Papers by Keyword: Biogas

Abstract: This study investigates the production of biogas through the co-anaerobic digestion of cow dung and sawdust, utilizing thermochemical pretreatment to enhance lignin breakdown. A 50:50 and a 75:25 mixture of the substrates (Cowdung:sawdust) were subjected to sodium hydroxide pretreatment and thermal conditioning at 80°C. Lignin content reduced from 31.94% to 22.73%. The results demonstrated approximately a 43% increase in biogas yield for both the 50:50 and 75:25 substrate ratios. A four-day earlier gas production onset was recorded for pretreated substrates compared to untreated samples. The methane content of the biogas reached 56% (50:50 ratio) and 60% (75:25 ratio), with hydrogen sulfide at about 1% in both ratios. Process parameters such as pH, and temperature were measured. This study provides a scalable approach for waste-to-energy applications and demonstrates the role of pretreatment in improving substrate digestibility and biogas yield.

Abstract: The remediation of palm oil mill effluent (POME) presents a considerable hurdle for Malaysia’s palm oil mill, requiring fulfillment with the environmental regulations before discharge. This work demonstrated a semiconductor-mediated photocatalytic technology to treat POME and synchronously evaluated the biogas generation. X-ray diffraction findings indicated that the fabricated ZnO product possessed wurtzite as a major crystalline phase. Its band gap energy was measured to be 3.27 eV via a UV-vis diffuse reflectance spectroscopy technique. The hierarchical ZnO microsphere morphology assembled by lots of layered nanosheets was observed via field-emission scanning electron microscopy. Under UV irradiation, the as-fabricated ZnO product displayed an enhanced photoactivity in comparison to the commercially available TiO₂ in treating the POME. Moreover, the ZnO/Ce and ZnO/Eu were also fabricated and showed greater photocatalytic efficacy after doping the rare earth ion in ZnO. Remarkably, the evaluation of biogas generation depicted that the ZnO/Ce and ZnO/Eu photocatalysis produced a greater quantity of CH₄ and CO₂ after 360 min irradiation. The work offered an environmentally friendly and efficient photocatalytic technology via ZnO/RE in treating wastewater and synchronously generating renewable energy.

Abstract: The palm oil industry is a large contributor to greenhouse gases in Indonesia. The application of biogas from the palm oil mill effluent (POME) treatment plant has become one of the solutions so it has been implemented at PT Agro Masang Perkasa (AMP). The catch of methane gasses is carried out by covering the waste pond with High-density Polyethylene (HDPE) material to create anaerobic conditions in the waste pool. The research results show that the methane gas obtained has been utilized as a renewable energy source such as biogas in factories with a total gas flow supplied to the engine of 135957, 121655, and 133736 Nm³ respectively, and an average power produced of 159.530, 153.168, and 160.161 MWh per month during observations in January, February, and March 2022. Although not all of the captured biogas is used for electrical energy, the benefits of implementing this technology mean that PT AMP has an average electricity efficiency in January, February, and March 2022 of 15.20 %, 22.49%, and 20.96%. Based on calculations, it is found that the use of methane capture or biogas technology at PT AMP can provide cost efficiency in a year of IDR. 5.21 billion and can return the installation capital within 3.5 years.

Abstract: The research was performed with the aim of obtaining new data on effective methanogenesis during the fermentation of sugar production waste with the addition of lignocellulosic raw materials. Amaranth crops of different varieties were used as raw materials. After analyzing the component composition of fresh amaranth and dry raw materials according to standard methods, the samples were subjected to microbiological processing in the presence of an enzyme preparation in laboratory and industrial conditions. It was determined that when using the vegetative mass of amaranth plants with waste from sugar production in the processes of methanogenesis, the yield of biogas and its caloric content increase.

Abstract: In recent years, particular attention has been paid to the use of renewable energy, particularly biomass, for reasons related to both climate change and waste management. Biogas is frequently used in low value-added applications such as heating and fuel in engines, while it can be reformed into hydrogen, through certain process such as the process of dry reforming, of partial oxidation, of bi-reforming, or even of tri-reforming. The literature has indicated that the tri-reforming process is better than other reforming processes. Biogas tri-reforming is a simultaneous combination of endothermic dry reforming and steam reforming with exothermic methane oxidation, carried out in a single reactor to produce syngas which is an important feedstock for chemical production and energy vectors. Second, the process of tri-reforming overcomes several weaknesses of each main reform process. This article presents a new mathematical model of tri-reforming which will further optimize this type of process. The developed mathematical model was validated with literature data. Thus, the literature data used are among others, the optimal feed ratio in the tri-reforming process, CH₄/CO₂/H₂O/O₂ = 1:0.291:0.576:0.088. For optimal temperature and pressure, the data used are 1223 K and 5 bar respectively. This mathematical model makes it possible to achieve high conversion of methane (CH₄) and carbon dioxide (CO₂) coupled with high selectivity in hydrogen. The conversion rate of methane (CH₄) can reach 99% and that of carbon dioxide (CO₂) can reach 97%. The model is adapted with a high hydrogen selectivity: 2.88.

Abstract: This examination talks about the potential for natural fluid waste to be utilized as a wellspring of electrical energy. The fluid waste produced from the processingof palm oil factories discharges methane into the air, causing a nursery impact which is harmful to the climate. Then again, methane contains potential as a source of electrical energy.This research was conducted quantitatively as all out energy investigation and analysis of the economic viability of biogas use in Rantau sub-district using Homer Energy software. Overall, the feasibility of development for the biogas power plant is carried out based on the supply of raw materials and electricity demand, with an estimated total investment is around 65.8 M and operational costs 5.4 M/year.

