Fixed Dome Biogas Plants Research Articles

Harnessing Biogas Resources for Production of Methane Gas

Nigeria faces a significant challenge in providing reliable and affordable cooking fuel, particularly in rural areas and educational institutions. Reliance on traditional biomass fuels like firewood and charcoal contributes to deforestation, environmental degradation, and respiratory health problems. Additionally, access to Liquefied Petroleum Gas (LPG) can be limited and expensive. This project presents the design and construction of a 100-liter fixed-dome biogas plant for cooking applications. The plant was constructed using readily available materials, focusing on affordability and ease of assembly. The project aimed to harness organic waste and convert it into a sustainable and renewable fuel source. Following construction, the plant underwent a testing phase, successfully generating 5kg of biogas within 10 days. This highlights the plant’s potential for providing clean and sustainable cooking fuel in resource-constrained settings. This research contributes to ongoing efforts to address Nigeria’s fuel challenges by offering a localized, sustainable, and potentially cost-effective solution.

Enhancement of Biogas Production from Fixed Dome Biogas Plant through Recycling of Digested Slurry

Enhancement of Biogas Production from Fixed Dome Biogas Plant through Recycling of Digested Slurry

Design of a Co-Digestion Biogas Plant to Curb Deforestation-Case Study of Phalombe Secondary School in Malawi

Biogas technology is one of the renewable technologies that use biodegradable waste such as human waste (HW), agricultural waste, animal and food waste. Over 90% of the population in Malawi is heavily reliant on firewood as their primary source of energy for cooking. This results in deforestation, pollution of the environment, and great monetary expenditure to buy firewood, more especially by boarding schools. A co-digestion biogas plant that uses human, animal, agriculture, and canteen food waste has been designed. This study design was based on the use of HW and canteen food wastes (CFW) as the substrate for the biodigester to produce methane (CH4) gas that could be used for cooking and lighting at Phalombe Secondary School in Malawi to replace firewood. With a school population of 757 people, design calculations/stimations were performed to find out the amount of HW and CFW required per day. A field survey at the school was carried out to appreciate the problem the school is facing so that a solution could be found. Based on factors such as energy demand at the school, availability of feedstock, size of the digester, biogas yield, life span of the biodigester, and availability of construction materials, the type of biogas plant suitable for this purpose has been selected and designed. A computer-aided design (Auto CAD) software was used for the drawing. These design parameters were arrived at through a baseline survey, observation methods, and literature reviews. Through a questionnaire, a detailed energy demand analysis was carried out from whose results a fixed dome biogas plant of digester size 62 m3, gasometer of size 19 m3, and digestate collection tank size of 61 m3 has been designed. The design came up with an amount of HW and CFW of 286 and 60 kg per day respectively making total organic raw materials of 346 kg per day. The macromolecular composition of the HW, CFW, and mixture of HW and CFW in terms of dry matter (DM) was 11%, 45% and 56% of carbohydrate, 3%, 15%, and 18% of protein, 15%, 40%, and 30% lipids, and 15%, 0%, and 15% of ash respectively. The substrate showed a high degradability of 90%. The simulation analysis showed that HW produced 185 m3 per kg of biogas which represented 64% and 35.9% CH4 and carbon dioxide (CO2), CFW produced 58.9 m3 per kg that represented 61.1% and 38.4% of CH4 ad CO2, and mixture produced 265 m3 per kg contained 59% and 41% of CH4 and CO2 in 40 days respectively. A cost estimate of the design has been carried out to appreciate the economic viability of the biogas technology and is estimated at the US$5277. The cost of constructing a biogas plant at the school is less than what the school is spending currently on firewood and electricity, a recommendation has been made to adopt the technology to reduce the financial burden the school is facing.

