scholarly journals Biogas Potential of Coffee Processing Waste in Ethiopia

2018 ◽  
Vol 10 (8) ◽  
pp. 2678 ◽  
Author(s):  
Bilhate Chala ◽  
Hans Oechsner ◽  
Sajid Latif ◽  
Joachim Müller
Keyword(s):  
Waste Water ◽  
Thermal Energy ◽  
Anaerobic Fermentation ◽  
Combined Heat And Power ◽  
Neutral Detergent Fiber ◽  
Anaerobic Performance ◽  
Processing Waste ◽  
Biochemical Methane Potential ◽  
Methane Potential ◽  
The Mean

Primary coffee processing is performed following the dry method or wet method. The dry method generates husk as a by-product, while the wet method generates pulp, parchment, mucilage, and waste water. In this study, characterization, as well as the potential of husk, pulp, parchment, and mucilage for methane production were examined in biochemical methane potential assays performed at 37 °C. Pulp, husk, and mucilage had similar cellulose contents (32%). The lignin contents in pulp and husk were 15.5% and 17.5%, respectively. Mucilage had the lowest hemicellulose (0.8%) and lignin (5%) contents. The parchment showed substantially higher lignin (32%) and neutral detergent fiber (96%) contents. The mean specific methane yields from husk, pulp, parchment, and mucilage were 159.4 ± 1.8, 244.7 ± 6.4, 31.1 ± 2.0, and 294.5 ± 9.6 L kg−1 VS, respectively. The anaerobic performance of parchment was very low, and therefore was found not to be suitable for anaerobic fermentation. It was estimated that, in Ethiopia, anaerobic digestion of husk, pulp, and mucilage could generate as much as 68 × 106 m3 methane per year, which could be converted to 238,000 MWh of electricity and 273,000 MWh of thermal energy in combined heat and power units. Coffee processing facilities can utilize both electricity and thermal energy for their own productive purposes.

scholarly journals How Different Are Manometric, Gravimetric, and Automated Volumetric BMP Results?

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1839 ◽  
Author(s):  
Corrado Amodeo ◽  
Sasha D. Hafner ◽  
Rúben Teixeira Franco ◽  
Hassen Benbelkacem ◽  
Paul Moretti ◽  
...  
Keyword(s):  
Automated System ◽  
Biochemical Methane Potential ◽  
Ch4 Production ◽  
Automated Method ◽  
Validation Criteria ◽  
Relative Standard ◽  
Mode 2 ◽  
Methane Potential ◽  
Manual Methods ◽  
The Mean

The objectives of this study were to: (1) quantify differences in biochemical methane potential (BMP) measured using three measurement methods, including two popular methods (a commercial automated system (AMPTS II) and manual manometric) and one newer method (gravimetric), and (2) assess the importance of the mixing position in the measurement sequence. Powdered microcrystalline cellulose was used as the substrate in simultaneous tests. All methods gave similar results (<8% difference in the mean BMP) and were reasonably accurate (recovery of 80–86% of the theoretical maximum BMP). Manometric BMP values were consistently lower than gravimetric by 4–5%. Precision was lower for the automated method (relative standard deviation (RSD) of about 7%) than for the manual methods (RSD about 1–3%). Mixing after biogas measurement resulted in 3% higher BMP for both manual methods than mixing before, due to the lower measured CH4 production from blanks. This effect may be linked to a fraction of CH4 that remains dissolved or even as attached bubbles, and suggests that mixing before measurement is preferable. The automated volumetric and gravimetric methods (mode 2) gave very similar mean BMP values (1% different). However, kinetic analysis showed that methane production was faster with the automated volumetric method. This could come from an error in the estimation of the CH4 production rate for the automated method, or an increase in the degradation rate due to better mixing. Both automatic volumetric and manual gravimetric measurements met current validation criteria for mean cellulose BMP, but the RSD from the automated system exceeded the limit.

scholarly journals Comparing Low-Temperature Hydrothermal Pretreatments through Convective Heating versus Microwave Heating for Napier Grass Digestion

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1221
Author(s):  
Kanyarat Saritpongteeraka ◽  
Jutawan Kaewsung ◽  
Boonya Charnnok ◽  
Sumate Chaiprapat
Keyword(s):  
Waste Heat ◽  
Combined Heat And Power ◽  
Napier Grass ◽  
Convective Heating ◽  
Quadratic Regression ◽  
Biochemical Methane Potential ◽  
Microwave Exposure ◽  
Methane Potential ◽  
Biomethane Production ◽  
The Relationship

