International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Analysis of physicochemical and operational performance of petroleum and alternative motor fuels showed that their lower heat of combustion can differ significantly. However, the heat of combustion of fuel-air mixtures of these fuels differs slightly. Therefore, the assessment of energy and fuel-economic performance of the engine during its operation on different fuels is proposed to do the calculation method for the consumption and heat of combustion of fuel-air mixtures. According to the developed method, engine power and fuel consumption during engine operation on biodiesel, biomethane and petroleum diesel fuel were determined. To determine the heat of
combustion of fuel-air mixtures, the lower heat of combustion of fuels was used. Fuel-air consumption was determined by engine displacement and crankshaft speed. The tests show that the highest power and lowest fuel consumption of the engine running on petroleum diesel fuel and slightly worse values of the engine running on biodiesel. The gas engine with spark ignition converted from diesel running on biomethane shows the lowest indicators.

Pre-harvest sprouting is the premature germination of cereal seeds so that the embryo starts growing while still on the head in the field. Grain germination before the harvest is a serious problem in many wheat-growing areas of the world. The grain and flour quality parameters impacted by pre-harvest sprouting are strongly related with climatic variables and soil water condition. This process especially occurs when wet conditions delay harvest. Spouted seed is usually inadequate for flour productions. Products made of sprouted flour are generally unacceptable to producers and consumers. Moreover, it is also often inadequate as feed because microbiological contamination. However, it seems that such kind of waste grain can be utilized for energetic purposes. The aim of the present work was to study the grinding process of sprouted wheat. The heat of combustion of sprouted grain and sound grains was also determined. Three-day germinated kernels of three wheat varieties were used for investigation. After germination the wheat kernels were dried at 40°C by using an air dryer to obtain the same moisture as that of the grain before sprouting (14.0% w.b.). The sound kernels were used as a control sample. The sprouted and the sound samples of grain were ground by using the knife mill MG-200. The results showed that the sprouting of wheat had a significant influence on the grinding process, both on the particle size distribution and grinding energy requirements. The sprouting caused a decrease in the average particle size and value of specific grinding energy in all cultivars. The values of specific grinding energy ranged average from 21.6 kJ·kg-1 to 23.6 for kJ·kg-1 fore sprouted and sound kernels, respectively. The heat of combustion of sprouted grain was only slightly lower value of this parameter obtained for sound grain and ranged from 15.9 to 16.5 MJ/kg.

In connection with the observed dynamism of changes on the energy market regarding generation of energy from sources other than coal, more attention was paid to the use of "clean", low-emission technologies. Bearing in mind the need to search new, alternative energy sources, the aim of the study was to investigate and analyze the properties of grain biomass, such as rice and corn, as a fuel. To achieve the goal, the research problem has been formulated: how the fragmentation degree and the type of biomass affects such energy properties as heating value and heat of combustion. To resolve the problem, the properties of white rice, black rice, red rice and corn before and after grinding were analysed. The results show that white rice has the biggest value of heat of combustion before grinding, red rice – the lowest. White rice has the biggest heating value for whole grain, red rice – the lowest. The research allows to state that grinding operations result in increasing energetic properties of biomass. It can be also assumed that biomass is a good substitute of fossil fuel.