KR101901940B1 - Sludge drying device reusing vapor heat - Google Patents

Abstract

The present invention provides a steam heat recycling sludge drying apparatus (1) for drying steam contained in various kinds of sludge in a vacuum to be used for drying the sludge, comprising a sludge feed pipe A drying drum 2 provided with a sludge agitating and conveying means 23 on the inner side thereof with a discharge pipe 22 and a heating means 3 configured to indirectly heat sludge in the drying drum 2, A vacuum pump 5 installed on the side of the condenser 4 for forcedly sucking water vapor inside the drying drum 2 into the condenser 4 and a drying drum 2 for condensing the evaporated water vapor, A vacuum valve 6 provided in each of the inlet pipe 21 and the discharge pipe 22 so as to keep the inside of the condenser 4 in a vacuum state and water vapor drawn into the condenser 4 through the drying drum 2 and the condenser 4, (7) configured to be pressurized within the chamber (4) And a condensing water recovery pipe 8 connected between the condenser 4 and the heating means 3 so that the condensed water vapor heated and evaporated in the sludge is forced and conveyed to the condenser 4, The sludge can be dried and dewatered more quickly by supplying the condensed water and the latent heat to the heating means 3 while heating the hot water while vacuuming the interior of the sludge, You can expect.

Description

[0001] Sludge drying device reusing vapor heat [

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying apparatus for waste sludge, more specifically, to dry a large amount of moisture contained in organic sludge such as sewage sludge, industrial sludge and food sludge, And more particularly, to a steam heat recycling sludge drying apparatus which uses heat of water vapor to dry the sludge, thereby improving energy efficiency.

Generally, sludge is also called sludge, and is produced in the process of disposing sediments or industrial wastes or food wastes generated in the sewage treatment or water purification process, and the sludge has a water content of 80 to 90% And the moisture contained in a large amount is mechanically dried and dehydrated so as to be separated into solid matter (solid matter).

Conventionally, a drying device for drying and dewatering various kinds of waste sludge is designed to dry the moisture contained in the sludge by applying heat from the outside only. In order to dry and dehydrate a large amount of water contained in the sludge, It is difficult to obtain landfill or landfill by dehydrating most of the sludge after anaerobic treatment because it is difficult to recycle the sludge by drying and dehydrating it. It has been disadvantageous in terms of environment by disposing it by means of incineration or the like.

As described above, devices for drying and dewatering sludge having a high water content have existed. As known sludge drying and dewatering devices, there are known sludge drying and dewatering devices as disclosed in Korean Utility Model No. 187805 (published on July 15, 2000) A vacuum drying dehydrator provided with a heating plate provided with stirring means for stirring the supplied sludge and a sludge discharge valve for discharging the dried sludge, and a heating plate for applying heat to the sludge, and a condenser for condensing the steam generated in the vacuum drying dehydrator, And a vacuum pump for evacuating the interior of the vacuum drying and dehydrator so that the temperature of the vacuum drying dehydrator is increased by generating a temperature difference between the heat transfer surface and the heat transfer surface, has been developed, and a sludge vacuum drying and dewatering device has been developed As in No. 853910 (published Aug. 25, 2008), a conveying screw A sludge vacuum drying apparatus was developed in which the steam generated by heating the sludge conveyed by the drum by the heating means was cooled by the evaporation heat of the refrigerant in the evaporator and liquefied and the inside of the drum was reduced to atmospheric pressure or less by using a vacuum pump And the inside of the drying tank is vacuum-depressurized through a vacuum port and a vacuum pump while supplying high-temperature steam to the drying tank as described in Korean Patent Laid-Open Publication No. 12844 (published on Feb. 13, 2012) A vacuum decompression sludge drying device has been developed which can lower the evaporation temperature of water contained in the sludge by lowering the drying speed of the sludge to greatly reduce the operation cost. (= Depressurized state) so that the water inside the sludge is treated with water at atmospheric pressure (= Decompression) drying and dewatering devices for waste sludge have existed as technologies capable of evaporating at a temperature of 100 ° C or less, which is a breaking temperature, to significantly reduce the energy consumption rate used for rapid drying and drying Such conventional sludge vacuum drying and dewatering apparatuses can heat the sludge under vacuum to vaporize at a low temperature to reduce the energy consumption rate. However, in order to dry and dehydrate the continuously supplied sludge, continuous heating is required, Because of the continuous supply of steam or hot water for this, the energy consumption was also significantly higher.

