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Summary Master's work
Optimization technology
endothermic firing
polydisperse carbonaceous materials
in furnaces of a boiling layer The useful model concerns technics эндотермического roasting polydisperse карбонатных materials in a boiling layer and can be used in metallurgical, chemical and building industries. The furnace of a boiling layer for roasting of a loose material (SU, № 924488, кл is known. F 27 In 15/00, опубл. 30.04.1982г.), including zones of roasting of limestone and cooling to exhaust, the hot cyclone interconnected with a zone of roasting and, located over it, the heating zone, a deaf partition between a zone of roasting and the heating zone, placed with formation of the chamber isolated from below from a zone of roasting, and interconnected with a heating zone through газораспределительную a lattice, thus on a surface of the deaf partition turned upwards, it is established tubular газораспределитель with the apertures executed in the top part of pipes and focused vertically upwards, and the configuration of pipes газораспределителя can be executed in the form of a coil with parallel sites, a collector with taps or Archimedes spirals. To lacks of the known furnace of a boiling layer for roasting of a loose material, it is necessary to carry its low operational reliability and insufficient thermal efficiency as on a horizontal cut of apertures tubular газораспределителя, focused vertically upwards, at fluctuations in a boiling layer, arise sharp pressure fluctuations that leads просыпанию a material in inside tubular газораспределителя. It leads to infringement of uniform distribution of air on apertures tubular газораспределителя and - to infringement газодинамического a mode that leads to furnace failure at critical accumulation of a material in the chamber. The specified circumstances conduct to idle times of the furnace for cleaning of pipes газораспределителя and chambers, to the over-expenditure of fuel and to finished goods losses. The closest analogue on technical essence and reached result to the offered furnace of a boiling layer for limestone roasting (RU № 2224196 C2, кл. F 27 In 15/00, With 04 In 2/10, опубл. 20.02.2004г.), containing a zone of roasting with газораспределительным the device and подрешёточной the chamber and a zone of cooling with tubular газораспределителем, connected to the pressure-blowing means, executed in the form of pipes with apertures in the bottom part of their lateral surfaces (the bottom punching), established horizontally with a backlash in 4 - 12 maximum sizes of particles processed to exhaust among themselves and with the case of a zone of cooling, the reexact device for an unloading to exhaust from a cooling zone, and подрешёточная the chamber of a zone of roasting is connected with надслоевым space of a zone of cooling by an air line, and an input of the reexact device for an unloading to exhaust from a cooling zone is located in the bottom basis conic подрешёточной chambers of a zone of cooling. Lacks of the closest analogue concerns the following. In a cooling zone a boiling layer to exhaust it is formed above a horizontal cut of apertures of the lateral surfaces of pipes executed in the bottom part газораспределителя, hence apertures and an air stream from them are focused downwards, means известь cannot get in inside tubular газораспределителя at work of the furnace and at its stop. In this case, below a cut of apertures tubular газораспределителя, the material is in a dense bed condition, thus air streams from apertures tubular газораспределителя directed vertically downwards, are reflected from a surface of a dense bed of particles to exhaust for a turn vertically upwards. As, a surface of a dense bed of particles to exhaust is on distance about 0,5 external diameters of pipes газораспределителя the air stream gets to the limited, practically closed space, that sharply increases aerodynamic resistance tubular газораспределителя (from 1500 – 2500 Pases, to 5000 – 7500 Pases). So, at increase in resistance tubular газороспеделителя in 1,5 - 2,5 times it is necessary to reduce height of a boiling layer in a cooling zone so – to worsen conditions of heat exchange and thermal к.п.д. Furnaces of a boiling layer as a whole to reduce its productivity. Thus reduction of a boiling layer of a zone of cooling can appear insufficiently (on conditions existence of a boiling layer of a zone of cooling is required necessary its minimum height) then it is necessary to reduce height of a boiling layer of a zone of roasting, and it can lead to decrease in quality of roasting and quality of production – to exhaust. In a basis of the given useful model the task in view of improvement of a design of the furnace with a boiling layer for эндотермического roasting polydisperse карбонатных materials in which for the account of design features tubular газораспределителя a cooling zone to exhaust, changes the scheme of distribution of air, and orientation of apertures tubular газораспределителя, that leads to decrease in the expense of fuel on process, to improvement of quality and a material exit. The task in view is reached by that in the furnace with a boiling layer for эндотермическогообжига polydisperse карбонатных materials:
Result of use of an offered design of the furnace with a boiling layer for эндотермического roasting polydisperse карбонатных materials is the increase of its operational characteristics expressed in maintenance of steady technological process, at decrease in aerodynamic resistance tubular газораспределителя in 1,5 – 2,5 times and corresponding increase in useful weight of a boiling layer. Thus penetration of particles to exhaust in pipes газораспределителя, an event as a result of fluctuation of a boiling layer of particles to exhaust in a cooling zone, in this case is not a limiting stage of process as particles transit leave through apertures of the bottom punching in подрещёточное space of a zone of cooling. Also apertures in lateral walls of pipes tubular газораспределителя the bottom punching are executed with a profile in the form of the truncated cone, and an aperture of the top punching – in the form of a lateral surface of the turned truncated cone, that, according to a direction of possible penetration of particles in tubular газораспределителя, excludes accumulation of particles on a cut of apertures of the top punching and, on the contrary, promotes gathering проникших particles in конусной to bottom punching forming apertures. For limestone and to exhaust крупностью from 0,003 to 0,020м live section (relation of the total area of apertures to the zone area in this section, %) газораспределительной lattice in boiling layer makes 2,5 – 4, 0÷6,0 – 8,0 (Gelperin N.I., etc. technics Bases псевдоожижения. М: chemistry. 