REVIEW OF BIOGAS TECHNOLOGIES

Keywords: Biogas, construction material, plug flow, fixed dome and floating drum digester.

This review is a summary of different aspects of the design and operation of biogas digesters. Three types of digesters were reviewed, that is, the plug flow, floating drum and the fixed dome digester. Biogas is one of the products formed during the anaerobic digestion process. Anaerobic digestion is dependent on several factors such as the pH value, feeding material, temperature, pressure, organic loading rate, retention time and the Carbon-to- Nitrogen (C/N) ratio. The shape of the digester and the material for construction are also considered important during design stage.

Emerald Insight, World Journal of Engineering, 2020

A novel cost-effective bio-digester was explored to convert biological waste into useful clean energy. The bioreactor was aimed to anaerobically digest locally sourced cow dung and chicken droppings. The design consideration is a batch horizontal 267 L digester made from cast iron with centrally positioned four-impeller shaft to enhance mixing. The system operated with a retention time of 63 days and a substrate (cow dung and poultry waste) ratio of 1:2 and water substrate ratio of 1:0.5 in the gasholder system. The purification, compression and performance evaluation of the generated biogas were also conducted. The total volume of gas produced for each substrate compositions designed over 14 days ranges between 49.34 and 52.91 mL/day. The optimal value of 52.45 ml using cow dung and poultry waste (w/w) 20:80 was obtained. The average ambient temperatures during the study were within the mesophilic range of 20-40°C. The pH values were stable and always in the optimal range of 6.5-8.0. The reductions in moisture content, ash content, total solids and volatile solids were from 80.50-0.20 per cent, 39.60-14 per cent, 18.50-5.90 per cent and 11.60-4.90 per cent, respectively. The developed digester is cost-effective and would help minimize solid waste disposal. The estimated methane contents of the gas from cow dung and chicken waste after scrubbing were found to be 71.95 per cent and could be harnessed in solving the energy crisis in the developing nations.

Renewable & Sustainable Energy Reviews, 2014

The authors reviewed the global methods of biogas production, enrichment, compression and storage for energy generation and highlighted its potential application in meeting energy needs in developing countries, with emphasis on Nigeria. Biogas is becoming an increasingly important source of clean energy for rural and urban areas in developing countries, as can be seen by the increased construction of biodigesters. Biogas digester technology has been domesticated in Nigeria and a number of pilot biogas plants have been built with majority (over 75%) of operational Nigerian manure digesters on piggery, cattle farms or abattoirs. A trend is now seen among academic institutions in Nigeria in the design and construction of biogas digesters, for instance, the Usman Danfodio University Biogas Plant, the Obafemi Awolowo University plant, the University of Ibadan prototype (with a patent), Non-Governmental Organisations (NGOs) and Private sector involvement, which shows increasing interest and availability of biogas technology. Biogas is a renewable fuel that is 60-70% methane and can be used to power household appliances and generate electricity using appropriate technologies. These technologies include Biogas digesters which are being used to collect farm animal waste and convert it to biogas through anaerobic bacterial processes. The biogas generated is enriched through a process of scrubbing to obtain at least 95% purity. The current research focus of the authors towards improving biogas yield, enrichment, compression and storage for use in Nigeria is discussed. The current findings indicate that there are economic advantages for the utilisation of biogas in developing countries like Nigeria.

Biogas technolog y can be play a vital role in supplying of energy demand while utilizing solid waste as a raw material for the gas generation. This research was carried out to find out possible avenues to produce Biogas from Agricultural waste such as paddy straw and market garbage. The objectives of the study were to (1) analyze the chemical composition of market garbage and paddy straw, (2) find the composition of market garbage and (3) assess the gas production pattern in biomethantion of market garbage and paddy straw. Two Sri Lankan batch type digesters were used with a volume of 5m 3 and total weight of the market garbage and paddy straw filled in to the digester were 3580 kg and 871 kg respectively. Cow dung and Urea were added to the paddy straw digester as inoculum s and to balance the C: N ratio in to 30:1. Carbon, Nitrogen, Potassium and Phosphorous in raw material were analyzed. Daily gas generation and pressure indicate by the manometer in each digester were measured. ...

Biogas, a clean and renewable form of energy could very well substitute (especially in the rural sector) for conventional sources of energy (fossil fuels, oil, etc.) which are causing ecological-environmental problems and at the same time depleting at a faster rate. In this work, different feed stocks such as water hyacinth and paddy chaff (Paddy waste it contain from paddy husk and un matured Rice) with boiled condition were used as feed stock for producing biogas. This paper reviews the important parameters like temperature pressure, C/N ratio, total solid concentration and hydro retention time (HRT) which could be used to enhance the gas production rate from solid substrates under mesophilic condition with temperature ranging from 28°C to 36°C. A closed type portable digester (batch type process) was used. The biogas produced from water hyacinth was finally ignited.

