Two stages kinetics of municipal solid waste inoculation composting processes

Area of Science:

• Environmental Science
• Microbiology
• Waste Management

Background:

• Composting is a crucial process for managing municipal solid waste (MSW).
• Understanding the microbial kinetics is key to optimizing composting efficiency.
• Previous studies have explored various factors influencing composting, but detailed kinetic analysis across stages is needed.

Purpose of the Study:

• To analyze the microbial kinetics of municipal solid waste (MSW) composting in two distinct stages.
• To evaluate the impact of inoculation on the degradation rates and stability of the composting process.
• To develop kinetic equations simulating substrate degradation under controlled conditions.

Main Methods:

• Dividing the MSW composting process into two stages for analysis.
• Utilizing an advanced composting reactor under controlled environmental conditions.
• Applying microbial kinetic models to simulate substrate degradation rates and coefficients.

Main Results:

• The first stage of composting degradation rate is primarily controlled by microbial concentration, with inoculation significantly increasing rates (Run C: 15.671 g/(kg x h) vs. Control: 10.5 g/(kg x h)).
• The second stage's decomposition rate is governed by substrate concentration.
• Inoculation reduced the half-velocity coefficient (Km), indicating enhanced efficiency and stability, particularly in Run C.

Conclusions:

• Inoculation is an effective strategy for improving municipal solid waste (MSW) composting efficiency.
• Microbial kinetics analysis reveals distinct control mechanisms in different composting stages.
• Optimized kinetic parameters through inoculation lead to a more stable and efficient composting process.