In order to promote the utilization level of new energy resources for local and efficient consumption,this paper introduces the biogas(BG)fermentation technology into the integrated energy system(IES).This initiative ...In order to promote the utilization level of new energy resources for local and efficient consumption,this paper introduces the biogas(BG)fermentation technology into the integrated energy system(IES).This initiative is to study the collaborative and optimal scheduling of IES with wind power(WP),photovoltaic(PV),and BG,while integrating carbon capture system(CCS)and power-to-gas(P2G)system.Firstly,the framework of collaborative operation of IES for BG-CCS-P2G is constructed.Secondly,the flexible scheduling resources of the source and load sides are fully exploited,and the collaborative operation mode of CCS-P2G is proposed to establish a model of IES with WP,PV,and BG multi-energy flow coupling.Then,with the objective of minimizing the intra-day operating cost and the constraints of system energy balance and equipment operating limits,the IES withWP,PV,and BG collaborative optimal scheduling model is established.Finally,taking into account the uncertainty of the output of WP and PV generation,the proposed optimal scheduling model is solved by CPLEX,and its validity is verified by setting several scenarios.The results show that the proposed collaborative operation mode and optimal scheduling model can realize the efficient,low-carbon,and economic operation of the IES with WP,PV,and BG and significantly enhance the utilization of new energy for local consumption.展开更多
The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National ...The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence.展开更多
The overall objective of this work is to evaluate the energy potential of biogas inputs(chicken manure and pig poop)with a view to their value.The research determined the physicochemical composition,the amount of biog...The overall objective of this work is to evaluate the energy potential of biogas inputs(chicken manure and pig poop)with a view to their value.The research determined the physicochemical composition,the amount of biogas produced per day and the average.For hen dung,humidity(28.47%),DM(dry matter)(71.53%),OM(organic matter)(67%),density(270.77 kg/m^(3)),carbon content(39.7%),nitrogen content(2.55%)and C/N ratio(15.23)and pig pork,moisture(47.98%),DM(45.6%),OM(23.55%),mass volumic(693.12 kg/m^(3)),carbon(38.88%),nitrogen(1.82%)and C/N(11.26).These results compared to those of the literature revealed a very good coincidence.Two experiments on the methanation of these inputs were carried out,the anaerobic digestion lasted 24 days,in a temperature range of 24 to 30℃(mesophilic range).It was obtained for:hen dung 0.02526 m^(3) and pig poach 0.00841 m^(3) and on average the daily specific production of biogas of different substrates is:pork dung(0.00407 m^(3)/day)and the hen dung(0.00108 m^(3)/d)at an average temperature of 24℃.展开更多
To solve the problems in restoring sedimentary facies and predicting reservoirs in loose gas-bearing sediment,based on seismic sedimentologic analysis of the first 9-component S-wave 3D seismic dataset of China,a four...To solve the problems in restoring sedimentary facies and predicting reservoirs in loose gas-bearing sediment,based on seismic sedimentologic analysis of the first 9-component S-wave 3D seismic dataset of China,a fourth-order isochronous stratigraphic framework was set up and then sedimentary facies and reservoirs in the Pleistocene Qigequan Formation in Taidong area of Qaidam Basin were studied by seismic geomorphology and seismic lithology.The study method and thought are as following.Firstly,techniques of phase rotation,frequency decomposition and fusion,and stratal slicing were applied to the 9-component S-wave seismic data to restore sedimentary facies of major marker beds based on sedimentary models reflected by satellite images.Then,techniques of seismic attribute extraction,principal component analysis,and random fitting were applied to calculate the reservoir thickness and physical parameters of a key sandbody,and the results are satisfactory and confirmed by blind testing wells.Study results reveal that the dominant sedimentary facies in the Qigequan Formation within the study area are delta front and shallow lake.The RGB fused slices indicate that there are two cycles with three sets of underwater distributary channel systems in one period.Among them,sandstones in the distributary channels of middle-low Qigequan Formation are thick and broad with superior physical properties,which are favorable reservoirs.The reservoir permeability is also affected by diagenesis.Distributary channel sandstone reservoirs extend further to the west of Sebei-1 gas field,which provides a basis to expand exploration to the western peripheral area.展开更多
Globalization has led to a rapid rise in energy consumption,making climate change one of the world's most pressing issues.As wastewater treatment plants(WWTPs)contribute to climate change by emitting greenhouse ga...Globalization has led to a rapid rise in energy consumption,making climate change one of the world's most pressing issues.As wastewater treatment plants(WWTPs)contribute to climate change by emitting greenhouse gases(GHGs),this study estimated the total GHG emissions of WWTPs by classifying them as either direct or indirect carbon emissions.The effectiveness of the use of solar photovoltaic systems and biogas produced by WWTPs in increasing energy recovery and reducing GHG emissions was investigated.This study demonstrated that the use of an up-flow anaerobic sludge blanket(UASB)reactor with a biogas flow of 9120.77 m3/d and an activated sludge processing system(ASPS)reactor with a biogas flow of 14004 m^(3)/d,in addition to the energy production from the UASB reactor(6421.8 MW⸱h per year)and the ASPS reactor(9860.0 MW⸱h per year),yielded a reduction of 3316.85 and 5092.69 t of CO_(2)equivalent per year,respectively.Furthermore,the co-design of wastewater processes could be utilized to optimize biogas energy recovery.Moreover,the use of solar photovoltaic systems reduced GHG emissions from WWTPs.This is important to the transition to renewable energy because it resulted in a 10%-40%reduction in carbon emissions from WWTPs.Integrating renewable energy sources,biogas,and solar energy could provide up to 88%of the annual energy requirements of WWTPs.Recommendations are provided for further research considering the limited availability of integrated resources for studying the simultaneous utilization of photovoltaic and biogas systems.展开更多
Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only real...Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas field.To improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this study.The thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame structure.The flame size was reduced by increasing the CO_(2) concentration and the flames became lighter blue.The flame temperature also decreased with increase in CO_(2) concentration.Flame stability was reduced by increasing the CO_(2) concentration.However,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the stability.Accordingly,the IPPS mode of combustion should be suitable for the combustion and stabilization of biogas.This should support the design of highly stabilized biogas turbulent flames independent of CO_(2) concentration.The data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant.展开更多
This present research work focuses on the valorization of pig droppings for production of biogas in mono digestion and co-digestion with proportions of cow dung from the urban commune of N’Zérékoré. It...This present research work focuses on the valorization of pig droppings for production of biogas in mono digestion and co-digestion with proportions of cow dung from the urban commune of N’Zérékoré. It was carried out in December 2020 in the Physics laboratory of the University of N’Zérékoré. The anaerobic digestion process took 25 days in an almost constant ambient temperature of 25˚C. Five digesters were loaded on 12/06/2020, two of which with 1 kg of pig dung and 1 kg of cow dung both in mono-digestion. The 3 other digesters in co-digestion with different proportions of pig manure and cow dung. The substrate in each digester is diluted in 2 liters of water, with a proportion of (1/2). The main results obtained are: 1) the evolution of the temperature and pH during digestion process, 2) the average biogas productions 0.61 liters for (D1);1.20 liter for (D2);1.65 liter for (D3);1.51 liter for (D4) and 1.31 liter for (D5). The cumulative amounts of biogas are respectively: D1 (7.95 liters), D2 (15.60 liters), D3 (21.50 liters), D4 (19.65 liters) and D5 (17.05 liters). The total cumulative production is 81.75 liters at the end of the process. The originality of this research work is that the proposed model examines the relation between the daily biogas production and the variation of temperature, pH and pressure. The combustibility test showed the biogas produced during the first week was no combustible (contains less than 50% methane). Combustion started from the biogas produced from the 15th day and it is from the 20th day that a significant amount of stable yellow/blue flame was observed. The results of this study show the combination of pig manure and cow dung presents advantages for optimal biogas production.展开更多
[Objective] The aim was to improve the biogas production rate,and improve the use ratio of rice straws to the furthest.[Method] Single-factor method was adopted to analyze the influence of inoculated amount,total soli...[Objective] The aim was to improve the biogas production rate,and improve the use ratio of rice straws to the furthest.[Method] Single-factor method was adopted to analyze the influence of inoculated amount,total solid content and carbon-nitrogen ratio on biogas production in biogas station of Nanjing University of Technology.[Result] It was found that the most optimum condition was：inoculated amount of 34%,total solid content of 6%,and carbon-nitrogen ratio of 25：1.According to the experimental verification,the total biogas yield in experimental group increased by 27.6% over the control group.[Conclusion] The research provided the reference of the further industrialization production of biogas using straw.展开更多
The general objective of this present work is to refine biogas in order to use it in an engine to produce electricity. The specific objective is focused on the availability and creation of energy, environmental protec...The general objective of this present work is to refine biogas in order to use it in an engine to produce electricity. The specific objective is focused on the availability and creation of energy, environmental protection, and the provision of biofertilizers to name a few. We worked on industrial applications and data for two years. The calculation methods and the most important parameters measured and observed during the work with various types of equations and monitoring, such as the search for the useful volume of the digester, the retention time, the organic load rate, the daily production of biogas, and the technological yield were made. The biogas produced was refined following the standards and purification procedure and the presence of H2S brought back to a ppm lower than 200. To better characterize our biogas, a weekly, monthly and annual monitoring was done. The aim of this monitoring was to understand the production curve and bring technological elements of positive change by working on the pH, the temperature, the ratio and inhibitors. Thus, at the beginning, at 25˚C and 1 atm, the 6 gas molecules had a volume of 146.61 liters, so for 1 g of COD consumed, there was 0.7636 L of gas with 50% CH4 and 50% CO2. We therefore sought to make this result higher with a biogas rate of 60% CH4 and 40% CO2. It is observed that the values can vary by ±10% (sometimes more) depending on the implementation conditions.展开更多
[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to...[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to provide basis for scientific application of biogas slurry.[Methods]The fields with different years of continuous application of biogas slurry in Dingnan Rare Earth Tailings Ecological Restoration Demonstration Park were selected as the research object,and the differences in soil physical and chemical properties and microbial community structure after application of biogas slurry for different years(0,3 and 5 years)were studied.[Results]The bulk density of soil with continuous application of biogas slurry showed a downward trend,while the maximum water holding capacity,capillary water holding capacity,porosity,aeration,pH,organic matter,nitrogen,phosphorus and potassium,alkali-hydrolyzable nitrogen and available phosphorus showed an upward trend.Moreover,the effects achieved by application for 5 years were better than those by application for 3 years.Continuous application of biogas slurry could significantly improve the activity of soil urease,acid phosphatase,sucrase and cellulase,and it effects increased with the application year increasing.Continuous application of biogas slurry could significantly improve the abundance of dominant bacteria in soil,and with the increase of application years,the abundances of dominant bacteria also increased.[Conclusions]Continuous application of biogas slurry effectively improved soil physical and chemical properties and soil fertility in rare earth tailings areas where Pennisetum×sinese was planted to restore rare earth tailings.This study provides a theoretical support for establishing key ecological restoration technoiques.展开更多
