scholarly journals Coupling of Anaerobic Digestion and Struvite Precipitation in the Same Reactor: Effect of Zeolite and Bischofite as Mg2+ Source

2021 ◽  
Vol 9 ◽  
Author(s):  
N. Palominos ◽  
A. Castillo ◽  
L. Guerrero ◽  
R. Borja ◽  
C. Huiliñir
Keyword(s):  
Anaerobic Digestion ◽  
Anaerobic Digester ◽  
Methane Yield ◽  
Pig Manure ◽  
Lag Phase ◽  
Pig Slurry ◽  
Piggery Wastewater ◽  
Simultaneous Effect ◽  
Total Phosphorous ◽  
Methane Production Rate

The aim of this research was to assess the simultaneous effect of zeolite and bischofite on estruvite production in an anaerobic digester treating pig slurry as substrate. Three ratios (5:1, 6:1 and 7:1) of Mg-P were used for evaluating the effect of only bischofite on anaerobic digestion. For assessing the simultaneous effect of zeolite and bischofite on anaerobic digestion, three mass ratios of zeolite:bischofite (1, 5 and 10%) were used. As results, bischofite as Mg+2 source served to decrease the total phosphorous (TP) concentration in the anaerobic digestion of pig manure without affecting the maximum methane production rate or methane yield of the system. An average 82.5% TP removal was found in the reactors with bischofite during the first 5 days of digestion. Nevertheless, bischofite increased the lag-phase of the system. The simultaneous presence of zeolite and bischofite (1% ratio with respect to bischofite) caused a TP removal of 65.6% and increased the methane yield by up to 19.9% compared to a system without zeolite or bischofite. Thus, it is feasible to use bischofite and zeolite as enhancers for the simultaneous production of biogas and struvite inside an anaerobic digester treating piggery wastewater.

scholarly journals Innovations in anaerobic digestion: a model-based study

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Karol Postawa ◽  
Jerzy Szczygieł ◽  
Marek Kułażyński
Keyword(s):  
Mathematical Model ◽  
Anaerobic Digestion ◽  
Production Efficiency ◽  
Biogas Production ◽  
Biogas Plant ◽  
Methane Content ◽  
Pig Manure ◽  
Pig Slurry ◽  
Production Chain ◽  
The Impact

Abstract Background Increasing the efficiency of the biogas production process is possible by modifying the technological installations of the biogas plant. In this study, specific solutions based on a mathematical model that lead to favorable results were proposed. Three configurations were considered: classical anaerobic digestion (AD) and its two modifications, two-phase AD (TPAD) and autogenerative high-pressure digestion (AHPD). The model has been validated based on measurements from a biogas plant located in Poland. Afterward, the TPAD and AHPD concepts were numerically tested for the same volume and feeding conditions. Results The TPAD system increased the overall biogas production from 9.06 to 9.59%, depending on the feedstock composition, while the content of methane was slightly lower in the whole production chain. On the other hand, the AHPD provided the best purity of the produced fuel, in which a methane content value of 82.13% was reached. At the same time, the overpressure leads to a decrease of around 7.5% in the volumetric production efficiency. The study indicated that the dilution of maize silage with pig manure, instead of water, can have significant benefits in the selected configurations. The content of pig slurry strengthens the impact of the selected process modifications—in the first case, by increasing the production efficiency, and in the second, by improving the methane content in the biogas. Conclusions The proposed mathematical model of the AD process proved to be a valuable tool for the description and design of biogas plant. The analysis shows that the overall impact of the presented process modifications is mutually opposite. The feedstock composition has a moderate and unsteady impact on the production profile, in the tested modifications. The dilution with pig manure, instead of water, leads to a slightly better efficiency in the classical configuration. For the TPAD process, the trend is very similar, but the AHPD biogas plant indicates a reverse tendency. Overall, the recommendation from this article is to use the AHPD concept if the composition of the biogas is the most important. In the case in which the performance is the most important factor, it is favorable to use the TPAD configuration.

scholarly journals Evaluation on the Methane Production Potential of Wood Waste Pretreated with NaOH and Co-Digested with Pig Manure

Catalysts ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 539 ◽  
Author(s):  
Renfei Li ◽  
Wenbing Tan ◽  
Xinyu Zhao ◽  
Qiuling Dang ◽  
Qidao Song ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Lignocellulosic Biomass ◽  
Methane Production ◽  
Biogas Production ◽  
Untreated Wood ◽  
Wood Waste ◽  
Methane Yield ◽  
Pig Manure ◽  
Naoh Pretreatment ◽  
Digestion Technique

