Hydrogen Peroxide Effects on Composting and Its Use in Assessing the Degree of Maturity

Abstract

In a series of laboratory-scale experiments using adiabatic reactors, addition of hydrogen peroxide to the compost was shown to exert a triggering effect on the composting process. On treatment with hydrogen peroxide, the temperature in the composting mass rose at a significantly faster rate and reached higher levels compared to the control trials. Triggering effects similar in response were observed in all trials performed so far, using a variety of substrates. The initial rise of temperature may be attributed to exothermic non-biological chemical reactions. The subsequent long-term rise, however, is considered to reflect intensification of microbiological activity in the catabolic processes, as indicated by control experiments using an antimicrobial agent (toluene).

The intensity of the triggering effect of the hydrogen peroxide treatment appears to depend on the hydrogen peroxide concentration, the substrate’s moisture and its degree of decomposition, with fresh composts exhibiting a sharper temperature boost compared to stable ones. This property could be used for the assessment of the maturity/stability degree of composts, in a more sensitive modification of the self-heating test. A new thermal stability index (TSI) is proposed which could offer valuable information on energy balance and state of composting, especially if used in combination with respirometry to provide a calorimetric: respiration ratio in presence and absence of hydrogen peroxide.