KR100759237B1 - Sludge drying system - Google Patents

Abstract

A sludge drying system is provided to remove malodor in exhausted gas by mixing waste heat of high temperature with exhausted gas of low temperature flowing in an exhausted gas pipe. A sludge drying system has an incinerator(10), and a dryer(30). A waste heat exhausting pipe(22) of the incinerator is connected with the dryer. A heat transferring unit(50) is installed to a secondary combustion chamber(C2) of the incinerator. The other end of an exhausted gas conduit(41), connected with an outlet of the dryer, is connected with an inlet header of the heat transferring unit. A bypass conduit(53) connects the waste heat exhausting pipe with the waste heat exhausting conduit. First and second dampers are installed to the bypass conduit and to the back of the link between the bypass conduit and the waste heat exhausting pipe. An automatic temperature controller(56) is installed to the exhausted gas conduit and opens and closes the first and second dampers respectively in the opposite direction.

Description

Sludge Drying System {SLUDGE DRYING SYSTEM}

1 is a longitudinal sectional view of an embodiment of the present invention;

2 is a cross-sectional view taken along the line A-A of FIG.

3 is a cross-sectional view taken along the line B-B of FIG.

      <Explanation of symbols for main parts of the drawings>

10: incinerator 22: waste heat discharge pipe

30: dryer 41: exhaust gas conduit

50: heat exchanger 51,52: inlet and outlet header

53: bypass conduit 54,55: first and second dampers

56: automatic temperature controller

The present invention relates to a sludge drying system, and more particularly, to a system for drying sludge having a high water content using waste heat generated in a waste incinerator.

As is well known, household wastes and industrial wastes are mainly treated by landfill and incineration methods. The above methods have advantages and disadvantages, respectively, but landfilling methods are used to secure landfills, leachate and odor, and to leave them for a long time after landfilling. Due to problems such as development delay or aesthetic defect caused by incineration, the incineration method is more and more preferred, and waste heat is generated when incineration of household waste and industrial waste (hereinafter referred to as "waste") as described above. I'm making a lot of effort.

In addition, sludge (hereinafter referred to as "sludge") generated from food waste, sewage treatment plant, wastewater treatment plant, manure treatment plant or paper mill must be transported to a third place for recycling or landfilling. In order to reduce the transportation cost because it is more than 95% by weight, the water content is usually reduced to about 80% by weight by installing a filtration (concentration) device at the place of origin, and then the water content in a drying facility installed at the place of origin or at a third place. Recycled or landfilled by reducing the weight percentage.

On the other hand, if the waste heat generated in the incinerator is used as a heat source for drying the sludge, the waste heat generated in the incinerator can be efficiently used, and since it does not use a separate energy in the drying facility, it will significantly contribute to energy saving.

A complex waste incineration and drying system for meeting the above requirements is disclosed in Utility Model Registration No. 189361. The complex waste drying system is equipped with a reburn chamber at a waste heat outlet of an incinerator and a reburn burner in the reburn chamber. To install the installation, the drying drum driven by the chain at the outlet of the reburn chamber, the stirring pin is installed on the inner wall and the impeller (blade) is installed inside, and the cyclone dust collector is installed at the outlet of the drying drum.

The complex waste incineration and drying system introduces waste heat generated by injecting waste into the combustion chamber of the incinerator into the reburn chamber. In order to maintain the high temperature, fuel is supplied to the reburn burner to reburn unburned gas in the waste heat.

In addition, the waste heat through the reburn chamber is supplied to the drying drum, and the sludge is dried by rotating the drying drum while grinding the sludge in the crusher installation hopper installed at the inlet of the drying drum.

However, the above complex waste and drying system has the advantage of efficiently utilizing the waste heat generated in the incinerator, but a serious odor occurs in the exhaust gas exhausted from the drying facility, causing secondary pollution. That is, the sludge that is added to the drying drum is often decayed (fermented), and the fermented sludge and unfermented sludge are fermented by waste heat while being agitated and dried, and thus odors cannot be avoided. In addition, even if a cyclone dust collector is installed at an outlet of the dry drum, the cyclone dust collector is only capable of separating solids and gases, thereby making it impossible to remove odor generated in the dry drum.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sludge drying system capable of correcting the above problems and satisfactorily preventing the occurrence of odor with a simple configuration.

