Influence of wood component on physical and chemical transformations during high temperature heating of composite fuel based on bituminous coal

Experimental studies of ignition delay time for mixtures of dispersed hard coal of two types and milled wood over a wide temperature range have been performed. Time of total completion of organic part pyrolysis of both components at different concentrations have been established in order to assess the prospects for such fuels application in large- and small-scale power engineering (combustion in boiler furnaces of different capacities). It has been established that simultaneous thermal decomposition of mixture of coal and wood particles leads to a significant change of pyrolysis temperature range and release of anthropogenic gases (sulfur and nitrogen oxides) in case of high-temperature heating of the mixture based on lean coal. The same effect, but in much smaller scale, has been recorded for a mixture based on long-flame coal. A hypothesis has been formulated on the mechanism of sulfur and nitrogen oxides precipitation during thermal decomposition of the mixture of lean coal and wood particles as a result of interaction between transitory gaseous and solid pyrolysis products of coal and wood in the temperature range up to 1000°C. Prospects of applying the milled coal and wood mixtures as fuel for steam and hot water boilers have been substantiated. With a small decrease of energy characteristics of such fuels, compared to homogeneous coals, significant improvement of ecological and economic characteristics of the fuel combustion processes can be achieved. It has been shown that vital synergistic effect of co-combustion of coal and wood particles is achieved only with certain coals

Research of Heat and Mass Transfer Processes in the Nodes of Free-Flow Micro-Hpp With the Use of 3D Technology

In the article the analysis of existing micro-hydro turbines. Created 3D experimental model. Designed and developed an experimental stand for testing micro-turbine. Investigated options for generators on permanent magnets, selected the optimum scheme and developed a prototype three phase generator with permanent magnets

Analysis of composite fuel application possibility based on coal and oats husks in industrial power engineering

Experimental studies were conducted to determine the energy and technical characteristics of composite fuels from T grade coal (Alardinsky deposit) and oats (Shegarsky district, Tomsk region). An effective concentration of composite fuel of 50% / 50% is established, at which the heat of combustion is reduced by less than 2%, the ash content is up to 44%, and the fly ash output is up to 48%

Applying composite fuels based on coal and finely dispersed wood in heat power engineering

Results of experimental research of thermal decomposition of composite fuels based on 2B brown coal (Borodinskoe deposit) and wastes of timber industry (finely dispersed wood) are presented. Elemental composition of researched fuels has been defined and technically analyzed. Kinetic constants have been calculated within Arrhenius model of the first order. It has been determined that with an increase of wood concentration up to 50% in composite fuel, its energy characteristics decrease by less than 2%, the maximum temperature of fuel thermal decomposition reduces by 9%, while SOx and NOx yield reduces by 50%, and fly ash – by 75%. An effective composite fuel composition of 50%/50% has been established. Results of performed experimental studies illustrate possible applications of composite fuels based on brown coal and wood at thermal power plants

Study of Electrophysical Intrastratal Gasification at Different Coal Heating Rate

Experimental instrumental multi-method research, electrophysical ihtrastratal gasification of antracite with further definition of quantitative syngas composition and its combustion heat design at different heating rates. It was stated that concentration of carbon dioxide CO[2], hydrogen H[2] decreases with heating rate increase in received syngas, and there is rise of carbon monoxide CO concentration. The results of the research showed that heating rate increase leads to a small rise of combustion heat as decrease of H[2] and CH[4] concentration is compensated with increase of CO

Research of wood waste concentration influence on composite fuel energy characteristics based on low-grade 2b coal from "Borodinskoe" deposit

A pyrolysis process of different coal samples into three different types of oxidizing medium (argon, air and steam) were studied by means of thermogravimetry. Two coal types with different metamorphism degree (lignite and bituminous coal) were used. The experimental procedure was carried out in non-isothermal conditions in temperature range from 373 K to 1273 K with 20 K/min heating rate. Purge gas consisted of argon and oxidizer with volumetric ratio 1:24 and had 250 ml/min flow rate. Kinetic parameters were defined by fitting procedure using Arrhenius-type equation with the first order reaction rate on conversion distribution function. The ignition and burnout indexes were calculated to evaluate sample reactivity at different oxidizing mediums. The highest reactivity values in same atmosphere were obtained for lignite because of higher particle special surface area. For same samples the higher reactivity was obtained in steam medium. The conclusion about some kind of synergy between carbon oxidation and pyrolysis could be made

Research of Heating Rates Influence on Layer Coal Gasification of Krasnogorsky And Borodinsky Coal Deposit

Experimental research of heating rate influence on coal samples gasification process of Krasnogorsky and Borodinsky coal deposit ranks A and 2B was done to define optimal heating mode in high intensification of dispersal of inflammable gases conditions. Abundance ratio of carbon monoxide and nitrogen monoxide, water vapor, carbon dioxide at four values of heating rate within the range of 5 to 30 K/min. with further definition of optimal heating rate of coals was stated

Research of rheological properties improvement methods of coal-water fuel based on low-grade coal

Experimental studies of coal-water fuel (CWF) rheological properties based on 3B brown coal have been conducted using different processing methods, such as rotary flows modulation device (RFMD), sodium hydroxide and lignosulfonate. Physicochemical properties of initial solid fuel have been determined using JEOL JCM 6000 microscope. Optimal method of coal-water treatment has been determined based on obtained data considering its influence on viscosity and sedimentation stability of coal-water slurry (CWS)

Research of rheological properties improvement methods of coal-water fuel based on low-grade coal

Experimental studies of coal-water fuel (CWF) rheological properties based on 3B brown coal have been conducted using different processing methods, such as rotary flows modulation device (RFMD), sodium hydroxide and lignosulfonate. Physicochemical properties of initial solid fuel have been determined using JEOL JCM 6000 microscope. Optimal method of coal-water treatment has been determined based on obtained data considering its influence on viscosity and sedimentation stability of coal-water slurry (CWS)

Increase of Engineering Students Training Level

The article considers the problem of the widespread introduction of computer technology in the training of students in technical areas. This leads to a significant deterioration in the quality of practical training. Implementation in the educational process of the laboratory complex, which represents a real model of the power plant, has led to improved academic achievement in core subject areas. This equipment allowed the students to gain practical skills for different types of works with the equipment on the basis of the University, and also helped to increase the interest of students in carrying out the laboratory and practical work