Optimisation Study on the Production of Anaerobic Digestate Compost for Application on Arable Soils

Abstract

Organic fraction of municipal solid waste (OFMSW) is a rich substrate for biogas and compost production. Anaerobic Digestate compost (ADC) is an organic fertilizer produced from stabilized residuals of anaerobic digestion of OFMSW. This paper reports the result of studies carried out to optimise the production of ADC from organic fractions of domestic wastes and the effects of ADC amendments on soil quality. In general, ADC amended soils showed greater bioactivity and soil biomass compared to unamended soils. The diversity of soil community structures also increased with increasing ADC amendments with fungal populations showing greater variation than bacteria, suggesting that ADC amendment has greater impact on fungi than bacteria. It was found that seed germination in ADC amended soils increased with dilution and incubation time, suggesting that lower ADC application rates and longer lag periods between soil applications and planting can improve the benefits of ADC as an amendment for arable soil.

Keywords: Anaerobic digestion; anaerobic digestate compost; food waste; green waste, postaerobic digestion; soil quality