Degree of Biomass Conversion in the Integrated Production of Bioethanol and Biogas

Abstract

The integrated production of bioethanol and biogas makes it possible to optimise the production of carriers from renewable raw materials. The installation analysed in this experimental paper was a hybrid system, in which waste from the production of bioethanol was used in a biogas plant with a capacity of 1 MWe. The main objective of this study was to determine the energy potential of biomass used for the production of bioethanol and biogas. Based on the results obtained, the conversion rate of the biomass—maize, in this case—into bioethanol was determined as the efficiency of the process of bioethanol production. A biomass conversion study was conducted for 12 months, during which both maize grains and stillage were sampled once per quarter (QU-I, QU-II, QU-III, QU-IV; QU—quarter) for testing. Between 342 L (QU-II) and 370 L (QU-I) of ethanol was obtained from the organic matter subjected to alcoholic fermentation. The mass that did not undergo conversion to bioethanol ranged from 269.04 kg to 309.50 kg, which represented 32.07% to 36.95% of the organic matter that was subjected to the process of bioethanol production. On that basis, it was concluded that only two-thirds of the organic matter was converted into bioethanol. The remaining part—post-production waste in the form of stillage—became a valuable raw material for the production of biogas, containing one-third of the biodegradable fraction. Under laboratory conditions, between 30.5 m3 (QU-I) and 35.6 m3 (QU-II) of biogas per 1 Mg of FM (FM—fresh matter) was obtained, while under operating conditions, between 29.2 m3 (QU-I) and 33.2 m3 (QU-II) of biogas was acquired from 1 Mg of FM. The Biochemical Methane Potential Correction Coefficient (BMPCC), which was calculated based on the authors’ formula, ranged from 3.2% to 7.4% in the analysed biogas installation.

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

“…Biogas energy, being affordable and accessible, is one of the most promising alternative energy sources, alongside wind and solar energy [2]. Unlike wind and solar energy, biogas energy does not require specialized infrastructure, making it a viable option for countries and regions with diverse topography [3,4]. Biogas, as an energy source independent of weather conditions, is crucial for the stability and security of energy supplies in the future.…”

Biogas Plants: Fundamentals, Operation and Prospects

“…As the planet's traditional energy sources are finite and rapidly declining, the need to explore alternative and sustainable sources of energy has become pressing [1]. Biogas energy, being affordable and accessible, is one of the most promising alternative energy sources, alongside wind and solar energy [2,3]. Unlike wind and solar energy, biogas energy does not require specialized infrastructure, making it a viable option for countries and regions with diverse topography [4].…”

Influence of Modification of the Plasticizing System on the Extrusion-Cooking Process and Selected Physicochemical Properties of Rapeseed and Buckwheat Straws

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