Wood waste generated during the tree felling and processing is a rich, green, and renewable lignocellulosic biomass. However, an effective method to apply wood waste in anaerobic digestion is lacking. The high carbon to nitrogen (C/N) ratio and rich lignin content of wood waste are the major limiting factors for high biogas production. NaOH pre-treatment for lignocellulosic biomass is a promising approach to weaken the adverse effect of complex crystalline cellulosic structure on biogas production in anaerobic digestion, and the synergistic integration of lignocellulosic biomass with low C/N ratio biomass in anaerobic digestion is a logical option to balance the excessive C/N ratio. Here, we assessed the improvement of methane production of wood waste in anaerobic digestion by NaOH pretreatment, co-digestion technique, and their combination. The results showed that the methane yield of the single digestion of wood waste was increased by 38.5% after NaOH pretreatment compared with the untreated wood waste. The methane production of the co-digestion of wood waste and pig manure was higher than that of the single digestion of wood waste and had nonsignificant difference with the single-digestion of pig manure. The methane yield of the co-digestion of wood waste pretreated with NaOH and pig manure was increased by 75.8% than that of the untreated wood waste. The findings indicated that wood waste as a sustainable biomass source has considerable potential to achieve high biogas production in anaerobic digestion.

Effect of sodium salt on anaerobic digestion of kitchen waste

2016 ◽  
Vol 73 (8) ◽  
pp. 1865-1871 ◽  
Author(s):  
Naveed Anwar ◽  
Wen Wang ◽  
Jie Zhang ◽  
Yeqing Li ◽  
Chang Chen ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Sodium Salt ◽  
Salt Concentration ◽  
Methane Production ◽  
Volatile Fatty Acids ◽  
Production Performance ◽  
Methane Yield ◽  
Production Model ◽  
Lag Phase ◽  
Kitchen Waste

The effect of different sodium salt concentration on anaerobic digestion of kitchen waste was investigated. The methane production performance, the corresponding methane production model and sodium salt inhibition model were studied, and the degradation efficiency was analyzed. With the increase of sodium salt concentration, the methane yield and the maximal methane production rate decreased along with the increase of lag phase time. The highest methane yield of 594 mL/g-VSadded (VS: volatile solids) was found with no sodium salt addition while the lowest was obtained with addition of 16 g/L NaCl. The declines of the methane yield were negligible when the sodium salt concentration was below 8 g/L, which corresponded to <10% inhibiting efficiency. In contrast, a sharp decrease of methane yield was observed with addition of >8 g/L NaCl (causing 17–80% inhibition). Five kinds of regression models were developed to describe the sodium salt inhibition efficiency, and the cubic regression model of y = 0.508 + 2.401x − 0.369x2 + 0.033x3 showed the best fitting. The volatile fatty acids/ethanol gradually accumulated along with the increase of the sodium salt concentration, and the volatile solid removal efficiency represented a gradual decline accordingly. It is recommended that the sodium salt concentration in the anaerobic digesters should be controlled below 8 g/L in order to avoid intense methane inhibition.

scholarly journals Succession of microbial community in anaerobic digestion of dairy manure induced by manure-derived biochar

2020 ◽  
Vol 26 (1) ◽  
Author(s):  
Hyun Min Jang ◽  
Jeff Brady ◽  
Eunsung Kan
Keyword(s):  
Electron Transfer ◽  
Microbial Community ◽  
Anaerobic Digestion ◽  
Community Analysis ◽  
Dairy Manure ◽  
Microbial Community Analysis ◽  
Methane Yield ◽  
Lag Phase ◽  
Interspecies Electron Transfer ◽  
Syntrophic Bacteria

The present study investigates possible roles of manure-derived biochar (MBC) in anaerobic digestion (AD) of dairy manure. Addition of MBC led to an increase in cumulative methane yield and a decrease in lag phase under all tested conditions (concentration of MBC: 1 and 10 g/L, temperature: 20, 35 and 55°C). For example, the cumulative methane yield in the mesophilic AD with 10 g/L MBC were 24.51% higher than that of the AD without MBC. Additionally, lag phage of mesophilic AD with 10 g/L MBC decreased from 2.08 d to 1.52 d. Microbial community analysis indicated that the addition of MBC to mesophilic and thermophilic AD of dairy manure increased the relative abundance of <i>Ruminofilibacter</i> which related to the hydrolysis. In addition, the addition of MBC to AD potentially stimulated the growth of syntrophic bacteria (e.g., genera Clostridium, Syntrophomonas and Syntrophus) and hydrogenotrophic methanogens (e.g., genera <i>Methanobacterium, Methanolinea</i> and <i>Methanomassiliicoccus</i>). Furthermore, microbial community analysis also suggested that mediate interspecies electron transfer and direct interspecies electron transfer would be accelerated by addition of MBC which showed high electrical conductivity (3230 μS/cm).

