JPH08121735A - Sludge drying, incinerating and melting treatment system and combustion and melting treatment method thereof and differential pressure control system - Google Patents

Abstract

PURPOSE: To dry and burn moisture in sludge safely without providing any public pollution, smoothen the smelting of molten ash, facilitate the outflow of the same, permit the regulation of solidifying and granuating after outflow, and contrive reutilization. CONSTITUTION: A dryer 1, drying by inert gas, a sludge burning and melting furnace 11, burning organic substances in sludge and melting inorganic substances, are provided while a smelt take-out port 78 is provided on the bottom of the furnace 11. A sludge drying, burning and melting treatment system is provided with a paper extracting line, provided in a sludge recovering seal tank, a secondary combustion furnace 20, burning unburnt organic substances completely, a drain injection nozzle 23, faced toward the inside of the furnace, the main body 25 of convection heat transfer unit, the storage tank 61 of inert gas for drying, a drying medium gas heater 28, provided on the half way of an inert gas supplying passage from the storage tank 61 to the dryer 11 and arranged in the main body 25 of convection heat transfer unit, and an exhaust gas scrubber 38, removing public pollutant contained in the exhaust gas of combustion, which is discharged through the main body 25 of convection heat transfer unit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pollution-free treatment technique for sewage sludge such as various industrial waste sludge containing a large amount of water, river sludge, domestic wastewater, and human waste, and in particular, heating and drying of sludge. Sludge dry combustion melting treatment system that completely burns the malodorous component that vaporizes with steam during treatment to make it pollution-free, and further burns organic substances contained in sludge to burn and melt inorganic substances to separate and extract as smelt. The present invention also relates to a combustion melting treatment method and a differential pressure control system thereof.

[0002]

2. Description of the Related Art There are various types of dry combustion melting treatment apparatus for dehydrated cake of sewage sludge. FIG. 7 shows a practical example as a typical example. The organic sludge containing a large amount of water is supplied in the form of a cake together with a small amount of inorganic components from the sludge mixer inlet 101 into the airflow dryer 102. In the airflow dryer 102, high temperature hot gas (EX. About 450 to 350 ° C.) containing a large amount of excess air generated by the hot air generating furnace 103 that uses fuel is used to perform airflow drying, and the dehydrated cake (water content about 70 to 80% content) to evaporate the water content, and sludge separation cyclone 104 at the outlet
Is collected as dehydrated and dried sludge powder (water content of 10% or less), and part of it is returned to the sludge mixer inlet 101 via the distributor 105, mixed with the cake and put into the airflow dryer 102 for recirculation. The sludge treatment amount is conveyed as a dry powder cake by the cool air introduced by the blower 106 through the sludge transport pipe 107, and the sludge burner 108 melts the sludge in the melting furnace 109.
It is thrown in. The furnace 109 is provided with an auxiliary combustion burner 110 and a combustion air nozzle 111, burns dry sludge and melts inorganic substances, introduces exhaust gas into the secondary combustion furnace 112 from the furnace outlet, and melts inorganic substances into the sludge combustion melting furnace 1
It is extracted as molten smelt from the bottom of 09 and taken out as cooling slag from the seal tank 125. The medium for drying the cake is generated in the hot air generating furnace 103, and the exhaust gas containing a large amount of excess air used for drying the cake is blower 1
After separating the water through 13 and the scrubber 114, it is discharged from the dry exhaust gas nozzle 115 into the secondary combustion furnace 112. On the other hand, the drying medium heater 118 is branched as a circulation gas for drying and is installed on the downstream side of the combustion air heater 116.
Then, the temperature is raised (250 ° C.) to reach a high temperature through the hot air generating furnace 103, and the gas is circulated through the airflow dryer 102. A combustion air heater 116 is provided at the outlet of the secondary furnace, and the air is introduced by a blower 117 to reach a high temperature and is injected from a combustion air nozzle 111 installed in the sludge combustion melting furnace 109. Drying medium heater 118 rather than combustion air heater 116
The gas discharged through the exhaust gas is introduced into the exhaust gas heat exchanger 120 through the secondary furnace exhaust gas duct 119, mixed with the heated air having a high temperature through the scrubber 121, and discharged from the chimney 124.

[0003]

DISCLOSURE OF THE INVENTION In the combustion and melting treatment method of sludge composed of a mixed component of organic matter and inorganic matter containing a large amount of water, the system is simplified, the efficiency is improved, the product is made pollution-free, and the ash content is reduced. It is a necessary condition that the smelt discharged as is smoothly melted. Generally, hydrous sludge has a water content of 95% or more, and is primarily dehydrated by a belt press (not shown) or the like and supplied as a dehydrated cake. However, even such a cake-like sludge has a large amount of water (about 70 to 80%), and combustion treatment is not possible with that slag. Therefore, it is necessary to remove moisture using a drying device. It is necessary to raise the temperature of the circulating gas in the airflow drying device which is widely used at present in order to improve efficiency. In the reference, since only the drying medium heater 118 is insufficient, the hot air generating furnace 103 is provided to perform the generation and supply of the circulating gas and the heating by the fuel burner. (EX
The gas heater outlet is about 250 ° C and the hot blast stove outlet is about 420 ° C) Further, a cold air blower is provided for this burner combustion, and a large amount of excess air is contained in the circulating gas. Therefore, the following problems arise. (1) Limitation on drying conditions In the airflow dryer 102 used in such a state, the water content in the dried sludge is limited, and fire prevention is required.
Airflow dryer 102 inlet temperature ≤ 450 degrees C, outlet water ≥ 1
It is generally suppressed to about 0%. Therefore, there is a limitation in the operation of the drying device, which is a disadvantage in improving efficiency. (2) Limitation on transportation of dry sludge Further, since the dry sludge is transported by air by a blower, there is a risk of burning damage, explosion, etc. due to backfire of the 109 flame in the furnace in the transport pipe, and to prevent these. It is necessary to use cold air to lower the temperature in the tube and to set the transport flow velocity to be equal to or higher than the propagation velocity of the flame of the dry sludge. Therefore, the range of low-load operation is limited, which is disadvantageous in operating the device. (3) Problems of Combustion-Melting Furnace In the sludge combustion-melting furnace 109, the moisture content of the dried sludge conveyed is suppressed to a high level and the temperature is low, so ignition delay and combustion time become long. Therefore, it is necessary to increase the size of the sludge combustion / melting furnace 109 to require a sufficient mixing and combustion time, increase the amount of auxiliary fuel, and the like, and the internal pressure by the steam vapor generated from the water seal water in the slag tank 125 causes smelting. Since it is difficult to perform a smooth discharge process, it takes time to remove. Therefore, the facility cost and the operating cost are disadvantageous because of the increase of the facility cost, the auxiliary combustion amount, and the operation and maintenance cost. (4) Problems in system configuration On the other hand, in the secondary combustion furnace 112, the combustion air heater 116 and the drying medium heater 1 are provided at the exhaust gas outlet for recovering exhaust heat.
Since 18 is provided in the series, there is a limit to the rise of the circulating gas outlet temperature in the drying medium heater 118 on the downstream side. (EX 250 ° C.) Therefore, it is necessary to further raise the temperature by using the auxiliary fuel burner by the hot air generator 103 for drying. (EX 420 degree C) Therefore, "The system configuration becomes complicated, and the energy consumption increases with the extra equipment for operation, which causes an economic disadvantage." (5) Problems in pollution control The temperature inside the sludge melting furnace is usually ≥ 1,300-1,500
It has a degree C, thus the generation amount of the NO _X often because reduction measures are required.

The present invention was made in view of the above problems and was devised to solve the problems. The object of the present invention is to provide a sludge composed of a mixed component of an organic substance and an inorganic substance containing a large amount of water. Drying and burning sludge to minimize the amount of ash discharged and then melting and smelting and discharging, and in this case, the moisture in the sludge is dried and burned safely and pollution-free, and the smelted ash is melted. Sludge dry combustion / melting treatment system and its combustion / melting treatment method and differential pressure control system capable of smoothly performing discharge, facilitating outflow, and adjusting solidification and granulation after outflow to measure reuse Is provided.

