KR100793828B1 - Heat treatment equipment of sludge using superheated vapor - Google Patents

Abstract

An apparatus for thermally treating sludge is provided to dry the sludge, reduce the weight of the sludge, and recycle the sludge, by jetting superheated vapor of high temperature and low pressure to the sludge while pyrolyzing and carbonizing the sludge. A vapor generation unit(10) generates superheated vapor of super high temperature and low pressure. A vapor treatment unit(20) jets the superheated vapor to sludge to pyrolyze and carbonize the sludge at a hypoxia condition. A collection unit(40) transports and collects the carbonized sludge. A hopper(30) discharges a predetermined amount of sludge. A first transport unit(32) consists of a filtering net for dropping moisture contained in the sludge, which is discharged from the hopper, to a separating tank. A second transport unit(34) transports the sludge, which is transported by the first transport unit, into the vapor treatment unit. Further, an apparatus for thermally treating sludge additionally contains a vapor main pipe, a jetting nozzle and a case.

Description

Heat Treatment Equipment of Sludge using Superheated Vapor

1 is a perspective view of a steam generator for generating superheated low pressure superheated steam.

2 is a view showing the configuration of a sludge heat treatment apparatus using superheated steam as an embodiment according to the present invention.

3 is a view showing the configuration of a sludge heat treatment apparatus using superheated steam according to another embodiment of the present invention.

♣ Explanation of symbols for main part of drawing ♣

10: steam generator 12: steam main

20: steam treatment device 23: case

24: injection nozzle 30: hopper

32, 34, 36: transfer means 33: separation tank

40: collecting device 42: collecting tank

50: chiller W1, W2: sludge

The present invention relates to a sludge heat treatment apparatus using superheated steam, and more particularly, to a sludge heat treatment apparatus using superheated steam to thermally decompose and carbonize a sludge in a low oxygen state by injecting superheated steam of ultra-high temperature and low pressure into the sludge.

In general, when the pressure is kept constant and the liquid is heated, the temperature rises, and when it reaches a certain temperature, it starts to evaporate. In this case, even if it is heated again, the temperature does not change until all evaporates and liquid and vapor coexist. This is called wet saturated steam, and what has become all steam is called dry saturated steam. When the dry saturated steam is heated again, the temperature of the steam rises, which is called superheated vapor. Using this steam can improve the efficiency of boilers, engines or turbines.

Furthermore, superheated steam is a hot, colorless, transparent gas of 100 ° C. or higher produced by heating the steam generated by boiling water without applying pressure. Heat transfer by air is limited to convective heat, but superheated steam has high thermal efficiency by heat transfer by radiant heat and condensation heat in addition to convective heat. In general, in the case of convective heat transfer, the heat transfer rate of superheated steam is about 4 to 6 times faster than the heating air, and the amount of heat retained is also 5 to 8 times more. In particular, by heat treatment in a low oxygen state, oxidation and combustion of the heated object can be suppressed. And a general boiler (Boiler) will produce a steam of 183.3 ℃ at 10kg / cm 3G pressurized pressure, and 170 ℃ of steam at 7 ~ 8kg / cm 3G.

On the other hand, in order to produce low-pressure superheated steam, there is a method of directly heating the first heated steam with a burner or indirectly heating the heat storage material using a heater and an electromagnetic induction heating method.

As a steam generator for generating such superheated steam, Patent Application No. 2004-0054539 (perfusion boiler), to which the applicant has applied for a patent, has a device for generating high-temperature superheated steam of low pressure. It has an evaporation rate of 30kg / h, a steam temperature of 541.9 ℃, and a steam pressure of 0.12kg / cm3. It is an integrated structure that is heated and reheated with one burner by installing a spiral superheater in the combustion chamber of the boiler. .

In general, sludge in sewage treatment plants is a sediment produced during sewage treatment or water purification, also called sludge. Sewage sludge contains about 50% of organic matter, and the water content is also difficult to treat because it is high from 96-98% of the first settling sludge to 99-99.5% of activated sludge.

Until now, the sludge was stabilized by anaerobic treatment, and then disposed of by dehydration and landfilling. However, this method is difficult due to the increase in the amount of sludge, so that the sewage sludge is directly mechanically dehydrated and then incinerated. In addition, methods such as wet oxidation or heat treatment have been studied.

Purified sludge is mainly composed of sucrose and aluminum hydroxide, but may contain 20 to 30% of organic matter depending on raw water. Like sewage sludge, it has a water content of 98% or more, which makes it difficult to treat and dispose of sludge, and in particular, sludge containing floc of aluminum hydroxide is difficult to dehydrate and concentrate. For this reason, more than a certain amount of purified sludge is subjected to sulfuric acid treatment to recover aluminum hydroxide with aluminum sulfate, and further improve dehydration.