An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of cli...An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of climate conditions on the performance of solar collectors with different lengths of parabolic trough solar collector (dx) and mass flow rate of heat transfer fluid (m). In addition, this study has evaluated the amount of H2 produced by biogas dry reforming (GH2), the amount of power generated by SOFC (PSOFC) and the maximum number of possible households (N) whose electricity demand could be met by the energy system proposed, considering the performance of solar collector with the different dx and m. As a result, the optimum dx was found to be 4 m. This study revealed that the temperature of heat transfer fluid (Tfb) decreased with the increase in m. Tfb in March, April and May was higher than that in other months, while Tfb from June to December was the lowest. GH2, PSOFC and N in March, April and May were higher than those in other months, irrespective of m. The optimum m was 0.030 kg/s.展开更多
In order to explore the effects of landfill composed of biogas residue and slurry on the improvement of soil nutrients and cherry fruit yield, three treatments： control （no landfill）, landfilling with biogas residu...In order to explore the effects of landfill composed of biogas residue and slurry on the improvement of soil nutrients and cherry fruit yield, three treatments： control （no landfill）, landfilling with biogas residue and water （BR）, landfilling with biogas residue and slurry （BS） were conducted in a cherry orchard. The results showed that compared with the control, soil water content around the landfills with a radius of 60 cm within 30 d was increased in BR and BS treatments. The poment- age of short shoots and the total number of shoots of cherry trees were also signif- icantly increased by BR and BS treatments; the cherry fruit yield per tree and the single-fruit weight in BS treatment were increased by 21.76% and 28.89%, respec- tively. In addition, BS treatment obviously improved the contents of soil organic matter, soil available nitrogen, s0il available phosphorus, soil available potassium and other nutrients. The positive effects of BR treatment on the improvement of soil nutrients and cherry fruit yield were lower than those of BS treatment, indicating that the combined use of biogas residue and biogas slurry as landfill can improve the soil water and fertilizer status in orchards, and thus can be promoted in the cultivation of fruit trees.展开更多
[Objective] The paper aimed to study highly efficient utilization of biogas slurry and the effect of highly efficient biogas slurry on vegetables,so as to provide basis for wide and effective application of biogas slu...[Objective] The paper aimed to study highly efficient utilization of biogas slurry and the effect of highly efficient biogas slurry on vegetables,so as to provide basis for wide and effective application of biogas slurry.[Method] Using secondary aerobic fermentation technology,a small amount of humic acid was added to biogas slurry to enhance the biological activity of biogas slurry.Through greenhouse experiment,the effect of highly efficient nutrient solution of biogas slurry on yield and quality of green pepper,tomato and cucumber was studied.[Result] Compared with control and traditional application of biogas slurry,application of highly efficient nutrient solution of biogas slurry increased the yield of green pepper,tomato and cucumber,and the increase extents were 12.4%,47.4%,19.9% and 2.7%,15.9%,9.1%,respectively.Compared with traditional application of biogas slurry,application of highly efficient nutrient solution of biogas slurry significantly increased Vc content of green pepper and cucumber with the increase extent of 16.8% and 43.8%,respectively.[Conclusion] Application of highly efficient nutrient solution of biogas slurry can effectively promote the yield of green pepper,tomato and cucumber and change the qualities of vegetables,and significantly enhance the biological activity of biogas slurry.展开更多
[Objective] This study was to provide scientific basis for the security application of biogas slurry in agriculture through the analysis on the security risk of nu- trients and heavy metals of biogas slurry in agricul...[Objective] This study was to provide scientific basis for the security application of biogas slurry in agriculture through the analysis on the security risk of nu- trients and heavy metals of biogas slurry in agricultural application. [Method] The components of the slurry produced by the anaerobic digestion of straws and manures were systematically analyzed. Different types of biogas slurry with different concentrations were used to conduct the germination test. [Result] The types and proportions of raw materials, and alkali pretreatment affected the compositions and nature of the biogas slurry. Alkali pretreatment could reduce the contents of heavy metals and improved the contents of nitrogen, phosphorous, organic matter and available components. The contents of heavy metals in the biogas slurry were as follows： Cd of 8.76 μg/kg, Cr of 52μg/kg, Pb of 210 μg/kg, Hg of 0.512 μg/kg, As of 140μg/kg, and the contents of Cu and Zn were the highest among the heavy metals, respectively, 279 and 680 μg/kg. All the contents were under the limit standards of the urban wastes for agricultural use. The germination tests of the seeds verified that the slurry with the concentration of lower than 5% could accelerate the germination, while the salt stress could inhibit the growth of seedlings in the slurry. [Conclusion] When the dung are uses as the raw materials for fermentation, appropriate control should be conducted on the feeding proportion or the heavy metals should be pre-removed; when the slurry is used as the liquid fertilizer to apply in the farmland, the dilution or desalting treatment should be conducted at first.展开更多
In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet...In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet sorghum and Chinese cabbage were planted in purple soils, the quantities of digested biogas slurry were of 57, 157.5, and 34.5 t/hm2, respectively, while the quantities of digested biogas slurry were 70.5, 157.5 and 40.5 t/hm2 in yellow soils. Besides, the digested biogas slurries reached 36 and 27 t/hm2 as per flood irrigation and sprinkling irrigation when Chinese cabbages were planted in yellow soils. The research indicated crop variety, soil type, and irrigation method all have effects on farmland digestion of biogas slurry.展开更多