Methane enrichment of biogas produced from floral waste: A potential energy source for rural India

ABSTRACTBiogas has emerged as a clean and cheap energy source with additional advantages like waste disposal solution and an alternative for fossil fuels. Raw biogas contains methane between 50% and 70% and carbon dioxide between 30% and 50%, along with traces of hydrogen sulfide and moisture. Presence of contaminants like carbon dioxide and hydrogen sulfide in biogas restricts its applications in India for cooking and lighting purpose or at the place of its generation. Thus, for making biogas as a transportable fuel or for other widespread applications, removal of contaminants from biogas becomes a necessary step. Small-scale biogas plants seldom use purification and scrubbing systems because of cost considerations and inadequate knowledge of purification techniques. The present experimental work uses floral waste with alkaline pretreatment as an input substrate, for biogas production in Deenbandhu-type fixed-dome biogas plant, used in rural parts of India. The experimental investigation focuses on methane enrichment of biogas by removal of contaminants like carbon dioxide, hydrogen sulfide, and moisture from biogas, using chemical absorption technique. Packed column reactors arranged in series facilitate biogas purification and scrubbing process at around atmospheric pressure and temperature. The materials used for filling the purification columns include steel wool, silica gel, and different aqueous alkaline solutions of sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2), sodium carbonate (Na2CO3), and monoethanolamine (MEA). A pedal-operated compressor pressurizes raw biogas and forces it through a series of packed chemical absorption columns for the removal of contaminants. Content analysis of purified biogas and raw biogas contents has been done using gas chromatography. The analysis of purified biogas samples 1 and 2 shows methane enrichment up to 96.91% and 94.16% and the carbon dioxide removal efficiency of 99.85% and 98.86% while hydrogen sulfide removal efficiency of 87.5% and 62.5% for samples 1 and 2, respectively. Purification results for biogas show the potential of the purified gas for applications like running stationery engines or use as a vehicular fuel. The purification and scrubbing technique used in the present work uses low-cost commercial chemicals, and the purification columns comprise 4-in-diameter polyvinyl chloride pipes. Use of the technique on a large scale by common people can further raise the potential of biogas as an energy source with a high heating value for widespread applications. Using floral waste from temples as an input substrate provides an energy-efficient solution for soil and water pollution, arising due to the disposal of the waste into the soil or nearby water resources like a river.

Design and performance analysis of floating dome type portable biogas plant for domestic use in Pakistan

Agriculture continues to play a vital role in Pakistan’s economy; it contributes 21% toward the GDP and involves 45% of labor of Pakistan. Livestock is the largest depositor to the agriculture. Therefore biomass can be used in Pakistan as one of the renewable energy source which can be utilized to create electrical power and to provide heating. Fermentation process of biomass releases biogas which acts as a energy source. Two main type of biogas plants are used worldwide which are fixed dome biogas plants and floating dome biogas plant. Livestock owners in remote areas of Pakistan move themselves according to the climate conditions suitable for their livestock. The issue with these plants is that livestock owners cannot move the biogas plant at another spot easily. Hence, there is a need to develop a portable biogas plant which can be conveniently reinstalled at new place effortlessly. This paper described the designing and development of portable biogas plant. The performance of the developed plant and biogas productivity is verified by experiment tests. The developed product is favorable for its long life, light in weight and it has ability to produce enough methane gas to suffice the domestic requirements.

SNV supported domestic biogas programmes in Asia and Africa

Abstract SNV 1 is supporting the implementation of market-based domestic biogas programmes in different countries in Asia and Africa with a view to establish a commercially viable biogas sector. Till the end of 2009, some 300,000 fixed-dome biogas plants of sizes ranging from 4 m3 to 15 m3 have been installed. These plants produce about 600,000 m3 of biogas each day which supplements more than 3000 tonnes of fuel wood. Benefits of biogas plants have positive impacts on basic livelihood indicators as well as rural economic development. The key to success has been the multi-stakeholder sector development approach in optimising organisational and institutional capacities within national contexts. This paper highlights approaches, achievements, lessons learnt and other relevant aspects of domestic biogas programmes in developing countries.

