Thermogravimetric, kinetic study and gas emissions analysis of the thermal decomposition of waste-derived fuels.

A 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.

Hydrophilic and Hydrophobic Surfaces: Features of Interaction with Liquid Drops.

The 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.

Gas composition during thermochemical conversion of dry solid fuels and waste-derived slurries.

Coal has long remained a promising and widely used energy resource all over the world. Special emphasis is usually put on the research and development of environmentally friendly technologies for the use of coal and coal processing waste. The development of slurry fuels based on coal waste is one of the promising ways to use raw materials with energy potential, recover wastes, and reduce the environmental load.

Multiple-criteria decision analysis to substantiate the prospects of industrial and solid municipal wastes as slurry fuel components.

This article investigates the recovery of typical wastes (coal slime, sawdust, cardboard and tire pyrolysis residue) as part of high-moisture slurry fuels. Using a laboratory furnace, the ignition and combustion characteristics of fuels as well as NO and SO emissions were determined. Using multiple-criteria decision-making (MCDM) methods and experimental results, we access the performance of four different slurry fuels in comparison with bituminous coal.

Emissions from the combustion of high-potential slurry fuels.

Slurry fuels based on wood and coal processing and petroleum refinery waste are an environmentally friendly and economically feasible alternative to the conventional solid fuel-coal. As part of this experimental research, we compared a set of fuels (coal and coal-water slurries with and without petrochemicals) by normalizing and calculating the specific concentrations of pollutants from their combustion. The pollutant concentrations were normalized with respect to the mass of burnt fuel, the thermal energy released by combustion, specific mass emissions per unit time, specific maximum mass emissions, and specific mass emissions per 1 kg of fuel equivalent or 1 MJ of thermal energy.

Collisions of Two-Phase Liquid Droplets in a Heated Gas Medium.

The paper presents the experimental research findings for the integral characteristics of processes developing when two-phase liquid droplets collide in a heated gas medium. The experiments were conducted in a closed heat exchange chamber space filled with air. The gas medium was heated to 400-500 °C by an induction system.

Gas-Vapor Mixture Temperature in the Near-Surface Layer of a Rapidly-Evaporating Water Droplet.

Mathematical modeling of the heat and mass transfer processes in the evaporating droplet-high-temperature gas medium system is difficult due to the need to describe the dynamics of the formation of the quasi-steady temperature field of evaporating droplets, as well as of a gas-vapor buffer layer around them and in their trace during evaporation in high-temperature gas flows. We used planar laser-induced fluorescence (PLIF) and laser-induced phosphorescence (LIP). The experiments were conducted with water droplets (initial radius 1-2 mm) heated in a hot air flow (temperature 20-500 °C, velocity 0.

Effective incineration of fuel-waste slurries from several related industries.

This 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.

Municipal solid waste recycling by burning it as part of composite fuel with energy generation.

In this work, it has been shown that the involvement of composite fuels in thermal power engineering will enable to recycle both industrial and municipal combustible wastes while saving fossil fuels. The ignition and combustion stability of composite fuel droplets up to their complete burnout was experimentally substantiated under the conditions typical of boiler furnaces, using the example of several fuel compositions with wood, food waste, plastic, and cardboard, each added separately. The values of the guaranteed delay times for the ignition of droplets with a size of about 1 mm were established for the considered fuel compositions in a wide range of the ambient temperature variation (600-1000 °C).

Experimental evaluation of main emissions during coal processing waste combustion.

The 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.

Coal-water slurries containing petrochemicals to solve problems of air pollution by coal thermal power stations and boiler plants: An introductory review.

This 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.

Environmental indicators of the combustion of prospective coal water slurry containing petrochemicals.

Negative 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).

Environmentally and economically efficient utilization of coal processing waste.

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.