This study investigates the effects of convective hydrothermal pretreatment (CHTP) compared to microwave pretreatment (MWP) on the anaerobic digestion of hybrid Napier grass for biomethane production. For rapid estimation of methane yield (YCH4), enzymatic hydrolyzability (EH), whose test lasts only 2 days was used as a surrogate parameter instead of the biochemical methane potential (BMP) assay that normally takes 45–60 days. The relationship between EH and BMP was successfully modeled with satisfactory accuracy (R2 = 0.9810). From CHTP results, quadratic regression characterised by p < 0.0001 and R2 = 0.8364 shows that YCH4 increase was clearly sensitive to detention time at all CHTP temperatures. The maximal YCH4 achieved of 301.5 ± 3.0 mL CH4/gVSadd was 53.2% higher than the control. Then, MWP was employed at various power levels and microwave exposure times. Changes in lignocellulosic structure by Fourier-transform infrared spectroscopy (FTIR) and energy balance demonstrate that MWP caused more damage to plant cells, which proved more effective than CHTP. In the best conditions, approximately 50% of energy was needed for MWP to achieve the equivalent improvement in YCH4. However, CHTP is a more suitable option since waste heat, i.e., from a biogas CHP (combined heat and power) unit, could be used, as opposed to the electricity required for MWP.

scholarly journals The use of out-of-date frozen food as a substrate for biogas in anaerobic methane fermentation

2018 ◽  
pp. 67-75
Author(s):  
Damian Pietrzyk ◽  
Anna Klepacz-Smółka
Keyword(s):  
Fossil Fuels ◽  
Fermentation Process ◽  
Near Infrared ◽  
Anaerobic Fermentation ◽  
Clean Energy ◽  
Biochemical Methane Potential ◽  
Methane Fermentation ◽  
Frozen Food ◽  
Methane Potential ◽  
Increasing Demand

The declining quantity of fossil fuels and the increasing demand for energy are two of the many problems that are affecting current times. This is why there is an increasing interest in and introduction of operations related to renewable sources of energy. One of many such possibilities is to conduct the biomass methane fermentation process and to obtain clean energy in the form of biogas. The aim of this research was to analyse the biogas-generating potential (Biochemical Methane Potential) of out-of-date frozen products in the laboratory anaerobic fermentation process and the near-infrared method with appropriate Biochemical Methane Potential calibration. The results obtained showed that selected frozen products are an excellent material for use as substrates resulting in the production of high quality biogas. It gives the opportunity to continue research, mainly in terms of applications, e.g. for biogas plants, using other available products on the market and the selection of their mixtures.

INFLUENCE OF FREEZING/THAWING AND DRYING/MILLING ON BIOCHEMICAL METHANE POTENTIAL

2016 ◽  
Vol 15 (7) ◽  
pp. 1533-1536
Author(s):  
Jin Mi Triolo ◽  
Sven Gjedde Sommer ◽  
Lene Pedersen
Keyword(s):  
Biochemical Methane Potential ◽  
Methane Potential

scholarly journals Batch Anaerobic Co-Digestion and Biochemical Methane Potential Analysis of Goat Manure and Food Waste

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1952
Author(s):  
Ayobami Orangun ◽  
Harjinder Kaur ◽  
Raghava R. Kommalapati
Keyword(s):  
Food Waste ◽  
Gompertz Model ◽  
Water Displacement ◽  
Biochemical Methane Potential ◽  
Greenhouse Gasses ◽  
Nonlinear Regression Models ◽  
The Us ◽  
Methane Potential ◽  
Goat Manure ◽  
Modified Gompertz Model

The improper management of goat manure from concentrated goat feeding operations and food waste leads to the emission of greenhouse gasses and water pollution in the US. The wastes were collected from the International Goat Research Center and a dining facility at Prairie View A&M University. The biochemical methane potential of these two substrates in mono and co-digestion at varied proportions was determined in triplicates and processes were evaluated using two nonlinear regression models. The experiments were conducted at 36 ± 1 °C with an inoculum to substrate ratio of 2.0. The biomethane was measured by water displacement method (pH 10:30), absorbing carbon dioxide. The cumulative yields in goat manure and food waste mono-digestions were 169.7 and 206.0 mL/gVS, respectively. Among co-digestion, 60% goat manure achieved the highest biomethane yields of 380.5 mL/gVS. The biodegradabilities of 33.5 and 65.7% were observed in goat manure and food waste mono-digestions, while 97.4% were observed in the co-digestion having 60% goat manure. The modified Gompertz model is an excellent fit in simulating the anaerobic digestion of food waste and goat manure substrates. These findings provide useful insights into the co-digestion of these substrates.

scholarly journals Rapid Biochemical Methane Potential Evaluation of Anaerobic Co-Digestion Feedstocks Based on Near Infrared Spectroscopy and Chemometrics

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1460
Author(s):  
Jinming Liu ◽  
Changhao Zeng ◽  
Na Wang ◽  
Jianfei Shi ◽  
Bo Zhang ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Variable Selection ◽  
Root Mean Square Error ◽  
Least Squares ◽  
Mean Square Error ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Mean Square ◽  
Biochemical Methane Potential ◽  
Methane Potential

