Influence of Aeration on Vermicomposting of Pre-Processed Vegetable Waste

Abstract

Objectives: Conventional vermicomposting process encroaches larger land area and time in the process. Keeping this as a core problem, an attempt was made to accelerate and digest the high volume of waste by modifying the conventional vermicomposting to engineered vermicomposting. Methods/Statistical Analysis: In the engineered process, the substrate depth was raised to a maximum of 30 cm with artificial aeration and elimination of pre-composting by pre-processing (chopping, pulverizing and stocking) the waste. The study also aimed at optimising the period of aeration in the system by experimenting with five different airflow periods (2, 4, 6, 8 and 10 hours) at a constant flow rate of 0.62 L/min. Findings: The outcome of this bench scale experimental study reveals that augmenting air will influence the waste digestion rate in vermicomposting. In addition, pre-processing the waste will eliminate the pre-composting process in vermicomposting and save considerable time. As per the χ2 statistics, the power equation fitted for cumulative substrate depth reduction (dcr) performsa good for all the aerated bins. The results revealed that 2 hours aeration was insufficient, while 6 -10 hours of aeration leads to quick reduction of moisture content in the substrate mass. Hence, four to six hours of aeration at a flow rate of 0.62 L/min per kg of pre-processed vegetable waste was found to be ideal. Application/Improvements: It was concluded from the experimental study, the vegetable waste volume could be considerably reduced (50% to 60%) by preprocessing it. Further the worm's digestion activity can be accelerated and engineered vermicomposting reduce both time and land requirement in the vermicomposting process.