Mechanical pretreatment of municipal biowaste to produce an aqueous slurry dedicated to anaerobic digestion

This research investigates the effect of sludge pretreatment on the anaerobic digestion of waste-activated sludge (WAS). In the key of this sludge pretreatment process, bacteria in the WAS were ruptured by mechanical jet and smashed under pressurized conditions. The protein concentrations in the sludge varied significantly after pretreatment. Protein concentration increased according to jet times and pressure. In batch experiments, volatile solids (VS) removal efficiencies were 13∼50% when the WAS pretreated once under 30 bar was fed into an anaerobic digester with 2∼26 day retention time. In the same operating conditions, when intact WAS was fed into the digester, VS removal efficiencies were 2∼35%. Therefore, it is recognized that higher digestion efficiencies of the WAS were obtained through a mechanical pretreatment of sludge.

Download Full-text

Mechanical pretreatment of waste activated sludge for anaerobic digestion process

Water Research ◽

10.1016/s0043-1354(99)00361-9 ◽

2000 ◽

Vol 34 (8) ◽

pp. 2362-2368 ◽

Cited By ~ 126

Author(s):

I Nah

Keyword(s):

Anaerobic Digestion ◽

Activated Sludge ◽

Waste Activated Sludge ◽

Anaerobic Digestion Process ◽

Digestion Process ◽

Mechanical Pretreatment

Download Full-text

Enhancement of biogas production from rice husk using mechanical pretreatment (grinding) in Liquid Anaerobic Digestion (L-AD)

E3S Web of Conferences ◽

10.1051/e3sconf/202020208003 ◽

2020 ◽

Vol 202 ◽

pp. 08003

Author(s):

Syafrudin ◽

Winardi Dwi Nugraha ◽

Soraya Annisa Putri ◽

Hashfi Hawali Abdul Matin ◽

Budiyono

Keyword(s):

Anaerobic Digestion ◽

Rice Husk ◽

Biogas Production ◽

Physical Treatment ◽

Mechanical Pretreatment ◽

Preparation Stage ◽

Pre Treatment ◽

Operation Phase ◽

Gas Volume ◽

Biogas Technology

Biogas technology is an alternative solution to the energy crisis issue in Indonesia. This study focuses on determining the optimum value of grind size variations in biogas production using the Liquid Anaerobic Digestion (L-AD) from rice husk waste. It is consists of the preparation stage, total solids calculation, the operation phase, and results analysis. The rice husk is collected from Rowosari village, and it has been pre-treated by 6% NaOH of chemical pre-treatment. The physical treatment uses numerous grind sizes, including un-grinded rice husk as control, and the 10 mesh, 18 mesh, 35 mesh, 60 mesh of rice husk as an observed variable. All variables are duplicate into 12 reactors, and the biogas production is observed by collecting gas volume in each reactor for 60 days. The calculated biogas is expressed by ml/grTS. The result shows that the grind size of 10 mesh, 18 mesh, 35 mesh, and 60 mesh rice husk produces a total biogas rate of 54.95, 44.86, 58.13, and 72.14 ml/grTS respectively. The rice husk control produces 9.67 ml/gr TS as the lowest rate of biogas production compared to the others, while the 60 mesh rice husk becomes the highest biogas production rate.

Download Full-text

Characterization of municipal biowaste categories for their capacity to be converted into a feedstock aqueous slurry to produce methane by anaerobic digestion

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.137084 ◽

2020 ◽

Vol 716 ◽

pp. 137084 ◽

Cited By ~ 3

Author(s):

P. Moretti ◽

J. Morais de Araujo ◽

A. Borges de Castilhos ◽

P. Buffière ◽

R. Gourdon ◽

...