[0005]

In order to achieve the above object, the invention of claim 1 is a gas stream drying for drying a sludge composed of a mixed component of an organic substance and an inorganic substance containing a large amount of water by a high temperature inert gas. The furnace is equipped with a sludge combustion melting furnace that burns the organic matter in the sludge dried by the airflow dryer and melts the inorganic matter in the sludge by the high temperature combustion gas generated in the furnace, and melts the inorganic matter from the bottom of the furnace as smelt. A smelt outlet for separation and extraction is provided at the bottom of the sludge combustion melting furnace, and a secondary combustion furnace that completely burns the unburned organic matter contained in the high-temperature exhaust gas after the separation and removal of molten inorganic matter is installed, and is dried in an airflow dryer. Occasionally, NO is generated in the furnace as the malodorous component contained in the drain part of the dry-removed water vaporized from the sludge is oxidized and removed by the excess oxygen.
_In order to reduce _X, a drain injection nozzle for injecting a portion of the dry-removed water into the secondary combustion furnace is installed facing the secondary combustion furnace, and the combustion exhaust gas of the sludge combustion melting furnace and the secondary combustion furnace is installed. A convection heat transfer body for convection, a drying inert gas storage tank for supplying an inert gas to the airflow dryer, and a passage for supplying an inert gas from the drying inert gas storage tank to the airflow dryer. A drying medium gas heater provided on the way is arranged in the convection heat transfer section body, and an inert gas passing through the drying medium gas heater by using convection combustion exhaust gas in the convection heat transfer section body. Of the sludge combustion and melting furnace and the secondary combustion furnace through the convection heat transfer section body to remove the pollutant components contained in the combustion exhaust gas. Here, in a preferred embodiment, the sludge combustion melting furnace main body is made rigid or horizontally placed, and can be conically swung within a predetermined tilt angle range with the furnace outlet as a reference point to accelerate the melting of the inorganic matter in the sludge solid matter. It is advisable to install the sludge combustion and melting furnace main body in. In addition, upstream of the drying medium gas heater provided in the middle of the passage for supplying the inert gas from the drying inert gas storage tank to the air flow dryer for the inert gas that has become low temperature due to sludge drying through the airflow dryer. It is preferable to provide a circulation passage in the side passage for recirculation. In addition, upstream of the drying medium gas heater provided in the middle of the passage for supplying the inert gas from the drying inert gas storage tank to the air flow dryer for the inert gas that has become low temperature due to sludge drying through the airflow dryer. A circulation passage is provided in the side passage, a scrubber is provided in the middle of the circulation passage, and a passage is provided to discharge the drain generated in the scrubber to the outside.The water in the sludge is vaporized and evaporated in the airflow dryer and is scrubbed with the medium into the scrubber. It is recommended that it be introduced and drained so that it can be removed. In addition, a part of the exhaust gas discharged from the main body of the convection heat transfer section is circulated in the middle of the path for supplying the inert gas from the drying inert gas storage tank to the airflow dryer. It is advisable to provide a line that uses a part of it. In addition, a medium gas extraction pipe is provided which branches from the midway of the passage for supplying the inert gas from the drying inert gas storage tank to the airflow dryer and communicates with the secondary combustion furnace.
In order to avoid the concentration of the non-condensable components in the medium, it is preferable to provide a line for extracting a part of the gas and introducing it into the secondary combustion furnace for complete combustion. In addition, each burner, which is an ejection passage for ejecting dry sludge, fuel, combustion air, etc. into the furnace, has a plan view on the side peripheral surfaces of the sludge combustion melting furnace and the secondary combustion furnace in order to generate a swirling flow in the furnace. In the above, it is preferable that a plurality of eccentricity be provided from the center of the furnace and that the tilt angle be freely changed in the vertical and horizontal directions. In addition, a combustion air heater provided in the middle of the passage for supplying the combustion air to the sludge combustion melting furnace and the secondary combustion furnace is arranged in the main body of the convection heat transfer section to heat the combustion air to the combustion air. It is better to let the mixture pass through the vessel at a higher temperature and promote combustion. Also, the inside of the convection heat transfer section main body is partitioned by a partition wall, and the drying medium gas heater and combustion air are supplied to the sludge combustion melting furnace and the secondary combustion furnace inside the convection heat transfer section main body partitioned by the partition wall. The air heater for combustion provided in the middle of the passage is installed side by side, and a convection heat transfer section outlet distribution damper is provided at the outlet of the convection heat transfer section main body that is partitioned by the partition wall and installed in parallel. It is preferable to control the flow rate distribution of the combustion exhaust gas passing through the medium gas heater and the air heater by the convection heat transfer section outlet distribution damper. Further, an exhaust gas extraction duct for transporting dry sludge is provided which is branched from a passage for discharging exhaust gas of the convection heat transfer section main body and communicates with the sludge combustion / melting furnace in the middle of the passage for sending dry sludge. It is advisable to provide an ejector at the downstream end so that part of the exhaust gas discharged from the convection heat transfer section main body is used as a transport fluid for the dried sludge into the sludge combustion melting furnace. In addition, the removal device that removes the pollution components contained in the combustion exhaust gas consists of an exhaust gas scrubber, and a heat exchanger that measures measures against white smoke at the scrubber outlet is installed on the downstream side of the exhaust gas scrubber outlet duct. A passage that circulates a part of the exhaust gas to the secondary combustion furnace as a recirculation gas is provided in the middle of the heat exchanger outlet duct where the exhaust gas that released heat flows down, and the temperature of the secondary combustion furnace outlet is controlled by using the recirculation gas. It is better to control it.

According to the second aspect of the present invention, sludge composed of a mixture of organic and inorganic components containing a large amount of water is dried by a high temperature inert gas, and then the sludge is put into a sludge combustion melting furnace to remove the sludge. Inorganic matter in the sludge is melted by the generated high-temperature combustion gas in the furnace and separated and extracted as smelt from the bottom of the furnace, and the high-temperature exhaust gas after separation and removal of the molten inorganic matter is introduced into the secondary combustion furnace. In addition to measuring the complete combustion of unburned organic matter, a portion of the dry-removed water vaporized from the sludge when it is dried by high temperature inert gas is jetted into the secondary combustion furnace to introduce the malodorous components contained in the drain. It is a method for removing NO _x generated in the furnace while oxidizing and removing with excess oxygen.

Further, in the invention of claim 13, in a device which makes it possible to adjust solidification and granulation of smelt separated and extracted from a sludge combustion melting furnace by water cooling or air cooling, the pressure in the sludge recovery seal tank is constantly sludge burned. A part of the steam vapor (or gas) generated in the sludge recovery seal tank is extracted and discharged to the inlet duct of the exhaust gas scrubber so that the pressure inside the sludge recovery seal tank is controlled so that the pressure difference is lower than the internal pressure of the melting furnace. It consists of a differential pressure control system that maintains a negative pressure and stabilizes the smelt flow.

[0008]

The present invention having the above-described structure operates as follows. That is, the inert gas released from the drying inert gas storage tank is convectively transferred while passing through the drying medium gas heater in the convective heat transfer section main body while flowing down the passage and being sent to the airflow dryer. It is heated to a high temperature by the convection combustion exhaust gas in the main body of the heat section and is introduced into the airflow dryer. Also,
Sludge consisting of a mixture of organic and inorganic components with a reduced water content, which has been subjected to primary dehydration treatment in advance, flows into this airflow dryer, and the sludge is airflow dried by a high temperature inert gas in the airflow dryer to dry. It is discharged as sludge. The dry sludge discharged from the airflow dryer is sent to the sludge combustion melting furnace, the organic matter in the dry sludge is burned in this sludge combustion melting furnace, the inorganic matter in the dry sludge is melted and separated and extracted from the bottom of the furnace as smelt. To be done. Further, the unburned organic matter contained in the high temperature exhaust gas after the separation and removal of the molten inorganic matter is completely burned in the secondary combustion furnace. In addition, a part of the gas containing the malodorous component vaporized and evaporated from the sludge in the airflow dryer is drained on the way and sent to the secondary combustion furnace where it is burned and oxidized to remove the malodorous component and is generated in the furnace. Reduce NO _x . The combustion exhaust gas from the sludge combustion melting furnace and the secondary combustion furnace is discharged by raising the temperature of the inert gas that is convected in the convection heat transfer section body and is supplied to the airflow dryer, and the pollution components contained in the combustion exhaust gas. It is removed and released into the atmosphere.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described more concretely with reference to the embodiments shown in the drawings. Here, FIG. 1 is an overall system diagram of the sludge drying and combustion melting system according to the present invention,
2 (A) and 2 (B) are side views and a plan view showing the burner tilt angle adjustment, and FIGS. 3 (A) to 3 (F) are cross-sectional views taken along arrows in FIGS.

