Renewable Energy Resources and Technologies
Ali Nazari; Morteza Hosseinpour; Mahdi Rezaei
Abstract
In this study, the impact of digestate treatment after Anaerobic Digestion (AD) process in two scenarios is analyzed in the case of an industrial diary unit in the United States. The first scenario involves production of liquid fertilizer and compost, while the second scenario lacks such a treatment ...
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In this study, the impact of digestate treatment after Anaerobic Digestion (AD) process in two scenarios is analyzed in the case of an industrial diary unit in the United States. The first scenario involves production of liquid fertilizer and compost, while the second scenario lacks such a treatment process. Aspen Plus is used to simulate the AD process and evaluate the general properties of biogas and digestate. The results of technical analysis show insignificant changes in the net power production from the CHP unit in Scenario 1. The economic analysis, however, indicates the necessity of digestate treatment for AD systems to be profitable. Furthermore, the results of environmental analysis indicate the mitigation of about 93.4 kilotonnes of greenhouse gas (GHG) emissions in Scenario 1, while AD in Scenario 2 saves only 12 kilotonnes of GHG emissions. In other words, digestate treatment has a more significant environmental impact than the power production and its profitability from CHP unit. The reason could be attributed to the enormous consumption of energy during the production of chemical fertilizers where the digestate treatment process (scenario 1) offsets the utilization of chemical fertilizers in the agriculture industry.
Renewable Energy Resources and Technologies
Uttam Bista; Bhawana Rayamajhi; Bipasyana Dhungana; Sunil Prasad Lohani
Abstract
Anaerobic digestion is one of the most effective technologies for managing degradable waste, which produces renewable energy and digestate as the byproduct. In this study, sewage sludge (SS), poultry litter (PL), and food waste (FW) were co-digested at ratios (SS:PL:FW 2:1:1) with 8 % total solid content ...
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Anaerobic digestion is one of the most effective technologies for managing degradable waste, which produces renewable energy and digestate as the byproduct. In this study, sewage sludge (SS), poultry litter (PL), and food waste (FW) were co-digested at ratios (SS:PL:FW 2:1:1) with 8 % total solid content at ambient temperature (average 22 °C) and controlled temperature (35 °C) in summer. The synergistic effects of co-digesting substrates enhance the biogas production potential when digested at an optimized ratio. The maximum biogas yield was 688.7 L/kgVSa at the controlled temperature and 462.3 L/kgVSa at ambient temperature. The ambient reactor had a methane composition of 55 %, while the controlled temperature reactor had about 60 %. The results provide approaches to increase biogas production in the anaerobic digestion process through co-digestion and controlled mesophilic temperature. Biogas production from anaerobic co-digestion could significantly transform waste into energy in low-income countries to achieve the objective of clean energy production and environmental sustainability.
Renewable Energy Resources and Technologies
Fatemeh Norouzi; Morteza Hosseinpour; Saeed Talebi
Abstract
In this paper, an industrial dairy farm unit was taken as a case study to carry out the applicable technical assessment for the construction of a biogas plant using a combined heat and power (CHP) unit. A comprehensive sensitivity analysis was applied to examine the effectiveness of the operational parameters ...
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In this paper, an industrial dairy farm unit was taken as a case study to carry out the applicable technical assessment for the construction of a biogas plant using a combined heat and power (CHP) unit. A comprehensive sensitivity analysis was applied to examine the effectiveness of the operational parameters and feed composition in the purity and production rate of biogas. Aspen Plus was used to implement the anaerobic digestion process. The results showed that any increase in the digester’s operational performance and mass rate of feedstock water led to the modification of biomethane content, but dropped in biogas mass flow rate. Moreover, an increase in the mass rate of carbohydrates, protein, and organic load rate (OLR) of feedstock reduces methane composition. Besides, increasing the rate of lipids has raised the rate of methane production and its composition.
