Methane production from anaerobic co-digestion of sewage sludge and decanter cake
Increased production of sewage sludge from wastewater treatment and decanter cake from palm oil mill industry results in the generation of large quantities of solid waste. These wastes can cause environmental pollution and can give bad impact on human lifestyle. Sewage sludge can produce methane...
Saved in:
| Main Author: | |
|---|---|
| Format: | Thesis |
| Language: | English |
| Published: |
2021
|
| Subjects: | |
| Online Access: | http://psasir.upm.edu.my/id/eprint/104141/1/NORSHAFIQAH%20-%20IR.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Increased production of sewage sludge from wastewater treatment and decanter
cake from palm oil mill industry results in the generation of large quantities of
solid waste. These wastes can cause environmental pollution and can give bad
impact on human lifestyle. Sewage sludge can produce methane gas at a very
minimum rate of production. Co-digestion with decanter cake which content high
of carbon can increase methane gas production. In this research, an anaerobic
co-digestion has been considered to convert these organic pollutants into
methane gas. The preliminary study was set up to optimized the ratio of sewage
sludge (as inoculum) and decanter cake (as substrate) in batch biochemical
methane potential (BMP) in serum bottle of 125 mL volume for 30 days. The
effect of different inoculum to substrate ratios (I/S) on biogas production was
investigated at mesophilic condition (38 ± 1 °C) and constant initial pH 7. The
batch study was conducted at the ratio I/S of 2:1, ratio 1:1 and ratio 1:2 and
sewage sludge only as control experiment. The preliminary study resulted in
daily biogas collection for the ratio of 1:2 showed the highest cumulative biogas
production of 247 mL. Total solid content and ammonia removal had been
compared at initial and final fermentation in the biochemical methane potential
(BMP) batch fermentation. The highest methane yield was obtained at the mixing
ratio of 2:1 with 165.6 mL CH4/g VS and this ratio had been choose to be the
best I/S ratio from BMP test. Then the ratio of 2:1 is upscale into a lab-scale
anaerobic digester to determine the maximum production of methane gas. 6.4L
of anaerobic digester has been used with 5.6L of the working volume and was
fermented for 30 days. Cumulative biogas production resulted in 5848 mL and
cumulative methane gas production resulted in 10451 mL CH4/g VS.
Theoretically, biogas is mainly composed of methane (60 %) and carbon dioxide
(40 %) as of end product of anaerobic digestion. These were compared for all
ratios and resulted significantly as theoretical. The experimental value of
methane yield from lab-scale anaerobic digester then compared with the
theoretical value of methane yield by using the Gompertz equation solve in Excel
Solver. As a comparison, all co-digestion ratios produced more biogas than the
sewage sludge alone. This proved that anaerobic co-digestion of sewage sludge
and decanter cake can improve the production of biogas. |
|---|