Study of regime parameters of the fermenter in the production of biogas from animal liquid waste materials

Abstract

The focus of the present study is a small biogas power plant for anaerobic fermentation of several types of animal waste raw materials used for biogas production. The impact of some of the characteristics of substances such as composition, temperature, humidity, and pH of the mixture in the bioreactor has been considered. The above is vital for optimizing the fermentation process, and also to improve the biogas production process. The plant is located in Northeastern Bulgaria and the raw liquid manure is supplied by several neighboring small farms. The annual quantities of raw waste are as follows: cow manure - 1252 t / a; chicken manure - 427 t / a and pig manure - 639 t / a. The manure is collected in a preliminary tank and then pumped to the bioreactor. The fermenter itself is a hermetically sealed and thermally insulated tank where constant temperature is maintained. It is equipped with a stirring system, which helps the mixing and homogenization of the substrate. The tests were performed during three charges of the installation. The fermentation takes approximately 23 up to 25 days. The experiments were performed during the summer and autumn seasons when the ambient air temperature varies from 28 to 45 °C. The biogas can be used as an energy carried as the obtained organic fertilizer is suitable for agriculture purposes.

Study of the efficiency of the joint operation of a cogeneration steam turbine with a heat pump installation

“…The inputs that are entered for the steam turbine are the initial pressure pо and temperature tо of the steam, the steam consumption Dо and the relative internal efficiency ηoi . It is mandatory that the unregulated steam outlets of the steam turbine are connected to equipment (low pressure, high pressure preheaters, deaerator) to which steam is supplied, according to the simulation modeling scheme [4][5][6][7][8][9][10][11][12].…”

Pathways for the Valorization of Animal and Human Waste to Biofuels, Sustainable Materials and Value-Added Chemicals

“…The collected manure will then be blended with the reactor's agitator so that they become homogenized for the microorganisms to decompose the manure into methane (CH4), carbon dioxide (CO2), and organic fertilizer in an anaerobic environment. The fermentation process normally lasts up to 23 days, either for thermophilic-type (33-34 o C) or mesophilic-type (53-55 o C) conditions [162].…”

Pathways for the Valorization of Animal and Human Waste to Biofuels, Sustainable Materials, and Value-Added Chemicals

“…The collected manure will then be blended with the reactor's agitator, so that they become homogenized for the microorganisms to decompose the manure into methane (CH 4 ), carbon dioxide (CO 2 ), and organic fertilizer in an anaerobic environment. The fermentation process normally lasts up to 23 days, either for thermophilic-type (33-34 • C) or mesophilic-type (53-55 • C) conditions [120].…”