KR20100113947A - Low-energy drying system for preheating sludge using exhaust gas of dryer - Google Patents

Abstract

PURPOSE: A low-energy drying system for preheating sludge using exhaust gas of a dryer is provided to reduce the heat taken for drying by increasing the temperature of the sludge put into a dryer. CONSTITUTION: A low-energy drying system for preheating sludge using exhaust gas of a dryer includes a hopper(11), a supply feeder(12), a drying furnace(14) and a deodorizing device(16). The hopper temporally stores high function sludge, and the supply feeder supplies the sludge stored at the hopper at a certain rate. The drying furnace dries the sludge by supplying high temperature transfer gas to the sludge, and the deodorizing device removes the bad smell of the discharged gas.

Description

LOW-ENERGY DRYING SYSTEM FOR PREHEATING SLUDGE USING EXHAUST GAS OF DRYER}

The present invention relates to a low-energy drying system for preheating sludge using exhaust gas from a drying furnace, and more specifically, high-function sludge is introduced into a drying furnace through a sludge preheater, and the hot gas evaporated from the drying furnace is a sludge preheater. The present invention relates to a low-energy drying system capable of reducing the amount of heat required for drying by increasing the temperature of the sludge which is introduced into the drying furnace by heat exchange in the sludge preheater.

In general, high sludge wastewater containing 80% or more of water contains a significant increase in the amount generated along with organic / inorganic chemical wastes in sewage / wastewater treatment processes, dyeing, steelmaking, and chemical processes. have. These wastes are the main contaminants of water and soil, and their effective management is very important.

Most of these sludge wastes have been relied on landfills. Recently, various research and development efforts have been made in Korea and abroad to recycle or recycle these wastes.In developed countries, a large part of them are composted after drying and construction materials after incineration melting. It has been put to practical use, and various studies have been made in Korea.

The structure of the conventional drying apparatus 1 for drying the sludge has a supply unit 2 consisting of a hopper for storing sludge and a feed feeder for supplying a predetermined amount from the hopper, as shown in FIG. 9, and the supplied sludge at a high temperature. A drying furnace (3) contacting and drying the gas in contact with the gas, a condenser (4) condensing and removing moisture contained in the exhaust gas from the drying furnace, and odors and harmful components of the exhaust gas passing through the condenser. It is configured to include a post-processing device to remove.

Since the drying furnace discharges the exhaust gas at a high temperature, energy loss is generated as much as the discharged amount. Therefore, in order to minimize energy loss, the operation temperature of the drying furnace is set to 100 ° C. or lower.

However, since the operation time at such a temperature increases the drying time, the throughput of the drying furnace is lowered, and the amount of heat required per sludge treatment capacity is large. Therefore, the efficiency of the drying apparatus may be increased by utilizing the exhaust gas. There is a need for research on possible devices.

Accordingly, the present invention has been made to solve the above problems, the high-temperature sludge introduced into the drying furnace and the high-temperature exhaust gas discharged from the drying furnace is heat-exchanged so that the high-function sludge is heated to a high temperature before being introduced into the drying furnace It is an object of the present invention to provide a device for rapid drying in a drying furnace.

Low energy drying system for preheating the sludge by using the exhaust gas of the drying furnace of the present invention for solving the above problems,

A hopper for temporarily storing high-function sludge, a feed feeder supplying the sludge stored in the hopper by a predetermined amount, a drying furnace for supplying a high temperature feed gas to the sludge supplied by the feed feeder to dry the sludge, and in the drying furnace In a drying system including a deodorizer for removing the odor of the discharged exhaust gas, a sludge preheater is installed between the feed feeder and the drying furnace, and the sludge discharged from the feed feeder is supplied to the drying furnace through the sludge preheater. In order to reduce the amount of drying heat supplied to the drying furnace by the heat exchange between the sludge introduced into the drying furnace and the hot exhaust gas discharged from the drying furnace, the hot exhaust gas discharged from the drying furnace passes through the sludge preheater and is then subjected to post-treatment. It is composed.

As described in detail above, a low energy drying system for preheating sludge using exhaust gas of the drying furnace of the present invention,

The high function sludge is introduced into the drying furnace through the sludge preheater, and the hot gas evaporated from the drying furnace is discharged through the sludge preheater, thereby exchanging heat in the sludge preheater to increase the temperature of the sludge introduced into the drying furnace. It has the effect of reducing calories.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a process diagram schematically showing a low energy drying system for preheating sludge using exhaust gas from a drying furnace according to the present invention, FIG. 2 is a cross-sectional view showing a sludge preheater according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the sludge preheater mounted on the sludge preheater, and FIGS. 4 to 7 are schematic cross-sectional views of the sludge preheater according to another embodiment of the present invention.