A sludge cake mixer 1 is provided with a sludge cake inlet 1 for introducing sludge cake that has been pretreated into a cake by a dehydrator (not shown). A sludge cake and a high temperature inert gas are mixed in the sludge cake mixer 2, and a hammer mill 3 also serving as a crushing blower is provided on the downstream side of the sludge cake mixer 2. An air flow dryer 4 is arranged downstream of the hammer mill 3, and the sludge cake and high temperature inert gas in the sludge cake mixer 2 are air flow dried provided downstream of the hammer mill 3 via the hammer mill 3. It is sent to machine 4.

The airflow dryer 4 evaporates the water contained in the sludge cake (water content: about 70 to 80%) with a high degree of dryness in a high-speed stream of high-temperature inert gas to dry the sludge powder to a water content of about 5%. Equipment. An upstream end of the airflow outlet duct 5 is connected to the outlet side of the airflow dryer 4. The other end on the downstream side of the air flow outlet duct 5 is connected to a sludge separation cyclone 6, and the high temperature inert gas containing sludge dried by the air flow dryer 4 and the water vaporized from the sludge is the air flow outlet duct 5. To the sludge separation cyclone 6.

The sludge separation cyclone 6 is a flash dryer 4
A device for separating the highly dried sludge powder discharged from the tank and the inert gas containing the vaporized water. The sludge separation cyclone 6 has a cyclone outlet paper tube through which the inert gas containing the vaporized water passes. One end on the upstream side of 51 is connected. Cyclone outlet paper tube 5
A cyclone outlet paper tube blower 52 for blowing an inert gas is provided in the middle of 1, and the other end on the downstream side of the cyclone outlet paper tube 51 is connected to a paper scrubber 53.

The paper scrubber 53 is a device for removing moisture and harmful components from the inert gas discharged through the cyclone outlet paper pipe 51, and an ejector for ejecting water like a shower is provided above the inside thereof. Therefore, the water is ejected in a shower shape to dissolve and remove the harmful components contained in the inert gas in the shower water.

To the upper end of the paper scrubber 53, one end of a paper scrubber outlet exhaust pipe 54 for discharging the inert gas from which harmful components have been removed is connected. The other end of the paper scrubber outlet exhaust pipe 54 is connected in the middle of a drying medium transport pipe 55, which will be described later, to recirculate an inert gas. That is, by connecting the paper scrubber outlet exhaust pipe 54 to the drying medium transport pipe 55,
A dry medium closed loop is formed.

One end of a drain discharge pipe for discharging the waste liquid in the paper scrubber 53 is connected to the lower end of the paper scrubber 53, and a drain pump 67 is provided in the middle of the drain discharge pipe.
Is provided. The downstream side of the drain discharge pipe is branched and connected to the paper scrubber drain discharge pipe 68 and the paper scrubber drain branch pipe 69. Of these, the paper scrubbing drain discharge pipe 68 is connected at its downstream end to a drain receiving tank 49 described later. The downstream end of the paper scrubbing drain branch pipe 69 is connected to a drain injection nozzle 23 of the secondary combustion furnace 20 described later.

A sludge distributor 7 is connected to the sludge separation cyclone 6. The sludge distributor 7 is connected with a recirculation supply pipe and a dry sludge supply pipe 9 communicating with the dry sludge mixer inlet 8 of the sludge cake mixer 2, and a part of the sludge is distributed by the sludge distributor 7. Then, it is returned to the sludge cake mixer 2 through the dry sludge recirculation supply pipe 8a.

An ejector 73 is connected to the downstream end of the dry sludge supply pipe 9, and the ejector 73 is connected to the dry sludge transport pipe 10. The downstream end of the dry sludge transport pipe 10 is connected to the sludge burner 12 of the sludge combustion / melting furnace 11, and the remaining sludge distributed by the sludge distributor 7 passes through the dry sludge supply pipe 9 and the ejector 73 to dry sludge transport pipe 10. After passing through the dry sludge transport pipe 10, it is sent to the sludge combustion melting furnace 11 through the sludge burner 12 and burned in the furnace, and the inorganic substances in the sludge are melted.

The sludge combustion / melting furnace 11 is a primary furnace for burning and melting sludge, and at the bottom thereof is a smelt pool 77 in which the inorganic substances in the sludge are melted, and at the center of the bottom is provided a smelt outlet 78. A sludge recovery seal tank 84 is provided below the sludge recovery seal tank 84, and smelt produced by melting inorganic substances in the sludge in the furnace is discharged from the smelt extraction port 78 to the outside of the sludge combustion melting furnace 11 to recover sludge. It falls into the seal tank 84 and is collected as cooling sludge.

On the outer peripheral surface of the sludge combustion / melting furnace 11, a sludge burner 12, a secondary air air box and damper 13 for the sludge burner, an auxiliary combustion burner 14, a secondary air air box and a damper 15 for the auxiliary combustion burner, and a primary furnace. Outlet secondary air nozzle 1
Each connecting pipe 8 is mounted eccentrically with respect to the center of the furnace in plan view so that a swirling flow is generated in the furnace.

A secondary combustion furnace 20 of a secondary furnace is provided above the sludge combustion and melting furnace 11 of the primary furnace. The secondary combustion furnace 20 is in communication with the sludge combustion melting furnace 11,
This communication part is narrowed down. The secondary combustion furnace 20 is a portion that completely burns the exhaust gas generated during combustion in the sludge combustion melting furnace 11. The auxiliary combustion burner 21 for the secondary combustion furnace, the secondary combustion furnace 21, and the secondary combustion furnace are provided on the outer peripheral surface of the secondary combustion furnace 20. For burner burner 2
The connecting pipes of the next air wind box and damper 22, the drain injection nozzle 23, and the medium gas inlet 76 are eccentrically attached to the center of the furnace as seen in a plane so that a swirling flow is generated in the furnace.

The auxiliary combustion fuel supply pipe 16 is a passage for supplying fuel to the sludge combustion / melting furnace 11 of the primary furnace and the secondary combustion furnace 20 of the secondary furnace, and an auxiliary combustion control valve 17a is provided in the middle thereof. The downstream side is branched and connected to the auxiliary combustion burner 14 of the sludge combustion melting furnace 11 and the secondary combustion furnace auxiliary combustion burner 21 of the secondary combustion furnace 20, respectively. Further, auxiliary combustion burner source valves 17b are provided in the middle of the branched downstream auxiliary combustion fuel supply pipes 16, respectively.

As shown in the drawings (FIGS. 2 and 3), the burner zone fluid inlets of the respective parts are injected into the furnace in the swirling direction, and the inclination angle of each is changed vertically and horizontally to obtain the optimum injection and It should be adjustable so that combustion conditions can be obtained. For example, the vertical inclination angle θ is formed to have an inclination in the range of +30 degrees to −30 degrees, and the horizontal inclination angle ψ is formed to have an inclination of +20 degrees to −20 degrees.

A convection heat transfer section body 25 is provided above the outlet side of the secondary combustion furnace 20. Convection heat transfer unit body 2
5 communicates with the secondary combustion furnace 20, and this communicating portion is narrowed. The narrowed communication portion is formed in a circular cross-section, and a connecting pipe of a plurality of recirculation gas nozzles 24 is formed on the outer peripheral surface thereof so that a swirling flow is generated in the furnace with respect to the center of the furnace when seen in a plan view. Are eccentrically attached to each.

The convection heat transfer section main body 25 convects the combustion exhaust gas and uses the heat of the convection combustion exhaust gas to heat the combustion air heater 27 and the drying medium gas heater 28. These combustion air heaters 27 and the drying medium gas heaters 28 that utilize the combustion exhaust gas are provided in parallel in the convection heat transfer section main body 25, and are also partitioned by the partition wall 26. That is, a partition wall 26 is vertically formed at the center of the convection heat transfer section main body 25, and most of the inside of the convection heat transfer section main body 25 is partitioned by the partition wall 26 into the left and right sides, and the convection wall 26 is partitioned. The combustion air heater 27 is arranged on one side (right side in the drawing) of the heat transfer section main body 25, and the drying medium gas heater 28 is arranged on the other side (left side in the drawing).

