Biosolids management in Spain: A case study

The special interest of biosolids management in Spain is mainly due to the great increase in the amount of wastewater to be treated. This fact is related to the need to protect the environment and principally to the need to comply with the Directive of the European Communities on wastewater treatment and with other related regulations. In addition, the cost associated with the treatment and disposal of biosolids is also of capital concern as this represents around 50% of total wastewater treatment costs. Some data regarding the Spanish situation concerning sewage treatment and biosolids use and disposal are given. This reveals that all over the country biosolids management is quite different as many factors affecting biosolids processing and fate such as wastewater quality, treatment plant characteristics, local culture, land conditions and environmental awareness depend on the geographical area. The situation respecting wastewater treatment and biosolids management in Central Asturias, Spain is shown in greater detail, including the general findings of a couple of reports commissioned by the regional environmental authorities. These reports consisted, respectively, of a technical revision of a facility planned for the incineration of biosolids and a study of several alternatives for the treatment and disposal of biosolids in a particular area of the region.