As shown in FIG. 1, the drying system 10 according to the present invention includes a hopper 11 and a feed feeder 12 to quantitatively supply high-density sludge temporarily stored in the hopper to the drying furnace 14.

The sludge supplied by the feed feeder 12 is supplied to the sludge preheater 13 before being introduced into the drying furnace, and is preheated. The preheated sludge is supplied to the drying furnace 14 and is a high temperature transfer gas in the drying furnace. Drying is achieved by supplying steam to evaporate the water in the sludge.

The sludge residue dried in the drying furnace 14 is incinerated, landfilled or recycled by discharge, and the hot discharge gas containing water passes through the sludge preheater 13 and is introduced into the drying furnace. After the heat exchange is made and the odor or harmful components are removed through the deodorizer 16 is discharged.

Since the high temperature exhaust gas contains a large amount of water, it is preferable to remove the water (steam) contained in the exhaust gas by using the gas-liquid separator 17 in the process of discharge.

In addition, the transfer gas for heating the sludge of the drying furnace 14 may be used in addition to the above-described steam, high-temperature air, in the case of using the steam because the moisture content contained in the exhaust gas of the drying furnace is essentially condenser 15 It is preferable to further install) to remove the moisture of the exhaust gas. Of course, the condenser may be installed to remove moisture even when hot air is used as the transport gas.

In the system 10 as described above, the sludge preheater 13 for heat-exchanging high-temperature sludge introduced into the drying furnace 14 and the high-temperature exhaust gas discharged from the drying furnace is composed of a tubular body as shown in FIG. 2. It consists of a main body tube 20 and a sludge feed branch pipe 30 installed in the main body tube.

The main body tube 20 forms a gas inlet 21 and a gas outlet 22 on the side to allow the high temperature exhaust gas discharged from the drying furnace 14 to flow into the body tube through the gas inlet 21. To be discharged to the outside through the gas outlet 22, a post-treatment process such as condensation or deodorization is performed.

The sludge feed branch pipe 30 is formed with a small diameter so that the sludge supplied from the feed feeder is preheated by the hot exhaust gas distributed into the main body pipe while being branched to the plurality of sludge feed branch pipes 30. That is, the sludge conveyance branch pipe 30 is composed of a plurality of small diameters to increase the contact area between the discharge gas and the sludge, so that each of the sludge transfer branch pipes to be spaced uniformly to the space spaced between the sludge conveyance pipe The heat transfer efficiency was increased by smoothly flowing the high temperature exhaust gas.

Therefore, the sludge supply pipe 80 for supplying the sludge from the feed feeder to the sludge preheater 13 has an extended portion 81 at the end contacting the sludge preheater 13, as shown in FIG. It is desirable to correspond to an increased sludge preheater.

In addition, both ends of the sludge preheater 13 is provided with a blocking plate 40 to prevent the exhaust gas supplied into the main body tube 20 to be discharged through both ends of the main body tube. The blocking plate 40 is installed at both ends of the sludge preheater to seal the space between the outer circumferential surface of the sludge feed-in pipe 30 and the inner circumferential surface of the main body pipe 20 so that the high-temperature exhaust gas supplied to the inner space of the main body pipe is Prevent spills. In addition, the blocking plate 40 to prevent the sludge supplied through the sludge supply pipe 80 to enter the space between the main body pipe and the sludge feed branch pipe and to be introduced only into the sludge feed branch pipe (30).

In addition, condensed water is generated by partial condensation of water vapor contained in the hot exhaust gas by heat exchange between the hot exhaust gas and the sludge, and the condensate is discharged through the gas outlet 22 formed in the main body tube. Therefore, the gas discharge port is preferably to be formed on the inner bottom of the body tube.

The sludge preheater 13 is provided with a plurality of baffles 50, as shown in Figure 3 so as to extend the movement path of the exhaust gas supplied into the main body tube. That is, the baffle 50 is installed in a zigzag form so that the exhaust gas moved from the gas inlet 21 to the gas outlet 22 is moved to the zigzag to increase the contact efficiency with the main body tube 20.

On the other hand, the pipe of the sludge preheater 13 installed between the feed feeder 12 and the drying furnace 14 may be bent pipe according to the installation position of the two devices. Therefore, the installation state of the sludge preheater of the present invention can also be varied depending on the bent portion.

Figure 4 is a schematic diagram showing a sludge preheater according to another embodiment of the present invention, by using the sludge preheater 13 shown in Figure 2 by installing a separate curved pipe 60 and extension pipe 70 to preheat the sludge The drying furnace 14 was to be fed.