Convection heat transfer section main body 2 partitioned by a partition wall 26
Convection heat transfer section outlet distribution dampers 29 for adjusting the amount of gas are provided at the exhaust gas outlet at the upper part of 5, respectively, so that the respective flow rates can be distributed. This convection heat transfer section outlet distribution damper 29
Is not partitioned and is in a communicating state, and one end of the convection heat transfer section outlet main duct 30 is connected to the center of the upper end thereof. The other end of the convection heat transfer section outlet main duct 30 is branched into two, one side of which is connected to the convection section heat exchange inlet duct 35, and the other side of which is a dry sludge transport exhaust gas extraction duct 70. The combustion exhaust gas is connected to the convection section outlet heat exchange inlet duct 35 and the dried sludge transport exhaust gas extraction duct 70, and flows out separately.

The downstream side of the convection section outlet heat exchange inlet duct 35 is connected to a heat exchanger 36 for heating the gas discharged into the atmosphere. One end of a heat exchanger outlet duct 37 is connected to the outlet side of the heat exchanger 36.
The other end of is connected to the exhaust gas scrubber 38.

An upstream end of a recirculation blower duct 46, which serves as a passage for recirculating a part of the exhaust gas to the secondary combustion furnace 20, is connected in the middle of the heat exchanger outlet duct 37. The other end of the recirculation blower duct 46 on the downstream side is connected to the recirculation gas nozzle 24. A recirculation blower 45 and a recirculation blower damper 47 are provided in the middle of the recirculation blower duct 46.

The exhaust gas extraction duct 70 for transporting the dry sludge, which branches from the other end side of the main duct 30 for the outlet of the convective heat transfer section, transports the dry sludge by using a part of the combustion exhaust gas, and the sludge burning and melting furnace from the sludge burner 12. An ejector 73 is connected to the downstream end of the passage for introducing the liquid into the ejector 11, and the ejector 73 communicates with the dry sludge transport pipe 10. The combustion exhaust gas flows into the dry sludge transport pipe 10 through the convection heat transfer section outlet main duct 30, the dry sludge transport exhaust gas extraction duct 70, the dry sludge transport exhaust gas blower 72, and the ejector 73, and flows down the dry sludge transport pipe 10. Then, it flows into the sludge combustion melting furnace 11 of the primary furnace through the sludge burner 12.

Exhaust gas extraction duct 70 for transporting dry sludge
A mist heater 56 is provided in the middle of the process, and the heat of the combustion exhaust gas flowing down in the exhaust gas extraction duct 70 for transporting the dried sludge is used to warm the mist heater 56. Further, an exhaust gas extraction damper 71 for transporting dry sludge and an exhaust gas blower 72 for transporting dry sludge are provided in the exhaust gas extraction duct 70 for transporting dry sludge on the downstream side of the mist heater 56.

The air inlet duct 33 is a passage for taking in the air required for combustion in the sludge combustion melting furnace 11 and the secondary combustion furnace 20, and an air inlet damper 31 and a high pressure blower 32 are provided in the middle of the air inlet duct 33. There is. The downstream end of the air inlet duct 33 is connected to the upstream end of the combustion air heater 27 disposed inside the convection heat transfer section body 25, and the air taken in from the atmosphere burns. It is heated by the commercial air heater 27 and supplied to the sludge combustion melting furnace 11 and the secondary combustion furnace 20. An upstream end of the hot air outlet duct 34 is connected to a downstream end of the combustion air heater 27.

The downstream side of the hot air outlet duct 34 is branched into a secondary air wind box and damper 13 for the sludge burner of the sludge combustion melting furnace 11, a secondary air wind box and damper 15 for the auxiliary combustion burner, and the primary furnace outlet 2. The secondary air nozzle 18 and the secondary combustion furnace secondary combustion air burner secondary air box and damper 22 of the secondary combustion furnace 20 are respectively connected. A primary furnace outlet secondary air nozzle damper 19 is provided in the middle of a hot air outlet duct 34 that is branched and connected to the primary furnace outlet secondary air nozzle 18 of the sludge combustion melting furnace 11.

The inert gas storage tank 61 for drying is the airflow dryer 4
The tank for storing the inert gas for drying used for drying is, and one end of the inert gas supply tube 63 for drying is connected to the inert gas storage tank 61 for drying. An inert gas control valve 62 is provided in the middle of the drying inert gas supply pipe 63. The other end of the drying inert gas supply pipe 63 is connected to the drying medium transport pipe 55. Drying medium transport pipe 55
The downstream end of the is connected to a mist heater 56 that warms the gas flowing down in the pipe.

An upstream end of a gas heater inlet pipe 59 is connected to the mist heater 56. A medium control damper 57 and a medium circulation blower 58 are provided in the middle of the gas heater inlet pipe 59. The downstream end of the gas heater inlet pipe 59 is connected to the upstream end of the drying medium gas heater 28 disposed inside the convection heat transfer body 25. An upstream end of a gas heater outlet pipe 60 is connected to a downstream end of the drying medium gas heater 28. The downstream end of the gas heater outlet pipe 60 is connected to the sludge cake mixer 2.

The dry inert gas supplied from the dry inert gas storage tank 61 flows down through the dry inert gas supply pipe 63 and the dry medium transport pipe 55, and is warmed while passing through the mist heater 56. The drying medium gas heater 28 is heated while flowing through the gas heater inlet pipe 59, flows into the sludge cake mixer 2 through the gas heater outlet pipe 60, passes through the sludge cake mixer 2, and the downstream side thereof. Airflow dryer 4
It flows into the inside and dries the sludge in the dryer 4.

The exhaust gas scrubber 38 is a device for removing pollution components from the exhaust gas discharged through the heat exchanger outlet duct 37, and an ejector for ejecting water in a shower shape is provided above the inside of the exhaust gas scrubber 38. Spout water like a shower,
The structure is such that the pollution components contained in the exhaust gas are dissolved and removed in shower-like water. To the upper end of the exhaust gas scrubber 38, one end of an exhaust gas scrubber outlet duct 39 for discharging the exhaust gas from which pollution components have been removed is connected.

The other end of the exhaust gas scrubber outlet duct 39 is branched into two, one side of which is connected to the scrubber outlet heat exchange inlet duct 40 and the other side of which is the exhaust gas branch duct 6.
4 is connected. Scrubber outlet heat exchange inlet duct 40
The downstream side of the exhaust gas is connected to a heat exchanger 36 that heats the exhaust gas, one end of an exhaust gas duct 43 is connected to the outlet side of the heat exchanger 36, and the other end of the exhaust gas duct 43 is connected to a chimney 44. Further, a heat exchanger outlet exhaust gas duct damper 41 and a suction blower 42 are provided in the middle of the exhaust gas duct 43, respectively.

The exhaust gas from which the pollutant components have been removed by the exhaust gas scrubber 38 passes through the exhaust gas scrubber outlet duct 39, and then the scrubber outlet heat exchange inlet duct 40 and the exhaust gas branch duct 64.
The flue gas on the one side that has been diverted into 1 is flown down through the scrubber outlet heat exchange inlet duct 40 and warmed by the heat exchanger 36, and then flows down through the flue gas duct 43 and is discharged into the atmosphere through the chimney 44.

One end of an exhaust gas branch duct 64 is connected in the middle of the exhaust gas scrubber outlet duct 39 for backing up the drying medium in the system. Exhaust gas branch duct 6
The other end of the backup exhaust gas inlet pipe 66 is connected to one end of the backup exhaust gas inlet pipe 66, and the other end of the backup exhaust gas inlet pipe 66 is connected to the middle of the drying medium transport pipe 55. An exhaust gas branching damper 65 is provided in the middle of the backup exhaust gas inlet pipe 66. Combustion exhaust gas is used to make up the inert gas during normal operation and to supplement the extracted gas,
The exhaust gas branch duct 64, the damper 65 and the backup exhaust gas inlet pipe 66 constitute a path for backing up the in-system dry medium.

An upstream end of the exhaust gas scrubber drain pipe 48 is connected to a lower end of the exhaust gas scrubber 38, and a downstream end of the exhaust gas scrubber drain pipe 48 is connected to a drain receiving tank 49. The drain receiving tank 49 is a tank for temporarily storing the waste liquid containing the pollutant components discharged from the exhaust gas scrubber 38 and the paper scrubber 53. The downstream end of the paper scrubber drain discharge pipe 68 is connected to the tank 49. ing. Also, the drain receiving tank 4
One end of a drain discharge pipe 50 for discharging the waste liquid temporarily stored is connected to the drain pipe 9.
Is configured to discharge waste liquid to the outside.