KR 20-0187805 Y1 2000. 7. 15. KR 10-0853910 B1 2008. 8. 25. KR 10-2012-0012844A Feb. 13, 2012.

Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art and to develop a new technology to more efficiently dry the waste sludge. The present invention is to provide a vacuum drying and dewatering apparatus for a conventional waste sludge, (= Depressurized state), and the heat of steam generated at this time is supplied to the heating means of the sludge to be reused for heating the continuously supplied sludge, whereby the moisture of the function sludge having a high water content can be quickly and smoothly And the energy consumption rate of the heating means can be remarkably reduced due to the reuse of the steam heat while being able to remove the steam sludge from the sludge drying apparatus.

In addition, according to the present invention, there is a further proposal to further enhance the energy efficiency by supplying steam to the heating means by doubling the heat of the steam by compressing the steam to a high pressure without supplying the heat of the steam directly to the heating means .

Further, the structure of the heat exchange jacket between the material of the drying drum and the heating means and the drying drum is improved so that the heat conduction can be smoothly performed by indirect heat of the heating means, and the thermal efficiency can be further improved I would like to propose.

According to the present invention, there is provided a device for drying a steam heat recycling sludge according to the present invention, wherein the steam heat recycling sludge drying device of the present invention comprises a sludge- And the sludge in the drying drum is indirectly passed through the drying drum while the hot water is passed to the outside of the drying drum. A condenser for condensing the water vapor evaporated in the sludge heated by the heating means and condensing the condensed water into the condenser; a vacuum pump installed on the side of the condenser for forcedly sucking the steam inside the drying drum into the condenser; The vacuum pump is installed in the drying drum And a vacuum valve provided to prevent the outside air from being sucked into the drying drum so as to maintain the vacuum state. The drying drum and the evaporator are evaporated in the drying drum by the heating means and heated by the vacuum pump to the condenser And a condensing water recovery pipe connected between the condenser and the heating means is provided with a pressurizing means configured to pressurize the sucked steam in the condenser.

According to the concrete means for solving the above-mentioned problems, the steam heat recycling sludge drying apparatus of the present invention is characterized in that the water sludge having high water content is heated and heated by means of indirect heat of hot water while agitating and conveying water- The sludge in the drying drum is forced to pressurize and pressurize steam evaporated from the sludge in the drying drum to the condenser so that the steam is vacuumed in the drying drum while the steam is liquefied in the condenser and the latent heat generated in the condenser is transferred to the liquefied sludge By supplying the heated sludge together with moisture to the heating means to heat the hot water of the heating means, the water sludge is heated in the vacuum state to evaporate moisture at a lower temperature than the atmospheric pressure, and the heat of the steam generated in the sludge is heated It is used for heating so that the moisture contained in the sludge is more quickly It is possible to dry and dehydrate very efficiently, thereby generating a large amount of water vapor in a short time, thereby reducing the heating time. Therefore, energy consumption is reduced and a large amount of steam heat is reused for heating the sludge, To maximize the effect of the present invention.

A heat exchange jacket is installed between the drying drum and the heating means, which is made of aluminum 393 material having a good thermal conductivity, so as to widen the heat exchange area. By heating the drying jacket so as to dry and dewater in a short time, The annular heating water tank into which the hot water is introduced is raised to the side of the drying drum and the opposite side is inclined to be inclined so that hot water in the heating water tank is rotated by the convection phenomenon and hot water having a high temperature is supplied to the heat exchange jacket, And that the expected effects are the same.

1 is a perspective view of a sludge drying apparatus according to an embodiment of the present invention;
Fig. 2 is a front view of Fig. 1
Fig. 3 is a perspective view of a three-dimensional drawing showing the separated state of the drying drum and the heat-
Figure 4 is a schematic diagram of the present invention
5 is a block diagram showing the operation of the present invention

The present invention relates to a drying apparatus for drying and dehydrating moisture contained in a large amount of organic sludge such as sewage sludge, industrial sludge and food sludge, and more particularly, to a method of drying a sludge by heating heat of steam generated during drying and dewatering of sludge The present invention provides a steam heat recycling sludge drying apparatus capable of maximizing the energy efficiency by making it possible to reuse the steam recycle sludge drying apparatus, which will be described in more detail below with reference to the drawings.

