Effects of Alkali Pre-treatment, Total Solid Content, Substrate to Inoculum Ratio, and pH on Biogas Production from Anaerobic Digestion of Mango Leaves

The pretreatment of organic solid waste plays a key role in achieving the highest degree of valorization within the anaerobic digestion processes. This work focuses on the use of ozone, discussing its effects, together with particle size and total solid content of waste, on the anaerobic biodegradability of the organic fraction of municipal solid waste (OFMWS). A Design of Experiment (DOE) strategy was used to identify statistically significant factors for further investigation. Experimental results showed that ozonation increased methane production, with the best results being obtained for samples characterized by the highest total solid content. The surplus methane generated by ozonated samples may also result in favourable net energy gain. These outcomes highlight the effectiveness of ozonation when applied in the pretreatment of OFMSW destined to anaerobic digestion and address the need for an energy balance to assess the competitiveness of this technology on an industrial scale.

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Anaerobic Co-digestion of Pineapple Wastes with Cow Dung: Effect of Different Total Solid Content on Bio-methane Yield

Advances in Agricultural and Food Research Journal ◽

10.36877/aafrj.a0000109 ◽

2020 ◽

Vol 1 (1) ◽

Author(s):

Adila Fazliyana Aili Hamzah ◽

Muhammad Hazwan Hamzah ◽

Fauzan Najmi Ahmad Mazlan ◽

Hasfalina Che Man ◽

Nur Syakina Jamali ◽

...

Keyword(s):

Biogas Production ◽

Renewable Energy Sources ◽

Total Solid ◽

Solid Content ◽

Methane Yield ◽

Cow Dung ◽

Total Solid Content ◽

Pineapple Waste ◽

Working Volume ◽

Substrate Ratio

The abundance of agricultural wastes produced from pineapple processing and livestock industries has resulted in the difficulties of disposing of a large amount of waste. Anaerobic digestion is a way to reduce waste and generate renewable energy sources including biogas. In this study, pineapple waste is co-digested with cow dung in batch experiments under mesophilic temperature at 38±1°C at a working volume of 100 ml in 125 ml serum bottle. The effects of the total solid on methane yields are investigated at a different substrate ratio. The batch study is conducted at 3 different total solid which are 12%, 20% and 28% and at three different substrate ratio cow dung to pineapple waste (CD: PW) (1:1, 1:2 and 1:3). Daily biogas collection for 28% total solid at 1:1 ratio results in the highest cumulative biogas production of 313 ml, followed by 28% total solid at 1:3 ratio with 246 ml biogas yield. The highest methane yield is achieved at 12% total solid with a 1:2 ratio (17.19 CH4/g VS). Results show that at 12% total solid produces the highest methane yield at all ratios compared to other total solid percentages. Moreover, methane yield decreases as the total solid percentage increases from 12% to 28%. Overall, the production of methane from pineapple wastes co-digested with cow dung is proven to be a good strategy to minimise solid wastes.

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Anaerobic digestion of food waste at varying operating conditions

Detritus ◽

10.31025/2611-4135/2020.14026 ◽

2020 ◽

pp. 99-105

Author(s):

Bipasyana Dhungana ◽

Sunil Prasad Lohani

Keyword(s):