As shown, the high function sludge is supplied to the lower portion of the sludge preheater 13 so as to be transported upward, so that the sludge is introduced into the upper surface of the drying furnace 14. At this time, the sludge supply pipe 80 is coupled to the lower bottom of the main body pipe 20 so that the high-function sludge supplied from the feed feeder is transferred through the sludge transfer branch pipe 30 installed inside the main body pipe. In this case, the sludge supply pipe 80 forms an end coupled with the main body pipe as an expansion part 81 so that the sludge to be transported is branched into each sludge feed branch pipe, and a blocking plate 40 is provided at the end of the main body pipe. The formed sludge is prevented from flowing into the space between the main tube 20 and the sludge transfer branch pipe 30 so that the sludge is transferred only through the sludge transfer branch pipe 30. In addition, the blocking plate 40 is also installed at the upper end of the main body tube 20 to prevent the sludge discharged through the sludge transfer branch pipe from entering the inner space of the main body tube.

In addition, the upper end of the body pipe 20 is coupled to one end of the curved pipe 60 containing the sludge transport pipe 90 so that the conveying direction of the sludge is switched, the extension pipe 70 to the other end of the curved pipe 60 Combine one side end of the, and the other end of the extension tube communicates with the drying furnace 14 to be supplied to the drying furnace preheated sludge passed through the main body tube (20). At this time, the sludge conveying pipe (90) installed inside the curved pipe (60) and the extension pipe (70) is connected to the sludge conveyance pipe (30) by being coupled to the main pipe (20) with an end portion having an extension (91) formed therein. The sludge conveyed through the sludge feed branch pipe is joined while passing through the expansion portion 91 of the sludge conveying pipe to make the transfer.

In addition, the curved pipe 60 and the extension pipe 70 allow the discharge gas of the drying furnace to pass through the space between the sludge transfer pipe 90 piped therein so as to prevent the sludge temperature during transportation from being lowered. That is, the hollow part inside the curved tube 60 and the extension tube 70 is in communication with each other, but is fitted between the sludge feed tube 90 and the extension tube 70 by mounting a blocking plate 40 at the end of the extension tube 70 coupled to the drying furnace By enclosing the space, the hot exhaust gas supplied into the space between the sludge conveying pipe and the extension pipe was prevented from flowing out.

An extension pipe gas inlet 71 is formed at the side of the extension pipe in which the blocking plate 40 is installed to fill the extension pipe and the curved pipe by introducing the hot exhaust gas discharged from the drying furnace. In addition, a curved pipe gas discharge port 61 is formed at the side of the curved pipe 60 so that the hot discharge gas introduced into the extension pipe gas inlet 71 is discharged. At this time, the curved gas discharge port 61 is connected to the gas inlet 21 of the main body tube 20 by the connecting pipe 23 to supply the hot exhaust gas of the curved tube 60 to the main body tube 20. Here, the connecting tube may be formed of a flexible tube to facilitate the connection.

When the flow path of the exhaust gas is formed in this way, the exhaust gas introduced into the extension pipe 70 prevents the temperature decrease of the sludge conveyed to the sludge conveying pipe 90, and through the curved gas discharge port 61 to the main body pipe 20 As it is moved, the sludge conveyed to the sludge transfer branch pipe 30 installed in the main body tube is exchanged with the sludge transferred to the sludge transfer branch pipe to be preheated to be discharged through the gas outlet 22 of the main body tube.

Figure 5 is a schematic diagram showing a sludge preheater according to another embodiment of the present invention, the body tube itself is bent form. In this embodiment, one side of the main body pipe 20 is bent into a curved surface, so that the sludge feed branch pipe 30 piped inside the body pipe of the bent portion is also bent so that the sludge conveyed through the sludge feed branch pipe is switched direction If it is, the preheating will continue.

Here, when one side end of the bent sludge preheater 13 is directly connected to the drying furnace, the sludge introduced into the sludge preheater is continuously heat exchanged until it is introduced into the drying furnace. Of course, between the bent sludge preheater and the drying furnace may further be provided with an extension pipe or curved pipe to further change the transfer direction.

As shown in FIG. 6, the sludge preheater 13 is composed of a main tube 20, a curved tube 60, and an extension tube 70, and a sludge feed branch pipe 30 is installed in each tube to communicate with each other. You can achieve the same / similar effect.