The final treatment of the treated sludge is being used as a building material or a road construction material, but various studies have been conducted, but there is no method yet determined, and it is treated by landfilling. In addition, as the treatment of sludge, it is treated by ocean dumping on the high seas and composting of land or landfilling in landfills, and dumping of marine dumping is prohibited after several years according to the World Environmental Convention. Usage is decreasing.

An object of the present invention is to provide a sludge heat treatment apparatus using superheated steam for pyrolysis and carbonization of sludge, that is, treated sewage sludge treated in a sewage terminal treatment plant, etc. in a low oxygen state using superheated steam of ultra high temperature and low pressure.

In addition, the present invention thermally decomposes and carbonizes sludge in a low oxygen state by using superheated steam to generate little pollutants, and greatly reduces the volume of sludge by carbonization of superheated steam, and recycles the carbonized sludge into renewable fuel. To make it possible is another purpose.

As a means for achieving the above object, the sludge heat treatment apparatus using the superheated steam according to the present invention, in the sludge treatment apparatus,

Steam generator for generating superheated steam of ultra-high temperature low pressure state;

A steam processor for pyrolysis and carbonization in a low oxygen state by injecting superheated steam supplied from the steam generator into sludge;

It characterized in that it comprises a collection device for transporting and collecting the sludge carbonized by pyrolysis in the steam treatment device.

Hereinafter, a sludge heat treatment apparatus using superheated steam according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a steam generator for generating superheated low pressure superheated steam, and FIG. 2 is a view illustrating a sludge heat treatment apparatus using superheated steam as an embodiment according to the present invention.

First, the superheated steam used in the present invention is a steam generator 100, that is, a high-temperature superheated steam of low pressure by using a perfusion boiler having an integral structure for heating and reheating with a single burner by installing a spiral superheater in the combustion chamber of the boiler. The device that generates is applied. And the sludge to be heat treated is the sludge separated after centrifugation or precipitation in the sewage treatment plant.

Low pressure high temperature steam (about 500 ~ 1,000 ℃) generated in the steam generator 10 is connected to the steam treatment device 20 along the steam main pipe (12).

The steam treatment device 20 is a sealed shape except for a lower portion, and is formed of a case 23 in which a predetermined space is formed. Case 23 is made of a material excellent in heat insulation, it is preferable that the through-hole is formed at the position where the various sludge (W1) is introduced and discharged. The steam main pipe 22 connected to the steam generator 10 on one side of the steam processing device 20, that is, the steam main pipe 22 installed in the case 23 is branched from a plurality of steam pipes to inject superheated steam into the sludge. A plurality of injection nozzles 24 are connected. The injection nozzle 24 is to inject the high temperature superheated steam supplied from the steam main pipe 22 to the sludge W1. In addition, the case 23 is to prevent the superheated steam injected from the injection nozzle 24 to be dispersed to the outside.

And the injection nozzle 24 is to inject the high temperature superheated steam supplied from the steam main pipe 12 to the sludge (W1). The outlet of the injection nozzle 24 is a structure capable of injecting superheated steam into the sludge W1, for example, in order to reduce frictional losses of steam, it is preferable to inject the circular pipe through a predetermined orifice, but the sludge W1 Any shape may be used as long as the structure can be sprayed more easily. The injection nozzle 24 may allow the superheated steam to be injected at multiple or repetitive positions of the sludge W1 introduced into the steam treatment device 20 from the inside of the steam treatment device 20.

Furthermore, in order to be able to pyrolyze or carbonize the solid sludge (W1) containing organic matter more, superheated superheated steam is added to the sludge (W1) several times.

On the other hand, the second conveying means 34 is installed in the lower portion of the steam treatment device 20 to transport the sludge W1 at a constant speed. The first transfer means 32 is positioned at the front end or the upper end of the second transfer means 34, and the third transfer water stage 36 is positioned at the rear end or the bottom of the second transfer means 34. That is, the first conveying means 32 is for conveying and supplying the sludge W1 supplied in a predetermined amount from the hopper 30 to the second conveying means 34, and the third conveying means 36 is the second conveying means. The means 34 receives the pyrolyzed and carbonized sludge W2 and transfers the carbonized sludge W2 to the collection tank 42 for collecting the carbonized sludge W2 to be subjected to the next post-treatment process.

