scholarly journals Synergistic Co-Digestion of Microalgae and Primary Sludge to Enhance Methane Yield from Temperature-Phased Anaerobic Digestion

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4547
Author(s):  
Mekdimu Mezemir Damtie ◽  
Jingyeong Shin ◽  
Hyun Min Jang ◽  
Young Mo Kim
Keyword(s):  
Anaerobic Digestion ◽  
Synergistic Effects ◽  
Operating Conditions ◽  
Methane Yield ◽  
Biological Pretreatment ◽  
Primary Sludge ◽  
Thermophilic Conditions ◽  
Methane Potential ◽  
Pretreatment Conditions ◽  
Anaerobic Pretreatment

A two-stage temperature-phased mesophilic anaerobic digestion assay was carried out to study the interaction between various biological pretreatment conditions and the possible synergistic co-digestion of microalgae and primary sludge. The study of growth kinetics of the biochemical methane potential test revealed that a maximum of 36% increase in methane yield was observed from co-digestion of a substrate pretreated by thermophilic aerobic conditions (55 °C and HRT = 2 days) and an 8.3% increase was obtained from the anaerobic pretreated substrate (55 °C and HRT = 3 days). Moreover, no synergistic effects on methane yields were observed in co-digesting the substrate pretreated with high temperature (85 °C). The study also identified specific conditions in which interaction between biological pretreatment and co-digestion might substantially reduce methane yield. Careful optimization of operating conditions, both aerobic and anaerobic pretreatment at moderate thermophilic conditions, can be used as a biological pretreatment to enhance methane yield from the co-digestion of microalgae and primary sludge.

scholarly journals A Novel Nitrogen Removal Technology Pre-Treating Chicken Manure, Prior to Anaerobic Digestion

2020 ◽  
Vol 12 (18) ◽  
pp. 7463
Author(s):  
Marie E. Kirby ◽  
Muhammad W. Mirza ◽  
James Davies ◽  
Shane Ward ◽  
Michael K. Theodorou
Keyword(s):  
Anaerobic Digestion ◽  
Nitrogen Removal ◽  
Recovery Process ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Chicken Manure ◽  
Nitrogen Recovery ◽  
Biochemical Methane Potential ◽  
Removal Technology ◽  
Methane Potential

Chicken manure is an agricultural by-product that is a problematic feedstock for anaerobic digestion due to its high nitrogen content inhibiting methane yields. This research examines a novel pilot-scale method of ammonia stripping, the nitrogen recovery process (NRP) developed by Alchemy Utilities Ltd. The NRP was designed to remove and recover nitrogen from chicken manure and two different operating conditions were examined. Both operating conditions demonstrated successful nitrogen removal and recovery. The biochemical methane potential assays were used to compare the digestibility of the NRP-treated chicken manures to that of a fresh chicken manure control. Overall, the biochemical methane potential assays demonstrated that some NRP-treated chicken manure treatments produced significantly more methane compared to untreated manure, with no inhibition occurring in relation to ammonium. However, some of the NRP-treated chicken manures produced similar or lower methane yields compared to fresh chicken manure. The NRP requires further development to improve the efficiency of the pilot-scale unit for commercial-scale operation and longer-term continuous anaerobic digestion trials are required to determine longer-term methane yield and ammonium inhibition effects. However, these initial results clearly demonstrate the technology’s potential and novel application for decentralised, on-farm nitrogen recovery and subsequent anaerobic digestion of chicken manure.

Effects of Co-Substrates and Mixing Ratio on the Anaerobic Digestion of Navel Orange Waste

2014 ◽  
Vol 878 ◽  
pp. 473-480 ◽  
Author(s):  
Jin Rong Qiu ◽  
Yun Long Fu ◽  
Qing Yun Liu ◽  
Shun Yi Li ◽  
Hai Jun Peng ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Synergistic Effects ◽  
Swine Manure ◽  
Methane Yield ◽  
Navel Orange ◽  
Mixing Ratio ◽  
High Concentration ◽  
Active Sludge ◽  
Promising Alternative ◽  
Orange Waste