Renewable Energy Resources and Technologies
Sapna Kinattinkara; Thangavelu Arumugam; Nandhini Samiappan; Vivek Sivakumar; Sampathkumar Velusamy; Mohanraj Murugesan; Manoj Shanmugamoorthy
Abstract
Increased global energy consumption demands the use of more energy resources, aggravating environmental issues. This study focused on analyzing biogas production from a mixture of cow dung, water hyacinth, and food waste and checking the efficiency of the biogas. The efficiency of biogas production was ...
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Increased global energy consumption demands the use of more energy resources, aggravating environmental issues. This study focused on analyzing biogas production from a mixture of cow dung, water hyacinth, and food waste and checking the efficiency of the biogas. The efficiency of biogas production was tested using two alternative settings in the study. The first setup employs Eichhornia crassipes that have been NaOH-treated and mixed with co-digestion substrates such as cow manure and food waste which have been stored at room temperature for 32 days. The second setup contains five different types of substrates such as L1-cow dung, L2- cow dung: water hyacinth, L3-cow dung: food waste, L4-cow dung: water hyacinth: food waste, and L5-water hyacinth. The properties of the Eichhornia crassipes were studied on several biogas substrates, such as pH, temperature, COD, TOC, and NPK tests, as well as total biogas output and methane percentage. The results of the comparison analysis show that the substrate L4 has a high level of NPK (4.7 %) and a higher amount of COD (137600 mg/l). These characteristics enhance the gas yield and methane percentage (85 %). Overall, the water hyacinth mixed with cow dung and food waste exceeded the other four substrates. The total yield of biogas from the first setup was 8.5 litres, the flammability was tested on the 28th day, and the blue flame was obtained. Water hyacinth was removed from aquatic areas and used as an alternative energy source, hence being environmentally friendly.
Advanced Energy Technologies
Shafini Mohd Shafie; Zakirah Othman; A. Harits Nu'man; Nik Nurul Anis Nik Yusuf
Abstract
Penetration of renewable energy in the energy generation mix must be viewed from different angles. This issue shall not only cover the technological part, but also economic, environmental, and social criteria. The fuel cell provides huge potential with less reliance on fossil fuel-based electricity generation. ...
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Penetration of renewable energy in the energy generation mix must be viewed from different angles. This issue shall not only cover the technological part, but also economic, environmental, and social criteria. The fuel cell provides huge potential with less reliance on fossil fuel-based electricity generation. This paper aims to model the optimum design of fuel cell-based electricity generation in Malaysia. Economic and environmental aspects are indicators that contribute to designing an optimum model. Both Multi-Criteria Analysis and Analytic Hierarchy Process were employed in order to decide on the optimum site for the system. Truck transportation, biogas storage, and fuel cell system are among the most important criteria that provide final weighted criteria. Considering both criteria for the economic and environment concerns, the best optimum location is in Sarawak State. The findings of this study influence the decision-making and help researchers and decision-makers develop proper strategies in the renewable energy roadmap.
Renewable Energy Resources and Technologies
Rasoul Aydram; Hossein Haji Agha Alizade; Majid Rasouli; Behdad Shadidi
Abstract
Reduced emissions of greenhouse gases and global warming can be made possible by discovering alternative energies and reduced dependence on fossil fuels. Biogas is considered as one of the alternatives to fossil fuels. This study investigates anaerobic co-digestion for the development of biogas with ...