[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user...[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user＇s need and function demand were studied.Sub-system function was divided.By using SuperMap IS.NET,C# and SQL Server 2005 as the database and WebGIS frame,the system spatial and attribute database were designed so as to realize the WebGIS software of biogas project in Beijing.[Result] The system provided application platform for the distribution of biogas project information.User can realize the submission and inquiry the feedback of biogas project information based on system application right etc,so as to visually,fully and precisely inquiry project data.Based on the comprehensive analysis of data,the current state of biogas project and change trend were studied and decided.[Conclusion] The system provided convenience and services to relevant departments＇ planning and management of biogas project.展开更多
S<span>everal challenges are associated </span></span><span style="font-family:"">with</span><span style="font-family:""> the development, adoption and...S<span>everal challenges are associated </span></span><span style="font-family:"">with</span><span style="font-family:""> the development, adoption and de</span><span style="font-family:"">ployment of biogas digesters in developing countries. Amongst these challenges is a comprehensive and systematic procedure for the design of digesters suitable for rural communities. This paper proposes the Flexible Biogas Digester System (FBDS) as a viable option for rural communities in developing countries and provide</span><span style="font-family:"">s</span><span style="font-family:""> a detailed step-by-step procedure for it</span><span style="font-family:"">s</span><span style="font-family:""> design. The biogas production process is a function of the digester operating factors which may be grouped into physical, process and performance parameters. The physical design parameters include</span><span style="font-family:""> </span><span style="font-family:"">the digester volume, the volume of the biogas storage tank, and the volume of the installation pit. The process parameters include total solid content of the slurry (TS), organic loading rate (OLR), digester operating temperatures, pH of the slurry inside the digester. The performance parameters include</span><span style="font-family:""> </span><span style="font-family:"">biogas production rate, biogas productivity and biogas quality. The Net Present Value and the Levelised Cost of Energy are presented for simple economic evaluation of the FBDS.展开更多
Through indoor culture experiments, the effects of continuous irrigation of biogas slurry on the forms and biological availability of Pb in soil of a tea garden were studied. The results show that continuous irrigatio...Through indoor culture experiments, the effects of continuous irrigation of biogas slurry on the forms and biological availability of Pb in soil of a tea garden were studied. The results show that continuous irrigation of biogas slurry could change the forms of Pb in the soil, and exchangeable Pb, Pb bonded to iron and manganese oxides, and Pb bonded to carbonates transformed to Pb bonded to or- ganic matter and residual Pb in the soil. Among various forms of Pb in the soil, the content of residual Pb was the highest in the soil irrigated with biogas slurry contin- uously in various treatments, accounting for 54.56%, 60.00% and 60.70% in the treatments T1, T2 and T3 respectively. Compared with the CK, the application of bio- gas slurry could decrease the biological activity and biological availability of Pb in the soil obviously, and the reduction of the biological activity was 21.26%-22.83%. In a word, the application of biogas slurry in soil of the tea garden could inhibit the biological activity and biological availability of Pb.展开更多
In order to implement National Sustainable Development of Agriculture 2015-2030 and supply-side reform of agriculture, and seek the way to replace chemical fertilizer by livestock and poultry manure, the animal breedi...In order to implement National Sustainable Development of Agriculture 2015-2030 and supply-side reform of agriculture, and seek the way to replace chemical fertilizer by livestock and poultry manure, the animal breeding scale and the demand space for biogas project were analyzed according to the changes in farm scale and farm quantity, the present situation of livestock breeding, the biogas technical pattern and present project quantity in Chengdu. Furthermore, based on the cultivated land area in Chengdu, a principle that ＂land decides production, pro- duction decides fertilizer, and fertilizer decides livestock＂ was proposed, and a pro- gram for the livestock quantity and biogas projects in Chengdu in ＂The 13th Five- Year＂ was suggested. Suggestions were also made for government to modify the allowance standards for biogas project construction.展开更多
In order to provide help for the accurate application of biogas slurry in the field, the application of biogas slurry and control technology of hydrogen sulfide in biogas slurry were reviewed. Results of recent resear...In order to provide help for the accurate application of biogas slurry in the field, the application of biogas slurry and control technology of hydrogen sulfide in biogas slurry were reviewed. Results of recent researches suggested that source control and end-treatment were the two measures to remove hydrogen sulfide in biogas slurry, including physical method, chemical method and biological method. Some conventional deodorizing methods were introduced and compared.展开更多
文摘In order to promote the utilization level of new energy resources for local and efficient consumption,this paper introduces the biogas(BG)fermentation technology into the integrated energy system(IES).This initiative is to study the collaborative and optimal scheduling of IES with wind power(WP),photovoltaic(PV),and BG,while integrating carbon capture system(CCS)and power-to-gas(P2G)system.Firstly,the framework of collaborative operation of IES for BG-CCS-P2G is constructed.Secondly,the flexible scheduling resources of the source and load sides are fully exploited,and the collaborative operation mode of CCS-P2G is proposed to establish a model of IES with WP,PV,and BG multi-energy flow coupling.Then,with the objective of minimizing the intra-day operating cost and the constraints of system energy balance and equipment operating limits,the IES withWP,PV,and BG collaborative optimal scheduling model is established.Finally,taking into account the uncertainty of the output of WP and PV generation,the proposed optimal scheduling model is solved by CPLEX,and its validity is verified by setting several scenarios.The results show that the proposed collaborative operation mode and optimal scheduling model can realize the efficient,low-carbon,and economic operation of the IES with WP,PV,and BG and significantly enhance the utilization of new energy for local consumption.