Zenodo (CERN European Organization for Nuclear Research), 2022

In countries like India food waste accounts for more than 50% of the Municipal solid waste collected. Food waste has a lot of potential to be used as a raw material because of its enrichment in organic properties. This review paper presents a study on the basic principles of anaerobic digestion and the reactions which let it occur. Here we have observed all those factors on which the efficiency and production of biogas depends such as pH, Temperature, C/N Ratio, Retention Time. We also have discussed the parameters so that some changes in the digester can be done to increase the efficiency.

Results in Chemistry, 2024

Biogas is obtained from the breakdown of biomass by microorganisms and bacteria in the absence of oxygen. Biogas is considered a renewable source of energy, similar to solar energy and wind energy. Biogas can be produced from biomass or bio-waste; thus, it is environmentally friendly. Biogas is obtained in a suspended monoxide decomposition process by anaerobic bacteria or in a fermentation process of decomposable materials such as agricultural manure, sewage, municipal waste, green waste (gardens and parks), plant material and agricultural products. Biogas is a renewable natural energy source that leaves effective effects on nature and industries. This gas is produced from the decomposition of organic materials, including animal manure, food waste and sewage. Fertilizers and waste produce biogas through anaerobic digestion (ie without the presence of oxygen). Biogas is a mixture of gases generated by decaying biodegradable material without the presence of oxygen. Its main contents are 50–70 % of methane (CH4) by volume, 30–50 % of carbon dioxide (CO2), and traces of other gases, like hydrogen sulfide (H2S) and water vapor (H2O). CO2, H2S, and water vapor content in biogas may affect the performance and life of the energy conversion devices; consequently, their removal before end-use is essential for improving the quality of biogas. This combination is an ideal option for making renewable energy. The most important advantages of biogas (production of energy, reduction of the amount of discarded waste, reduction of pathogens, conversion of waste containing organic matter into high quality fertilizer, protection of vegetation, soil, water, increasing productivity in the field of livestock and agriculture) and It is also one of the disadvantages of biogas (incomplete and small technologies, containing impurities, the effect of temperature on biogas production, unsuitable for urban and dense areas, not affordable). For economical use of biogas, the fermentation process can be carried out under controlled conditions in a relatively simple device called a digestion reservoir. This review summarizes the current state-of-the-art and presents future perspectives related to the anaerobic digestion process for biogas production. Moreover, a historical retrospective of biogas sector from the early years of its development till its recent advancements give an outlook of the opportunities that are opening up for process optimization.

IRJET, 2022

Climate change demands clean water and sustainable energy. Advances in wastewater treatment may allow for the recovery of valuable resources like biogas and fertilizers. Long-term sewage treatment is harder. This study looks on getting biogas from STPs. The technology's applicability for various applications is examined by comparing its performance to those applications. These systems' technical and environmental performance is also evaluated. The next step is to develop a framework for monitoring sustainability and include essential indicators. This is a STP in Greater Noida, Uttar Pradesh. Annually, 1.417*106 m3 biogas may be produced, greatly lowering CO2 emissions. Combining wastewater and sludge improves biogas recovery. STPs may help achieve the SDGs (SDGs). The multilateral and cross-cutting nature of resource recovery benefits is demonstrated by their linkages with SDGs. New water treatment methods and prospect.

Anaerobic Digestion Technology for Biogas Production: Current Situation in Nigeria (A Review), 2023

In view of the nation's vast agricultural resources, crop residues, animal manure, municipal waste, and wastewater sludge may be transformed into renewable energy, potentially a source of revenue. Biogas production offers cleaner, sustainable solutions across the nation. The compass of supportive policy and regulation emerges, guiding investment toward transformative shores. Various "Waste-to-Energy" academic researches and pilot projects illuminate paths to energy generation, waste management and sustainability with the prospects of a viable bioeconomy. The application of anaerobic digestion technology contributes to a greener and more sustainable energy future. In Nigeria, biogas production holds multifaceted benefits which include energy sustainability waste management, and climate change mitigation. By harnessing organic waste, energy source diversification reduces reliance on fossil fuels. Biogas mitigates environmental pollution, converts waste to value, which is key to climate goals. Sustaining biogas production requires incentives, research, expertise, public awareness, and infrastructure. Collaboration and strategic partnerships will likely accelerate Nigeria's biogas production potential. In conclusion, this review underscores the immense potential of biogas production in Nigeria. It seeks to enliven the discussion for fostering efficient management of the abundant organic resources, supportive policies, public engagement, technological advancements, and partnerships that can bring about a wider implementation of biogas production projects across Nigeria towards a greener and sustainable energy future.