In this study, the impacts of reused and sucrose-decorated pumice as bulking agents on the composting of
sewage sludge were evaluated in the lab-scale reactor. The variations of temperature, pH, NH3 and CO2
emission rate, moisture content (MC), volatile solid, dissolved organic carbon, C/N and the water absorption
characteristics of pumice were detected during the 25 days composting. The MC of pumice achieved
65.23% of the 24 h water absorptivity within the first 2 h at the mass ratio of 0.6:1 (pumice:sewage
sludge). Reused pumice increased 23.68% of CO2 production and reduced 21.25% of NH3 emission. The
sucrose-decorated pumice reduced 43.37% of nitrogen loss. These results suggested that adding pumice
and sucrose-decorated pumice in sludge composting matrix could not only adjust the MC of materials,
but also improve the degradation of organic matters and reduce nitrogen loss.