Carbon dioxide emission control of a vermicompost process using fly ash

Area of Science:

• Environmental Science
• Soil Science
• Agricultural Science

Background:

• Composting and vermicomposting produce nutrient-rich products but release significant carbon dioxide (CO2), a greenhouse gas.
• Microbial and worm metabolism during vermicomposting contributes to atmospheric CO2 emissions.
• Controlling CO2 emissions while utilizing vermicompost is crucial for environmental sustainability.

Purpose of the Study:

• To investigate the efficacy of fly ash in controlling CO2 emissions from vermicomposting.
• To evaluate the potential of fly ash as a fertilizer for lettuce (Lactuca sativa) cultivation.
• To assess the dual role of fly ash in mitigating greenhouse gas and enhancing crop yield.

Main Methods:

• Different masses of fly ash (0.5, 1, and 1.5 kg) were introduced to a vermicomposting process to adsorb emitted CO2.
• CO2 concentrations in the air were monitored throughout the vermicomposting process.
• Lettuce (Lactuca sativa) was cultivated in soil amended with fly ash (10%) to assess its effect on plant growth.

Main Results:

• Fly ash significantly reduced CO2 concentrations, with adsorption percentages reaching up to 63.8% for 1.5 kg of fly ash.
• CO2 uptake capacities varied, with 1 kg of fly ash showing a capacity of 7.03 mmol CO2/g sorbent.
• Lettuce stem length increased significantly (22 cm) in soil with 10% fly ash compared to control (10.2 cm), showing a strong correlation (r=0.9817).

Conclusions:

• Fly ash is an effective adsorbent for mitigating CO2 emissions during vermicomposting.
• Fly ash application in soil significantly promotes the growth of lettuce (Lactuca sativa).
• Fly ash offers a promising solution for sustainable waste management and agricultural enhancement.