文摘The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence.
文摘The overall objective of this work is to evaluate the energy potential of biogas inputs(chicken manure and pig poop)with a view to their value.The research determined the physicochemical composition,the amount of biogas produced per day and the average.For hen dung,humidity(28.47%),DM(dry matter)(71.53%),OM(organic matter)(67%),density(270.77 kg/m^(3)),carbon content(39.7%),nitrogen content(2.55%)and C/N ratio(15.23)and pig pork,moisture(47.98%),DM(45.6%),OM(23.55%),mass volumic(693.12 kg/m^(3)),carbon(38.88%),nitrogen(1.82%)and C/N(11.26).These results compared to those of the literature revealed a very good coincidence.Two experiments on the methanation of these inputs were carried out,the anaerobic digestion lasted 24 days,in a temperature range of 24 to 30℃(mesophilic range).It was obtained for:hen dung 0.02526 m^(3) and pig poach 0.00841 m^(3) and on average the daily specific production of biogas of different substrates is:pork dung(0.00407 m^(3)/day)and the hen dung(0.00108 m^(3)/d)at an average temperature of 24℃.
基金Supported by the CNPC Science and Technology Projects(2022-N/G-47808,2023-N/G-67014)RIPED International Cooperation Project(19HTY5000008).
文摘To solve the problems in restoring sedimentary facies and predicting reservoirs in loose gas-bearing sediment,based on seismic sedimentologic analysis of the first 9-component S-wave 3D seismic dataset of China,a fourth-order isochronous stratigraphic framework was set up and then sedimentary facies and reservoirs in the Pleistocene Qigequan Formation in Taidong area of Qaidam Basin were studied by seismic geomorphology and seismic lithology.The study method and thought are as following.Firstly,techniques of phase rotation,frequency decomposition and fusion,and stratal slicing were applied to the 9-component S-wave seismic data to restore sedimentary facies of major marker beds based on sedimentary models reflected by satellite images.Then,techniques of seismic attribute extraction,principal component analysis,and random fitting were applied to calculate the reservoir thickness and physical parameters of a key sandbody,and the results are satisfactory and confirmed by blind testing wells.Study results reveal that the dominant sedimentary facies in the Qigequan Formation within the study area are delta front and shallow lake.The RGB fused slices indicate that there are two cycles with three sets of underwater distributary channel systems in one period.Among them,sandstones in the distributary channels of middle-low Qigequan Formation are thick and broad with superior physical properties,which are favorable reservoirs.The reservoir permeability is also affected by diagenesis.Distributary channel sandstone reservoirs extend further to the west of Sebei-1 gas field,which provides a basis to expand exploration to the western peripheral area.
文摘Globalization has led to a rapid rise in energy consumption,making climate change one of the world's most pressing issues.As wastewater treatment plants(WWTPs)contribute to climate change by emitting greenhouse gases(GHGs),this study estimated the total GHG emissions of WWTPs by classifying them as either direct or indirect carbon emissions.The effectiveness of the use of solar photovoltaic systems and biogas produced by WWTPs in increasing energy recovery and reducing GHG emissions was investigated.This study demonstrated that the use of an up-flow anaerobic sludge blanket(UASB)reactor with a biogas flow of 9120.77 m3/d and an activated sludge processing system(ASPS)reactor with a biogas flow of 14004 m^(3)/d,in addition to the energy production from the UASB reactor(6421.8 MW⸱h per year)and the ASPS reactor(9860.0 MW⸱h per year),yielded a reduction of 3316.85 and 5092.69 t of CO_(2)equivalent per year,respectively.Furthermore,the co-design of wastewater processes could be utilized to optimize biogas energy recovery.Moreover,the use of solar photovoltaic systems reduced GHG emissions from WWTPs.This is important to the transition to renewable energy because it resulted in a 10%-40%reduction in carbon emissions from WWTPs.Integrating renewable energy sources,biogas,and solar energy could provide up to 88%of the annual energy requirements of WWTPs.Recommendations are provided for further research considering the limited availability of integrated resources for studying the simultaneous utilization of photovoltaic and biogas systems.