The first, second and third conveying means 32, 34 and 36 are means or devices capable of moving the sludges W1 and W2 at a constant speed, such as conveyor belts. In particular, the first transfer means 32 is to dehydrate and dry the water (water) contained in the sludge W1 while transferring the sludge W1 injected from the hopper 30 in a predetermined amount. The first transfer means 32 preferably has the shape of a permeation network so that the water of the sludge W1 may fall down by gravity so that the water separated from the sludge W1 may be dehydrated. Furthermore, a drying apparatus for blowing hot air may be further provided on one side of the first transfer means 32 to dry the dewatered sludge W1.

The sludge W2 carbonized by the second transfer means 34 is transferred to the third transfer means 36 and then collected in a collection tank 42 installed below the end of the third transfer means 36 and recycled as recycled fuel. Make this possible.

Furthermore, the collection tank 42 may be located immediately below the second transfer means 34 without installing the third transfer means 36 positioned below the second transfer means 34. This may be selectively added or subtracted depending on the conditions or circumstances of the workplace or the collection process.

The carbonized sludge (W2) collected in the collection tank 42 is preferably recycled or recycled as recycled fuel through a post-treatment process to be used for other purposes.

The operation of the sludge heat treatment apparatus using the superheated steam according to the present invention made as described above will be described.

First, the hopper 30 is filled with various mixed sludges W1. A certain amount of sludge W1 is supplied from the hopper 30, but the sludge W1 is transported in a state in which the sludge W1 is spread in a thin thickness on the first transfer means 32. And the metal or soil or stone contained in the sludge (W1) is preferably separated before being separated by a separate separating means or filled in the hopper 30 while passing through the first transfer means 32 composed of a permeable network. . In addition, the water contained in the sludge (W1) is preferably dropped through the transmission network while passing through the first transfer means 32 made of a transmission network to be separated into the separation tank 33.

The sludge W1 transferred through the first transfer means 32 is connected and supplied to the second transfer means 34, and the sludge W1 transferred onto the second transfer means 34 is the second transfer means ( 34 is introduced into the inlet of the case 23 of the steam treatment device 20 installed on the top. At this time, the superheated steam supplied through the steam main line 22 installed in the case 23 is injected into the sludge W1 from the plurality of injection nozzles 24 configured in the steam main line 22 in the ultra-high temperature and low pressure state. . Since the superheated steam is a high temperature steam, the carbonizable material such as wood included in the sludge W1 is carbonized (charcoal). Carbonization of the carbonizable material is carbonization by high temperature steam, not carbonization in the ignition state by supply of oxygen, and thus drying and weight of the sludge W1 are reduced without releasing harmful substances such as soot, smoke or dioxins. . In particular, for example, according to the experimental results, it was found that the pyrolysis test of the wood capable of carbonization of 600 g was reduced to about 200 g, that is, 1/3 weight. In particular, the superheated steam contains only 2% of oxygen, so wood does not undergo combustion but only carbonizes.

As such, the sludge W2 carbonized while passing through the steam treatment device 20 is transferred by the second transfer means 34 to be discharged to the outlet of the case 23 of the steam treatment device 20, and the second transfer means ( The carbonized sludge W2 which has passed through 34 is supplied to and conveyed to the third conveying means 36 of the collecting device 40.

The carbonized sludge W2 transferred to the third transfer means 36 is collected by dropping to the collection tank 42 installed at the end of the third transfer means 36. The carbonized sludge W2 collected in the collection tank 42 can be used as recycled fuel.

The third transfer means 36 may be provided with a cooling device 50 as a separate heat exchanger for cooling the carbonized sludge (W2), which is burned while the carbonized sludge (W2) is exposed to air It is to prevent that.

On the other hand, Figure 3 shows another embodiment of the sludge heat treatment apparatus using the superheated steam according to the present invention, as a steam treatment apparatus 20, using a conveying body 70 with a screw 72 is built.

The conveying body 70 is a shape of a case in which a plurality of through holes 74 are formed at a predetermined position and a lower left side, and a discharge hole 76 is formed at a right end portion, and a screw 72 that rotates inside is mounted. . The screw 72 rotates as if the sludge W1 dropped from the hopper 30 provided on the upper left side is pushed up in the right direction, and a screw drive device 80 is provided on the shaft of the screw 72. The screw drive device 80 is provided with a reducer 84 that reduces the rotational force of the motor 82 at a constant ratio, and the screw 72 shaft is connected to the reducer 84.