Anaerobic Digestion ◽

Food Waste ◽

Continuous Process ◽

Batch Process ◽

Total Solid ◽

Gas Production ◽

Organic Substrate ◽

Solid Content ◽

Operating Conditions ◽

Total Solid Content

Food waste is one of the major problems contributing to the degradation of the environment, and thus needs serious attention. Among different options, anaerobic digestion is possibly the most effective technique for managing degradable waste, and produce renewable energy and fertilizer. Despite multiple-use and benefits of the technology, its application is limited due to a few technical challenges. This study focuses on the anaerobic digestion of food waste with the addition of different percentages of digested cow manure as inoculum to it, at different total solid content in ambient temperature. Anaerobic digestion of food waste in batch and semi-continuous processes were carried out in three different trials at an average temperature range of 20-26℃: Food waste with 20% inoculum, food waste with 50%, 100%, and 200% inoculum and 10% total solid content in batch process and food waste with 20% inoculum with 6% and 10% total solids content in the semi-continuous process. During each trial, some amount of gas production was observed, however, the gas composition showed a negligible amount of methane production (maximum 13% of CH4). There were two common problems detected in each trial: the inability to complete the methanogenesis process, and instability of the overall process due to the high degradability and acidic nature of food waste. Therefore, this study suggests that the mono digestion of food waste is not a suitable option. However, anaerobic co-digestion of food waste with different organic substrate might provide a favorable condition for stable anaerobic digestion as seen from preliminary results.

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APLIKASI PROSES DIGESTASI ANAEROBIK LUMPUR BIOLOGI INSTALASI PENGOLAHAN AIR LIMBAH INDUSTRI KERTAS

JURNAL SELULOSA ◽

10.25269/jsel.v4i02.64 ◽

2014 ◽

Vol 4 (02) ◽

Author(s):

Rina S. Soetopo ◽

Sri Purwati ◽

Henggar Hardiani ◽

Mukharomah Nur Aini ◽

Krisna Adhitya Wardhana

Keyword(s):

Oxygen Demand ◽

Total Solid ◽

Pilot Scale ◽

Organic Content ◽

Solid Content ◽

Uasb Reactor ◽

Anaerobic Sludge ◽

Organic Loading ◽

Total Solid Content ◽

Average Value

A continuous pilot scale study has been conducted to investigate the effectiveness of anaerobic digestion of biological sludge. The sludge has a total solid content of 0.53% - 1.1%, pH of 7.20 to 7.32. Its organic content is about 97 %, The research were conducted in two stages, which are acidification (performed in 3 m3 the Continously Stirred Tank Reactor/CSTR at pH of 5.5 to 6.0) and methanation (performed in 5 m3 the Up Flow Anaerobic Sludge Blanket/UASB reactor at pH 6.5 to 7.0). The retention time (RT) was gradually shortened from 6 days to 1 day for acidification and from 8 days to 2 days for methanation. The results showed that operating the CSTR at the RT of 1 day and the organic loading of 8.23 g Volatile Solid (VS)/m3.day could produce Volatile Fatty Acid (VFA) at an average value of 17.3 g/kg VS.day. Operating the UASB reactor at the RT of 2 days and the organic loading (Chemical Oxygen Demand/COD) of 2.4 kg COD/m3.day could produce biogas at an average value of 66.3 L/day, with an average methane content of 69.9%, methane rate of 0.17 L CH4/g COD reduction or 19.06 L CH4/kg VS. Furthermore, methanation could reduce COD at an average value of 51.2 %, resulting in the effluent average value of COD filtrate and COD total of 210.1 mg/L and 375.2 mg /L, respectively.Keywords: acidification, methanation, CSTR, UASB, biogas ABSTRAKPercobaan digestasi anaerobik lumpur IPAL biologi industri kertas secara kontinyu skala pilot telah dilakukan di industri kertas dengan tujuan mengkaji efektivitas proses digestasi anaerobik dalam mengolah lumpur tersebut. Lumpur yang digunakan memiliki total solids sekitar 0,53% – 1,1%, pH netral (7,20 – 7,32) dengan komponen utama senyawa organik sekitar 97%. Percobaan dilakukan dalam dua tahap yaitu asidifikasi dalam reaktor CSTR berkapasitas 3 m3 pada pH 5,5 – 6,0 dan metanasi dalam reaktor UASB berkapasitas 5 m3 pada pH 6,5 – 7,0. Percobaan dilakukan dengan waktu retensi yang dipersingkat secara bertahap dari 6 hari ke 1 hari untuk proses asidifikasi dan dari 8 hari ke 2 hari untuk proses metanasi. Hasil percobaan menunjukkan bahwa pengoperasian reaktor CSTR dengan waktu retensi 1 hari dan beban organik 8,3 g VS/m3.hari dapat menghasilkan VFA rata-rata 17,3 g/kg VS.hari dengan kisaran 8,36 – 30,59 g/kg VS.hari, sedangkan pengoperasian reaktor UASB pada waktu retensi 2 hari dan beban organik 2,4 kg COD/m3.hari dapat menghasilkan biogas rata-rata 66,3 L/hari dengan kadar metana rata-rata 69,9% atau 0,17 L CH4/g COD reduksi atau 19,06 L CH4/kg VS. Selain itu proses metanasi dapat menurunkan COD terlarut rata-rata 51,2%, dengan konsentrasi efluen COD terlarut rata-rata 210,1 mg/L dan COD total rata-rata 375,2 mg/L.Kata kunci: asidifikasi, metanasi, CSTR, UASB, biogas