That is, the sludge preheater 13 has a gas outlet 22 is formed on the side to discharge the discharge gas therein, one side surface is in communication with the sludge supply pipe 80 and the main body pipe 20 is supplied with the sludge ; A curved pipe 60 in which one end is communicated with the other end of the main body pipe; An extension pipe 70 having one end portion communicating with the other end portion of the curved pipe, the other end portion being coupled to the drying furnace, and an extension tube gas inlet 71 for introducing a high temperature discharge gas into the drying furnace at a side thereof; A plurality of sludge feed branch pipes 30 installed in the main body curved pipe extension pipe to receive the sludge of the sludge supply pipe 80 and to discharge the sludge into the drying furnace; And a blocking plate 40 installed at both ends of the plurality of sludge feed branch pipes to seal a space between the sludge feed branch pipes 30 and the main body pipe 20 to prevent the discharge of high temperature exhaust gas. .

In addition, as shown in FIG. 7, a plurality of baffles 50 are installed in the body tube 20, the curved tube 60, and the extension tube 70 to move zigzag between the baffles in which the high-temperature exhaust gas is introduced. Can be. In this way, if the baffle is installed, the exhaust gas may be in uniform contact with the sludge feed branch pipes wired inside the pipe, thereby increasing heat exchange efficiency.

Low energy drying system 10 configured as described above may increase the temperature of the exhaust gas discharged from the drying furnace 14 to 100 ~ 150 ℃. In the conventional drying furnace, the operation was performed under a condition of 100 ° C. or less in order to reduce heat loss through the exhaust gas, but in the present invention, the exhaust gas of the drying furnace is reused to preheat the sludge introduced into the drying furnace to dry the sludge of the drying furnace. The amount of steam supplied can be reduced.

8 is a graph showing the steam flow rate required for the drying furnace according to the exhaust gas temperature of the drying furnace.

The base shown is a conventional drying system without a sludge preheater, and the remaining 90, 100 and 110 ° C are measured data using a drying system equipped with a sludge preheater according to the present invention. In addition, the conventional drying system and the drying system of the present invention used the sewage sludge designed to 1 ton / day per day.

As shown, the conventional drying system, the base, showed the required steam flow rate of 870 kg / h when the outlet gas outlet temperature of the drying furnace was set at 95 ° C, which is the temperature of a general drying system.

On the other hand, in the case of a drying system equipped with a sludge preheater according to the present invention, the steam flow rate used when the outlet gas outlet temperature of the drying furnace is set to 90 ° C is 780 kg / h and the outlet temperature is set to 100 ° C. When the steam flow rate was set at 760 kg / h and the outlet temperature was set at 110 ° C., the steam flow rate used was 500 kg / h.

As measured, when the outlet gas outlet temperature of the drying furnace is 110 ° C, it can be seen that the steam flow rate required for the drying furnace is reduced by about 40% or more than the steam flow rate used in the conventional drying system.

1 is a process diagram schematically showing a low energy drying system for preheating sludge using exhaust gas from a drying furnace according to the present invention.

Figure 2 is a cross-sectional view showing a sludge preheater according to an embodiment of the present invention.

3 is a cross-sectional view of the baffle mounted to the sludge preheater of FIG.

4 to 7 is a cross-sectional view schematically showing a sludge preheater according to another embodiment of the present invention.

8 is a graph showing the steam flow rate required for the drying furnace according to the exhaust gas temperature of the drying furnace.

9 is a process diagram showing a conventional drying system.

<Explanation of symbols for the main parts of the drawings>

10: drying system

11 Hopper 12 Feed Feeder

13: sludge preheater 14: drying furnace

15 condenser 16 deodorizer

17: gas-liquid separator

20: main body tube

21 gas inlet 22 gas outlet

23 connector

30: Sludge Transfer Branch

40: blocking plate

50: baffle

60: bend

61: curved gas outlet

70: extension tube

71: extension pipe gas inlet

80: sludge supply pipe

81,91: extension

90: sludge transport pipe

Claims (10)