Experimental and Modelling Approach of Biogas Production by Anaerobic Digestion of Agricultural Resources

2017 ◽  
Vol 68 (6) ◽  
pp. 1294-1297 ◽  
Author(s):  
Gabriela Alina Dumitrel ◽  
Adrian Eugen Cioabla ◽  
Ioana Ionel ◽  
Lucia Ana Varga
Keyword(s):  
Anaerobic Digestion ◽  
Methane Production ◽  
Biogas Production ◽  
Batch Reactor ◽  
Pilot Scale ◽  
Lag Phase ◽  
Biogas Yield ◽  
Agricultural Resources ◽  
Methane Production Rate ◽  
Modelling Approach

Anaerobic digestion processes of agricultural resources, as single substrates (wheat bran and barley) or as combination of substrates (75 % corn&25% corn cob � named MIX1 and 40 % corn & 40 % wheat&20 % sunflower husks � named MIX2), were performed, at a mesophilic temperature in a batch reactor, at pilot scale. The results proved that the higher quantity of biogas yield was achieved for barley, followed by MIX1, and finally MIX2. The same order was obtained when the total methane production was evaluated. The performances of digesters were mathematically evaluated by using the modified Gompertz equation. The kinetic parameters, such as the methane production potential (MP), the maximum methane production rate (Rm) and the extent of lag phase (l) were calculated, for each experimental case. The values of the performance indicators confirmed that all the models fitted well with the experimental data.

Relationship of Substrate and Inoculum on Biochemical Methane Potential for Grass and Pig Manure Co-Digestion

2012 ◽  
Vol 512-515 ◽  
pp. 444-448 ◽  
Author(s):  
Sumeth Dechrugsa ◽  
Sumate Chaiprapat
Keyword(s):  
Methane Production ◽  
Methane Yield ◽  
Pig Manure ◽  
Biochemical Methane Potential ◽  
Production Potential ◽  
Methane Potential ◽  
Methane Production Rate ◽  
Substrate Ratio ◽  
Relationship Of ◽  
Careful Investigation

The effects of substrate mix ratio and inoculum/substrate ratio (ISR) on biochemical methane potential of para-grass (PG) and pig manure (PM) were investigated in batch test that maintained temperature at 35±1 oC and continuously shaked at 120 rpm. Cumulative methane production data at different mix ratios and ISRs were evaluated and fitted with Gompertz equation to derive methane production potential (mL) and maximum methane production rate (mL/d). The maximum and average methane yields at each respective ISR of 1, 2, 3, and 4 were [413.0, 315.5], [539.7, 455.6], [590.3, 472.5], and [593.1, 473.5] mL/gVSadded. Relationship of ISR and PG mix ratio to specific methane yield were expressed in quadratic regression model. The generated response surface showed that methane yield was elevated at higher ISR and higher PG mix ratio. This suggests a careful investigation at different ISR and substrate mix ratios should be performed in order to develop a realistic biochemical methane potential of anaerobic co-digestion.

Study of the biological N removal over nitrite in a physico-chemical-biological treatment of digested pig manure in a SBR

2008 ◽  
Vol 58 (1) ◽  
pp. 119-125 ◽  
Author(s):  
J. Dosta ◽  
S. López-Palau ◽  
J. Mata-Álvarez
Keyword(s):  
Anaerobic Digestion ◽  
Biological Treatment ◽  
Oxygen Supply ◽  
Pig Manure ◽  
Biological Nitrogen Removal ◽  
Piggery Wastewater ◽  
N Removal ◽  
Physico Chemical ◽  
Biomass Activity ◽  
Biological Nitrogen

SBR technology is used to treat the supernatant from mesophilic anaerobic digestion of piggery wastewater. The novelty of the treatment consists in the use of a final coagulation/flocculation step inside the SBR cycle to reach the legal COD effluent standard. The pH changes introduced by the use of FeCl3 do not affect the nitrifying activity. The SBR treatment includes a strategy to the control of oxygen supply and ammonia concentrations inside the digester to favor the biological nitrogen removal over nitrite, which makes the process more economical. The influence of several of these parameters on the AOB biomass activity is studied in this paper.

