Enhanced high-quality biomethane production from anaerobic digestion of primary sludge by corn stover biochar

This research applied sodium hydroxide (NaOH) pretreatment and trace elements to improve biomethane production when using corn stover for anaerobic digestion. Full-factor experimental tests identified the best combination of trace elements with the NaOH pretreatment, indicating that the best combination was with 1.0, 0.4, and 0.4 mg·L−1·d−1of elements Fe, Co, and Ni, respectively. The cumulative biomethane production adding NaOH pretreatment and trace elements was 11,367 mL; total solid bioconversion rate was 55.7%, which was 41.8%–62.2% higher than with NaOH-pretreatment alone and 22.2%–56.3% higher than with untreated corn stover. The best combination was obtained 5–9 days shorter than T90and maintained good system operation stability. Only a fraction of the trace elements in the best combination was present in the resulting solution; more than 85% of the total amounts added were transferred into the solid fraction. Adding 0.897 g of Fe, 0.389 g of Co, and 0.349 g of Ni satisfied anaerobic digestion needs and enhanced biological activity at the beginning of the operation. The results showed that NaOH pretreatment and adding trace elements improve corn stover biodegradability and enhance biomethane production.

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Comparison of Initial pH Adjustment Prior to Thermophilic Anaerobic Digestion of Lime-Treated Corn Stover via Liquid Digestate or CO2

Applied Sciences ◽

10.3390/app112210884 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10884

Author(s):

Lei Xiao ◽

Man Yang ◽

Di Hu ◽

Yuxia Mei ◽

Shumiao Zhao ◽

...

Keyword(s):

Anaerobic Digestion ◽

Solid State ◽

Corn Stover ◽

Thermophilic Anaerobic Digestion ◽

Economic Method ◽

Liquid Digestate ◽

Net Profit ◽

Reagent Cost ◽

Initial Ph ◽

Biomethane Production

Neutralization with liquid digestate and CO2 was compared herein to adjust the pH of lime-treated corn stover. The effects on the thermophilic (55 °C) anaerobic digestion were also analyzed. Liquid digestate neutralization (LDN) caused a decrease in pH from 10.5 to 7.5 in 60 h and accumulation of acetic/isobutyric acids. The CO2 neutralization (CN) under solid-state conditions reduced the pH from 10.5 to 8.5 in 30 min, which is faster than that of LDN and did not affect the subsequent anaerobic digestion. Biomethane production rate indicates that LDN contributed to the performance of anaerobic digestion, but this was not sufficient to compensate for the loss of total biomethane yield, resulting in a negative net profit (i.e., revenue from increased energy production minus reagent cost). For CN under solid-state conditions, the biomethane production was highest in both liquid- and solid-state anaerobic digestion, and also obtained a net profit of 98.74–100.89 RMB/tonne dry biomass. Therefore, the solid-state condition CN is a more efficient and economic method for adjusting initial pH of lime-treated corn stover.

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Lignocellulosic Corn Stover Biomass Pre-Treatment by Deep Eutectic Solvents (DES) for Biomethane Production Process by Bioresource Anaerobic Digestion

Sustainability ◽

10.3390/su131910504 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10504

Author(s):

Akinola David Olugbemide ◽

Ana Oberlintner ◽

Uroš Novak ◽

Blaž Likozar

Keyword(s):

Anaerobic Digestion ◽

Corn Stover ◽

Deep Eutectic Solvent ◽

Ammonium Thiocyanate ◽

Deep Eutectic Solvents ◽

Waste Biomass ◽

Liquid Ratio ◽

Biomethane Production ◽

Pre Treatment ◽

Pretreated Biomass

The valorization study of the largely available corn stover waste biomass after pretreatment with deep eutectic solvent (DES) for biomethane production in one-liter glass bioreactors by anaerobic digestion for 21 days was presented. Ammonium thiocyanate and urea deep eutectic solvent pretreatments under different conditions in terms of the components ratio and temperature were examined on corn stover waste biomass. The lignocellulose biomass was characterized in detail for its chemistry and morphology to determine the effect of the pretreatment on the natural biocomposite. Furthermore, the implications on biomethane production through anaerobic digestion with different loadings of corn stover biomass at 35 g/L and 50 g/L were tested. The results showed an increase of 48% for a cumulative biomethane production for a DES-pretreated biomass, using a solid-to-liquid ratio of 1:2 at 100 °C for 60 min, which is a strong indication that DES-pretreatment significantly enhanced biomethane production.

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Potential of Grass for Biomethane Production in Anaerobic Digestion using Bioprocess Control AMPTS II

7th International Conference on Latest Trends in Engineering and Technology (ICLTET'2015) Nov. 26-27, 2015 Irene, Pretoria (South Africa) ◽

10.15242/iie.e1115037 ◽

2015 ◽

Keyword(s):

Anaerobic Digestion ◽

Bioprocess Control ◽

Biomethane Production

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Anaerobic Digestion of Primary Sludge Containing Iron Phosphate

Water Quality Research Journal ◽

10.2166/wqrj.1973.008 ◽

1973 ◽

Vol 8 (1) ◽

pp. 91-109 ◽

Cited By ~ 2

Author(s):

M.E. Jack ◽

G.J. Farquhar ◽

G.M. Cornwall

Keyword(s):

Anaerobic Digestion ◽

Phosphorus Removal ◽

Municipal Wastewater ◽

Iron Phosphate ◽

Chemical Precipitation ◽

Task Group ◽

Iron Compounds ◽

Primary Sludge ◽

Group Report ◽

Aluminum Compounds

Abstract The importance of phosphorus as a nutrient in the eutrophication of lakes and rivers has been well established (Fruh 1967). It has been shown in addition that a significant amount of this phosphorus arises from the discharge of treated and untreated municipal wastewater (Task Group Report 1967). Consequently, measures are being taken, notably in the Province of Ontario, for removal of phosphorus from wastewater by means of chemical precipitation. Chemicals exhibiting satisfactory phosphorus removal include lime, iron compounds and aluminum compounds (Leckie and Stumm 1970; Schmid 1968; Wuhrman 1968).

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