TITLE:
Split Addition of Nitrogen-Rich Substrate at Thermophilic and Mesophilic Stages of Composting: Effect on Green House Gases Emission and Quality of Compost
AUTHORS:
Boakye Acheampong, Kodwo Miezah, Enoch Bessah, Benedicta Essel Ayamba, Francis Kemausour
KEYWORDS:
Compost, Nitrogen-Rich Substrate, Thermophilic, Mesophilic, Greenhouse Gas Emissions
JOURNAL NAME:
Open Journal of Soil Science,
Vol.14 No.2,
February
29,
2024
ABSTRACT: Composting
as a solution to the increasing generation of municipal solid waste (MSW), also
contribute to GHGs emission when not controlled and could lack some basic
nutrients, especially nitrogen. This study assessed the split-additions of
nitrogen-rich substrate to composting materials and their effect on GHGs
emissions as well as the quality of the composts. Nitrogen-rich substrates formulated
from pig and goat manure were co-composted with MSW for a 12-weeks period by
split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in
five different treatments. Representative samples from the compost were taken from each
treatment for physicochemical, heavy metals and bacteriological analysis.
In-situ CH4, CO2, N2O gas emissions were also
analyzed weekly during composting. It was observed that all the treatments
showed significant organic matter decomposition, reaching thermophilic temperatures
in the first week of composting. The absence affects the suitable agronomic
properties. All nitrogen-rich substrate applied at thermophilic stage
(Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97%
and 2.45%, respectively with highest nitrogen retention. In terms of GHG
emissions, CO2 was highest at the thermophilic stage when N-rich substrate was added in all treatment,
while CH4 was highest in the mesophilic stage with N-rich substrate
addition. N2O showed no
specific trend in the treatments. Split addition of the N-rich substrate for
co-composting of MSW produced compost which is stable,
has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich
substrate could be an option for increasing the fertilizer value of MSW
compost.