Rational use of natural sources. Рубрика в журнале - Nanotechnologies in Construction: A Scientific Internet-Journal
Energy resource efficient designs of small-sized water circulating cooling devices
Статья научная
To use natural sources in rational way, plantsof continuous cooling of closed systems of recycling water supply are used. The paper presents designs of small-sized devices for recycling water cooling which are energy resource effective due to twisted motion of air flow, moving countercurrent to the cooled water. Heat and mass transfer is a nanotechnological process that occurs at the intermolecular level. Methods and materials. Countercurrent mini cooling towers are widely used in all industries, but there are some disadvantages, the main of which is the insufficient interaction time of the moving phases. Screw motion of air flow is created by the tangential supply of cooling air in the bottom part of cylindrical small-sized cooling tower. The rate of rotary motion decreases as air flow moves up in cooling towers, and vertical parameter of the rate – increases. Such scheme of the air flow motionmakes it possible to decrease average vertical parameter of the rate and to increase phases contact time. Laboratory research. To determine the technological and hydroaerothermal characteristics, as well as to estimate the efficiency of cooling recycled water, and to carry out mass-heat exchange at the intermolecular stagean experimental facility of small-sized cooling tower with twisted air flow has been developed. Conclusions. In accordance with the exponential law it is shown that the rotational component decreases at increasing height, and in accordance with the power law the vertical component increases component with the exponent ~1,79. It is determined that moisture content x and air temperature tv in the volume of the height of the sprinkler varies according to a power law, in particular for a screw cooling tower proportionally x ~ h0,83, tв ~ h1,25. It was determined that the coefficients of mass transfer βxv and heat transfer αv of a mini cooling tower with twisted air flow at the intermolecular level with equal irrigation densities are 20% higher than the coefficients of a mini cooling tower with counter-current flow. Also it has been determined experimentally a dependence of aerodynamics resistance coefficient of the twisted irrigator of the cooling tower on criterium Refor air flow, and it was determined that it decreases like Re–K2 as the exponent K2 varies in the range 0.114÷0.193 depending on the irrigation density.
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Статья научная
Results of a research of efficiency of sorbents on the basis of the waste of production and processing of micaceous quartzites (MQ), montmorillonite clays (MC) modified by humic connections (HC), received by extraction of waste brown coal are shown. Chemical composition of mica quartzite processing waste depending on the fraction size was previously investigated: element structure by method of the power-dispersive X-ray fluorescent analysis and mineral structure by method of X-ray phase analysis, for purpose of interrelation establishment between the structure of fraction and adsorptive properties of the received composite sorbents and also for the purpose of an exception as a part of MQ and, respectively, a sorbent of dangerous and toxic substances I-III of hazard classes. The efficiency of adsorption of the obtained sorbents was studied, an increase in sorption activity was found depending on composition of sorbent and method of modification (preliminary temperature processing and drawing on a surface of a sorbent of HC nano- and a microdimensional layer). It is determined that the greatest efficiency of adsorption of ions of heavy metals is observed for the sorbent which underwent temperature modification at 800оC and then HC covered with a layer up to 1% of masses. Use of waste of MQ containing 40–60% of quartz (SiO2) in composition with MC and with further modification of a surface (up to 1% of masses.) humic connections will allow receiving highly effective, universal and inexpensive sorbents for sewage treatment from heavy metals and other pollutants. The offered composite sorbents will allow to solve several ecologically important problems in a complex: to carry out effective purification of industrial sewage (machine and instrument-making, metallurgical, petrochemical and other enterprises) of heavy metals ions and to utilize waste of micaceous quartz processing of and brown coal extraction.
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