In order to achieve the above object, the present invention comprises an incinerator and a dryer, in the system for drying the sludge by waste heat by connecting the waste heat discharge pipe of the incinerator to the dryer, the heat exchanger is installed in the secondary combustion chamber of the incinerator Connecting the other end of the exhaust gas conduit connected to the outlet of the dryer to the inlet header of the heat exchanger and connecting a bypass conduit between the waste heat exhaust pipe and the exhaust gas conduit, wherein the bypass conduit and the waste heat exhaust pipe A first damper and a second damper are respectively installed behind a connection point of the bypass conduit, and a thermostat is installed in the exhaust gas conduit so that the first and second dampers are controlled by an output signal of the thermostat. Each is configured to open and close in the opposite direction.

1 to 3, an incinerator 10 and a dryer 30 are provided, and the incinerator 10 includes a hopper having a damper 13 disposed in front of the furnace body 11. 12), the incineration product conveying cylinder 14 is installed in the lower portion of the hopper 12, and a fixed fire grate 15 and a movable grate 16 are installed. The upper part of the grate 15 and 16 is formed as the primary combustion chamber C1, and communicates with the primary combustion chamber C1 at the central portion of the furnace body 11 and induces flames vertically from the ceiling of the furnace body 11. The secondary combustion chamber C2 having the member 17 is formed, and the waste heat outlet 18 is formed at the rear of the furnace body 11, and the auxiliary burner 19 is provided at the front of the furnace body 11. The ignition burner 20 and the see-through window 21 are installed below the center.

The dryer 30 supports the drying drum 31 with the rollers 32a and 32b to rotate the chain driving means 33, and installs a stirring piece 34 on the inner wall of the drying drum 31. The rotating shaft 36 supported by the support (35a) (35b) is installed to install a plurality of stirring blades 37 on the rotating shaft 36 to drive the rotation by the chain drive means 38, and the drying drum ( 31 is supported at both ends by the support members 39a and 39b installed on the support posts 35a and 35b, and the sludge crushing and transfer hopper 40 is provided on the one side (inlet side) support member 39a. It is installed, by connecting the waste heat discharge pipe 22 connected to the waste heat outlet 18 of the incinerator 10 to the drying drum 31, and supplies the waste heat generated in the incinerator 10 to the dryer 30, Dropping the sludge stored in the sludge crushing and conveying hopper 40 into the drying drum 31 to dry the sludge by waste heat to be.

The incinerator 10 and the dryer 30 are similar to the technical means described in the prior art, and the incinerator 10 and the dryer 30 itself are not technical features of the present invention. 10) and the dryer 30 can be used other well-known in addition to the above is a matter of course.

In addition, the present invention provides a tubular heat exchanger (50) in the secondary combustion chamber (C2) of the incinerator (10) and exposes the inlet header (51) and the outlet header (52) to the outside of the furnace body (11). And the other end of the exhaust gas conduit 41 connected to the other side (outlet side) support member 39b of the dryer 30 to the inlet header 51 of the tubular heat exchanger 50. A bypass conduit 53 is connected between the waste heat exhaust pipe 22 and the exhaust gas conduit 41, and is connected to the bypass conduit 53 between the bypass conduit 53 and the waste heat exhaust pipe 22. First and second dampers (54) and (55), respectively, and a thermostat (56) are installed in the exhaust gas conduit (41), and the output signal of the thermostat (56) The first and second dampers 54 and 55 are opened and closed in opposite directions, respectively.

The heat exchanger (50) is provided with an inlet straight pipe (150a) and an outlet straight pipe (150b) made of a corrosion-resistant and heat-resistant alloy, such as Inconell, to penetrate the furnace body 11 transversely. The cover 153 is positioned at the inlet header 51 and the outlet header 52, and the cover 153 is formed at the other end to integrate the inlet and outlet straight pipes 150a and 150b. By hinge coupling 154, the cleaning of the heat exchanger 50 is quick and easy.

The outlet header 52 is connected to a gas discharge pipe 57 to be discharged to the atmosphere after passing through a temperature reduction facility (not shown). The temperature reduction facility is a waste heat hot water boiler or a cooling tower. In addition, a cyclone dust collector 42 is installed in the exhaust gas conduit 41 to separate solids, and a temperature sensor 23 is installed in the waste heat discharge pipe 22 to operate the auxiliary burner 19 by the output signal. This is to achieve complete combustion of the incinerated object.

In the present invention as described above, the capacity of the incinerator 10 is generally about twice the capacity of the dryer 30, and a connection point of the bypass conduit 53 between the bypass conduit 53 and the waste heat discharge pipe 22 is provided. The rear cross-sectional area is formed to be about 55:45, the temperature automatic controller 56 installed in the exhaust gas conduit 41 is set to operate around 250 ℃.