Abstract: Anaerobic digestion or anaerobic digestion is a biological process of degradation of organic matter in an anaerobic environment. It involves the degradation and stabilization of complex organic matter by a consortium of micro-organisms leading to methane-rich biogas that can be used as an alternative energy to fossil fuels. In addition, the use of biogas allows for the preservation of the environment and the sustainable development of rural areas and landlocked regions, as well as the diversification of energy resources, but also contributes to the development of agriculture through the production of organic fertilizer. In 2018, Senegal was ranked as the 15th world exporter of cashew nuts with a production of around 18,000 tons per year according to a study by PADEC (Support Program for the Development of Casamance). Four regions mainly invest in it: Kolda, Ziguinchor, Sédhiou, and Fatick. However, in the natural region of Casamance ( Kolda, Ziguinchor, and Sédhiou), each year, after the cashew nut campaign, more than 342,000 tons of cashew apples, pressed or not, are rejected without any recovery, thus degrading in the environment. In addition, rice is traditionally grown in Casamance and in some Diola circles, it had become one of the criteria of wealth, which explains why it occupied most of the cultivated areas and each year thousands of tons of rice husk are burned for elimination/reduction without any recovery. These immense annual productions of waste, without any recovery, in a context dominated by a deficit in cooking and lighting energy constitutes a form of energy resilience and motivates us to study the co-digestion of the rice husk (with a report of C/N equal to 101.317) on cashew apple pulp (having a C/N ratio of 23.201 ). The study of the co-digestion of rice husk and apple pulp at the laboratory scale with the inoculum reveals, that the co-digestion with pH correction contains 39.40% methane and 51.50% carbon dioxide after 49 days of production and 64.04% methane (CH₄) and 25.86% carbon dioxide (CO₂) on the 96th day. For co-digestion without adjustment, production stopped on the 49th day with a production of 23.68% methane and 45.65% carbon dioxide.

Abstract: There are many facets to the applications of Artificial Intelligence (AI) in the energy sector however, this research focuses on the utilization of Artificial Neural Networks (ANN) as parts of AI technique to simulate and model the operating performance of an industrial biogas plant data set. In this study, eight (8) model network architectures were developed using the ANN tool of MATLAB 2016a version and it was found that the best result was obtained based on the model performance evaluation metrics used such as Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE), Mean Absolute Deviation (MAD) and Determination Coefficient (R²) was as a result of the combination of two activation functions namely: tansig and logsig. The model, that produced the best result was a result of the architecture that contains 2 hidden neurons and the training algorithm of Scaled Conjugate Gradient (SCG). It was also observed that the ANN-predicted network diagram is better than the observed.

Abstract: In this study, the performance of dielectric barrier discharge (DBD) integrated with the aerobic process with the input voltage of 20 and 25 kV on the production of biogas; methane (CH₄), hydrogen (H₂), and carbon dioxide (CO₂) from palm oil mill effluent (POME) were investigated. The DBD and DBD integrated with the aerobic process (DBD + aerobic) treatment was also simulated using the theoretical stoichiometric of POME (in terms of carbohydrate) and the kinetic study using the first- and second-order kinetic model. The results showed only 0.58, 0.39, and 0.97 mol/L of CH₄, H_2, and CO₂, respectively, generated from the simulation model, which underperformed those experimental results. This may be due to the low concentration of carbohydrates given by the simulated stoichiometric reaction. However, both simulation and experimental results showed a rapid increase in biogas concentration in the initial reaction time in the DBD + aerobic reactor with an input voltage of 25 kV. The results showed that DBD + reactor produced CH₄, H_2, and CO₂ thirteen, twenty-three, and three times higher than DBD alone, respectively. This suggests that good performance was observed when the DBD was integrated with the aerobic process under the optimum input voltage. The study can give information on the optimum condition in a lab scale to produce CH₄, H_2, and CO₂ from POME.

Abstract: Biogas has been effectively produced from solid as well as liquid biomass waste through anaerobic digestion (AD). It has been proved that AD is the most efficient technology and less environmental effect in converting biomass to biogas. However, it is challenging that the rate of biogas production might slow down by many factors. It requires continues research in order to overcome the problem, such as by adding an additive. The use of several additives for AD has received great attention due to the positive influence in improving the production performance of biogas in terms of process stability and efficiency, and production capacity. Among all types of additives, carbon material in the form of bio-char has been considered as the most profitable due to low cost and easy to produce from various carbon source materials. This study aimed to determine the characteristics of coffee pulp bio-char which will be used as an additive in biogas production from coffee mucilage by the AD method. Coffee pulp biomass and coffee mucilage were obtained from Aceh Tengah, Indonesia. Preparation of bio-char was carried out by washing and soaking of the coffee pulp with tap water for 24 hours, then drying under the sun for three days. Carbonization of dried coffee pulp was then performed using a pilot plant-scale pyrolysis reactor at temperature of 400 °C for 60 minutes. Resulting biochar was then ground and sieved to 60 mesh size. Based on to proximate analysis result, it was found that the moisture, ash, volatile matter, and fixed carbon contents were respectively 1.98%, 11.93%, 42.36%, and 43.72%. N₂-physisorption analysis of coffee-pulp bio-char suggested pore volume of 0.21 cm³/g. From BET calculation method it was found that the surface area was 224.1 m²/g. This high surface area is beneficial for providing sheltered spaces for microbes to attach and hindering them against metabolic inhibitors. The effect of adding biochar additives from coffee skin waste in the anaerobic digestion process of coffee mucilage waste provides significant results on the yield of biogas products. The yield of biogas products increased by 225% with the addition of 15 gr/L of biochar coffee pulp.