Toxic potency-adjusted control of air pollution for solid fuel combustion

The combustion of solid fuels, including coal and biomass, is a main anthropogenic source of atmospheric particulate matter (PM). The hidden costs have been underestimated due to lack of consideration of the toxicity of PM. Here we report the unequal toxicity of inhalable PM emitted from energy use in the residential sector and coal-fired power plants (CFPPs). The incomplete burning of solid fuels in household stoves generates much higher concentrations of carbonaceous matter, resulting in more than one order of magnitude greater toxicity than that from CFPPs. When compared with CFPPs, the residential sector consumed only a tenth of solid fuels in mainland China in 2017, but it contributed about 200-fold higher of the population-weighted toxic potency-adjusted PM2.5 exposure risk. We suggest that PM2.5-related toxicity should be considered when making air pollution emission control strategies, and incomplete combustion sources should receive more policy attention to reduce exposure risks.

Assessment of Interchangeability of Fuels Used in the Process of Heat Production and Comparison of Their Selected Characteristics: A Case Study

Exchangeability means the possibility of the fuel changing, with conservation of the required energy and environmental criteria. The assessment of fuel exchangeability should be realized by a suitable method, which must reliably present the possibility of the exchangeability of fuels, or reject it. In the presented paper, research on the exchangeability of solid fuels in the field of heating production is surveyed by the case study. Based on the available published knowledge from previous studies on fuel exchangeability, the statistical method was chosen for evaluation. The application of this method is useful. For example, by evaluating the exchangeability of natural gas, the manuscript will describe its application for the field of solid fuels in heat production. The research evaluated and analyzed the sample of 12 fuels. For each fuel sample, 35 gas attributes were measured, which were classified into separate flue gas attribute groups: ash content, combustion heat, heating capacity, sulfur content, combustible content, water content, emission factor, carbon content, hydrogen content, and oxygen content. Attributes of flues were evaluated and grouped according to the fuel properties—ash content and combustion heat, sulphur content, water content, emission factor, carbon content, hydrogen content, nitrogen content, oxygen content, and combustible content.

SPECIFIC FEATURES OF DETERMINING THE DESIGN OF OXYGEN TUBE TIPS UNDER NON—STATIONARY CONDITIONS OF CONVERTER MELT WITH PRELIMINARY HEATING OF SCRAP

The results of calculating the parameters of the tips of oxygen lances, taking into account the preheating of scrap metal in the converter due to the combustion of solid fuels in the modern raw material conditions of a metallurgical enterprise of Ukraine, are presented. The substantiation of the design of blowing devices is provided. The results of calculating the geometric parameters and the coefficient of off-design for standard and experimental tips of oxygen lances are presented. Using numerical methods, the value of the diameters and length of the supercritical part of the nozzle was obtained. It is shown that with a decrease in the blast flow rate, it is advisable to decrease the length of the supercritical part of the nozzle, which is fully correlated with the literature data. The change in the coefficient of off-design was determined for the studied range of oxygen consumption (600—1100 m3 / min) for standard and experimental handpieces. It is shown that the value of the coefficient of off-design is in the range of 0.52—0.98 and 1.30—2.30, respectively, for 5– and 6–nozzle standard tips. For experimental tips, this figure is 1.00—1.70. Tuyeres with experimental tips, at the pressure available in the shop, reliably operate in the range of oxygen consumption 650—950 m3 / min and allow increasing the oxygen consumption at the beginning of the blowdown to 1000—1100 m3 / min and more, if necessary. The resulting saving effect from the introduction of the modernized tips is: a decrease in the oxidation of the final slag 1.22—1.70 %; reduction in the specific consumption of lime 0.29—1.81 kg / t; reduction of specific consumption of metal charge 0.26—0.38 kg/t.

Restructuring Simulation of the Ventilation Network

Worldwide, the demand for raw materials and materials is constantly increasing, being proportional to the growth of the population. In this sense, the demand and production of solid fuels such as coal has grown steadily. At the level of the European Union, due to the restrictive coal extraction policy, production has steadily decreased and coal-producing countries have had to implement closure programs with strict deadlines. As mining networks shrink, there is an intensification of risk factors due to changes in the ventilation system. The paper presents the restructuring of a complex ventilation network.