Further, the steam main pipe 22 is positioned above the screw 72 in the conveying body 70, and the steam main pipe 22 supplies superheated steam from the steam generator 10. In addition, a plurality of injection nozzles 24 branched from the steam main line 22 to inject superheated steam into the sludge W1 are configured, and an outlet of the injection nozzle 24 is injected into the sludge W1. In order to reduce the friction loss of steam, for example, it is preferable to spray the circular pipe through a predetermined orifice, but any shape may be used as long as it can easily inject the superheated steam into the sludge W1. . The injection nozzle 24 may inject the superheated steam at the multi-stage position of the sludge W1 introduced into the transfer body 70 from the inside of the steam treatment apparatus 20, that is, the hopper 30. Therefore, the superheated steam is added several times in order to be able to pyrolyze or carbonize a material capable of carbonization (charcoal) such as wood included in the sludge (W1). In addition, a polymer material such as a synthetic resin such as plastic may also be carbonized with superheated steam.

Separation tank 33 is located in the lower portion of the through hole 74 of the conveying body 70 so that the water contained in the sludge W1 can be separated and dropped through the through hole 74 to be separated. A collection tank 38 for collecting carbonized sludge W2 through the discharge hole 76 of the conveying body 70 is further provided.

In this configuration, as the screw 72 rotates by driving the motor 82 of the screw driving device 80 in the single conveying body 70, the sludge W1 introduced through the hopper 30 is transferred, and the sludge ( Moisture and the like contained in the W1) is separated through the through hole 74 and falls to the separation tank 33 by gravity. And when the high-temperature steam supplied through the steam main pipe 22 in the steam generator 10 is injected through the injection nozzle 24, the sludge W1 is carbonized. The sludge carbonized (W2) while passing through the injection nozzle 24 is discharged to the collection tank 38 through the discharge hole 76 formed at the end of the conveying body 70 is collected.

The degree of carbonization of the sludge W1 may be adjusted according to the position and the injection range of the injection nozzle 24 formed in the steam main line 22.

Thus, by heating the sludge discharged from the sewage terminal treatment plant using superheated steam generated in the steam generator of the present invention as superheated steam of very high temperature and low pressure, the sludge is oxidized during the process of pyrolysis and carbonization. It does not emit air pollutants such as smoke or dioxin.

While the invention has been shown and described in connection with specific embodiments thereof, it is well known in the art that various modifications and changes can be made without departing from the spirit and scope of the invention as indicated by the claims. Anyone who owns it can easily find out.

As described above, the sludge heat treatment apparatus using the superheated steam of the present invention sprays the superheated steam of ultra-high temperature and low pressure generated in the steam generator to the sludge to thermally decompose and carbonize the sludge by heat treatment to reduce drying and weight of the sludge. And recycled fuel can be realized, and furthermore, since it undergoes the process of pyrolysis without oxidizing sludge in low oxygen state, it does not emit soot, smoke or dioxin. Low pollution carbonization and recycling of sludge is possible.

Claims (5)

In the apparatus for treating sludge, Steam generator for generating superheated steam of ultra-high temperature low pressure state; A steam processor for pyrolysis and carbonization in a low oxygen state by injecting superheated steam supplied from the steam generator into sludge; A collecting device for transporting and collecting sludge carbonized by pyrolysis in the steam treatment device; Hopper to discharge a certain amount of sludge; First transport means consisting of a permeation network so that the water contained in the sludge discharged from the hopper falls into the separation tank, And Sludge heat treatment apparatus using superheated steam comprising a second transfer means for transferring the sludge transferred from the first transfer means into the steam treatment apparatus. The method of claim 1, The steam treatment device includes a steam main supplying superheated steam from a steam generator; A spray nozzle which is branched into the plurality of steam pipes and injects superheated steam into the sludge; Sludge heat treatment apparatus using the superheated steam, characterized in that the case for preventing the superheated steam injected from the injection nozzle is dispersed. delete The method of claim 1, The collection device includes a third transfer means for transferring for the collection of the pyrolysis and carbonized sludge in the second transfer means; A collection tank in which carbonized sludge transported from the third transfer means is collected; Sludge heat treatment apparatus using superheated steam further comprises a cooling device for preventing the combustion is continued while the carbonized sludge is exposed to air. The method of claim 1, The steam treatment device is a case in which a through hole and a discharge hole are formed at a predetermined position, and a conveying body having a screw rotating therein; A steam main pipe positioned at an upper portion of the screw to supply superheated steam from a steam generator; A spray nozzle which is branched into the plurality of steam pipes and injects superheated steam into the sludge; Sludge heat treatment apparatus using a superheated steam, characterized in that it comprises a screw driving device for driving the screw to rotate.

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