As shown in FIGS. 1 and 2, the steam heat recycling sludge drying apparatus 1 of the present invention includes a drying drum 2 in which a water sludge containing a large amount of moisture is mixed and stirred, a drying drum 2, A heating means 3 for indirectly heating the sludge therein and a condenser 4 for conveying the steam generated in the sludge treatment by the heating means 3.

In the drying drum 2, a discharge pipe 21 through which a sludge for drying is introduced into both sides and a discharge pipe 22 through which a solid sludge dried and dewatered by the heating means 3 are discharged are connected And the inside of the drying drum 2 is filled with a syringe which is inserted into a rotary shaft 24 interlocked by a driving motor 25 and an interlocking means 26 as shown in FIG. A scraper 231 (scraper) for preventing the sludge from adhering to the inner wall of the drying drum 2 together with a rod or screw and disk-shaped stirring and conveying means 23 for conveying the sludge to the discharge pipe 22, And the scraper 231 may be installed in the stirring and conveying means 23 according to the shape of the scraper 231. The end of the discharge pipe 22 is equipped with a reservoir 221 through which the solid sludge dried and dewatered with moisture is transferred and stored Respectively.

The heating means 3 is constructed such that hot water heated by high temperature steam is indirectly heated by passing the drying sludge inside the drying drum 2 while passing through the outside of the drying drum 2, An annular heating water tank 31 having a height h higher than the lower side of the drying drum 2 is provided so as to be inclined upward toward the drying drum 2 as shown in FIG. The circulation pump 32 may be provided to smoothly circulate hot water in the heating water tank 31 when the circulation of the hot water due to the convection phenomenon is slow.

At this time, hot water of a relatively high temperature is raised to the upper side of the drying drum 2 by the temperature difference of hot water in the heating water tank 31, and the hot water in the inside of the heating water tank 31 A steam supply pipe 33 connected to supply the high temperature steam is provided and a hot water discharge pipe 311 is connected to one side of the lower part of the heating water tank 31 so as to discharge hot water therein.

The condenser 4 of the present invention is constructed such that water vapor evaporated from the sludge in the drying drum 2 heated by the heating means 3 is conveyed on the steam conveying pipe 41 to be condensed into water, The vacuum pump 5 is installed on the side of the drying drum 2 so that water vapor in the drying drum 2 is forcibly sucked into the condenser 4. The inside of the drying drum 2 is kept vacuumed by the vacuum pump 5 And the sludge is introduced into and discharged from the drying drum 2 without the outside air being sucked into the drying drum 2 to the discharge pipe 22 through which the sludge is introduced and the discharge pipe 22 through which the sludge is discharged, A vacuum valve 6 is provided.

1, the drying steam is evaporated in the drying drum 2 by the heating means 3 and the water vapor drawn into the condenser 4 by the vacuum pump 5 is introduced between the drying drum 2 and the condenser 4, A pressing device 7 such as a fan or an air compressor is interposed between the vacuum pump 5 and the condenser 4 so as to be pressurized in the condenser 4. In this embodiment, The inside of the condenser 4 is pressurized to 60 kPa when the pressure inside the drying drum 2 by the vacuum valves 6 is 40 kPa.

The condensed water liquefied in the condenser 4 is pressurized by the pressurizing means 7 so that the temperature is raised to the latent heat generated by the liquefaction of the water vapor introduced from the drying drum 2 to the heating means 3 A condensate return pipe 8 connected between the condenser 4 and the heating water tank 31 of the heating means 3 is provided for recycling and the condensate return pipe 8 is provided with a vacuum pump 5, The ultraviolet sterilizing lamp 81 is installed in the condensate return pipe 8 so that the condensed water is forcibly supplied to the heating water tank 31 when the internal pressure of the condenser 4 is excessively increased to heat the hot water in the heating water tank 31. [ So that the condensed water can be sterilized and supplied to the heating water tank 31.