1967, 664с.), in appropriate way and the parity of the area of apertures of the bottom and top punching will make, at least, from the point of view of aerodynamic conditions of existence of a boiling layer, 1,5 – 3,0 (6,0/4,0 ÷ 8,0/2,5). On the other hand, the size of particles which get in tubular газораспределителя, does not exceed diameter of apertures of the top punching, however these particles can have the form of the cylinder with a parity of the least and greatest size to 2,0 (Люйкен V.Podgotovka of crude materials to domain fusion. – m: State scientifically – technical publishing house of the literature on black and nonferrous metallurgy. 1959. – 412с.), and they can block apertures of the bottom punching. Possibility of jamming of apertures of the bottom punching by two particles with the maximum and minimum linear size that will make 3,0 (1,0 - minimum + 2,0 - the maximum size of particles) is simultaneously admissible. Therefore the area of apertures of the bottom punching should be provided in 4,0 – 9,0 (πd2н / π d2в = 22/π12 - 32/π12 = 4,0 – 9,0, where dн and dв, accordingly, diameters of apertures of the bottom and top punching) большей, than the area of apertures of the top punching. Т.о., the areas of apertures tubular газораспределителя the top and bottom punching should correspond as 1,5 – 3,9 ÷ 4,0 – 9,0, that will allow penetrations and accumulation with забиванием and an exit of their system tubular газораспределителя and furnaces as a whole. For reduction of probability of jamming of large particles the sharp edge of an input (top) and an exit (the bottom punching) apertures is executed. Result of the listed actions is decrease in the expense of fuel, improvement of quality and an exit to exhaust. On fig. 1 the general view of an offered design of the furnace with a boiling layer for эндотермическогообжига polydisperse карбонатных materials is presented. The furnace has a zone of roasting 1 – газогорелочное the device of a zone of roasting 1 with gas torches 2 and air apertures 3, the zone of cooling 4 located in the separate case, an air line 5 established between a zone of roasting 1 and zone of cooling 4, подрешеточную the chamber of 6 zones of cooling 4, tubular газораспределитель 7 zones of cooling 4, with apertures 8 (the top punching) and 9 (the bottom punching), an air line 10 connected to giving of air, the reexact device 11 of a zone of roasting 1 in a zone of cooling 4, the reexact device 12 of a zone of cooling 4 for the finished goods unloading which input is located in the bottom basis подрешеточной chambers of 6 zones of cooling 4, a regulator of giving of air 13, подрешеточную the chamber of 14 zones of roasting 1. Offered to bake works as follows. Limestone крупностью 0,003 - 0,012, 0,0015м is loaded into a zone of the roasting 1, burnt известь with the reexact device 11 is overloaded in a zone of cooling 4 and, after cooling, by the reexact device 12 is unloaded from a zone of cooling 4 – from the furnace. Air on cooling to exhaust and a boiling layer 9 top punchings move in воздухов 10 and air apertures 8 bottom and apertures, further нагретый air arrives in подрешёточную the chamber of 14 zones of roasting 1 and through gas torches 2 and air apertures 3 in a zone of roasting 1 on burning of natural gas. Received газо - the air mix burns down in a boiling layer of a zone of roasting 1. Resistance tubular газораспределитель thus will decrease 3750 – 6350 to 1000 – 1500Па for the account of combination of the top and bottom punching, i.e. there are more low, than at known furnaces. The boiling layer of a zone of cooling 4 accordingly will increase in comparison with known furnaces with 10000Па to 11000 – 11500Па. Thus, apertures of the top punching tubular газораспределитель 7 are to a lesser degree subject забивания from – for конусности and a sharp edge on an exit of air streams of a stream (and an input of particles in inside), and, at penetration of particles to exhaust inside трубчатыго газораспределителя 7, they leave through apertures of the bottom punching with big диамертом and a sharp edge on an exit of an air stream (and an exit проникших particles outside). Elimination of the lacks, inherent mode псевдоожижения zones of cooling 4 and tubular газораспределителем on a prototype, allows to lower incompleteness of heat exchange between air and arriving on cooling известью in such a manner that the difference of temperatures of a boiling layer of a zone of cooling 4 and air going on burning in a zone of roasting 1 from надслоевого of space of a zone of cooling 4, will decrease with 50-100 to 40-95°С. The temperature of air arriving on burning of fuel with 360 - 280 to 370 - 4000С Besides, will increase, that also reduces fuel losses to process of roasting and thermal losses of the furnace as a whole. The offered invention with reference to Open Society "Motor Sich" conditions will allow to provide the technological indicators presented in the table.
Quality to exhaust, estimated on a total share оксидов calcium and magnesium, accordingly, will increase by 2,0-2,5 %. Also on 5-7 % the between-repairs period of operation of the furnace will increase. With reference to conditions of the furnace of Open Society "Motor Sich" performance of an aperture of the top punching with a diameter 10,0 mm is defined by necessity of a choice of diameter of an aperture of the bottom punching equal 12,2 - 17,3 ÷ 20,0 - 30,0, depending on the chosen conditions псевдоожижения and физико – chemical properties of processed limestone and to exhaust. THE FORMULA OF USEFUL MODEL
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