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Reduced emissions of greenhouse gases and global warming can be made possible by discovering alternative energies and reduced dependence on fossil fuels. Biogas is considered as one of the alternatives to fossil fuels. This study investigates anaerobic co-digestion for the development of biogas with sheep blood and cheese whey. Digested cow manure was used as inoculum. Using the Design Expert 10 program and within the context of mixture design, the experiments were designed. Then, 22 experimental digesters with a volume of 500 mL were considered for doing the experiments considering the design output provided by the software. Each one was filled with 300 mL of different compositions of three matters. The digesters were kept in the mesophilic temperature range (37 °C ) for 21 days. Biogas was measured using the BMP test on a daily basis. According to the experimental findings, the best composition included 35 % sheep blood, 35 % cheese whey, and 30 % inoculum. This biogas composition produced a biogas yield of 146.66 mL/g vs. The amount of methane production in this compound was 73.33 mL/g vs. After modeling, the Design Expert software predicted an optimal composition including 44 % sheep blood, 24 % cheese whey, and 32 % inoculum. Biogas yield of this prediction was 143 mL/g vs. The findings show that in order to overcome acidification in digestion of matters such as cheese whey, a composition of matters with higher pH stability can be used to increase the amount of biogas and methane produced in a particular period. Furthermore, using inoculum accelerates the digestion operations due to existence of many microorganisms and saves time and energy.
Renewable Energy Economics, Policies and Planning
Maryam Nosratinia; Ali Asghar Tofigh; Mehrdad Adl
Abstract
Given the world’s growing population and energy demand, modern methods are developed to contribute to generating alternative energies. They aim to maintain the renewability of the supplied energy and decrease environmental contaminations. Biogas is a renewable energy carrier that has recently been ...
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Given the world’s growing population and energy demand, modern methods are developed to contribute to generating alternative energies. They aim to maintain the renewability of the supplied energy and decrease environmental contaminations. Biogas is a renewable energy carrier that has recently been under consideration in Iran. One objective of such plans is to find proper locations for installing and running the existing potentials and infrastructures. In this paper, Tehran, Iran is selected as the study area which is ranked the 1st in population density and proper infrastructures available here are accessible. According to the widespread poultry and cow-breading farms in this province, bovine and aviculture excreta are considered as raw materials in producing biogas. An inference network was established in this research for evaluating the process taking into account the infrastructural parameters, geomorphological constraints, resource availability factors, and limiting parameters such as protected/prohibited areas.In this paper, the fuzzy method was used to standardize the data and the fuzzy-analytical hierarchy process method was employed to weight the locating criteria in the geographical information system. The evaluation outcomes suggested certain zones in southern parts of the province in which the industrial livestock farms become frequently widespread and the suburb areas of smaller cities on the eastern part of the province are the most proper areas for this purpose.
Renewable Energy Resources and Technologies
Parvez Mosharraf; Md. Saroyar Zahan; Dilip Kumar Das; Suman Chowdhury
Abstract
This study offers an effective solution to meet the growing demands of biogas plants for energy. This paper presents a model and simulates the digestion process of biogas production from the organic and food processing waste that contains high moisture. Biogas is produced by bacteria through the bio-degradation ...
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This study offers an effective solution to meet the growing demands of biogas plants for energy. This paper presents a model and simulates the digestion process of biogas production from the organic and food processing waste that contains high moisture. Biogas is produced by bacteria through the bio-degradation of organic material under anaerobic conditions. According to the findings, in case of biogas production, the broiler chicken manure is approximately 88 %. From the analysis, it is observed that the chicken broiler waste is approximately 88 % more efficient than the unsorted waste. In addition, in the case of digestate, the cow manure is approximately 6.25 % more efficient than the garden waste. The present study aims to investigate the performance of different types of wastes regarding biogas production. To this end, different types of waste were considered in data analysis. According to the data analysis, biogas production is highly affected by the type of waste.
Renewable Energy Resources and Technologies
Bahman Heydari; Shahin Rafiee; Elham Abdollahzadeh Sharghi; Seyed Saeid Mohtasebi
Abstract
The aromatic and dark-colored spearmint essential oil wastewater (SEOW) generally contains a large amount of organic matter, including chemical oxygen demand (COD), phenolic compounds, and inorganic contents. In this study, the pollutant removal performance and biogas production rate of an up-flow anaerobic ...