1 and 3, a heat exchange jacket 9 is provided outside the drying drum 2 so that the hot water of the heating means 3 heats the drying drum 2 as a whole. Such a heat exchange jacket 9 is shown in FIG. 3 An outer housing 92 coupled to the outside of the drying drum 2 and configured to form a hot water passage 93 through which the hot water of the heating means 3 flows into the inside of the drying drum 2, And a heat exchange fin 94 protruding perpendicularly to the traveling direction of hot water passing through the hot water passage 93 toward the hot water passage 93 inside the hot water passage 92.

4, the driving motor 25 of the stirring / conveying means 23 in the drying drum 2 is driven by the motor / The hot water is always heated to a constant temperature through the temperature sensor 11 in the heating water tank 31 of the heating means 3 so as to control the steam supply valve 34 of the steam supply pipe 33, And a temperature sensor 11 and a pressure sensor (not shown) in the drying drum 2 when the vacuum pump 5 and the vacuum valve 6 are electrically connected to the microcomputer 10, The microcomputer 10 controls the temperature and the pressure of the inside of the drying drum 2 by connecting the circulation pump 32 inside the heating water tank 31 and the ultraviolet ray And is also electrically connected to the sterilizing lamp 81 by wiring.

As shown in FIG. 5, the water vapor recycling sludge drying apparatus 1 of the present invention having the above-described structure is formed by injecting the sludge into the drying drum 2, drying and dehydrating the sludge by indirect heat of the heating means 3, Is discharged to the reservoir 221, and its effect will be more specifically described below.

The sludge having a water content of 80 to 90% is introduced into the drying drum 2 through the inlet pipe 21 and the rotating shaft 24 provided in the drying drum 2 by the driving motor 25 and the interlocking means 26, And indirectly heats the functional sludge in the drying drum 2 by the hot water which is the heating means 3 passing through the outside of the drying drum 2 at this time by stirring and conveying by the stirring and conveying means 23, When the sludge is fixed to the inner wall of the drying drum 2 by the heating means 3, it is prevented by the scraper 231.

As the sludge inside the drying drum 2 is heated by the indirect heat of the heating means 3 as described above, the inside of the drying drum 2 is vacuumed and decompressed so that the sludge can be heated quickly at a temperature lower than that of the sludge, The water vapor evaporated from the sludge by the means 3 is forcibly sucked into the condenser 4 and the vacuum pump 5 installed on the side of the condenser 4 is operated so that the interior of the drying drum 2 is evacuated, 21 and the vacuum valve 6 of the discharge pipe 22. The inside of the drying drum 2 is depressurized to 40 kPa by the vacuum pump 5 and the moisture of the sludge is vaporized at 80 DEG C, (= Water) was vaporized at 100 캜, but in the vacuum state as in the present invention, vaporization occurs at a lower temperature of 80 캜.

In addition, the water vapor of the sludge vaporized at 80 캜 is conveyed to the condenser 4 by the vacuum pump 5 and is supplied to the condenser 4 by the pressure means 7 interposed between the drying drum 2 and the condenser 4, The condensed water vapor is condensed in the condenser 4 and the liquefaction is accelerated by the pressing force of the pressurizing means 7 and the latent heat of the steam generated at this time causes the outside of the condenser 4 to be insulated, Is recovered to the heating water tank 31 through the condenser 4 and the condensate return pipe 8 connected to the heating water tank 31 of the heating means 3 by the vacuum pump 5, The hot water in the heating water tank 31 is heated.

As the hot water in the heating water tank 31 is heated to 84 ° C, the steam supply valve of the steam supply pipe 33 is opened to further warm the hot water to 85 ° C to indirectly heat the sludge of the drying drum 2.

As described above, the hot water in the heating water tank 31 is first heated to 85 ° C with high temperature steam, or the steam heat of the sludge is recycled to heat the hot water to 84 ° C while heating the hot water to 85 ° C, The hot water in the heating water tank 31 of the heating means 3 is supplied to the drying drum 2 to heat the sludge inside the drying drum 2 by heating the hot water in the drying drum 2 The heat exchange jacket 9 is installed so as to flow around the outside of the heat exchanger.