The Gannan region is the largest navel orange planting area in the world and has the largest production in China. However, about 5 million tons of navel orange waste (NOW) produced annually. NOW has a great environmental risk because of its high content of organic matter and moisture. Anaerobic digestion of NOW with high nitrogen content waste is a promising alternative to treat these wastes. The effect of swine manure (SM), waste active sludge (WAS) as co-substrates and different mixing ratio were examined in three batch-scale studies. In the first investigation, co-digestion of NOW with SM resulted low methane yield and high concentration of VFAs. In the second investigation, NOW was co-digested with WAS, the methane yield was improved by 260% when the mixing ratio of NOW to WAS (VS/VS) was shifted from 1:2 to 2:1. In the third investigation, the co-digestion of NOW with SM and WAS was conducted. Co-digestion of three substrates has higher methane yield than that of previous two studies, with the exception of equal amounts of NOW with co-substrates (mixing ratio of NOW to SM to WAS was 2:1:1). The highest methane yield of all experiments was 0.20 m3 kg-1VS added while the mixing ratio of NOW to SM to WAS was 1:2:1. It seemed to obtain stable digestion performance, the mixing ratio of co-substates to NOW should not be lower than 1:1. WAS was a better co-substrate than SM, as WAS was capable to supply more organic nitrogen to create positive synergistic effects.

Anaerobic digestion of sunflower oil cake: a current overview

2013 ◽  
Vol 67 (2) ◽  
pp. 410-417 ◽  
Author(s):  
M. A. De la Rubia ◽  
V. Fernández-Cegrí ◽  
F. Raposo ◽  
R. Borja
Keyword(s):  
Anaerobic Digestion ◽  
Sunflower Oil ◽  
Physical Structure ◽  
Methane Yield ◽  
Organic Loading Rate ◽  
Biochemical Methane Potential ◽  
In Series ◽  
Methane Potential ◽  
Bmp Test ◽  
Sunflower Oil Cake

Due to the chemical and physical structure of a lignocellulosic biomass, its anaerobic digestion (AD) is a slow and difficult process. In this paper, the results obtained from a batch biochemical methane potential (BMP) test and fed-batch mesophilic AD assays of sunflower oil cake (SuOC) are presented. Taking into account the low digestibility shown during one-stage experiments the methane yield decreased considerably after increasing the organic loading rate (OLR) from 2 to 3 g VS L−1 d−1, SuOC was subjected to a two-stage AD process (hydrolytic-acidogenic and methanogenic stages), in two separate reactors operating in series where the methanogenic stage became acidified (with >1,600 mg acetic acid L−1) at an OLR as low as 2 g VS L−1 d−1. More recently, BMP assays were carried out after mechanical, thermal, and ultrasonic pre-treatments to determine the best option on the basis of the methane yield obtained.

scholarly journals Influence of the Preliminary Storage on Methane Yield of Anaerobic Digestion of the Organic Fraction of Municipal Solid Waste

Processes ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 2017
Author(s):  
Domenica Pangallo ◽  
Altea Pedullà ◽  
Demetrio Antonio Zema ◽  
Paolo S. Calabrò
Keyword(s):  
Anaerobic Digestion ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Storage Time ◽  
Logistic Models ◽  
Methane Yield ◽  
Organic Fraction ◽  
Biochemical Methane Potential ◽  
First Order ◽  
Methane Potential

Anaerobic digestion (AD) is a suitable management option for the energy valorization of many wastes, including the organic fraction of municipal solid waste (OFMSW). However, in some cases, long storage after the separate collection of this waste is required for management reasons, especially when the amount of waste to be treated temporarily exceeds the capacity of available AD plants. This study evaluates the biochemical methane potential (BMP) of the OFMSW after preliminary storage of 2, 6, and 10 days, in order to assess whether they are still suitable for AD or not. Moreover, the accuracy of three kinetic models (first order, Gompertz, and logistic models) in estimating the methane yield of stored OFMSW is tested. The resulting methane yield was between about 500 and 650 NmL·gVS−1 and slightly increased with the increase of the storage time after collection. Overall, this study has demonstrated that storage of OFMSW, when the collected amount of solid waste exceeds the treatment capacity of AD plants, a storage time up to 10 days does not impact the methane yield of the process.