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The aromatic and dark-colored spearmint essential oil wastewater (SEOW) generally contains a large amount of organic matter, including chemical oxygen demand (COD), phenolic compounds, and inorganic contents. In this study, the pollutant removal performance and biogas production rate of an up-flow anaerobic sludge blanket (UASB) reactor used for the treatment of SEOW were investigated. During the 102 days UASB operation at hydraulic retention time of 60 hours, the organic loading rate (OLR) was increased from 0.14 to 2.69 kg COD/m3.d by increasing the influent SEOW concentration. With increasing OLR from 0.14 to 2.69 kg COD/m3.d, the concentrations of COD and phenol in the influent of the UASB reactor increased to 6720±383 mg/L and 383±88 mg/L, respectively. At OLR equal to 2.69 kg COD/m3.d, the steady-state average removal efficiencies of COD and phenol were 72.0±1.4 and 63.1±6.7 %, respectively. The stability of the anaerobic system was confirmed by the average steady-state ratios of the volatile fatty acid/alkalinity and pH in the UASB reactor, which were less than 0.4 and 7.5±0.1, respectively, at different OLRs. The optimum OLR was found to be 2.69 kg COD/m3.d, where 26.9±1.7 L/d production of biogas containing 63.0±5.2 % and 22.4±4.2 % methane and carbon dioxide, respectively, was obtained. Moreover, at OLR equal to 2.69 kg COD/m3.d, the biogas yield and net heating value were 462.2±46.9 L/kg CODremoved and 24.7±5.2 MJ/m3, respectively. The results of the current study reveal the substantial potential of the UASB reactor in terms of pollutant removal performance and biogas production for the treatment of SEOW.
Renewable Energy Resources and Technologies
Alireza Rastikerdar
Abstract
The municipal solid waste in Landfill is transformed into landfill gas during a biochemical conversion process called bio-degradation. Gas release from landfills has potentially different environmental effects; therefore, assessing and forecasting the rate of production and release of gas from landfill ...
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The municipal solid waste in Landfill is transformed into landfill gas during a biochemical conversion process called bio-degradation. Gas release from landfills has potentially different environmental effects; therefore, assessing and forecasting the rate of production and release of gas from landfill sites is important for designing these sites and for the successful exploitation of gases as energy sources. In this study, by using LandGEM model, in the span of 2018-2037, the amount of gases produced from the municipal landfill of Sirjan, Iran has been predicted. According to the results, the largest amount of landfill gas emission will be in 2038, a year following the last year of disposal of the waste to the landfill. The total amount of produced gas, carbon dioxide, methane, and NMOCs will be 1.219E+05, 8.932E+04, 3.255E+04, and 1.399E+03 tons per year in 2038 for Sirjan. In the next step, the LandGEM outputs were imported into OpenLCA software. The health and environmental effects of landfill gas emissions were evaluated by USEtox and traci method, respectively, in this software. According to the USEtox method, the value of total health effects was obtained as 0.032496 CTUh; in addition, by using the traci method, the most environmental burden falls in the impact categories of global warming, photochemical ozone formation, ecotoxicity, acidification, respiratory effects. By making sound and suitable plans as of this 20-year period and implementing tube in this place, greenhouse gas emissions to the atmosphere can probably be prevented. It is also suggested that landfill gases be used to supply energy to the Sirjan recycling plant.
Rozita Asgari; Farida Iraji Asiabadi; Hadi Radnezhad
Abstract
The anaerobic digestion of organic waste for biogas production can be affected by some variables such as temperature; concentration of the biogas feed solution, bacteria populations, and pressure. This study investigated the effects of thermal pretreatment at 50, 75, and 100 ºC on the biogas produced ...
