Conclusion
The study brings out the role of actors involved in open deg- radation of mixed OFMSW,
degradation pattern and the rate kinetics of waste degradation in open dumpsites. The mixed
organic matter lost moisture content rapidly during the early stages of degradation and the
degradation rate slowed down subsequently and stabilized. In such a degradation process 48%
of VS was degraded till the moisture content reached levels > 60% in the first 6 days of
degradation. After this, only 14% of VS was lost during 6–30 days of degradation period. The
result confirms the involvement of micro and meso + micro categories. Soil contact has no
significant effect (source of inoculum) on the rate of waste degradation. Across the
different categories, when the moisture content reaches 50–60%, there is a maximum level of
reduction of waste VS content. This reduction was greater in micro and meso + microorganism
categories. This suggested that longer such ‘appropriate’ moisture content is maintained,
greater is the involvement of microorganisms leading to enhanced biodegradation of the
organic fraction. There is a reduction in C, N, and H mass with the involvement of different
sizes
Table 2 Degradation pattern and rate kinetics of
different conditions
Details |
Organism |
|
|
Soil contact |
|
|
Micro |
Meso + micro |
|
NSC |
PSC |
SC |
VS0 (g/kg) |
180.727 |
180.727 |
|
176.331 |
176.331 |
176.331 |
Pattern |
y = 132.97e−0.0643x |
y = 132.58e−0.0629x |
|
y = 154.18e−0.0353x |
y = 170.43e−0.0582x |
y = 145.75e−0.0325x |
R2 |
0.8945 |
0.8468 |
|
0.8823 |
0.8396 |
0.724 |
Phase I |
|
|
|
|
|
|
Period (days) |
0–8 |
0–8 |
0–6 |
0–6 |
0–6 |
Kinetics |
Zero order |
Zero order |
Zero order |
Zero order |
Zero order |
K (g/kg/day) |
24.88584 |
22.75678 |
14.88066 |
15.7474013 |
16.60726 |
Phase II |
|
|
|
|
|
|
Period (days) |
8–30 |
8–30 |
6–30 |
6–30 |
6–30 |
Kinetics |
First order |
First order |
First order |
First order |
First order |
K (/day) |
0.049 |
0.075 |
0.036 |
0.03 |
0.024 |
of organisms and with different types of soil contact. Degra- dation of VS is an exponential
decay function during the first ‘moist’ period of decomposition and latter with first-order
rate kinetics when MSW dries in open dumpsites.
Acknowledgements The authors are grateful to
the Indian Institute of Science for infrastructure support. The authors would like to thank
Ms. Naqiyya J. for help in conducting experiments. The financial support for this study was
provided by the Bangalore City Corporation (Bruhat Bengaluru Mahanagara Palika, BBMP) and is
gratefully acknowledged.
Declarations
Conflict of interest The authors declare no potential conflict of interest
regarding the publication of this work. In addition, the ethical issues including
plagiarism, informed consent, misconduct, data fabrication and, or falsification, double
publication and, or submission, and redun- dancy have been completely witnessed by the
authors.