The operation based on the configuration of the above embodiment will be described below. In this figure, organic sludge containing a large amount of water is supplied in the form of a cake together with a small amount of inorganic components from the sludge cake inlet 1 to the airflow dryer 4 from the sled cake mixer 2 and the disintegrator 3 which also functions as crushing air. To be done.

In the airflow dryer 4, the water in the dehydrated cake (water content of about 70 to 80%) is evaporated by drying in the high-speed airflow of the high temperature inert recirculation gas sent by the same as above. The sludge dried in the airflow dryer 4 passes through the airflow outlet duct 5 and is collected by the sludge separation cyclone 6 as sludge powder of high dryness (water content of 5% or less).

Of these, a part of the sludge powder (water content of 5% or less) is returned to the sludge cake mixer 2 via the sludge distributor 7, the dry sludge recirculation supply pipe 8a and the dry sludge mixer inlet 8. Then, the mixture is mixed with the dehydrated cake and re-charged to the airflow dryer 4 and recirculated.

On the other hand, the sludge treatment amount is
As a highly dry powdery cake, it is conveyed as a high-temperature inert extraction gas from the exhaust gas extraction duct 70 for transporting the dry sludge through the dry sludge supply pipe 9 and the ejector 73, and the sludge burner 12 carries the primary air together with the secondary air for combustion. It is put into the sludge combustion melting furnace 11 as a furnace.

In the sludge combustion / melting furnace 11 of the primary furnace, the organic substances in the sludge charged and the inorganic substances are melted, and the exhaust gas is introduced into the secondary combustion furnace 20 from the furnace outlet. The inorganic substances are melted in the sludge combustion melting furnace 11 and accumulated as a smelt pool 77 at the bottom of the furnace.
8 is extracted and discharged as a molten smelt, and is pulverized, solidified and granulated by a fluid (water or high pressure air) ejected from a shutter nozzle 85 in a sludge recovery seal tank 84,
It falls into the water pool 86 and is collected by a conveyor (not shown).

In order to facilitate the outflow of smelt, the sludge combustion and melting furnace 11 and the sludge recovery seal tank 84
The pressure difference in the inside is detected, and the steam pressure vapor generated in the sludge recovery seal tank 84 is extracted by the differential pressure detection controller 87, and the exhaust gas scrubber 38 of the exhaust gas scrubber 38 is passed through the vapor damper 90 through the inlet damper 88 and the vapor blower 89. The heat is discharged to the outlet duct 37 of the heat exchanger on the inlet side, and the negative pressure in the sludge recovery seal tank 84 is maintained.

On the other hand, the medium for drying the cake for drying the cake in the airflow dryer 4 is an inert gas storage tank 61 (for example N 2
₂ or CO ₂ ) through the inert gas control valve 62 and the drying inert gas air supply pipe 63, and is supplied into the drying medium transport pipe 55 that constitutes the drying circulation system. The drying medium after charging in the system of the drying medium transport pipe 55 is
The drying medium transport pipe 55, the mist heater 56, the medium control damper 57, and the medium circulation blower 58 pass through the gas heater inlet pipe 59, the drying medium gas heater 28, and the drying medium gas heater 28. It is heated and heated to the inside, introduced into the sludge cake mixer 2 through the gas heater outlet pipe 60, and then enters into the airflow dryer 4 through the disstegrator 3.

The medium for drying the cake that has entered the airflow dryer 4 dries the dehydrated cake in the airflow dryer 4, passes through the airflow outlet duct 5 and the sludge separation cyclone 6 and then the cyclone outlet. From the paper pipe 51, the cyclone outlet paper pipe blower 52 enters the paper scrubber 53, where the water sprayed in the shower drains the steam to separate and remove it, and then the paper scrubber outlet exhaust pipe 54 constitutes a drying circulation system. It can be recirculated through the drying medium transport pipe 55.

Further, the non-condensable components in the drying circulation system are constituted by a drying medium transport pipe 6 which constitutes the drying circulation system in order to prevent concentration.
Partly taken out through the medium gas extraction pipe 74 branched from 0, and the medium gas extraction damper 75 is used to extract the medium gas inlet 7
It is charged into the secondary combustion furnace 20 of the secondary furnace via 6.

The drain separated by the paper scrubber 53 is discharged to the drain receiving tank 49 through the drain pump 67 and the paper scrubber drain discharge pipe 68, and a part of the drain is branched to reduce the NO _X. It is sprayed from the drain injection nozzle 23 to the secondary combustion furnace 20 through the pipe 69.

The auxiliary combustion fuel passes through the auxiliary combustion control valve 17a of the auxiliary combustion fuel supply pipe 16 and each auxiliary combustion burner source valve 17b, and then the auxiliary combustion burner 14 (for the primary furnace) and the auxiliary combustion burner 21 for the secondary combustion furnace (secondary combustion furnace). Sludge combustion melting furnace from primary furnace to primary furnace 1
They are injected into the secondary combustion furnaces 20 of the first and second furnaces, respectively.

The combustion air is supplied from the air inlet damper 31, the high pressure blower 32 and the air inlet duct 33 to the air heater 2.
7. Secondary air wind box nozzle and damper 13 for each sludge burner, secondary air wind box nozzle and damper 15 for auxiliary combustion burner, and secondary air wind box for auxiliary combustion burner for secondary combustion furnace through the hot air outlet duct 34 It is introduced into the sludge combustion and melting furnace 11 of the primary furnace and the secondary combustion furnace 20 of the secondary furnace by the damper 22 and the damper 22, respectively.

The combustion exhaust gas generated during combustion in the sludge combustion melting furnace 11 and the secondary combustion furnace 20 heats the combustion air heater 27 and the drying medium gas heater 28 of the convection heat transfer section main body 25 above the combustion exhaust gas. It is later discharged from the convection heat transfer section body 25. Then, the combustion exhaust gas discharged from the convection heat transfer section main body 25 passes through the convection heat transfer section outlet main duct 30, the convection section exit heat exchange inlet duct 35, and the heat exchanger 36. The exhaust gas releases heat while passing through the heat exchanger 36, and enters the exhaust gas scrubber 38 from the heat exchanger outlet duct 37.

A part of the exhaust gas discharged from the convection heat transfer section main body 25 branches from the convection heat transfer section outlet main duct 30 to the dry sludge transfer exhaust gas extraction duct 70, and is used for the mist heater 56 and the dry sludge transfer. Exhaust gas extraction damper 7
1. After entering the dry sludge transport pipe 10 through the exhaust gas blower 72 for transporting the dry sludge and the ejector 73, it is injected into the sludge combustion melting furnace 11 of the primary furnace through the sludge burner 12.

Further, a part of the exhaust gas discharged from the convective heat transfer section main body 25 branches from the heat exchanger outlet duct 37, passes through the recirculation blower 45 and the recirculation blower duct 46, and the recirculation blower damper 47. After that, the gas is introduced by the recirculation gas nozzle 24 provided at the outlet of the secondary combustion furnace 20, the outlet gas temperature of the secondary combustion furnace 20 is controlled to a predetermined value, and the inlet gas temperature of the convection heat transfer section main body 25 is made constant. maintain.

The exhaust gas discharged from the main body 25 of the convection heat transfer section has its pollutant components removed from the gas in the exhaust gas scrubber 38, passes through the exhaust gas scrubber outlet duct 39 and the scrubber outlet heat exchange inlet duct 40, and passes through the heat exchanger. After entering the inside of 36 and heating and raising the temperature there, it flows down through the heat exchanger outlet exhaust gas duct damper 41, the suction blower 42, and the exhaust gas duct 43, and is discharged from the chimney 44 into the atmosphere.

A part of the exhaust gas discharged from the exhaust gas scrubber 38 passes through an exhaust gas branch duct 64 branched from the middle of the exhaust gas scrubber outlet duct 39, an exhaust gas branching damper 65, and a backup exhaust gas inlet pipe 66 to form a drying circulation system. It enters into the medium transport pipe 55.

The exhaust gas scrubber 38 removes the pollutant components from the exhaust gas and the drain containing the pollutant components is temporarily stored in the drain receiving tank 49 through the exhaust gas scrubber drain pipe 48, and then discharged from the drain receiving tank 49. A drain processing device (not shown) is reached via 50.