Keyword(s):

Anaerobic Digestion ◽

Aqueous Slurry

Download Full-text

The effect of mechanical pretreatment on the anaerobic digestion of Hybrid Pennisetum

Fuel ◽

10.1016/j.fuel.2019.04.134 ◽

2019 ◽

Vol 252 ◽

pp. 469-474 ◽

Cited By ~ 12

Author(s):

Xihui Kang ◽

Yi Zhang ◽

Bing Song ◽

Yongming Sun ◽

Lianhua Li ◽

...

Keyword(s):

Anaerobic Digestion ◽

Mechanical Pretreatment ◽

Hybrid Pennisetum

Download Full-text

A mechanical pretreatment of waste activated sludge for improvement of anaerobic digestion system

Water Science & Technology ◽

10.2166/wst.1997.0437 ◽

1997 ◽

Vol 36 (12) ◽

pp. 111-116 ◽

Cited By ~ 5

Author(s):

Kyung-Yub Hwang ◽

Eung-Bai Shin ◽

Hong-Bok Choi

Keyword(s):

Anaerobic Digestion ◽

Activated Sludge ◽

Protein Concentration ◽

Waste Activated Sludge ◽

Cell Rupture ◽

Mechanical Pretreatment ◽

Solids Concentration ◽

Sludge Pretreatment ◽

Volatile Solids ◽

Before And After

This study evaluated the effectiveness of sewage pretreatment as it affected the subsequent anaerobic digestion of waste activated sludge (WAS). The key to this sludge pretreatment process was that microorganism cells within WAS were ruptured by mechanical jet and smash under pressurized conditions, 5–50 bar pressure. Cell rupture was estimated by soluble protein concentration (SPC) because the cytoplasm of microorganisms is mainly composed of protein. The SPC in the WAS varied significantly before and after pretreatment. In particular, cell rupture increased from 6% to 43% with the increase of the pretreated pressure (5–30bar), volatile solids concentration and thickening time of WAS. In the WAS pretreatment with long-thickening time (12h < thickening time ≤ 48h), cell rupture was monitored 5–10 % higher than short-thickening time (Oh <thickening time ≤ 12h). Generally, it was observed that higher anaerobic digestion efficiencies of WAS could be obtained according to the increase of microorganism cell rupture through mechanical pretreatment of WAS.

Download Full-text

Effects of Sludge Concentration and Disintegration/Solubilization Pretreatment Methods on Increasing Anaerobic Biodegradation Efficiency and Biogas Production

Sustainability ◽

10.3390/su132212887 ◽

2021 ◽

Vol 13 (22) ◽

pp. 12887

Author(s):

Jeong-Yoon Ahn ◽

Soon-Woong Chang

Keyword(s):

Heat Treatment ◽

Anaerobic Digestion ◽

Biogas Production ◽

Anaerobic Biodegradation ◽

Sludge Sample ◽

Sludge Treatment ◽

Mechanical Pretreatment ◽

Sludge Pretreatment ◽

Before And After ◽

Negative Impacts

It is urgent to determine suitable municipal sludge treatment solutions to simultaneously minimize the environmental negative impacts and achieve sustainable energy benefits. In this study, different sludge pretreatment techniques were applied and investigated to enhance the sludge solubility and, subsequently, facilitate the anaerobic biodegradation performance of the mixed sludge under different sludge concentrations and pretreatment techniques. The sludge characteristics before and after pretreatment and batch experiments of anaerobic digestion of sludge samples under different conditions were analyzed and discussed. The results showed that the mechanical pretreatment method, alone and in combination with low-temperature heat treatment, significantly improved the sludge solubility, with the highest solubility at 39.23%. The maximum biomethane yield achieved was 0.43 m3/kg after 10 d of anaerobic digestion of a 3% sludge sample subjected to mechanical and thermal pretreatment prior to anaerobic biodegradation. In comparison, it took more than 28 d to achieve the same biomethane production with the unpretreated sludge sample. Mechanical pretreatment and subsequent heat treatment showed a high ability to dissolve sludge and, subsequently, accelerate anaerobic digestion, thereby providing promising prospects for increasing the treatment capacity of existing and new sludge treatment plants.

Download Full-text