Performance evaluation of dewatering systems for bio-digestate for developing countries

Ajay Kumar  Jha; Sujan  Jojiju; Hari  Darlami; Bijay  Basnet

doi:10.59400/esc.v2i3.1431

Performance evaluation of dewatering systems for bio-digestate for developing countries

Ajay Kumar Jha Department of Mechanical and Aerospace Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University, Kathmandu 44600, Nepal
Sujan Jojiju Department of Mechanical and Aerospace Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University, Kathmandu 44600, Nepal
Hari Darlami Department of Mechanical and Aerospace Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University, Kathmandu 44600, Nepal
Bijay Basnet Department of Mechanical Engineering, Kathmandu University, Dhulikhel 45210, Nepal

Article ID: 1431

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DOI: https://doi.org/10.59400/esc.v2i3.1431

Keywords: screw type dewatering system; bio-digestate; performance evaluation; liquid yield; extraction efficiency

Abstract

The performance evaluation of a screw type dewatering system for bio-digestate in Nepal demonstrates significant potential for improving the usability and efficiency of bio-digestate as a fertilizer. Remarkable modifications in the previous include a 5 HP motor running at 1440 RPM with a gear reduction ratio of 1:40, a spring assembly system at the outlet, and a fine sieve. Testing and performance analysis at different operating speeds using a variable frequency drive revealed an optimal performance at 8 RPM, where the system achieved a liquid yield of 92.02% and an extraction efficiency of 73.12%. The installation cost of the machine was NPR 384,000, with a payback period of 2 years, six months, and two days. The internal rate of return (IRR) was calculated at 28.53%, while the net present value (NPV) was NPR 179,006.35. This study indicates that operating the dewatering system at lower speeds may improve efficiency and effectiveness in the dewatering process. This makes the machine a viable option for producing organic fertilizer and addressing Nepal’s significant need for fertilizer.

References

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Published

2024-07-19

How to Cite

Jha, A. K., Jojiju, S., Darlami, H., & Basnet, B. (2024). Performance evaluation of dewatering systems for bio-digestate for developing countries. Energy Storage and Conversion, 2(3), 1431. https://doi.org/10.59400/esc.v2i3.1431

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