Enhancing hydrolysis and syntropy simultaneously in solid state anaerobic digestion: Digester performance and techno-economic evaluation

Kunwar Paritosh; Sanjay Mathur; Nidhi Pareek; Vivekanand Vivekanand

doi:10.1016/j.biortech.2021.125538

Enhancing hydrolysis and syntropy simultaneously in solid state anaerobic digestion: Digester performance and techno-economic evaluation

Bioresour Technol. 2021 Oct:338:125538. doi: 10.1016/j.biortech.2021.125538. Epub 2021 Jul 13.

Authors

Kunwar Paritosh¹, Sanjay Mathur², Nidhi Pareek³, Vivekanand Vivekanand⁴

Affiliations

¹ Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, Rajasthan 302017, India.
² Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, Rajasthan 302017, India.
³ Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan 305801, India.
⁴ Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, Rajasthan 302017, India. Electronic address: vivekanand.cee@mnit.ac.in.

PMID: 34274581
DOI: 10.1016/j.biortech.2021.125538

Abstract

The present study investigated the effect of alkali and biochar addition for simultaneous increment of hydrolysis and syntropy for higher methane yield from pearl millet straw (PMS) in solid state anaerobic digestion. A taguchi based design of experiment was coupled with grey relation analysis for multiple output optimization. Study showed that 0.5 g (g/100 g PMS) of alkali and 10 g/L of biochar was the optimised dosing. Statistically, contribution of biochar and alkali was 48 and 21% respectively on the multiple output. The confirmation test revealed that hydrolysis rate constant, k and total volatile fatty acid/alkalinity ratio for reactor having optimised conditions was 0.0521 d^-1 and 0.36 while for control, it was 0.0595 d^-1 and 0.76 respectively. Techno-economic assessment showed US$ 25,652 of net present value and 11.29% of internal rate of return. Sensitivity analysis showed that capital expenditure and methane yield was most sensitive to net present value.

Keywords: Hydrolysis; Methane; Syntropy; Taguchi; Techno-economic assessment.

MeSH terms

Anaerobiosis
Bioreactors*
Fatty Acids, Volatile
Hydrolysis
Methane*

Substances

Fatty Acids, Volatile
Methane