scholarly journals Effect of Pasteurisation on Methane Yield from Food Waste and Other Substrates in Anaerobic Digestion

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1351
Author(s):  
Yue Zhang ◽  
Sigrid Kusch-Brandt ◽  
Sonia Heaven ◽  
Charles J. Banks
Keyword(s):  
Anaerobic Digestion ◽  
Food Waste ◽  
Statistical Significance ◽  
Methane Yield ◽  
Volatile Components ◽  
Cattle Slurry ◽  
Animal Blood ◽  
Potato Waste ◽  
Methane Potential ◽  
The Difference

The effect of pasteurisation and co-pasteurisation on biochemical methane potential values in anaerobic digestion (AD) was studied. Pasteurisation prior to digestion in a biogas plant is a common hygienisation method for organic materials which contain or have been in contact with animal by-products. Tests were carried out on food waste, slaughterhouse waste, animal blood, cattle slurry, potato waste, card packaging and the organic fraction of municipal solid waste (OFMSW); pasteurisation at 70 °C for 1 h was applied. Pasteurisation had increased the methane yields of blood (+15%) and potato waste (+12%) only, which both had a low content of structural carbohydrates (hemi-cellulose and cellulose) but a particularly high content of either non-structural carbohydrates such as starch (potato waste) or proteins (blood). With food waste, card packaging and cattle slurry, pasteurisation had no observable impact on the methane yield. Slaughterhouse waste and OFMSW yielded less methane after pasteurisation in the experiments (but statistical significance of the difference between pasteurised and unpasteurised slaughterhouse waste or OFMSW was not confirmed in this work). It is concluded that pasteurisation can positively impact the methane yield of some specific substrates, such as potato waste, where heat-treatment may induce gelatinisation with release of the starch molecules. For most substrates, however, pasteurisation at 70 °C is unlikely to increase the methane yield. It is unlikely to improve biodegradability of lignified materials, and it may reduce the methane yield from substrates which contain high contents of volatile components. Furthermore, in this experimental study, the obtained methane yield was unaffected by whether the substrates were pasteurised individually and then co-digested or co-pasteurised as a mixture before batch digestion.

scholarly journals Synergistic Effects of Magnetic Nanomaterials on Post-Digestate for Biogas Production

Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6434
Author(s):  
Emmanuel Kweinor Tetteh ◽  
Gloria Amo-Duodu ◽  
Sudesh Rathilal
Keyword(s):  
Energy Savings ◽  
Biogas Production ◽  
Synergistic Effects ◽  
Magnetic Nanomaterials ◽  
Methane Yield ◽  
High Water Content ◽  
Wastewater Management ◽  
Water And Wastewater Treatment ◽  
Working Volume ◽  
Methane Potential

Digestate is characterized by high water content, and in the water and wastewater treatment settings, necessitates both large storage capacities and a high cost of disposal. By seeding digestate with four magnetic nanoparticles (MNPs), this study aimed to recover biogas and boost its methane potential anaerobically. This was carried out via biochemical methane potential (BMP) tests with five 1 L bioreactors, with a working volume of 80% and 20% head space. These were operated under anaerobic conditions at a temperature 40 °C for a 30 d incubation period. The SEM/EDX results revealed that the morphological surface area of the digestate with the MNPs increased as compared to its raw state. Comparatively, the degree of degradation of the bioreactors with MNPs resulted in over 75% decontamination (COD, color, and turbidity) as compared to the control system result of 60% without MNPs. The highest biogas production (400 mL/day) and methane yield (100% CH4) was attained with 2 g of Fe2O4-TiO2 MNPs as compared to the control biogas production (350 mL/day) and methane yield (65% CH4). Economically, the highest energy balance achieved was estimated as 320.49 ZAR/kWh, or 22.89 USD/kWh in annual energy savings for this same system. These findings demonstrate that digestate seeded with MNPs has great potential to improve decontamination efficiency, biogas production and circular economy in wastewater management.