Therefore, when the incineration material is dropped into the primary combustion chamber C1 of the incinerator 10 and burned, the combustion heat generated during combustion is supplied to the drying drum 31 via the waste heat discharge pipe 22 and the sludge crushing and transporting hopper ( When the sludge stored in 40 is rotated into the drying drum 31 while the drying drum 31 and the rotating shaft 36 are rotated, the sludge is dried by the waste heat and discharged to the outlet formed in the support member 39b. In the initial operation of 30, the combustion temperature of the incinerator 10 is low and the dryer 30 is cooled, so that the temperature of the exhaust gas exhausted from the exhaust gas conduit 41 is lower than the set temperature of the temperature automatic controller 56. Since the second damper 55 is fully opened and the first damper 54 is fully closed, the waste heat discharged to the waste heat discharge pipe 22 is supplied to the dryer 30 and the bypass conduit 53. Is not supplied.

The exhaust gas exhausted to the exhaust gas conduit 41 performs a drying function of the sludge, and the temperature is lowered, and the bypass conduit 53 is also closed, so that the temperature below the set temperature of the temperature automatic controller 56 is maintained. After being introduced into the furnace heat exchanger 50, the furnace is heated to only a low temperature by high temperature waste heat in the secondary combustion chamber C2, and then discharged in a state in which odor is partially contained in the gas discharge pipe 57.

When the initial operation is completed and the normal operation (ideal operation) is reached, the temperature of the exhaust gas exhausted to the exhaust gas conduit 41 becomes higher than the set temperature, and the second damper 55 is proportional to the set temperature increased. Closed and the first damper 54 is opened, the waste heat of the high temperature (about 900 ℃) discharged from the waste heat discharge pipe 22 to the bypass conduit 53 is supplied to the exhaust gas conduit 41 to the exhaust gas conduit 41 By mixing with the low temperature exhaust gas flowing through the high-temperature (700 ℃) exhaust gas flows into the heat exchanger 50, the high-temperature exhaust gas is a high temperature heat of combustion (900 ℃ ~ 1050 ℃) in the secondary combustion chamber (C2) The odor contained in the exhaust gas is decomposed and eliminated while being heated by), and when the unburned gas (Co) is included in the waste heat discharged from the secondary combustion chamber (C2), it is completely burned.

In addition, by controlling the amount of heat supplied to the drying drum 31 by controlling the opening and closing of the first and second dampers 54, 55 installed in the bypass conduit 53 and the waste heat discharge pipe 22 to the type of sludge to be dried. It is possible to perform good drying regardless of particularity.

As described above, the present invention provides a heat exchanger in an incinerator, and connects a bypass conduit to a waste heat discharge pipe for supplying waste heat to the dryer in the incinerator and an exhaust gas conduit connected to the outlet of the dryer, and bypasses the bypass conduit and the waste heat discharge pipe. The first and second dampers are installed behind the connection point of the pass conduit, respectively, and the high temperature waste heat is supplied to and mixed with the low temperature exhaust gas flowing through the exhaust gas conduit according to the set temperature of the thermostat installed in the exhaust gas conduit. By heating in the air, odor generation can be satisfactorily prevented by the simple structure and the unburned gas can be completely burned without increasing the installation area.

Claims (4)

An incinerator and a dryer, wherein the incinerator forms a secondary combustion chamber in communication with the primary combustion chamber and the primary combustion chamber, and connects a waste heat discharge pipe formed in the secondary combustion chamber to a dryer to dry the sludge by waste heat. And a heat exchanger in the secondary combustion chamber, and connecting the other end of the exhaust gas conduit connected to the outlet of the dryer to the inlet header of the heat exchanger, and between the waste heat exhaust pipe and the exhaust gas conduit. Connecting a pass conduit, and installing first and second dampers, respectively, behind a connecting point of the bypass conduit of the bypass conduit and the waste heat exhaust pipe, and installing a thermostat on the exhaust gas conduit, And a sludge drying system configured to open and close the first and second dampers in opposite directions, respectively, by an output signal from a regulator. The cover of claim 1, wherein the heat exchanger includes an inlet straight pipe and an outlet straight pipe penetrated through the furnace body so that one end thereof is positioned at the inlet header and the outlet header, respectively, and the other end integrates the inlet and outlet straight pipe. Sludge drying system installed. The sludge drying system according to claim 2, wherein the door is hinged to the cover. The sludge drying system of claim 2, wherein the inlet and outlet straight pipes are Inconel.

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