基金funded by the American University in Cairo research grants(Project number SSE-MENG-M.M.-FY18-FY19-FY20-RG(1-18)–2017-Nov-11-17-52-02).
文摘Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas field.To improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this study.The thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame structure.The flame size was reduced by increasing the CO_(2) concentration and the flames became lighter blue.The flame temperature also decreased with increase in CO_(2) concentration.Flame stability was reduced by increasing the CO_(2) concentration.However,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the stability.Accordingly,the IPPS mode of combustion should be suitable for the combustion and stabilization of biogas.This should support the design of highly stabilized biogas turbulent flames independent of CO_(2) concentration.The data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant.
文摘This present research work focuses on the valorization of pig droppings for production of biogas in mono digestion and co-digestion with proportions of cow dung from the urban commune of N’Zérékoré. It was carried out in December 2020 in the Physics laboratory of the University of N’Zérékoré. The anaerobic digestion process took 25 days in an almost constant ambient temperature of 25˚C. Five digesters were loaded on 12/06/2020, two of which with 1 kg of pig dung and 1 kg of cow dung both in mono-digestion. The 3 other digesters in co-digestion with different proportions of pig manure and cow dung. The substrate in each digester is diluted in 2 liters of water, with a proportion of (1/2). The main results obtained are: 1) the evolution of the temperature and pH during digestion process, 2) the average biogas productions 0.61 liters for (D1);1.20 liter for (D2);1.65 liter for (D3);1.51 liter for (D4) and 1.31 liter for (D5). The cumulative amounts of biogas are respectively: D1 (7.95 liters), D2 (15.60 liters), D3 (21.50 liters), D4 (19.65 liters) and D5 (17.05 liters). The total cumulative production is 81.75 liters at the end of the process. The originality of this research work is that the proposed model examines the relation between the daily biogas production and the variation of temperature, pH and pressure. The combustibility test showed the biogas produced during the first week was no combustible (contains less than 50% methane). Combustion started from the biogas produced from the 15th day and it is from the 20th day that a significant amount of stable yellow/blue flame was observed. The results of this study show the combination of pig manure and cow dung presents advantages for optimal biogas production.
基金Suppoted by the National Natural Science Foundation of China(21046004 )the National Key Technology R & D Program(2011BAD15B02)+1 种基金the National Program of Key Basic Research Project (2009CB724700)the Provincial Key Technology R & DProgram (BE20)~~
文摘[Objective] The aim was to improve the biogas production rate,and improve the use ratio of rice straws to the furthest.[Method] Single-factor method was adopted to analyze the influence of inoculated amount,total solid content and carbon-nitrogen ratio on biogas production in biogas station of Nanjing University of Technology.[Result] It was found that the most optimum condition was：inoculated amount of 34%,total solid content of 6%,and carbon-nitrogen ratio of 25：1.According to the experimental verification,the total biogas yield in experimental group increased by 27.6% over the control group.[Conclusion] The research provided the reference of the further industrialization production of biogas using straw.
文摘The general objective of this present work is to refine biogas in order to use it in an engine to produce electricity. The specific objective is focused on the availability and creation of energy, environmental protection, and the provision of biofertilizers to name a few. We worked on industrial applications and data for two years. The calculation methods and the most important parameters measured and observed during the work with various types of equations and monitoring, such as the search for the useful volume of the digester, the retention time, the organic load rate, the daily production of biogas, and the technological yield were made. The biogas produced was refined following the standards and purification procedure and the presence of H2S brought back to a ppm lower than 200. To better characterize our biogas, a weekly, monthly and annual monitoring was done. The aim of this monitoring was to understand the production curve and bring technological elements of positive change by working on the pH, the temperature, the ratio and inhibitors. Thus, at the beginning, at 25˚C and 1 atm, the 6 gas molecules had a volume of 146.61 liters, so for 1 g of COD consumed, there was 0.7636 L of gas with 50% CH4 and 50% CO2. We therefore sought to make this result higher with a biogas rate of 60% CH4 and 40% CO2. It is observed that the values can vary by ±10% (sometimes more) depending on the implementation conditions.
文摘[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to provide basis for scientific application of biogas slurry.[Methods]The fields with different years of continuous application of biogas slurry in Dingnan Rare Earth Tailings Ecological Restoration Demonstration Park were selected as the research object,and the differences in soil physical and chemical properties and microbial community structure after application of biogas slurry for different years(0,3 and 5 years)were studied.[Results]The bulk density of soil with continuous application of biogas slurry showed a downward trend,while the maximum water holding capacity,capillary water holding capacity,porosity,aeration,pH,organic matter,nitrogen,phosphorus and potassium,alkali-hydrolyzable nitrogen and available phosphorus showed an upward trend.Moreover,the effects achieved by application for 5 years were better than those by application for 3 years.Continuous application of biogas slurry could significantly improve the activity of soil urease,acid phosphatase,sucrase and cellulase,and it effects increased with the application year increasing.Continuous application of biogas slurry could significantly improve the abundance of dominant bacteria in soil,and with the increase of application years,the abundances of dominant bacteria also increased.[Conclusions]Continuous application of biogas slurry effectively improved soil physical and chemical properties and soil fertility in rare earth tailings areas where Pennisetum×sinese was planted to restore rare earth tailings.This study provides a theoretical support for establishing key ecological restoration technoiques.
