New advanced and simple two-dimensional (2D) models of sessile droplet heating and cooling and evaporation are suggested. In contrast to the earlier developed one-dimensional (1D) model, based on the assumption that heat supplied from the supporting surface is homogeneously and instantaneously spread throughout the droplet, both new 2D models consider the spatial distribution of this heat. The advanced 2D model is based on the numerical solution to the equations of conservation of mass, momentum, vapor mass fraction, and energy with standard boundary and initial conditions, using COMSOL Multiphysics code.
View Article and Find Full Text PDFA wide range of wastes can potentially be used to generate thermal and electrical energy. The co-combustion of several types of waste as part of water-containing waste-derived fuels is a promising method for their recovery. In this research, we use thermogravimetric analysis and differential scanning calorimetry to study the thermal behavior and kinetics of coal slime, biomass, waste oils, and blends on their basis.
View Article and Find Full Text PDFThe processes of interaction of liquid droplets with solid surfaces have become of interest to many researchers. The achievements of world science should be used for the development of technologies for spray cooling, metal hardening, inkjet printing, anti-icing surfaces, fire extinguishing, fuel spraying, etc. Collisions of drops with surfaces significantly affect the conditions and characteristics of heat transfer.
View Article and Find Full Text PDFThis study is based on the analysis of a set of industrial sectors (coal processing, wood processing, transport, oil, and water treatment) in order to identify the amount and type of combustible waste suitable for incineration. The main ignition and combustion parameters of these wastes have been experimentally obtained from their direct individual incineration in the original form and as part of a slurry based on wastewater. It has been established that a set of parameters allow waste-derived fuel mixtures to compete with coal dust and fuel oil with an environmental advantage.
View Article and Find Full Text PDFThe total volume of the coal processing wastes (filter cakes) produced by Russia, China, and India is as high as dozens of millions of tons per year. The concentrations of CO and CO in the emissions from the combustion of filter cakes have been measured directly for the first time. They are the biggest volume of coal processing wastes.
View Article and Find Full Text PDFThis introductory study presents the analysis of the environmental, economic and energy performance indicators of burning high-potential coal water slurries containing petrochemicals (CWSP) instead of coal, fuel oil, and natural gas at typical thermal power stations (TPS) and a boiler plant. We focus on the most hazardous anthropogenic emissions of coal power industry: sulfur and nitrogen oxides. The research findings show that these emissions may be several times lower if coal and oil processing wastes are mixed with water as compared to the combustion of traditional pulverized coal, even of high grades.
View Article and Find Full Text PDFNegative environmental impact of coal combustion has been known to humankind for a fairly long time. Sulfur and nitrogen oxides are considered the most dangerous anthropogenic emissions. A possible solution to this problem is replacing coal dust combustion with that of coal water slurry containing petrochemicals (CWSP).
View Article and Find Full Text PDFSci Total Environ
November 2017
High concentrations of hazardous anthropogenic emissions (sulfur, nitrogen and carbon oxides) from solid fuel combustion in coal burning plants cause environmental problems that have been especially pressing over the last 20-30 years. A promising solution to these problems is a switch from conventional pulverized coal combustion to coal-water slurry fuel. In this paper, we pay special attention to the environmental indicators characterizing the combustion of different coal ranks (gas, flame, coking, low-caking, and nonbaking coals) and coal-water slurry fuels based on the coal processing waste - filter cakes.
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