Anaerobic digestion of residual municipal solid waste using biological–mechanical pre-treatment: the plant of Varennes Jarcy

Residual municipal solid wastecan be treated by anaerobic digestionafter a sortingprocess in order to remove the unwanted materials. After a mechanical sortingthe quality of the final compost can hardly cope with requirements for agriculture use. In this way, a more efficient sortingprocess using a specific equipment that provides a combined biological and mechanical effect, has been implemented on the plant of Varennes Jarcy prior to anaerobic digestion. This paper presents the main results obtained on this plant. The reduction of biodegradable organics in particle lower than 10 mm allows a very efficient separation by screening. An additional ballistic sortingremoves the remaining glass. The composition of the resulting sortedwaste was close to a source- sortedorganic fraction. The sortedwaste exhibit methane yields comparable with raw biodegradable organics, showing that the pre-treatment had little impact on anaerobic digestionperformance.