Influence of mix ratio of potato peel and pig manure on reaction kinetics and methane recovery from anaerobic co-digestion

2021 ◽  
Author(s):  
Tolulope Adeleye ◽  
Hyeongu Yeo ◽  
Hisham Hafez ◽  
Rajesh Seth ◽  
Nihar Biswas
Keyword(s):  
Reaction Kinetics ◽  
Production Rate ◽  
Methane Production ◽  
Methane Yield ◽  
Pig Manure ◽  
Potato Peel ◽  
Methane Recovery ◽  
Digestion Process ◽  
Methane Production Rate ◽  
Potential Improvement

The potential improvement in methane recovery and reaction kinetics from different mixes of potato peel (PP) and pig manure (PM) in a single stage anaerobic co-digestion/mono-digestion process was investigated in a laboratory study. The highest methane yield of 231 mL/g TCODadded was observed in the 50:50 mix of potato peel and pig manure. Compared to the mono-digested substrates, co-digestion of PP and PM at 75:25, 50:50 and 25:75 synergistically improved methane yield by 17%, 25% and 11%, respectively. The co-digested mixes also produced methane at a faster rate, with the fastest methane production rate occurring at the 50:50 mix. Thus, co-digestion of potato peel and pig manure enhanced the methane yield and reaction kinetics. Hence, co-digestion rather than mono-digestion should be actively considered when a carbon rich waste (such as potato peel) and nutrient rich waste (such as pig manure) are available within reasonable proximity.

scholarly journals Anaerobic Co-digestion of Rice Straw and Pig Manure Pretreated With a Cellulolytic Microflora: Methane Yield Evaluation and Kinetics Analysis

2021 ◽  
Vol 8 ◽  
Author(s):  
Bin Zhong ◽  
Xuejiao An ◽  
Fei Shen ◽  
Weijuan An ◽  
Qinghua Zhang
Keyword(s):  
Rice Straw ◽  
Methane Production ◽  
Methane Yield ◽  
Energy Output ◽  
Organic Loading Rate ◽  
Pig Manure ◽  
Control Group ◽  
Lag Phase ◽  
Net Energy ◽  
Order Kinetic

Agricultural wastes, such as rice straw (RS) and pig manure (PM), cause serious environmental pollution due to the non-existence of effective disposal methods. Urgent investigations are needed to explore how such wastes can be transformed into resources. In this study, we comprehensively assessed methane yield and kinetics of RS and PM anaerobic co-digestion, with or without pretreatment of a previously developed cellulolytic microflora, under conditions of their maximum organic loading rate. The anaerobic co-digestion results revealed that the cumulative methane production of RS and PM after bio-pretreatment was 342.35 ml (g-VS)−1, which is 45% higher than that of the control group [236.03 ml·(g-VS)−1]. Moreover, the kinetic analysis showed the first-order kinetic, while the modified Gompertz models revealed higher fitting properties (R2 ≥ 0.966). After bio-pretreatment, the hydrolytic constant, maximum accumulative methane production, and maximum methane production rates of RS and PM reached 0.46 day−1, 350.79 ml·(g-VS)−1, and 45.36 ml·(g-VS)−1·day−1, respectively, which were 77, 45.1, and 84.3% higher than those without pretreatment. Also, we found that the lag phase and effective methane production time after bio-pretreatment decreased from 2.43 to 1.79 days and 10.7 to 8.92 days, respectively. Upon energy balance evaluation, we reported a net energy output of 5133.02 kWh·ton−1 after bio-pretreatment. Findings from this present study demonstrated that bio-pretreatment of RS and PM mixtures with cellulolytic microflora could greatly enhance methane production and anaerobic digestion efficiency.

Anaerobic digestion of pig manure fibres from commercial pig slurry separation units

2014 ◽  
Vol 123 ◽  
pp. 91-96 ◽  
Author(s):  
Ole Thygesen ◽  
Jin M. Triolo ◽  
Sven G. Sommer
Keyword(s):  
Anaerobic Digestion ◽  
Pig Manure ◽  
Pig Slurry
Sign in / Sign up

Export Citation Format

Share Document