The cold start period of an internal combustion engine (ICE) is a dominant source of hydrocarbon (HC) and carbon monoxide (CO) emissions. This paper analyzes an innovative ejector system for distributing ionized air directly into the exhaust system to accelerate pollutant oxidation. Analytical results demonstrate that the system achieves an ejection ratio ω = 0.187 at an exhaust temperature of 450 K, while a 180 W heater provides the necessary thermal compensation to maintain the mixture temperature above the 380 K activation threshold. Experimental validation confirmed that ionized air initiates low-temperature oxidation (afterburning), evidenced by a 5.0% vol. increase in CO2 concentration. This synergistic fluid-thermal and chemical strategy reduces the catalyst’s critical inactivity period from 120 s to 85 s, offering highly efficient method for meeting stringent emission regulations.

The use of renewable energy sources is imposed as an imperative for the competitiveness and stable energy policy of companies. The basic production equipment in the "Kreka" coal mine in Tuzla has electrical plants with a total peak load of 12 MW, and the costs for electrical energy exceed €3.5 million annually. The paper analyzes the suitability of infrastructure facilities and devastated areas of the Kreka Coal Mine in Tuzla for the construction of photovoltaic power plants and the effects of such plants. The results of the analysis show a significant resource for the installation of photovoltaic power plants with a capacity of 230 MW. The production of electricity from these photovoltaic power plants enables a reduction of emissions into the air by 190 t/year of particle emissions, by 316.2 •103 t/year of CO2 emissions, by 58.15 t/year of SO2 emissions and by 251.9 t/year of emissions NOx. With the subsidized purchase of electricity, it is possible to return the investment within 6 years.

Determination of multiphase flow inside PC boiler plant is of particular importance for the process control of the boiler and its efficient operation. Nowadays numerical modeling is used as an advanced tool in improvement of this or similar process. Separation of coal particle in aero-mixture channel, after pulverization, represent an important process which has a big effect on boiler efficiency, and its determination represents an important step. In this paper, numerical modeling of multiphase flow inside aero-mixture channel and low emission burner of boiler OB-650 are exposed in several steps from 3D modeling, discretization of fluid domain, setting the physical and mathematical model to validation of same model. Main goals of the same process is to obtain valid numerical model of observed problematic, that will give us data about model parameters that can be used for modeling of the same process with different inlet boundary conditions, and also to obtain appropriate specific process parameters that can be used for rising of level of efficiency and utility of boiler plant in some steady operating modes.

Velocity of solid particles in aero-mixture channel has been recognized as the most significant factor that has an influence on erosion. In this paper, numerical study of particle erosion in aero-mixture channel was conducted due to the main parameters that have the greatest impact. Pulverised coal boiler OB650 is supplied with an aero-mixture (pulverised coal and flue gases) through distribution channels, 2358 Amel Mešić et al. where the distribution of the same aero-mixture is regulated with a tilt of regulation dumper. These types of regulation cause the problems that have greater impact on the internal structure of the same distribution channels. It is concluded that the best way to determinate that problems is with CFD tool. In this case CFD tool was used to simulate the flow field inside the channel, using EulerLagrangian mathematical approach.