scholarly journals Mesophilic Anaerobic Digestion of Hydrothermally Pretreated Lignocellulosic Biomass (Norway Spruce (Picea abies))

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 190
Author(s):  
Nirmal Ghimire ◽  
Rune Bakke ◽  
Wenche Hennie Bergland
Keyword(s):  
Anaerobic Digestion ◽  
Picea Abies ◽  
Norway Spruce ◽  
Oxygen Demand ◽  
Hot Water ◽  
Methane Yield ◽  
Negative Effect ◽  
Pretreatment Conditions ◽  
Soluble Lignin ◽  
Different Levels

Hot water extraction (HWE) removes hemicellulose from woody biomass to give improved end products while producing a sugar-rich by-product stream, which requires proper treatment before disposal. Hot water extracted Norway spruce (Picea abies) at two different pretreatment conditions (140 °C for 300 min (H140) and 170 °C for 90 min (H170)) generated hydrolysate as a by-product, which was used in mesophilic anaerobic digestion (AD) as substrate. H140 gave a higher methane yield (210 NmL/g COD—chemical oxygen demand) than H170 (148 NmL/g COD) despite having a lower concentration of sugars, suggesting that different levels of inhibitors (furans and soluble lignin) and recalcitrant compounds (soluble lignin) affected the methane yield significantly. Organic loads (OLs) had a negative effect on the methane yield, as observed during AD of H170, while such an effect was not observed in the case of H140. This suggests that the decrease in methane yield (32%) of H170 compared to H140 is primarily due to inhibitors, while the decrease in methane yield (19%) of H140 compared to the synthetic hydrolysate is primarily due to recalcitrant substances. Therefore, both OL and pretreatment conditions must be considered for efficient anaerobic digestion from hydrolysate for enhanced methane production.

scholarly journals Bioenergy Production through Mono and Co-Digestion of Tomato Residues

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5563
Author(s):  
Patrícia V. Almeida ◽  
Rafaela P. Rodrigues ◽  
Leonor M. Teixeira ◽  
Andreia F. Santos ◽  
Rui C. Martins ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Operating Conditions ◽  
Fractional Factorial ◽  
Optimum Operating ◽  
Solids Concentration ◽  
Volatile Solids ◽  
Working Volume ◽  
Substrate To Inoculum Ratio ◽  
Methane Potential ◽  
High Concentrations

The agro-industry of tomato generates three types of residues: ripe rotten tomato (unfit for consumption) (RT), green (unripe) tomato (GT), and tomato branches including leaves and stems (TB). These materials are commonly wasted or used as feed for livestock. Energy production through anaerobic digestion is an alternative way to manage and simultaneously valorise these materials. Initially, the operating conditions of mono anaerobic digestion were investigated using RT. Thus, a design of experiments based on a two-level fractional factorial design with resolution V was performed to determine the factors that affect biochemical methane potential (BMP). The substrate to inoculum ratio (SIR), total volatile solids concentration (VSt), working volume (WV), presence of nutrients (Nu), and the pre-incubation of the inoculum (Inc) were investigated. The results showed that SIR is the most important factor. The maximum BMP for RT was 297 NmLCH4/gVS with SIR = 0.5; tVS = 20 g/L; WV = 20%; no pre-incubation and the presence of nutrients. Using these optimum operating conditions, co-digestion was investigated through a mixture design approach. The substrates RT and GT presented similar BMP values, whereas TB led to a significantly lower BMP. Indeed, when high concentrations of TB were used, a significant decrease in methane production was observed. Nonetheless, the highest BMP was achieved with a mixture of 63% RT + 20% GT + 17% TB, with a production of 324 NmLCH4/gVS, corresponding to a synergetic co-digestion performance index of about 1.20. In general, although the substrate RT generates the highest BMP, the mixture with GT did not impair the methane yield. Overall, the co-digestion of tomato residues must be conducted with SIR close to 0.5 and the content of tomato branches in the reaction mixture should be kept low (up to 20%).

scholarly journals Simultaneous Synergy in CH4 Yield and Kinetics: Criteria for Selecting the Best Mixtures during Co-Digestion of Wastewater and Manure from a Bovine Slaughterhouse