Design and Performance Evaluation of a Commercial size Fixed Dome Biogas Plant

A community size fixed dome cattle dung feed biogas plant of 25 m3 capacity, based on solid-state fermentation, was designed and constructed with brick masonry without using RCC. The shape of the designed plant was of capsule structure. The diameter of lower spherical segment of digester was 4.95 m with the height of the middle cylindrical section as 1.98 m and the depth of bottom spherical segment as 0.98 m. Two cement pipes, diameter 600 mm, were attached to facilitate the feeding of charge. Feeding was carried out with fresh cattle dung having moisture content of 16 per cent. The gas yield varied between 19.56 and 22.45 m3/day with methane content varying between

Greenhouse Gases Emission from Energy Production in Conventional Biogas Plants in India

This article deals with the evaluation of the atmospheric CH4 and CO2 emission from the widely accepted conventional biogas plants operating in India. CH4 and CO2 are the two major constituents of biogas and also the two important greenhouse gases causing the present global warming. Average CH4 and CO2 emission per plant from the floating gasholder model biogas plants ranged between 73 ± 8.92 and 742 ± 81.53 g d−1 and 159 ± 17.31 and 1476 ± 152.63 g d−1, respectively. Emissions from the fixed dome biogas plants ranged between 93 ± 20.63 and 288 ± 46.53 g d−1 CH4 and 196 ± 40.90 and 598 ± 93.70 g d−1 CO2. The current contribution of greenhouse gases from the installed biogas plants in India toward the annual atmospheric CH4 and CO2 budget is estimated to be approximately 0.143 and 0.306 Tg, respectively.

05/02151 Methane emission from fixed dome biogas plants in hilly and plain regions of northern India

05/02151 Methane emission from fixed dome biogas plants in hilly and plain regions of northern India

Methane emission from fixed dome biogas plants in hilly and plain regions of northern India

Methane emissions from the slurry displacement chambers of different fixed dome type biogas plants (Capacity 2 m 3) installed in hilly and plain regions of northern India were quantitatively estimated. The slurry temperature in the biogas plants in the hilly areas of Himachal Pradesh at an altitude of 1300 m above mean sea level remains below the lower mesophilic range (16–25 °C) during most part of the year. Difference in the ambient temperature under the two climatic conditions of Hills and plain regions affects the CH 4 flux. Methane fluxes from the plants ranged between 7 and 120 g m −2 d −1. In northern plain, temperature remains warm (21–33 °C) throughout the year except during winter (December to January) when there is a steep fall. Seasonal emission of CH 4 ranged between 10 and 178 g m −2 d −1. The annual average methane emission from the biogas plants in plain areas was 83.1 g m −2 d −1 as compared to 43.1 g m −2 d −1in the hilly areas. Annual contribution per plant to the global methane budget from a fixed dome biogas plant (Cap 2 m 3) in plain region of northern India was 53.2 kg as compared 22.3 kg in hilly area.

The TERI fixed dome biogas plant model—A case study of development through user interaction and field research

SYNOPSIS Several variations of the fixed dome biogas plants were constructed and monitored for performance in an attempt to improve the reliability and functionality of the plant and to optimise the plant design. Plants were constructed on selected user sites so that user response was obtained along with performance data. The data collected thus represented accurately the field conditions and was used for continuous improvements in design. A total of 46 plants were constructed in different locations with as many as eight different design variations and about 32 plant-years of gas production data was accumulated. The process of evolution from one prototype to another was, however, not smooth and organised due to the very nature of field based development.

Performance Evaluation of Janata and Deenbandhu Biogas Plants

Performance of the Janata and Deenbandhu fixed dome biogas plants for anaerobic digestion of dairy manure was evaluated under the conditions of a hilly region. In contrast to Janata, the Deenbandhu biogas plant was found to be not only cheaper on the basis of cost / m3 rated capacity of the plant, but it also produced more gas per unit of manure fed and per unit of digester volume in addition to maintaining a consistent rate of gas production during subsequent years from initial charging. The higher production of gas by 28.5% and 12.5% per kg of manure fed and 49.5% and 28.9% per m3 of digester volume was observed from this plant for highest 24°C and lowest 14°C digester temperatures of the plants for the months of July and December respectively.

