TY - JOUR
T1 - Effect of feed slurry dilution and total solids on specific biogas production by anaerobic digestion in batch and semi-batch reactors
AU - Jeppu, Gautham P.
AU - Janardhan, Jayalal
AU - Kaup, Shivakumara
AU - Janardhanan, Anish
AU - Mohammed, Shakeib
AU - Acharya, Sharath
N1 - Funding Information:
The authors would like to thank Prof. SVSR Krishna Bandaru, Prof. Balakrishna Prabhu, Prof. Harishkumar, Dr. Nethaji S., Ms. Sneha Ramesh, Mr. Sadananda Tendulkar, and all their colleagues. The authors also thank Dr. Arunkumar Thalla, Dr. Pruthviraj, Mr. Manohar Shanubogue, Mr. Sanjeev, Ms. Adhira, and Dr. Uma Shaktivel from the Civil Engineering Department of NITK., Surathkal. Also, the authors thank Dr. Bhasker Jha, and Prof.?V.K. Vijaykumar of CRDT in IIT. Delhi. The authors would like to thank Mr. Himanshu, Ms. Ivy (exchange scholar), Mr. Ankit Shettty, Mr. Siddarth Mitra, Mr. Kevin Lobo, Mr. Amitabh Roy, Mr. Nikil, Mr. Kripesh, Ms. Aspha Mohanty?and Mr. Mubeen for the help in experiments. The authors would like to thank the Karnataka Government and the Vision group on science and Technology (RGS/F GRD 696) for funding this work. The authors also thank the Karnataka state council state for science and technology (KSCST) for the funding (Grant No. 41S_B_BE_099 SPP-Biofuels). The authors also thank the anonymous reviewers for their suggestions which greatly improved the manuscript.
Funding Information:
The authors would like to thank Prof. SVSR Krishna Bandaru, Prof. Balakrishna Prabhu, Prof. Harishkumar, Dr. Nethaji S., Ms. Sneha Ramesh, Mr. Sadananda Tendulkar, and all their colleagues. The authors also thank Dr. Arunkumar Thalla, Dr. Pruthviraj, Mr. Manohar Shanubogue, Mr. Sanjeev, Ms. Adhira, and Dr. Uma Shaktivel from the Civil Engineering Department of NITK., Surathkal. Also, the authors thank Dr. Bhasker Jha, and Prof. V.K. Vijaykumar of CRDT in IIT. Delhi. The authors would like to thank Mr. Himanshu, Ms. Ivy (exchange scholar), Mr. Ankit Shettty, Mr. Siddarth Mitra, Mr. Kevin Lobo, Mr. Amitabh Roy, Mr. Nikil, Mr. Kripesh, Ms. Aspha Mohanty and Mr. Mubeen for the help in experiments. The authors would like to thank the Karnataka Government and the Vision group on science and Technology (RGS/F GRD 696) for funding this work. The authors also thank the Karnataka state council state for science and technology (KSCST) for the funding (Grant No. 41S_B_BE_099 SPP-Biofuels). The authors also thank the anonymous reviewers for their suggestions which greatly improved the manuscript.
Publisher Copyright:
© 2021, The Author(s).
PY - 2022/1
Y1 - 2022/1
N2 - Biomass from various sources such as cow dung is a significant source of renewable energy (as biogas) in many regions globally, especially in India, Africa, Brazil, and China. However, biogas production from biomass such as cattle dung is a slow, inefficient biochemical process, and the specific biogas produced per kg of biomass is relatively small. The improvement of specific biogas production efficiency using various dilution ratios (and, hence, total solids [TS]) is investigated in this work. A wide range of feed dilution (FD) ratios of cow dung: water (CD: W) was tested in batch biogas digesters with total solids ranging from 1% to 12.5% and FD ratio ranging from 2:1 to 1:20. To further verify the results from the above batch experiments, semi-batch experiments representative of field-scale biodigesters were conducted. Semi-batch reactors have a steady-state process, unlike batch reactors, which have an unsteady state process. Our results suggested that specific biogas production (mL/g VS) increased continuously when the total solids decreased from 12.5% to 1% (or when dilution increased). Our experiments also indicate that the commonly used 1:1 feed dilution ratio (TS ~ 10% for cow dung) does not produce the maximum specific biogas production. The possible reason for this could be that anaerobic digestion at higher total solids is rate limited due to substrate inhibition, mass transfer limitations, and viscous mixing problems that arise at higher total solids concentration. Hence, a higher feed dilution ratio between 1:2 and 1:4 (TS between 4 and 6.7%) is recommended for a more efficient biomass utilization of cowdung. Empirical relationships were also developed for variation of specific biogas yield with the total solids content of the cow dung slurry. Graphic abstract: [Figure not available: see fulltext.]
AB - Biomass from various sources such as cow dung is a significant source of renewable energy (as biogas) in many regions globally, especially in India, Africa, Brazil, and China. However, biogas production from biomass such as cattle dung is a slow, inefficient biochemical process, and the specific biogas produced per kg of biomass is relatively small. The improvement of specific biogas production efficiency using various dilution ratios (and, hence, total solids [TS]) is investigated in this work. A wide range of feed dilution (FD) ratios of cow dung: water (CD: W) was tested in batch biogas digesters with total solids ranging from 1% to 12.5% and FD ratio ranging from 2:1 to 1:20. To further verify the results from the above batch experiments, semi-batch experiments representative of field-scale biodigesters were conducted. Semi-batch reactors have a steady-state process, unlike batch reactors, which have an unsteady state process. Our results suggested that specific biogas production (mL/g VS) increased continuously when the total solids decreased from 12.5% to 1% (or when dilution increased). Our experiments also indicate that the commonly used 1:1 feed dilution ratio (TS ~ 10% for cow dung) does not produce the maximum specific biogas production. The possible reason for this could be that anaerobic digestion at higher total solids is rate limited due to substrate inhibition, mass transfer limitations, and viscous mixing problems that arise at higher total solids concentration. Hence, a higher feed dilution ratio between 1:2 and 1:4 (TS between 4 and 6.7%) is recommended for a more efficient biomass utilization of cowdung. Empirical relationships were also developed for variation of specific biogas yield with the total solids content of the cow dung slurry. Graphic abstract: [Figure not available: see fulltext.]
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U2 - 10.1007/s10163-021-01298-1
DO - 10.1007/s10163-021-01298-1
M3 - Article
AN - SCOPUS:85115223009
SN - 1438-4957
VL - 24
SP - 97
EP - 110
JO - Journal of Material Cycles and Waste Management
JF - Journal of Material Cycles and Waste Management
IS - 1
ER -
