IIT Guwahati researchers develop novel biowaste management method “minimizing biodegradation time”
22 Jan 2024 --- The Waste Management Research Group (WMRG) at the Indian Institute of Technology (IIT), Guwahati, has introduced a two-stage biodegradation technique that reportedly yields vermicompost in 27 days for urban waste management and reduces the waste volume by 71%, producing a nutrient-rich soil conditioner with 4.2% total nitrogen.
The approach combines Rotary Drum Composting (RDC) with Vermicomposting (RDVC). It has been optimized to address the challenges posed by municipal solid waste deposited in open dumpsites, which often contain over 50% organic material, generating substantial heat through long-term decomposition.
Professor Ajay S Kalamdhad, the lead researcher and head of the Department of Civil Engineering at IIT Guwahati, explains: “We optimized the RDC technique and combined it with RDVC to reduce biodegradation duration. The earthworms, Eisenia fetida, can acclimatize faster to partially degraded organic matter from the drum compost and produce vermicompost in just 27 days.”
The researchers detail that while RDC, capable of converting diverse organic feedstocks into nutrient-dense compost within 20 days, reduces the volume of municipal waste by 60-70%, it has limitations in terms of compost quality. Moreover, RDVC is said to be a superior biodegradation process requiring a minimum of 60 days but less adaptable for urban municipal corporations.
The two-stage biodegradation strategy developed by WMRG combines the strengths of both processes, overcoming these limitations. “The innovative process introduced by the Waste Management Research Group at IIT Guwahati has the potential to reshape organic waste treatment facilities globally, providing an environmentally compatible solution to mitigate contamination hazards and produce an outstanding soil conditioner,” shares the institute.
A new approach developed by IIT Guwahati researchers to assist the municipal corporations to manage organic waste (Image credit: Kalamdhad et. al.).
Nutrient-rich byproduct for agriculture
The two-stage composting technology has been transferred to The Apshisht Management and Environmental Research, a company based in the IIT Guwahati incubation center, to make the research findings accessible to end-users.
The microbial composition of the compost was analyzed through metagenomic analysis, ensuring the final product is non-toxic and safe. The researchers say the nutrient-rich soil conditioner, derived from waste, contains 4.2% total nitrogen, making it suitable for agricultural use.
The technique’s experimental verification was confirmed in laboratory and large-scale settings at the Solid Waste Laboratory of IIT Guwahati. The scaled-up process demonstrated the production of 100-150 kg of vermicompost within a month from 250-300 kg of daily waste fed, with the added benefit of an increased earthworm count resulting in the secondary end product being the earthworm itself.
“This proven technique not only handles sizable quantities of organic waste but also offers immediate application feasibility for municipal corporations, industries, sewage treatment facilities, aquatic weeds and various organic waste management sectors,” says Kalamdhad.
The research findings, co-authored by Suryateja Pottipati and Kalamdhad, have been published in journals such as the Journal of Biomass Conversion and Biorefinery, Journal of Environmental Management, Bioresource Technology and Waste Management.
Additionally, the resulting product — Mati Dhan Organic Vermicompost Fertilizer Manure for Plants — is available on online platforms such as Amazon and Indiamart, offering an environmentally sustainable solution for organic waste management.
Edited by Radhika Sikaria