[Other Examples] An example of application in the case where the melting temperature of the inorganic substance in the sludge is relatively high and smelt fluidization is difficult in this system is shown. Hereinafter, only another difference from the previous embodiment will be described in detail as another embodiment in relation to the present invention, the same components are designated by the same reference numerals, and only the changed portions are newly added by the reference numerals. It is a thing. The difference from the previous embodiment is the structure of the sludge combustion melting furnace 11 and the arrangement of the combustion air heater 27 and the drying medium gas heater 28 in the convection heat transfer section body 25. For the parts shown in this drawing and not specifically marked, please refer to the description of the signs in the previous embodiment. Here, FIG. 4 is an overall system diagram of a sludge drying and combustion melting system, FIG. 5 is a sludge combustion melting furnace swirling swing diagram, and FIG.
(A)-(H) is sectional drawing of each part arrow of FIG.

The sludge combustion / melting furnace 11 adopts a horizontal installation method with a slight inclination in the horizontal direction, and can be extended in the depth direction to enable combustion of sludge and a long melting and residence time of inorganic substances. The dry sludge is injected into the sludge combustion and melting furnace 11 from the sludge burner 12 through the dry sludge transport pipe 10, and burned by the high temperature air introduced from the secondary air wind box for the sludge burner and the damper 13.

The auxiliary combustion fuel is supplied from the auxiliary combustion control valve 17a through the auxiliary combustion fuel supply pipe 16 and each auxiliary combustion burner source valve 17b into the sludge combustion melting furnace 11 and the secondary combustion furnace 20, the auxiliary combustion burner 14 and the secondary combustion furnace. Secondary combustion air burner 21 and smelt melting supplementary combustion burner 79, respectively, and secondary air air boxes and dampers 15 for auxiliary combustion burners, secondary air air boxes and dampers 22 for secondary combustion furnace auxiliary combustion burners, and smelt fusion auxiliary combustion burners. It is made to burn by the high temperature air thrown in by the secondary air wind box and the damper 80. The smelt melting auxiliary burner 79 is arranged at the upper part of the smelt pool 77 and the smelt outlet 78 of the sludge combustion melting furnace 11 together with the secondary air wind box and the damper 80 for the smelt melting auxiliary burner so that the smelt smoothly melts and flows out. It measures.

The primary furnace outlet secondary air nozzle 18 and the primary furnace outlet secondary air nozzle damper 19 eject downward from above the outlet of the sludge combustion melting furnace 11 to promote combustion of residual unburned matter and prevent carryover. measure.

These burners and various nozzles have the arrangements shown in the sectional views of FIG.
It is possible to adjust the burner tilt angle as shown in (1) to the front and back and to the left and right.

The arrangement of the burners in the secondary combustion furnace 20 is the same as that of the above-mentioned embodiment, but the arrangement of the combustion air heater 27 and the drying medium gas heater 28 in the convection heat transfer section main body 25 is different for each heat absorption. In this case, the combustion air heater 27 is divided into two parts, a high temperature part and a low temperature part, which are laterally installed in the convection heat transfer part main body 25, and in the middle thereof. Although the dry medium gas heater 28 is arranged side by side in this arrangement, the dry medium gas heater 28 can be freely selected regardless of this.

As shown in FIG. 5, the main body of the sludge combustion melting furnace 11 has a conical shape with a rotation angle θ within a predetermined inclination angle φ with the furnace exit point G as a reference point.
It is intended to accelerate the melting of the inorganic matter in the swirling cladded sludge solid matter and the smooth outflow of the smelt, and to accelerate the solidification of the falling smelt by the shutter nozzle 85 cooling (water cooling or air cooling) and the control of the granularity. The present method can be effectively applied not only to the illustrated example and FIG. 4 but also to the case of the rigid melting furnace of FIG.

To carry out the above method, the sludge combustion melting furnace 1
An expansion joint 81 for a communication duct is attached to the communication duct between the main body outlet and the upper secondary combustion furnace 20 so that it can move freely, and each burner and the secondary air duct have an expansion joint 82 for the burner. , And has an expansion joint 83 for secondary air, which allows free swiveling.

According to the above embodiment, the following excellent features are provided. In a gas heater that uses a high temperature inert gas as a medium for use in a drying device and can heat a gas supplied from an inert gas (for example, N2orCO2) generator and a backup exhaust gas to a high temperature as shown in the embodiment. The temperature of the sludge is increased by 5 times, and the dehydrated cake is used as a dryer medium together with the dehydrated cake through a disintegrator and put in a dryer to dry the sludge under high temperature conditions. It is possible to keep it below%. Moreover, since a high temperature inert gas is used, no special hot gas generating burner and blower are required.

Exhaust gas that has undergone heat exchange at the outlet of the secondary combustion furnace is used as a dry sludge transport medium. As in the example, the secondary furnace exhaust gas has a moderately high temperature and the inert gas occupies most of it, and it is suitable as an air flow carrier to the burner of the separated dry powder sludge, and transports the sludge of high temperature and low water content. Also, there is no fear of backfire, and there is no fire in the transportation pipe, which is effective for safety.

As in the item [0066], high temperature, low moisture dry sludge is injected at high speed together with the high temperature secondary air at the burner port, so that combustion can be completed in a short time without ignition delay and thus the amount of auxiliary combustion. It is also advantageous in terms of equipment cost and operation.

When both the gas heater and the air heater are arranged in parallel at the outlet of the secondary furnace, both the air for combustion in the dry medium zone can be heated to a high temperature range, and the amount of gas distributed on the heat transfer surface is planned. You can select according to the conditions. The amount of gas passing through each heat transfer section can be controlled by the distribution damper according to the amount of heat absorption. Even when they are arranged in series, the respective heat transfer surface arrangements can be combined and distributed according to the required heat quantity.

Moisture in the dry sludge is removed by a scrubber, but a part of the drain is sprayed into the high temperature gas of the secondary furnace to effectively use it in preventing NO _x generation in the exhaust gas. Ingredients can be detoxified by additional high temperature oxidation. Further, a part of the non-condensable gas is extracted and put into the furnace so that it is completely combusted.

Sludge, auxiliary fuel, and secondary air are charged into the melting furnace by high-speed swirling, and the high-temperature secondary air is sludge, which is capable of performing high-load combustion by changing the inclination angle vertically and horizontally. Dampers can be adjusted from the charging port, the auxiliary fuel burner port, and the melting furnace outlet, respectively, and the inside of the melting furnace can be made to have low excess air and reduced combustion to control the temperature of the smelt to facilitate outflow. Further, the furnace main body can be swirled in a conical shape with the furnace outlet as a base point to enable smooth flow and discharge of the smelt and control of solidification and granulation after the discharge.

The secondary furnace at the exit of the melting furnace is provided with a dry medium gas extraction charging port, and swirl charging of secondary air together with an auxiliary burner for burning unburned sludge and CO gas.
Next, a part of the steam drain after drying the sludge is used as water injection for NO _X reduction, and a recirculation gas is introduced into the outlet of the secondary furnace to control the gas temperature at the outlet of the secondary furnace to a specified value. All of these inlets are capable of tilting vertically and horizontally so that stirring and mixing are good.

[0073]

As described above, according to the first and second aspects of the present invention, a closed system airflow drying apparatus using a high temperature inert gas, a sludge combustion melting furnace as a primary furnace for performing combustion melting, and secondary combustion furnace as a secondary furnace to measure the combustion and low NO _X reduction of residual unburned, and configured by a convective heat transfer body with a built-in convective heat transfer section to the safety and economic equipment systems, pollution-free The effective operation is measured by and has the following effects.

Since a high temperature inert gas that can be circulated as a drying medium is used in the drying system for sludge cakes containing a large amount of water, there is no risk of internal ignition and burning, and dry evaporation can be performed safely and with high efficiency and the dry powder at the outlet can be used. High temperature and high dryness can be maintained. Also, the drying device becomes compact.

Since a high temperature inert gas can be used as a transport medium for the dry sludge dry powder, there is no risk of backfire burning in the pipe, safe operation can be maintained, and the temperature drop in the pipe is small.

Since the sludge dry powder of high temperature and high dryness can be combusted, the ignition is good, the combustion time is short, the high combustion temperature can be obtained, the auxiliary combustion amount can be reduced, and the melt outflow of the smelt can be smoothly controlled. . Also, the combustion melting furnace becomes compact.