文摘An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of climate conditions on the performance of solar collectors with different lengths of parabolic trough solar collector (dx) and mass flow rate of heat transfer fluid (m). In addition, this study has evaluated the amount of H2 produced by biogas dry reforming (GH2), the amount of power generated by SOFC (PSOFC) and the maximum number of possible households (N) whose electricity demand could be met by the energy system proposed, considering the performance of solar collector with the different dx and m. As a result, the optimum dx was found to be 4 m. This study revealed that the temperature of heat transfer fluid (Tfb) decreased with the increase in m. Tfb in March, April and May was higher than that in other months, while Tfb from June to December was the lowest. GH2, PSOFC and N in March, April and May were higher than those in other months, irrespective of m. The optimum m was 0.030 kg/s.
基金Supported by Shandong Provincial Key Research and Development Project(2015GSF117005)Major Innovation Project for Applied Technology of Shandong Province(2017)~~
文摘In order to explore the effects of landfill composed of biogas residue and slurry on the improvement of soil nutrients and cherry fruit yield, three treatments： control （no landfill）, landfilling with biogas residue and water （BR）, landfilling with biogas residue and slurry （BS） were conducted in a cherry orchard. The results showed that compared with the control, soil water content around the landfills with a radius of 60 cm within 30 d was increased in BR and BS treatments. The poment- age of short shoots and the total number of shoots of cherry trees were also signif- icantly increased by BR and BS treatments; the cherry fruit yield per tree and the single-fruit weight in BS treatment were increased by 21.76% and 28.89%, respec- tively. In addition, BS treatment obviously improved the contents of soil organic matter, soil available nitrogen, s0il available phosphorus, soil available potassium and other nutrients. The positive effects of BR treatment on the improvement of soil nutrients and cherry fruit yield were lower than those of BS treatment, indicating that the combined use of biogas residue and biogas slurry as landfill can improve the soil water and fertilizer status in orchards, and thus can be promoted in the cultivation of fruit trees.
基金Supported by"Eleventh Five-Year"National Technology Support Program(2008BADC4B17)~~
文摘[Objective] The paper aimed to study highly efficient utilization of biogas slurry and the effect of highly efficient biogas slurry on vegetables,so as to provide basis for wide and effective application of biogas slurry.[Method] Using secondary aerobic fermentation technology,a small amount of humic acid was added to biogas slurry to enhance the biological activity of biogas slurry.Through greenhouse experiment,the effect of highly efficient nutrient solution of biogas slurry on yield and quality of green pepper,tomato and cucumber was studied.[Result] Compared with control and traditional application of biogas slurry,application of highly efficient nutrient solution of biogas slurry increased the yield of green pepper,tomato and cucumber,and the increase extents were 12.4%,47.4%,19.9% and 2.7%,15.9%,9.1%,respectively.Compared with traditional application of biogas slurry,application of highly efficient nutrient solution of biogas slurry significantly increased Vc content of green pepper and cucumber with the increase extent of 16.8% and 43.8%,respectively.[Conclusion] Application of highly efficient nutrient solution of biogas slurry can effectively promote the yield of green pepper,tomato and cucumber and change the qualities of vegetables,and significantly enhance the biological activity of biogas slurry.
基金Supported by the National Key Technology R&D Program of China during the 11th Five-year Plan Period (2008BAC4B13)the Fundamental Research Fund for the Central Universities (ZZ1101)~~
文摘[Objective] This study was to provide scientific basis for the security application of biogas slurry in agriculture through the analysis on the security risk of nu- trients and heavy metals of biogas slurry in agricultural application. [Method] The components of the slurry produced by the anaerobic digestion of straws and manures were systematically analyzed. Different types of biogas slurry with different concentrations were used to conduct the germination test. [Result] The types and proportions of raw materials, and alkali pretreatment affected the compositions and nature of the biogas slurry. Alkali pretreatment could reduce the contents of heavy metals and improved the contents of nitrogen, phosphorous, organic matter and available components. The contents of heavy metals in the biogas slurry were as follows： Cd of 8.76 μg/kg, Cr of 52μg/kg, Pb of 210 μg/kg, Hg of 0.512 μg/kg, As of 140μg/kg, and the contents of Cu and Zn were the highest among the heavy metals, respectively, 279 and 680 μg/kg. All the contents were under the limit standards of the urban wastes for agricultural use. The germination tests of the seeds verified that the slurry with the concentration of lower than 5% could accelerate the germination, while the salt stress could inhibit the growth of seedlings in the slurry. [Conclusion] When the dung are uses as the raw materials for fermentation, appropriate control should be conducted on the feeding proportion or the heavy metals should be pre-removed; when the slurry is used as the liquid fertilizer to apply in the farmland, the dilution or desalting treatment should be conducted at first.