A static scum-breaking net for fixed-dome biogas plants

A static scum-breaking device in the form of a nylon net has been incorporated in a fixed-dome biogas plant to control scum formation and to provide a limited amount of stirring. The performance of the plant has been monitored for one year and compared to that of similar conventional plants. An annual performance ratio is defined so as to account for variable retention times, and has been found to be equal to unity for plants of the same design. The performance ratio for the plant with the scum-breaking net was found to be about 12% higher than that of conventional plants.

A heat-transfer analysis of fixed-dome biogas plants

A steady-state heat transfer analysis has been carried out for fixed-dome biogas plants (Chinese type). The analysis takes into account heat losses from the surface of the slurry inside the digester as well as the heat losses to the surrounding earth. Results indicate that methods such as hot-charging or greenhouse heating can increase the digester temperature by a maximum of 5–7°C, and that burning part of the gas to heat the digester does not result in a net energy-gain. The heating requirements are proportionally much lower for higher-size plants. The heating requirements are reduced by insulating the dome, but no further significant reduction is achieved by adding insulation to the side walls.

Solar assisted biogas plants IV: Optimum area for blackening and double glazing over a fixed-dome biogas plant

The paper presents the economic analysis of a fixed-dome biogas plant of rated capacity 8 m3, above which a part of the ground is blackened and doubly glazed in the cold climate of Srinagar. Blackening and glazing of the ground cannot alone maintain the slurry temperature at 35°C, which is the optimum temperature in the mesophilic range for the anaerobic digestion of cattle dung, and so a part of the biogas must be burnt. The electrical simulation experiments have been performed to determine the loss or gain of heat from the underground biodigestor to the ambient atmosphere through the ground if a part of the ground above is blackened and double glazed. Economic analysis of the system shows that the optimum area to be blackened and glazed would have a radius 1.5 times that of the biodigestor.

Solar assisted biogas plants IV A: Experimental validation of a numerical model for slurry temperature in a glazed fixed-dome biogas plant

The paper presents a comparison between the theoretical and experimental temperatures of digester slurry in a glazed fixed-dome biogas plants. The agreement is within ±2.6°C except for an instance of 4.2°C in the month of April 1988.

Solar assisted biogas plants III: Energy balance of fixed dome biogas plants and enhancement of production in winters

This paper presents a thermal model of a fixed dome biogas plant, with or without hot charging and having the ground surface above the plant, blackened and glazed. The rate of energy transfer, between the ground and the plant has been determined by electrical simulation experiments, using a small scale model of the plant (made of copper), suspended in copper sulphate solution. For hot charging a shallow solar pond, built on the ground has been considered. The monthly variation of the slurry temperature, corresponding to 1, 4, 8, 15 and 30 m3 plants have been evaluated for Madras, New Delhi and Srinagar, which correspond to typical hot, composite and cold climates; the following cases have been considered: 1 Bare plant, without hot charging and blackening/glazing of the ground, above the plant. 2 Plant, charged with hot slurry from a shallow solar pond. 3 Plant, with ground above blackened and glazed. 4 Plant, with ground above blackened and double glazed and also provision for heating the slurry by burning a part of the produced biogas. It is seen that blackening and single glazing of the ground above the plant is able to maintain the slurry temperature between 28 and 35°C throughout the year in composite climate such as Delhi; in cold climates even double glazing alone is not enough for that purpose. Hot charging from a shallow solar pond alone is not sufficient to maintain satisfactory slurry temperatures in winters of Delhi and of course Srinagar. In hot climates the slurry temperature is sufficiently high, except for a couple of months, when either hot charging from a shallow solar pond or blackening/glazing of the ground above is sufficient to have the slurry temperature in the desirable range. In cold climates such as Srinagar, the desired slurry temperatures can be maintained if a part of the gas produced is burnt for heating the slurry, in addition to blackening and double glazing of the ground above the dome. Theoretical predictions of slurry temperatures have been compared with the field data recorded for an 8 m3 digester at the Energy Complex, Masoodpur, Delhi; the agreement is satisfactory.