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The anaerobic digestion of organic waste for biogas production can be affected by some variables such as temperature; concentration of the biogas feed solution, bacteria populations, and pressure. This study investigated the effects of thermal pretreatment at 50, 75, and 100 ºC on the biogas produced by simultaneous anaerobic digestion of cow manure, mushroom waste, and wheat straw at thermophilic temperature. Moreover, the effects of a zeolite on reducing the salinity of the wastewater were evaluated. Cow manure, mushroom waste, and wheat straw were mixed to yield a mixture with an optimum carbon to nitrogen ratio of 20-30 and TS of 25-35%. Each thermal pretreatment was prepared in four replicates and placed in a steam bath with a temperature of 55 ºC. The amount of gas produced by each thermal pretreatment was measured every day for 15 days. On day 15, the electrical conductivity of the produced wastewater was measured and the wastewater was exposed to a modified zeolite. The results showed that the greatest level of biogas was produced by thermal pretreatment at 75 ºC, which gave the biogas yield of 0.197 L/gVS after 15 days observation while, the other thermal pretreatments at 50, and 100 ºC gave the biogas yield 0.147, and 0.169 L/gVS, respectively. The highest amount of biogas was achieved on the third day for every three thermal pretreatments. Moreover, the modified zeolite reduced the wastewater salinity by 25%. These results confirmed that thermal pretreatment at 75 ºC is an effective pretreatment for biogas production improvement from the mixture of cow manure, mushroom waste, and wheat straw, and the modified zeolite could be used for salinity reduction of wastewater discharged from the process.
Shoeleh Vahdatpour; Shokoofeh Behzadfar; Leila Siampour; Elahe Veisi; Mehdi Jahangiri
Abstract
Renewable systems influence the process of supplying domestic electricity demands. It will be useful to replace the conventional energy generation system by renewable energy sources since the uncontrolled use of fossil fuels is accompanied by global warming and environmental hazards, in addition ...
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Renewable systems influence the process of supplying domestic electricity demands. It will be useful to replace the conventional energy generation system by renewable energy sources since the uncontrolled use of fossil fuels is accompanied by global warming and environmental hazards, in addition to the danger of their depletion, and because most of the energy derived from these fuels are used in buildings. Economical renewable energy systems have not yet been studied in each climate of Iran. Considering the historical background and the potential biomass of Iran, the potential of using a hybrid solar cell/wind turbine/biomass system for supplying the electricity demands of a residential building in each of the four climate regions of Iran has been studied by using HOMER software in this paper. HOMER software has been determined the most cost-efficient system for each region by using the solar radiation and wind speed data, which are acquired over 20 years. By considering economic issues, results indicate that usage of solar cells is the ideal option for the cold, hot dry and warm humid climates (Total net present cost (NPC) and cost of electricity (COE) are $11639 and 1.808 $/kWh, respectively). Also, usage of systems based on biomass is the best choice for the moderate and humid climates (total NPC and COE are $13211 and 2.052 $/kWh, respectively for Babol and $13075 and 2.031 $/kWh, respectively for Chalous).
Olatunde A. Oyelaran; Yau Y. Tudunwada; James K. Abidoye; Olawale M. Sanusi
Abstract
Biogas production from co-digestion of local brewery waste (BW) and cow dung (CD) was study for value added to this solid waste. The objective of this research was to fine the optimum condition for maximum biogas production and also examined the effectiveness of the biogas residue (liquor from anaerobic ...
