[Technology of sewage sludge treatment: methods for reduction of environment toxins in sludge and for adjustment of sludge quality for sludge utilization in non food or non feed producing soils]

aguas fecales cleaning contaminantes danemark denmark dinamarca environmental impact heavy metals impact sur l'environnement impacto ambiental limpieza lodos residuales metales pesados methode methods nettoyage polluant pollutants sewage sewage sludge technologie technology tecnologia uses usos utilisation waste disposal