A hopper 11 for temporarily storing high function sludge, a feed feeder 12 for supplying sludge stored in the hopper by a predetermined amount, and a high temperature feed gas supplied to the sludge supplied by the feed feeder to dry the sludge. In a drying system (10) comprising a drying furnace (14) and a deodorizer (16) for removing odors of exhaust gas discharged from the drying furnace, Mounting the sludge preheater 13 between the feed feeder 12 and the drying furnace 14, The sludge discharged from the feed feeder passes through the sludge preheater 13 to be supplied to the drying furnace 14, and the hot exhaust gas discharged from the drying furnace 14 passes through the sludge preheater 13 and then is post-treated. Low energy drying system for preheating the sludge by using the exhaust gas of the drying furnace, characterized in that configured to reduce the amount of drying heat supplied to the drying furnace by heat exchange between the sludge introduced into the drying furnace and the hot exhaust gas discharged from the drying furnace. The method of claim 1, The sludge preheater 13, A gas inlet 21 for introducing the exhaust gas to the drying furnace and a gas outlet 22 for discharging the introduced exhaust gas to the outside are formed on the side, and a sludge supply pipe 80 is connected to one end to receive the sludge. On the other end, the sludge transport pipe 90 is installed in communication with the main body pipe 20 for supplying the preheated sludge to the drying furnace; A sludge feed branch pipe 30 which is installed inside the main body pipe and is supplied with sludge of the sludge supply pipe and discharged to the sludge feed pipe; And a blocking plate 40 installed at both ends of the plurality of sludge feed branch pipes to seal a space between the sludge feed branch pipes 30 and the main body pipe 20 to prevent the discharge of high-temperature exhaust gas. Low energy drying system for preheating sludge using exhaust gas from a drying furnace. The method of claim 2, The sludge preheater 13 is a low-energy drying system for preheating the sludge using the exhaust gas of the drying furnace, characterized in that a plurality of baffles (50) installed in the main body tube to extend the movement path of the hot exhaust gas introduced into the sludge preheater (13). . The method of claim 2, The sludge preheater 13 is installed in communication with the sludge supply pipe 80, the expansion portion 81 is formed on one side of the main body pipe 20, The other end portion of the main body pipe communicating with one side end of the curved tube 60 containing the sludge conveying pipe 90, the expansion portion 91 is formed so that the conveying direction of the sludge preheated in the main body pipe is switched, The other end portion of the curved pipe communicates with one side end portion of the extension pipe 70 containing the sludge transport pipe 90 so as to be introduced into the drying furnace 14 with the sludge changed direction. The other end of the extension pipe 70 is coupled to the drying furnace by installing a blocking plate 40 between the sludge conveying pipe and the extension pipe to prevent the hot exhaust gas supplied into the extension pipe to be introduced into the drying furnace of the drying furnace Low energy drying system for preheating sludge using exhaust gas. The method of claim 4, wherein An extension pipe gas inlet 71 is formed at the side of the extension pipe 70 to fill the extension pipe and the inside of the curved pipe by introducing a high temperature discharge gas. A curved gas discharge port 61 is formed at a side surface of the curved pipe 60, and the curved gas discharge port is connected to the gas inlet 21 of the main body pipe 20 by a connecting pipe 23 so as to allow high temperature discharge gas of the curved pipe. To be supplied to the main tube, The hot exhaust gas supplied to the main body tube is preheated to the sludge conveyed through the sludge feed branch pipe 30 and then discharged through the gas outlet 22 so that the sludge is discharged using the exhaust gas of the drying furnace. Preheating low energy drying system. The method of claim 2, The main body pipe 20 is bent one side to the curved surface, and the sludge transfer branch pipe 30 inside the bent main pipe is also bent so that the conveying direction of the preheated sludge is characterized in that the discharge gas of the drying furnace Low energy drying system for preheating sludge. The method of claim 1, The sludge preheater 13, A main body pipe 20 having a gas discharge port 22 formed at a side thereof to discharge gas therein, and having one side surface connected to the sludge supply pipe 80 to receive sludge; A curved pipe 60 in which one end is communicated with the other end of the main body pipe; An extension pipe 70 having one end portion communicating with the other end portion of the curved pipe, the other end portion being coupled to the drying furnace 14, and an extension pipe gas inlet 71 for introducing a high temperature discharge gas from the drying furnace at a side thereof; A sludge feed branch pipe 30 installed in the main body pipe, a curved pipe, and an extension pipe to receive the sludge of the sludge supply pipe and discharge the sludge into the drying furnace; And a blocking plate 40 installed at both ends of the plurality of sludge feed branch pipes to seal a space between the sludge feed branch pipes 30 and the main body pipe 20 to prevent the discharge of high-temperature exhaust gas. Low energy drying system for preheating sludge using exhaust gas from a drying furnace. The method of claim 7, wherein Using a plurality of baffles (50) inside the body pipe (20), the curved pipe (60), and the extension pipe (70) to extend the moving path of the high-temperature exhaust gas introduced therethrough. Low energy drying system to preheat the sludge. The method of claim 1, The drying furnace 14 is a low-energy drying system for preheating the sludge using the exhaust gas of the drying furnace, characterized in that for driving the discharge gas is discharged at 100 ~ 150 ℃. The method of claim 1, Steam is used as the transfer gas of the drying furnace 14, and the exhaust gas discharged from the drying furnace passes through the condenser 15 to remove the moisture contained in the exhaust gas. Low energy drying system for preheating sludge.

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