基金Supported by International Science&Technology Cooperation Program of China(2013DFA61260)Sub-project of National Science and Technology Planning in Rural Areas during the 12th Five-year Plan(2011BAD36B01)~~
文摘In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet sorghum and Chinese cabbage were planted in purple soils, the quantities of digested biogas slurry were of 57, 157.5, and 34.5 t/hm2, respectively, while the quantities of digested biogas slurry were 70.5, 157.5 and 40.5 t/hm2 in yellow soils. Besides, the digested biogas slurries reached 36 and 27 t/hm2 as per flood irrigation and sprinkling irrigation when Chinese cabbages were planted in yellow soils. The research indicated crop variety, soil type, and irrigation method all have effects on farmland digestion of biogas slurry.
基金Supported by Countryside Energy Comprehensive Construction Pro-ject of Science,Technology and Education Branch of AgriculturalDepartment [AFD2009J54]~~
文摘[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user＇s need and function demand were studied.Sub-system function was divided.By using SuperMap IS.NET,C# and SQL Server 2005 as the database and WebGIS frame,the system spatial and attribute database were designed so as to realize the WebGIS software of biogas project in Beijing.[Result] The system provided application platform for the distribution of biogas project information.User can realize the submission and inquiry the feedback of biogas project information based on system application right etc,so as to visually,fully and precisely inquiry project data.Based on the comprehensive analysis of data,the current state of biogas project and change trend were studied and decided.[Conclusion] The system provided convenience and services to relevant departments＇ planning and management of biogas project.
文摘S<span>everal challenges are associated </span></span><span style="font-family:"">with</span><span style="font-family:""> the development, adoption and de</span><span style="font-family:"">ployment of biogas digesters in developing countries. Amongst these challenges is a comprehensive and systematic procedure for the design of digesters suitable for rural communities. This paper proposes the Flexible Biogas Digester System (FBDS) as a viable option for rural communities in developing countries and provide</span><span style="font-family:"">s</span><span style="font-family:""> a detailed step-by-step procedure for it</span><span style="font-family:"">s</span><span style="font-family:""> design. The biogas production process is a function of the digester operating factors which may be grouped into physical, process and performance parameters. The physical design parameters include</span><span style="font-family:""> </span><span style="font-family:"">the digester volume, the volume of the biogas storage tank, and the volume of the installation pit. The process parameters include total solid content of the slurry (TS), organic loading rate (OLR), digester operating temperatures, pH of the slurry inside the digester. The performance parameters include</span><span style="font-family:""> </span><span style="font-family:"">biogas production rate, biogas productivity and biogas quality. The Net Present Value and the Levelised Cost of Energy are presented for simple economic evaluation of the FBDS.
基金Supported by Scientific Research Project of Education Department of Zhejiang Province(Y201328325)Public Welfare Project of Lishui City(2012JYZB47)+1 种基金Project for Highlevel Talents of Lishui City(2014RC04)Project for the Transformation of Agricultural Scientific and Technological Achievements(2012NZH0205)~~
文摘Through indoor culture experiments, the effects of continuous irrigation of biogas slurry on the forms and biological availability of Pb in soil of a tea garden were studied. The results show that continuous irrigation of biogas slurry could change the forms of Pb in the soil, and exchangeable Pb, Pb bonded to iron and manganese oxides, and Pb bonded to carbonates transformed to Pb bonded to or- ganic matter and residual Pb in the soil. Among various forms of Pb in the soil, the content of residual Pb was the highest in the soil irrigated with biogas slurry contin- uously in various treatments, accounting for 54.56%, 60.00% and 60.70% in the treatments T1, T2 and T3 respectively. Compared with the CK, the application of bio- gas slurry could decrease the biological activity and biological availability of Pb in the soil obviously, and the reduction of the biological activity was 21.26%-22.83%. In a word, the application of biogas slurry in soil of the tea garden could inhibit the biological activity and biological availability of Pb.
文摘In order to implement National Sustainable Development of Agriculture 2015-2030 and supply-side reform of agriculture, and seek the way to replace chemical fertilizer by livestock and poultry manure, the animal breeding scale and the demand space for biogas project were analyzed according to the changes in farm scale and farm quantity, the present situation of livestock breeding, the biogas technical pattern and present project quantity in Chengdu. Furthermore, based on the cultivated land area in Chengdu, a principle that ＂land decides production, pro- duction decides fertilizer, and fertilizer decides livestock＂ was proposed, and a pro- gram for the livestock quantity and biogas projects in Chengdu in ＂The 13th Five- Year＂ was suggested. Suggestions were also made for government to modify the allowance standards for biogas project construction.
基金Supported by the National Key Technology R&D Program of China(2012BAD14B00)~~
文摘In order to provide help for the accurate application of biogas slurry in the field, the application of biogas slurry and control technology of hydrogen sulfide in biogas slurry were reviewed. Results of recent researches suggested that source control and end-treatment were the two measures to remove hydrogen sulfide in biogas slurry, including physical method, chemical method and biological method. Some conventional deodorizing methods were introduced and compared.
