Fundamentals, Operation and Global Prospects for the Development of Biogas Plants—A Review

Abstract

As the global demand for renewable energy continues to rise, biogas production has emerged as a promising solution for sustainable energy generation. This review article presents the advantages of biogas technologies (mainly agricultural, based on waste of animal and plant origin) and extensively discusses the main principles of biogas production in the anaerobic digestion (AD). In this respect, the main parameters of the process, which require monitoring and decisive for its efficiency are described, therefore: temperature, pH value, retention time and organic loading rate (OLR). The principles of substrate selection are also discussed and the necessity and advantages of the use of organic waste according to the model of a circular economy and the concept of sustainable development, are indicated. It is emphasized that according to the new European regulations, the crops classified as food cannot be considered energy crops. The part on biogas production is summarised with an explanation of the necessity to treat and purify biogas. Biogas purification is important from the point of view of the efficiency of its conversion into electricity. A special place in this paper is devoted to the design, construction, functioning and operation of biogas plants, based on both scientific and practical aspects. In conclusion of this chapter, the economic aspects and profitability of operating biogas plants are discussed. Cost and benefit analyses are the major tool used for the systematic evaluation of the financial costs and potential benefits associated with the operation of biogas plants. The important fact is that the return on investment can be achieved within a few years, provided the activities are well-planned and executed. In addition to the fundamental issues of the operation of biogas plants, this article presents the global situation regarding the development of biogas plants, discussing in detail the specific needs and limitations on different continents. It is a interesting and extensive part of this article. The global agricultural biogas market is at very different levels of development. Most such installations are located in Asia and Europe. China has the highest number of biogas plants, with more than 100,000 biogas plants, followed by Germany with over 10,000 plants. In addition to the 100,000 biogas plants, China also has a large number of household biogas units, which gives a total of approx. 40 million operating units. The article concludes with a discussion of opportunities and barriers to the development of biogas plants, pointing to: financial issues, access to feedstock, political regulations, public awareness and the geopolitical situation. The most frequently cited reasons for investment failure include economic problems, lack of professional knowledge.

Animal Manure as an Alternative Bioenergy Resource in Rural Sub-Saharan Africa: Present Insights, Challenges, and Prospects for Future Advancements

“…The use of animal manure for energy generation, and in particular as feedstock for anaerobic digestor technology, has received extensive coverage in both the research and review literature globally as well as in the sub-Saharan Africa (SSA) context. The vast majority of this research, however, is focussed on anaerobic digestor-process improvement [17], in particular on feedstock choices for increased biogas output [18][19][20], bioreactor design and diagnosis of bioreactor failures [21], impacts of private-public partnerships on biogas technology development [22], and socio-economic barriers to technology adoption [23,24]. In so doing, lab-scale successes and achievements are often misconstrued for on-the-ground implementation success whereas, in practicality, there is a disconnect between research and implementation [25].…”

The Use of Hydrodynamic Cavitation to Improve the Anaerobic Digestion of Waste from Dairy Cattle Farming—From Laboratory Tests to Large-Scale Agricultural Biogas Plants

“…Around 19,000 biogas plants are in operation in the European Union (EU) [3]. Germany is the leader in the implementation of this technology with over 10,000 plants, followed by Italy with over 2000 biogas plants and France with around 1.6 thousand facilities [4]. The creation of new AD systems is currently very dynamic.…”

Effect of Biochar on Anaerobic Co-Digestion of Untreated Sewage Sludge with Municipal Organic Waste under Mesophilic Conditions

“…In addition, China has domestic biogas generation programs, so the number of plants is approximately 40 million. Meanwhile, Germany has more than 10,000 biogas plants [7].…”