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 384
Author(s):  
Zamir Sánchez ◽  
Davide Poggio ◽  
Liliana Castro ◽  
Humberto Escalante
Keyword(s):  
Anaerobic Digestion ◽  
Binary Mixtures ◽  
Synergistic Effects ◽  
Physicochemical Characteristics ◽  
High Potential ◽  
Multicomponent Mixtures ◽  
Biochemical Methane Potential ◽  
Slaughterhouse Wastewater ◽  
Methane Potential ◽  
Better Than

Usually, slaughterhouse wastewater has been considered as a single substrate whose anaerobic digestion can lead to inhibition problems and low biodegradability. However, the bovine slaughter process generates different wastewater streams with particular physicochemical characteristics: slaughter wastewater (SWW), offal wastewater (OWW) and paunch wastewater (PWW). Therefore, this research aims to assess the anaerobic co-digestion (AcoD) of SWW, OWW, PWW and bovine manure (BM) through biochemical methane potential tests in order to reduce inhibition risk and increase biodegradability. A model-based methodology was developed to assess the synergistic effects considering CH4 yield and kinetics simultaneously. The AcoD of PWW and BM with OWW and SWW enhanced the extent of degradation (0.64–0.77) above both PWW (0.34) and BM (0.46) mono-digestion. SWW Mono-digestion showed inhibition risk by NH3, which was reduced by AcoD with PWW and OWW. The combination of low CH4 potential streams (PWW and BM) with high potential streams (OWW and SWW) presented stronger synergistic effects than BM-PWW and SWW-OWW mixtures. Likewise, the multicomponent mixtures performed overall better than binary mixtures. Furthermore, the methodology developed allowed to select the best mixtures, which also demonstrated energy and economic advantages compared to mono-digestions.

Использование аппарата вихревого слоя для повышения эффективности метанового сбраживания осадков сточных вод

2019 ◽  
pp. 32-40 ◽  
Author(s):  
Y. Litti ◽  
D. Kovalev ◽  
A. Kovalev ◽  
I. Katraeva ◽  
E. Mikheeva ◽  
...  
Keyword(s):  
Organic Matter ◽  
Anaerobic Digestion ◽  
Kinetic Parameters ◽  
Wastewater Sludge ◽  
Methane Yield ◽  
Technological Parameters ◽  
Vortex Layer ◽  
Before And After ◽  
Thermophilic Conditions ◽  
Mineralization Of Organic Matter

Повышение эффективности анаэробного сбраживания осадков сточных вод, включая увеличение выхода метана и глубины минерализации органического вещества, является актуальной задачей. В ходе проведенных исследований изучалось влияние предварительной обработки осадков сточных вод в аппарате вихревого слоя ферромагнитных частиц на эффективность и кинетические параметры последующего анаэробного сбраживания осадка в термофильных условиях. Проведен анализ гранулометрического состава осадков сточных вод до и после обработки в аппарате вихревого слоя. Технологические параметры обработки осадков в аппарате вихревого слоя обусловили увеличение выхода метана на 3, степени разложения органического вещества на 8 9 и константы гидролиза на 4,7. Для оценки кинетических параметров процесса были использованы модифицированное уравнение Гомперца и уравнение первого порядка.Improving the efficiency of anaerobic digestion of wastewater sludge including methane yield and the depth of mineralization of organic matter increasing is an urgent task. As part of the study the effect of wastewater sludge pretreatment in an apparatus with vortex layer of ferromagnetic particles on the efficiency and kinetic parameters of the subsequent anaerobic digestion of the sludge under thermophilic conditions was investigated. The analysis of the particle size distribution of wastewater sludge before and after treatment in the vortex layer apparatus was carried out. The technological parameters of sludge processing in the vortex layer apparatus provided for increasing methane yield by 3, degree of decomposition of organic matter by 8 9, and hydrolysis constants by 4.7. To estimate the kinetic parameters of the process the modified Gompertz equation and the firstorder equation were used.

Sign in / Sign up

Export Citation Format

Share Document