The heat exchange jacket 9 is formed by protruding several heat exchange fins 94 on the outside of the drying drum 2 so that hot water passes through the hot water passage 93 between the outer housing 92 coupled with the drying drum 2 The heat exchange area can be maximized to heat the sludge in the drying drum 2 at a temperature of 80 DEG C by hot water at 85 DEG C even if the heat is heated by the indirect heat, and the drying drum 2 and the drying drum 2 The heat exchange efficiency of the heat exchange fin 94 can be further improved by using aluminum 393 having high durability and extremely high thermal conductivity.

Conversely, both sides of the drying drum 2, the outer wall of the heating water tank 31 of the heating means 3, the outer wall of the condenser 4 and the steam transport pipe 41, and the outer wall of the condensate return pipe 8 are It is constructed so as to have a heat insulating structure or a double heat insulating structure so that internal heat is not emitted.

The hot water of the heating means 3 is heated inside the drying drum 2 in a vacuum state when the sludge inside the drying drum 2 is heated by the above constitution and operation, The steam is heated by the indirect heat of the hot water in the vacuum state and the steam generated in the drying drum 2 is forcibly sucked into the condenser 4 by the vacuum pump 5, The condensed water whose temperature has been raised by the latent heat is heated by the condensed water return pipe 8 to heat the hot water of the heating means 3 and the hot water in the heated water tank 31 is heated by the condenser 4, The amount of steam supplied to raise the temperature can be significantly reduced, saving energy overall.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, it should be understood that various changes and modifications may be made without departing from the scope of the present invention. It will be understood that various modifications may be made without departing from the spirit and scope of the invention, and thus the scope of protection of the present invention is not limited to the embodiments described above but may be modified and changed without departing from the scope of the following claims and their equivalents The scope should be recognized.

1: Drying device
2: drying drum, 21: inlet pipe, 22: discharge pipe, 221: storage tank, 23: agitation conveying means, 231: scraper, 24: rotating shaft, 25: driving motor, 26:
3: heating means 31: heating water tank 311: hot water discharge pipe 32: circulation pump 33: steam supply pipe 34:
4: condenser, 41: steam transmission line
5: Vacuum pump
6: Vacuum valve
7: Pressurizing means
8: condensate return pipe, 81: ultraviolet sterilization lamp
9: heat exchange jacket, 92: outer housing, 93: hot water passage, 94: heat exchange pin
10: Microcomputer, 11: Temperature sensor, 12: Pressure sensor

Claims (3)

A supply pipe 21 through which sludge for drying is introduced to both sides and a discharge pipe 22 through which dried sludge is discharged are connected to each other and a stirring and conveying means 23 for stirring and conveying the introduced sludge is installed and rotated A drum (2);
A heating means (3) configured to indirectly heat the sludge inside the drying drum (2) while hot water passes to the outside of the drying drum (2);
A condenser (4) configured to transfer the water vapor evaporated in the sludge heated by the heating means (3) to condense into water;
A vacuum pump 5 installed on the side of the condenser 4 for forcedly sucking the water vapor inside the drying drum 2 into the condenser 4;
A vacuum valve 6 installed so that outside air is not sucked into the drying drum 2 through the inlet pipe 21 and the discharge pipe 22 so that the interior of the drying drum 2 is maintained in a vacuum state by the vacuum pump 5;
Vapor in the condenser 4 is evaporated in the drying drum 2 by the heating means 3 and then sucked into the condenser 4 by the vacuum pump 5 through the drying drum 2 and the condenser 4, Pressure means (7) configured to be pressed;
A condensate return pipe (8) connected between the condenser (4) and the heating means (3);
≪ / RTI >
The heating means 3 is provided with an annular heating water tank 31 configured to be inclined upward toward the drying drum 2 so as to be heated by the convection phenomenon, And a steam supply pipe (33) connected to heat the hot water of the steam heat recycling sludge.
The method of claim 1,
An outer housing 92 coupled to the outside of the drying drum 2 and configured to form a hot water passage 93 through which the hot water of the heating means 3 flows into the inside of the drying drum 2, (9) consisting of a heat exchange fin (94) formed so as to protrude perpendicularly to the traveling direction of the hot water passing through the hot water passage (93) toward the hot water passage (93) inside the hot water passage (92).
Wherein the sludge drying apparatus further comprises a water vapor recycling sludge drying apparatus.
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