Biochemical methane potential (BMP) of anaerobic co-digestion (co-AD) feedstocks is an essential basis for optimizing ratios of materials. Given the time-consuming shortage of conventional BMP tests, a rapid estimated method was proposed for BMP of co-AD—with straw and feces as feedstocks—based on near infrared spectroscopy (NIRS) combined with chemometrics. Partial least squares with several variable selection algorithms were used for establishing calibration models. Variable selection methods were constructed by the genetic simulated annealing algorithm (GSA) combined with interval partial least squares (iPLS), synergy iPLS, backward iPLS, and competitive adaptive reweighted sampling (CARS), respectively. By comparing the modeling performances of characteristic wavelengths selected by different algorithms, it was found that the model constructed using 57 characteristic wavelengths selected by CARS-GSA had the best prediction accuracy. For the validation set, the determination coefficient, root mean square error and relative root mean square error of the CARS-GSA model were 0.984, 6.293 and 2.600, respectively. The result shows that the NIRS regression model—constructed with characteristic wavelengths, selected by CARS-GSA—can meet actual detection requirements. Based on a large number of samples collected, the method proposed in this study can realize the rapid and accurate determination of the BMP for co-AD raw materials in biogas engineering.

scholarly journals Biochemical Methane Potential of Cork Boiling Wastewater at Different Inoculum to Substrate Ratios

2021 ◽  
Vol 11 (7) ◽  
pp. 3064
Author(s):  
Roberta Mota-Panizio ◽  
Manuel Jesús Hermoso-Orzáez ◽  
Luis Carmo-Calado ◽  
Gonçalo Lourinho ◽  
Paulo Sérgio Duque de Brito
Keyword(s):  
Anaerobic Digestion ◽  
Biogas Production ◽  
Treatment Plant ◽  
Organic Substrates ◽  
Biochemical Methane Potential ◽  
Volatile Solids ◽  
Working Volume ◽  
Methane Potential ◽  
Bmp Test ◽  
Cork Industry

The present study evaluates the digestion of cork boiling wastewater (CBW) through a biochemical methane potential (BMP) test. BMP assays were carried out with a working volume of 600 mL at a constant mesophilic temperature (35 °C). The experiment bottles contained CBW and inoculum (digested sludge from a wastewater treatment plant (WWTP)), with a ratio of inoculum/substrate (Ino/CBW) of 1:1 and 2:1 on the basis of volatile solids (VSs); the codigestion with food waste (FW) had a ratio of 2/0.7:0.3 (Ino/CBW:FW) and the codigestion with cow manure (CM) had a ratio of 2/0.5:0.5 (Ino/CBW:CM). Biogas and methane production was proportional to the inoculum substrate ratio (ISR) used. BMP tests have proved to be valuable for inferring the adequacy of anaerobic digestion to treat wastewater from the cork industry. The results indicate that the biomethane potential of CBWs for Ino/CBW ratios 1:1 and 2:1 is very low compared to other organic substrates. For the codigestion tests, the test with the Ino/CBW:CM ratio of 2/0.7:0.3 showed better biomethane yields, being in the expected values. This demonstrated that it is possible to perform the anaerobic digestion (AD) of CBW using a cosubstrate to increase biogas production and biomethane and to improve the quality of the final digestate.

scholarly journals Optimizing anaerobic co-digestion of goat manure and cotton gin trash using biochemical methane potential (BMP) test and mathematical modeling

2021 ◽  
Vol 3 (8) ◽  
Author(s):  
Harjinder Kaur ◽  
Raghava R. Kommalapati
Keyword(s):  
Liquid Fraction ◽  
Gompertz Model ◽  
Biochemical Methane Potential ◽  
Methane Potential ◽  
Mathematical Equations ◽  
Goat Manure ◽  
Bmp Test ◽  
Batch Bioreactors ◽  
Modified Gompertz Model ◽  
Cotton Gin

AbstractAnaerobic co-digestion is widely adopted to enhance process efficacy by balancing the C/N ratio of the feedstock while converting organic wastes to biomethane. Goat manure (GM) and cotton gin trash (CGT) were anaerobically co-digested in triplicate batch bioreactors. The process was optimized and evaluated utilizing mathematical equations. The liquid fraction of the digestate was analyzed for nitrate and phosphate. The co-digestions with 10 and 20% CGT having the C/N ratios of 17.7 and 19.8 yielded the highest and statistically similar 261.4 ± 4.8 and 262.6 ± 4.2 mL/gvs biomethane, respectively. The biodegradability (BD) of GM and CGT was 94.5 ± 2.7 and 37.6 ± 0.8%, respectively. The BD decreased proportionally with an increase in CGT percentage. The co-digestion having 10% CGT yielded 80–90% of biomethane in 26–39 d. The modified Gompertz model-predicted and experimental biomethane values were similar. The highest synergistic effect index of 15.6 ± 4.7% was observed in GM/CGT; 30:70 co-digestion. The concentration of nitrate and phosphate was lower in the liquid fraction of digestate than the feedstocks, indicating that these nutrients stay in the solid fraction. The results provide important insights in agro-waste management, further studies determining the effects of effluent application on plants need to be conducted.

Sign in / Sign up

Export Citation Format

Share Document