Since the temperature of the circulating gas for drying at the outlet of the drying medium gas heater is high, a special heating furnace and fuel for raising the temperature of the circulating gas are unnecessary, and the system is simple and there is a great advantage in terms of energy saving. Is.

A part of the scrubber removal drain is sprayed into the high temperature gas of the secondary combustion furnace, which is effective in reducing NO _X generated by high-load combustion of dry sludge in the melting furnace, and can be made pollution-free. Is.

It becomes possible to control the redox combustion in the sludge combustion melting furnace and the melting temperature of the smelt, and to control the combustion of unburned substances in the secondary combustion furnace and the control of NO _x , which has a large operational margin.

In the secondary combustion furnace, the sludge combustion and melting furnace of the primary furnace, in which the unburned material at the outlet of the sludge combustion and melting furnace of the primary furnace and the extraction gas of the drying medium are charged and the complete combustion is performed, and the high-load combustion is performed the NO _X amount of generation of the internal high-level can be reduced by spraying water vapor drain.

Further, in the case of the constitution of claim 3, it becomes possible to take a long time for the combustion of sludge and the melting and residence time of the inorganic substances and the like, and it is effective when the combustion or the melting does not occur easily in a short time. is there. Further, the melting and smelting of the inorganic matter in the sludge can be smoothly performed by swinging and swinging the sludge combustion and melting furnace main body of the primary furnace.

Further, in the case of the structure of claim 4, the inert gas can be reused, and the amount of new inert gas released from the drying inert gas storage tank can be reduced.
Running costs can be reduced.

Further, in the case of the structure of claim 5, the harmful components contained in the gas vaporized and vaporized by the gas stream dryer can be dissolved in the drain and discharged.

Further, in the case of the sixth aspect, a part of the exhaust gas can be used as a substitute dry gas for the inert gas when the sludge is dried in the airflow dryer.

Further, in the case of the structure of claim 7, a part of the non-condensable gas can be extracted and put into the secondary combustion furnace for complete combustion.

Further, in the case of the structure of claim 8, since the dry sludge is burned by using various adjustable swirl burners, the ignition and combustion in the sludge burning and melting furnace of the primary furnace are good and the high temperature is maintained. The combustion and melting conditions of can be safely maintained.
Further, the melting and smelting of the inorganic matter in the sludge can be smoothly carried out by swirling and swinging the sludge combustion melting furnace main body of the primary furnace together with the burner.

Further, in the case of the structure of claim 9, since the combustion air taken from the atmosphere can be heated to a high temperature and supplied to the sludge combustion melting furnace and the secondary combustion furnace, the combustion can be promoted.

Further, in the case of the structure of claim 10, the convection heat transfer surface is controlled by the outlet distribution damper of the convection heat transfer part so that the convection part heat transfer surface is provided in each of the combustion air heater and the drying medium gas heater. Planning and operation according to heat absorption temperature conditions can be performed.

According to the eleventh aspect of the present invention, by using a part of the exhaust gas discharged from the convection heat transfer section main body as a fluid for transporting the dry sludge into the sludge combustion melting furnace, It is possible to smoothly convey the dry sludge into the sludge combustion melting furnace.

Further, in the case of the structure of claim 12, the outlet gas temperature can be controlled, and the convection heat transfer by controlling the convection inlet gas temperature by recirculating exhaust gas to the secondary combustion furnace outlet. It is possible to prevent high temperature damage on the surface.

Further, in the case of the thirteenth aspect, when the smelt falls, the internal pressure rise due to the generation of steam vapor in the sludge recovery seal tank is prevented, and the vapor pressure is extracted by the differential pressure detection controller to extract the vapor gas in the sludge recovery seal tank. The negative pressure is maintained, smelt is prevented from sticking, and stable fluidized dropping and stable cooling and solidification and granulation can be obtained.

[Brief description of drawings]

FIG. 1 is an overall system diagram of a sludge drying and combustion melting system showing an embodiment of the present invention.

FIG. 2A is a side view showing a burner tilt angle adjustment according to an embodiment of the present invention. (B) is a plan view showing the burner tilt angle adjustment according to the embodiment of the present invention.

FIG. 3A is a sectional view taken along the line AA of FIG.
FIG. 1B is a sectional view taken along the line BB of FIG. (C) is Figure 1
FIG. 9 is a cross-sectional view taken along line C-C of FIG. (D) is a sectional view taken along the line D-D in FIG. 1. (E) is a sectional view taken along the line EE of FIG. 1. (F) is a sectional view taken along the line FF in FIG. 1.

FIG. 4 is an overall system diagram of a sludge drying and combustion melting system showing another embodiment of the present invention.

FIG. 5 is a sliring combustion melting furnace swirling swing diagram showing another embodiment of the present invention.

6A is a cross-sectional view taken along the line AA of FIG.
(B) is a sectional view taken along the line BB of FIG. 4. (C) is FIG.
FIG. 9 is a cross-sectional view taken along line C-C of FIG. (D) is a sectional view taken along the line D-D in FIG. 4. (E) is a sectional view taken along the line EE of FIG. 4. (F) is a sectional view taken along the line FF in FIG. 4. (G) is a sectional view taken along the line GG in FIG. 4. (H) is H-H in FIG.
FIG.

FIG. 7 is an overall system diagram of a conventional device.

[Explanation of symbols]

(Figs. 1, 2, 3) 1. Sludge cake entrance 2. Sludge cake mixer 3. Hammer mill 4. Airflow dryer (D / R) 5. Air flow outlet duct 6. Sludge separation cyclone (C / N) 7. Sludge distributor 8. Dry sludge mixer inlet 8a. Dry sludge recirculation supply pipe 9. Dry sludge supply pipe 10. Dry sludge transport pipe 11. Sludge combustion melting furnace / primary furnace (F1) 12. Sludge burner 13. Secondary air box and damper for sludge burner 14. Burner burner (primary furnace) 15. Secondary air box and damper for auxiliary burner 16. Auxiliary fuel supply pipe 17a. Auxiliary control valve 17b. Auxiliary burner main valve 18． Primary furnace outlet Secondary air nozzle 19. Damper for primary air outlet secondary air nozzle 20. Secondary combustion furnace (F ₂ ) 21. Secondary combustion furnace auxiliary combustion burner 22. Secondary air box and damper for auxiliary combustion burner for secondary combustion furnace 23. Drain injection nozzle 24. Recirculation gas nozzle 25. Convection electric heating unit body 26. Partition wall 27. Combustion air heater 28. Dry medium gas heater 29. Convection heat transfer section outlet distribution damper 30. Convection heat transfer section outlet heat exchange inlet duct 31. Air inlet duct 32. High pressure blower 33. Air inlet duct 34. Hot air outlet duct 35. Convection outlet heat exchange inlet duct 36. Heat exchanger (H / E) 37. Heat exchanger outlet duct 38. Exhaust gas scrubber (S / C) 39. Exhaust gas scrubber outlet duct 40. Scrubber outlet Heat exchange inlet duct 41. Heat exchanger outlet exhaust gas duct damper 42. Suction blower 43. Exhaust gas duct 44. Chimney 45. Recirculation blower 46. Recirculation blower duct 47. Recirculation blower damper 48. Exhaust gas scrubber (S / C ₁ ) drain pipe 49. Drain receiving tank 50. Drain discharge pipe 51. Cyclone outlet paper tube 52. Cyclone outlet paper tube blower 53. Paper scrubber (S / C ₂ ) 54. Paper scrubber outlet exhaust pipe 55. Drying medium transport pipe 56. Mist heater 57. Medium control damper 58. Blower for medium circulation 59. Gas heater inlet pipe 60. Gas heater outlet pipe 61. Inert gas storage tank for drying 62. Active gas control valve 63. Inert gas supply pipe for drying 64. Exhaust gas branch duct 65. Exhaust gas branching damper 66. Backup exhaust gas inlet pipe 67. Drain pump 68. Paper scrubbing drain pipe 69. Paper scrubber drain branch pipe 70. Exhaust gas extraction duct for transporting dry sludge 71. Exhaust gas extraction damper for transportation of dry sludge 72. Exhaust gas blower for transporting dry sludge 73. Ejector 74. Medium gas extraction tube 75. Damper for medium gas extraction 76. Medium gas inlet 77. Smelt pool 78. Smelt outlet 84. Sludge recovery seal tank 85. Shutter nozzle 86. Water pool 87. Differential pressure detection controller 88. Inlet damper 89. Vapor blower 90. Vapor gas duct (Figs. 4, 5 and 6) / other embodiments 79 ． Smelt melting auxiliary burner 80. Secondary air box and damper for smelt melting auxiliary burner 81. Expansion joint for connecting duct 82. Expansion joint for burners 83. Expansion joint for secondary air

