soja e de milho. Palavras-chave:Glycine max L.; Zea mays L.; fertilizantes; física do solo; fertilidade do solo; sistema de semeadura direta.304

The response of crops to the application of biofertilizers in the soil is not yet well established. Therefore, we carried out this study with the objective of evaluating the productive potential of maize fertilized with doses of sewage sludge, comparing with the use of mineral fertilizer over four agricultural seasons. The experiment was conducted in a Red Dystroferric Nitosol (Ultisol) in a randomized block design and repeated measures in time. The treatments consisted of five doses of sewage sludge and one treatment using nitrogen, phosphorus and potassium in formulation. All fertilizations were carried out at maize sowing at four planting times (summer and 2nd crop of 1st agricultural year and, summer and 2nd crop of 2nd agricultural year) and replicates. The results showed a cumulative increase in the P, Ca, Mg and Zn leaf concentrations over the four seasons crops, when the sewage sludge was used in the 30 and 40 Mg ha-1 doses. However, reductions in plant height, weight and maize cob diameter, mass and grain yield were observed at the end of the last harvest. The treated sewage sludge is a viable alternative for maize fertilization in the first harvest, provides increases in grain yield in the order of 1.35 Mg ha-1 and can be recommended instead of NPK mineral fertilizers in built-up fertility soils.