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A simple design and operation for the anaerobic treatment of highly concentrated swine waste in the tropics

Water Science & Technology ◽

10.2166/wst.1995.0466 ◽

1995 ◽

Vol 32 (12) ◽

pp. 91-97 ◽

Cited By ~ 1

Author(s):

P. Y. Yang ◽

M. Kuroshima

Keyword(s):

Treatment Process ◽

Total Solid ◽

Anaerobic Treatment ◽

Solid Content ◽

Total Solid Content ◽

Treatment Processes ◽

Tropical Conditions ◽

Biological Reaction ◽

The Tropics ◽

Small Producers

In order to develop a simple operation for an anaerobic treatment process for highly concentrated pig wastewater for small producers, a three-stage anaerobic treatment process was investigated. The system provided a series of mixing, homogenization, biological reaction and final stabilization of concentrated pig waste (total solid content of 8–10%). The process provided a stable operational performance, simple operational procedure and well stabilized sludge effluent. It was also found that the system is economically feasible in Hawaii. Compared to the other treatment processes for highly concentrated pig waste, this process is considered as an appropriate alternative for the application of the small producers in land limited and tropical conditions. Also, the present treatment system can be easily developed into a prefabricated package plant which can minimize the on-site labor and building costs.

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Alkali pre-treatment of Sorghum Moench for biogas production

Chemical Papers ◽

10.2478/s11696-012-0298-0 ◽

2013 ◽

Vol 67 (9) ◽

Cited By ~ 12

Author(s):

Karina Michalska ◽

Stanisław Ledakowicz

Keyword(s):

Anaerobic Digestion ◽

Chemical Oxygen Demand ◽

Volatile Fatty Acids ◽

Biogas Production ◽

Oxygen Demand ◽

Total Phenolic ◽

Methane Generation ◽

Pre Treatment ◽

Alkali Hydrolysis ◽

Almost All

AbstractThis work studies the influence of the alkali pre-treatment of Sorghum Moench — a representative of energy crops used in biogas production. Solutions containing various concentrations of sodium hydroxide were used to achieve the highest degradation of lignocellulosic structures. The results obtained after chemical pre-treatment indicate that the use of NaOH leads to the removal of almost all lignin (over 99 % in the case of 5 mass % NaOH) from the biomass, which is a prerequisite for efficient anaerobic digestion. Several parameters, such as chemical oxygen demand, total organic carbon, total phenolic content, volatile fatty acids, and general nitrogen were determined in the hydrolysates thus obtained in order to define the most favourable conditions. The best results were obtained for the Sorghum treated with 5 mass % NaOH at 121°C for 30 min The hydrolysate thus achieved consisted of high total phenolic compounds concentration (ca. 4.7 g L−1) and chemical oxygen demand value (ca. 45 g L−1). Although single alkali hydrolysis causes total degradation of glucose, a combined chemical and enzymatic pre-treatment of Sorghum leads to the release of large amounts of this monosaccharide into the supernatant. This indicates that alkali pre-treatment does not lead to complete cellulose destruction. The high degradation of lignin structure in the first step of the pre-treatment rendered the remainder of the biomass available for enzymatic action. A comparison of the efficiency of biogas production from untreated Sorghum and Sorghum treated with the use of NaOH and enzymes shows that chemical hydrolysis improves the anaerobic digestion effectiveness and the combined pre-treatment could have great potential for methane generation.

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