SU618613A1

SU618613A1 - Dryer for pulverulent materials

Info

Publication number: SU618613A1
Application number: SU762396713A
Authority: SU
Inventors: Леонид Владимирович Николайчик; Александр Исаакович Любошиц; Владимир Петрович Попков; Макс Борисович Кац
Original assignee: Ордена Трудового Красного Знамени Институт Тепло- И Массообмена Им. А.В.Лыкова Ан Белорусской Сср
Priority date: 1976-08-16
Filing date: 1976-08-16
Publication date: 1978-08-05

Description

Изобретение относитс к сушильной технике и может быть использовано в пищевой, химической промышленности и в сельском хоз йстве, например, дл сушки зерна.The invention relates to a drying technique and can be used in the food, chemical industry and in agriculture, for example, for drying grain.

Известны рециркул ционные сушилки дл дисперсных материалов, содержашие цилиндрическую шахту с поперечно размещенными в ней полыми стержн ми, подключенными с одного конца к источнику теплоносител , а с другого - к отвод шему газоходу , в котором установлен кожухотрубный теплообменник 1.Recirculating dryers for dispersed materials are known that contain a cylindrical shaft with transversely placed hollow rods connected from one end to a source of heat transfer fluid and from the other to a discharge gas duct in which a shell-and-tube heat exchanger 1 is installed.

Однако, так как в этих сушилках полые стержни подключены к источнику теплоносител , имеющего температуру 700-800°С, то высушиваемый материал, попада на стержни, подвергаетс высокотемпературному воздействию, и его качество ухудшаетс . Кроме того, в данной сушилке с целью утилизации тепла отработавших топочных газов в отвод щем газоходе установлен кожухотрубный теплбобменник, это приводит к значительному увеличению размеров сушилки и усложн ет ее монтаж.However, since in these dryers the hollow rods are connected to a source of heat carrier having a temperature of 700-800 ° C, the material to be dried, falling on the rods, is subjected to high-temperature exposure, and its quality deteriorates. In addition, a shell and tube heat exchanger is installed in this dryer for the purpose of utilizing the heat of exhaust flue gases in the exhaust gas duct, which leads to a significant increase in the size of the dryer and complicates its installation.

Известны также терморадиационные сушилки дл дисперсных материалов, содержашие щахту, снабженную снаружи рекунеративным теплообменником с воздушнымThermoradiation dryers for dispersed materials are also known, which contain a shag, equipped on the outside with a regenerative

каналом и каналом дл продуктов сгорани , выполненными по спирали. Внутренн поверхность шахты снабжена радиационными нанел ми с горелками, к которым и подводитс нагретый в теплообменнике возДух .a channel and a channel for the products of combustion, made in a spiral. The inner surface of the shaft is equipped with radiation nanoel with burners, to which the air heated in the heat exchanger is supplied.

По конструктивным признакам и техническому существу эти сушилки наиболее близки к предлагаемой.By design features and technical essence, these dryers are closest to the offer.

Радиационна передача тепла не обеспечивает равномерность нагрева высушиваемого материала и может ухудшить его качество , например при сушке зерна.Radiation heat transfer does not ensure uniform heating of the material being dried and may deteriorate its quality, for example, when drying grain.

Цель изобретени - повышение качества сушки.The purpose of the invention is to improve the quality of drying.

Claims

This is achieved by the fact that the dryer additionally contains two sections of heat pipes, and the heat exchanger is made in the form of two coaxially arranged cylinders, and its air channel is placed between them and connected below to the internal cavity of the shaft, and the heat pipes pass through the wall of the latter and through the internal cylinder of the heat exchanger , and the evaporation zones of the tubes of both sections are located in the channel for the combustion products, and the sensation zones are respectively inside the air channel and in the bottom of the shaft. FIG. 1 schematically shows a dryer; FIG. 2 shows a section A-A of FIG. 1. The dryer contains mine 1, I have a loading 2 and unloading. 3 devices and equipped with a recuperative heat exchanger, made in the form of coaxially arranged cylinders 4 and 5 with an air channel 6 and a channel 7 for flue gases (combustion products). The air channel 6 with the help of a tangentially installed nozzle 8 is connected to a source of cold air (not shown in the drawings) and connected from below to the inner cavity 9 of the shaft 1, which has a nozzle 10 for exhaust air. Channel 7 for flue gases is connected to the bottom by means of pipe 11 with a furnace (not shown in the drawings) and by means of pipe 12 with atmosphere. A section of heat pipes 13 is drawn through the wall of the shaft 1, and a second section of heat pipes 14 passes through the inner cylinder 4. Heat pipes 13 and 14 can be arranged in a spiral. The evaporation zones of pipes 13 and 14 are placed in the channel 7 for flue gases, the condensation zones of the pipes 13 are located in the inner cavity 9 of the shaft 1, and the condensation zones of the pipes 14 are in the air duct 6. The proposed dryer works as follows. The wet material from the loading device 2 is fed into the internal cavity 9 of the shakht 1, where the material enters the heat pipes 13, is distributed evenly over the cross section of the shaft 1 and is heated by conductive heat supply. The cold air is supplied tangentially through the nozzle 8 into the air channel 6, in which the condensation zones of the heat pipes 14 are located, which also play the role of guide spiral inserts. Then the heated air (the agent agent) is fed into the internal cavity 9 of the dacha 1 towards the falling layer of the material being dried, and thus its convective heating is also carried out. The flue gases through the pipe 11 is fed into the channel 7 countercurrent air. In this channel 7 there are located evaporator zones of heat pipes 13 and 14, which serve to transfer heat to channel 6 and to cavity 9, and also play the role of spiral inserts. Spent agent waste and flue gases are emitted into the atmosphere through a pipe of 10 m and 12 m respectively. The design of the regenerative substance allows to significantly intensify heat transfer from both the flue gases and the air, by increasing the actual heat exchange surface, and at the same time reduce the dimensions of the dryer. The use of heat pipes placed by the hot end in the annular channel 7 for flue gases to preheat the air (drying agent) in channel 6 and to transfer heat to the material being dried makes it possible to lower the temperature of the flue gases leaving the dryer and therefore increase it thermal efficiency. In addition, efficient organization of heat exchange in annular gaps allows reducing the consumption of high-temperature heat transfer media, which causes a corresponding decrease in heat loss with gases leaving the dryer. DETAILED DESCRIPTION OF THE INVENTION Dryer for dispersed materials comprising a shaft provided externally with a regenerative heat exchanger with an air channel and a channel for combustion products, characterized in that, in order to improve the quality of drying, the dryer further comprises two sections of heat pipes and the heat exchanger is coaxial cylinders, and its air channel is placed between them and connected from below to the internal cavity of the shaft, and the heat pipes are led through the wall of the latter and through the internal cylinder The exchangers, and the evaporation zones of the tubes of both sections are located in the channel for the combustion products, and the condensation zones, respectively, inside the air channel and in the cavity. Sources of information taken into account during the examination: 1. Application No. 2316645, cl. F 26 D 17/10, 1975, according to which a decision was made to issue an author's certificate.

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