Energy parameters and feedstock management in farm-scale biogas plants: survey in the North-East of Italy

Abstract. Bibliometric analysis of publications allows to quantify researchers' interests in this specific topic. This method enables the identification of key authors, who are publishing in this area. It is necessary to define research trends, which have developed in this specific field. It enables to determinate the main research topics, discoveries and correlations in the global knowledge network. The purpose of this work was to identify the trends and research topics in engineering for rural development. The modified method of bibliometric analysis was used, bibliometric analysis of the key word frequency of occurrence and the linkages between the key words. The analysis was performed using bibliometirc post-conference materials of the International Scientific Conference Engineering for Rural Development in Jelgava in the years 2012-2017 downloaded from Web of Science database. The data have been processed and cleaned, then analysed in VOSviewer. This program is used for creating and graphic visualisation of bibliometric maps. VOSviewer utilized the method of "visualization of similarities" VOS. In this work the program was used to create maps of terms in the version of "thermic maps". The main research topics have been presented in the form of associated networks. The last stage was detailed topical analysis and classification into groups according to selected criteria. The provided research enabled an identification of lines of the research. The main research topics in all research period were: energy qualities of plant materials, alternative fuel (biomass, biodiesel, biogas), renewable energy sources, modelling, optimisation and stimulation of processes, mechanisation of plant production and many more. This analysis can be used as a literature review in the selected knowledge area.

Section: Biogasmentioning

confidence: 99%

Bibliometric analysis of research trends in engineering for rural development

Knapczyk

Francik

Pedryc

et al. 2018

“…For example, the article [3] states, that electricity from biogas is a promising direction of energetics and is an additional source of income in rural areas. In particular, biogas production from plant biomass is widespread [4]. In addition, vegetable raw materials are used for production of fuel pellets [5] and bioethanol [6].…”

Section: Introductionmentioning

confidence: 99%

Structural models of agroecosystems and calculation of their energy autonomy

Golub

Kukharets

Yarosh

et al. 2019

The results of the research in structural models with complete energy autonomy of agroecosystems (electricity and heat energy of own production) are presented. The aim of the work is to show the opportunities of complete energy autonomy of agroecosystems by producing and using their own electrical and thermal energy with observance of humus balance. Structural models of functioning of agroecosystems with organic and intensive production are presented. The models include growing of winter wheat, corn for silage, grain, winter rape, barley, sugar beet, and perennial grasses, sugar and honey production, mushroom and fish cultivation, and compost production. The model with organic production additionally provides for the production of pork, beef, chicken, milk, eggs, and oil. In addition, the proposed models provide for the production of diesel biofuels and bioethanol in the amount necessary to ensure the operation of mobile equipment, as well as biogas and generator gas for heat and electricity. The criterion of ecological stability of the proposed models of agroecosystems is the observance of humus balance. The analysis of the presented models allows asserting that complete energy autonomy of agroecosystems with a positive humus balance in the soil is possible. In agroecosystems with organic production the most heat energy-up to 50 % can be obtained by using straw pellets. Biogas can provide up to 20 % of the needs thermal energy, diesel biofuels-up to 16 %. 14 % of heat energy can be obtained from burning straw rolls. The production of electricity from wood gas produced from straw pellets provides 54 % of all electricity needs. Due to the use of biogas, up to 29 % of electric energy is provided, and through the use of diesel biofuels-up to 17 %. All the needs for heat energy for agroecosystems with intensive production can be provided by 80 % through the use of biogas and by 20 %-due to straw briquettes and pellets. All electricity costs for agroecosystems with intensive production can be provided through the use of biogas.The electric energy obtained through the use of wood gas resulting from gasification of straw pellets or briquettes can be sold at a green rate.

“…A wide variety of raw materials can be used. In particular, the production of biogas from both plant biomass [3] and biomass of animal origin [4] has become widespread.…”

Section: Introductionmentioning

confidence: 99%

Study of energy costs in process of biomass mixing in rotary digester

Kukharets

Golub

Szalay

et al. 2019

One of the main problems in the biogas production is stratification of biomass substrate in the digester. To eliminate biomass stratification it is proposed to use rotating digesters. However, such mixing can have significant energy costs. Therefore, the study of the efficiency of rotating methane tanks is required. The energy efficiency of biomass mixing in a rotary digester is studied. The digester vessel is made in the form of a horizontal cylinder rotating around the horizontal axis. The digester is partially immersed in the liquid, which is located in the outer casing. Due to the ejection of the digester from the liquid, a lifting force arises, which unloads the bearings of the digester axis. The friction force in the bearings is reduced and, accordingly, the energy consumption for rotating the methane tank and mixing the substrate is reduced. Experimental determination of the influence of technological and structural parameters of the methane tank and substrate parameters on the change in power consumption during mixing was carried out using an experimental bioreactor (inner radius R = 0.2 m, working length L = 0.6 m). Analysis of the experimental studies allows us to conclude that at the values of the filling factor less 0.93 the requirement floating of the reactor in the liquid is provided, but the reactor capacity is used irrationally, which leads to an increase in specific energy consumption. And at more than 0.93, the navigation condition is not provided, which leads to a sharp increase in energy losses in the bearings during the digester rotation. As a result of the research it was found that when filling the reactor with biomass at a value of 92 to 94 % of the volume and its immersion in the liquid up to 97 % in height, the lowest energy costs for mixing the substrate will be observed.