Gas phase dispersion in a natural porous medium (yard waste compost) was investigated as a function of gas flow velocity and compost volumetric water content using oxygen and nitrogen as tracer gases.
A hydrophilic membrane, hydraulically connecting the compost to a water chamber, maintained under vacuum, controlled the water content in the compost.
The water plants are not very suitable for composting because of their high water content.
The reactor design allowed easy manipulation of dissolved components in the liquid phase while controlling the unsaturated water content in the compost.
To date, various options have been reported for mitigating N2O emissions from manure composting, including the composting parameters modulation (e.g., C/N ratio, water content, pH), N2-fixing bacteria inoculation, and material amendments (Dias et al. 2010; Ogunwande et al. 2008; Pepe et al. 2013; Wang et al. 2013).
It may therefore be anticipated that addition of N to the composts in our study could have lengthened the active composting phase, although no leachates were produced from our composts as the water contents were not too excessive.
The water content of the composts was determined after drying at 105°C for 72 h.
Compost water-holding capacity was determined by measuring water content held against gravity in a filter-paper-lined funnel.
The compost was chosen because it has a very wide water content range and because it represents a wide range of porous media, including soils and biofilter media.
The results show that two FTCs have effect on the methane removal of compost biocover as well as influence the evolution of the volumetric water content, temperature, settlement, gas composition and organic content of the biocover.