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Biogas production from co-digestion of local brewery waste (BW) and cow dung (CD) was study for value added to this solid waste. The objective of this research was to fine the optimum condition for maximum biogas production and also examined the effectiveness of the biogas residue (liquor from anaerobic digestion process) as a nitrogen source for the production of okro. The experiments were performed in a laboratory scale of 1.5 liters plastic bottles were used as digesters operated in batch mode and mesophilic conditions [35°C±0.5]. The feedstock were test in the following ratios CD:BW, 90:10, 80:20. 70:30, 60:40, 50:50, 40:60, 30:70. 20:80 and 10:90. The maximum biogas yield was attained with mixtures in the proportions of 70:30 CD:BW. At these proportions, there was a biogas yield increase as compared to other ratios. The addition of BW increased the biogas yield from 0.40t/lt.day to 0.92lt/lt.day. It was found that CD: BW of 70:30 is the optimum ratio from batch process. The gradual reduction of the VFA concentration clearly indicated the stability of the process. A micro (pot) experiment was conducted to study the comparative effects of biogas residues, and NPK fertilizers on growth and yield using okro as the test crop. Twelve experimental soil filled pot in a complete randomized block design was used comprising of three each for Control T1 (no NPK and no BR), T2 100% NPK fertilizer, T3 50% BR plus 50% NPK fertilizers and T4 biogas residues (BR 100). The parameters studied showed that plant height, root length, number of fruits per plant and fruit weight was affected by the addition of biogas residue. A maximum 20.2% plant height increase over control T1 was observed in T3, 100% NPK has 10% while T4 has 8%. A maximum increase of 28.57% number of fruits was recorded in treatment T2 and T3, while 14.29% increased was recorded in T4 compared with control. The 50% BR applied in combination with 50% NPK (T3) resulted in 25.42% increase in fruit weight over control, T4 has 20.34% and 16.95% was observed in T2. Based on these results, it may be concluded that the application of approximately 50% of biogas residue and 50% inorganic fertilizer improves the production of okro.
Maryam Nosratinia; Ali Asghar Tofigh; Mehrdad Adl
Abstract
The use of renewable energy sources is often suggested to be a good solution for climate change and the dependency to fossil fuel. Biogas utilization is a one of these promising options that can mitigate these problems since biogas is produced by the fermentation of waste, so is rich in methane and has ...
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The use of renewable energy sources is often suggested to be a good solution for climate change and the dependency to fossil fuel. Biogas utilization is a one of these promising options that can mitigate these problems since biogas is produced by the fermentation of waste, so is rich in methane and has the same characteristics as natural gas. Biogas has increasingly been noticed in different countries during last decades, but Iran could not reach its deserved position in comparison with others. The authors believe that absence of a proper management and information system is the main reason for this problem. In this article a decision system is designed in order to reduce the involved risks in making decision and helping in selecting the most appropriate commercialization strategies for utilization of biogas which is achievable from Iran’s livestock and poultry wastes. After a short hint to biogas and its techniques, in this article the main related criteria including biogas site selection and production techniques and utilization options in Iran have been chosen and their weights were calculated according to analytical hierarchy process (AHP). The weight obtained in this research should be considered in future development of Biogas by considering local specifications.
Mahdi Sharifi; Mohammad Haghighi; Farhad Rahmani; Nader Rahemi
Abstract
Utilization of active and stable catalyst could have enormous advantages in industrial application of biogas reforming. In order to achieve this goal, the effects of Cu and Co as promoters were investigated over physical-chemical properties of Ni/Al2O3-ZrO2 catalyst in reforming of biogas. The sequential ...
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Utilization of active and stable catalyst could have enormous advantages in industrial application of biogas reforming. In order to achieve this goal, the effects of Cu and Co as promoters were investigated over physical-chemical properties of Ni/Al2O3-ZrO2 catalyst in reforming of biogas. The sequential impregnation was used for preparation of catalysts. The catalysts were characterized using XRD, FESEM, BET and FTIR analysis. The XRD patterns displayed that the active phases promoters could be effective on nanoparticles dispersion. The FESEM images showed that uniformity of particles size was improved for bimetallic catalysts in comparison with Ni/Al2O3-ZrO2 catalyst but the specific surface areas had no significant change in BET analysis. Higher content of –OH structural groups on surface of Ni-Co/Al2O3-ZrO2 catalyst were proved by FTIR characterization. The performances of catalysts were assessed at atmospheric pressure, feed gas ratio of CO2/CH4= 1, GHSV=24 l/g.h and temperature ranges from 550-850°C. The results revealed Ni-Co/Al2O3-ZrO2 catalysts had the best activity. Because of optimized operating condition and application of ZrO2 as a promoter, the activities of all catalysts remained stable at 850°C for 24 h.