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[Procedure amendment]

[Submission date] February 16, 1995

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C02F 11/00 N 11/12 ZAB BF 23G 5/00 ZAB 115 Z 5/04 ZAB A 5/16 ZAB B F26B 21/00 K // B09B 3/00 ZAB B09B 3/00 303 H (72) Inventor Yoshinori Toto 26-11 Kitaeicho, Nagasaki Nagasaki Prefecture (72) Inventor Nobuyoshi Morikawa 2 Shiraiwacho Isahaya Nagasaki Prefecture −11

Claims (13)

[Claims] 1. An airflow dryer for drying sludge composed of a mixture of organic matter and inorganic matter containing a large amount of water with a high temperature inert gas is provided, and the organic matter in the sludge dried by the airflow dryer is burned and generated. A sludge combustion melting furnace that melts inorganic substances in the sludge by high-temperature combustion gas in the furnace is installed, and a smelt outlet that separates and extracts inorganic substances from the bottom of the furnace as smelt is installed at the bottom of the sludge combustion melting furnace to separate molten inorganic substances. Provided a secondary combustion furnace that completely burns unburned organic matter contained in the high-temperature exhaust gas after removal,
In order to reduce the NO _X generated in the furnace by oxidizing and removing the malodorous component contained in the drain of a part of the dry removal water vaporized from the sludge at the time of drying in a flash dryer, the dry removal water content A drain injection nozzle for injecting and introducing a part into the secondary combustion furnace is provided facing the inside of the secondary combustion furnace, and a convection heat transfer section main body is provided to convect the combustion exhaust gas of the sludge combustion melting furnace and the secondary combustion furnace, A drying inert gas storage tank for supplying an inert gas to the airflow dryer is provided, and a drying medium gas heater provided in the middle of a passage for supplying the inert gas from the drying inert gas storage tank to the airflow dryer is provided. Arranged in the convection heat transfer section body, the convection combustion exhaust gas in the convection heat transfer section body is used to raise the temperature of the inert gas passing through the drying medium gas heater, and the sludge combustion melting furnace and the secondary Convection transmission from combustion furnace Dry sludge combustion melt processing system, characterized in that a removal device for removing pollution components contained in combustion exhaust gas discharged through the section body. 2. A sludge composed of a mixed component of an organic substance and an inorganic substance containing a large amount of water is dried by a high temperature inert gas, and then the sludge is put into a sludge combustion melting furnace to burn the organic substance in the sludge to generate the sludge. The high-temperature combustion gas in the furnace melts the inorganic substances in the sludge, separates and extracts it as smelt from the bottom of the furnace, and introduces the high-temperature exhaust gas after separation and removal of the molten inorganic substances into the secondary combustion furnace to completely burn the unburned organic matter. Along with measuring the sludge, a part of the dry-removed water vaporized from the sludge when it is dried by the hot inert gas is jetted into the secondary combustion furnace to oxidize and remove the malodorous component contained in the drain with excess oxygen. NO generated in the furnace
A sludge drying combustion melting treatment method characterized in that _X reduction is measured. 3. A sludge combustion / melting furnace main body is made rigid or horizontal and slidable in a conical shape within a range of a predetermined inclination angle from the furnace outlet as a reference point in order to accelerate the melting of inorganic matter in sludge solids. The sludge drying combustion melting treatment system according to claim 1, wherein a combustion melting furnace main body is installed. 4. A drying medium gas heating provided in the middle of a passage for supplying an inert gas from the inert gas storage tank for drying to the inert gas for drying the inert gas, which has been cooled to low temperature by passing through the airflow dryer. The sludge dry combustion melting treatment system according to claim 1, wherein a circulation passage is provided in the upstream passage of the vessel for recirculation. 5. A drying medium gas heating provided in the middle of a passage for supplying the inert gas from the drying inert gas storage tank to the airflow dryer for the inert gas which has been cooled to a low temperature through the airflow dryer. Provide a passage that circulates in the upstream passage of the vessel,
A scrubber is provided in the middle of the circulating passage, a passage is provided for discharging the drain generated in the scrubber to the outside, and the water in the sludge is vaporized and evaporated in the airflow dryer and introduced into the scrubber together with the medium to be removed as drain. A sludge dry combustion melting treatment system as described. 6. A backup passage is provided to circulate a part of the exhaust gas discharged from the convection heat transfer section main body in the middle of a passage for supplying the inert gas from the drying inert gas storage tank to the airflow dryer. The sludge dry combustion melting treatment system according to claim 1, further comprising a line that uses a part of the exhaust gas outlet. 7. A non-condensable component in the medium is concentrated by providing a medium gas extraction pipe branching from a midway of a passage for supplying the inert gas from the drying inert gas storage tank to the airflow dryer and communicating with the secondary combustion furnace. In order to avoid the above, the sludge dry combustion melting treatment system according to claim 1, further comprising a line for extracting a part of the gas, charging the gas into the secondary combustion furnace, and performing complete combustion. 8. A burner for ejecting dry sludge, fuel, combustion air, etc. into the furnace is provided on each side surface of the sludge combustion melting furnace and the secondary combustion furnace so as to generate a swirling flow in the furnace. 2. The sludge dry combustion melting treatment system according to claim 1, wherein a plurality of the sludge drying combustion melting treatment systems are provided so as to be eccentric from the center of the furnace in a plan view, and the tilt angles are variable in the vertical and horizontal directions. 9. A combustion air heater provided in the middle of a passage for supplying combustion air to a sludge combustion melting furnace and a secondary combustion furnace is arranged in the convection heat transfer section main body to burn the combustion air. 2. The sludge dry combustion melting treatment system according to claim 1, wherein a high temperature is passed through an industrial air heater to promote combustion. 10. The inside of the convection heat transfer section main body is partitioned by a partition wall,
In the main body of the convection heat transfer section partitioned by the partition wall, a drying medium gas heater and a combustion air heater provided in the middle of the passage for supplying combustion air to the sludge combustion melting furnace and the secondary combustion furnace. Are installed side by side, and the convection heat transfer section outlet distribution dampers are provided at the outlets of the convection heat transfer section main bodies that are partitioned by the partition wall and installed side by side, and the combustion exhaust gas that passes through the drying medium gas heater and the air heater is The sludge dry combustion melting treatment system according to claim 1, wherein the flow distribution is controlled by a convection heat transfer section outlet distribution damper. 11. An exhaust gas extraction duct for transporting dry sludge, which is branched from a passage for discharging exhaust gas of a main body of a convection heat transfer section and communicates with a passage for sending dry sludge to a sludge combustion and melting furnace, for transporting the dry sludge. The sludge according to claim 1, wherein an ejector is provided at a downstream end of the exhaust gas extraction duct so that a part of the exhaust gas discharged from the convection heat transfer section main body is used as a transport fluid for the dried sludge into the sludge combustion melting furnace. Dry combustion melting processing system. 12. A removal device for removing pollution components contained in combustion exhaust gas is composed of an exhaust gas scrubber, and a heat exchanger for taking measures against white smoke at the scrubber outlet is installed downstream of the exhaust gas scrubber outlet duct. A passage that circulates a portion of the exhaust gas as recirculation gas to the secondary combustion furnace is provided in the middle of the heat exchanger outlet duct where the exhaust gas that has released heat from the exchanger flows down, and the secondary combustion furnace is utilized by using the recirculation gas. The sludge dry combustion melting treatment system according to claim 1, wherein the outlet temperature is controlled. 13. A device for adjusting solidification and granulation of water-cooled or air-cooled smelt separated and extracted from a sludge combustion melting furnace, the pressure inside the sludge recovery seal tank is always lower than the internal pressure of the sludge combustion melting furnace. As controlled by the differential pressure, part of the steam vapor (or gas) generated in the sludge recovery seal tank is extracted and discharged to the exhaust gas scrubber inlet duct, and the sludge recovery seal tank pressure is maintained at a negative pressure. A differential pressure control system that stabilizes the flow.