JPH06218397A - Method and device for drying and firing sludge - Google Patents

Abstract

PURPOSE:To heat a cake uniformly over every part thereof efficiently in a short time by forming a cake prepared by removing water from sludge into a thin piece so that the water therein can be vaporized, and thereafter drying the cake in the form of a thin piece while it is being carried through a heated oil tank. CONSTITUTION:A cake K prepared at a sludge dewatering machine 1 is carried to a cake storage tank 3 and transferred then to a hopper 5a of a cake thickness forming machine 5 by means of a cake transfer pump 4. The hopper 5a includes a pair of inwardly rotating rolls 5b at the lower part thereof, and by properly adjusting the gap between the rolls corresponding to water content and properties of the cake, the cake K is formed into a thin piece having an optimum thickness. And an oil tank 7 is installed under the machine 5, and the cake K is moved through oil having been heated at a heating section 6 by means of a heating means toward an outlet to remove moisture from the cake K, which cake is then stored in a fry storage tank 12 via a guide plate 11.

Description

Detailed Description of the Invention

[0001]

[Field of Industrial Application] The present invention coagulates and sediments wastewater discharged from various manufacturing factories such as a pulp and paper factory, a food manufacturing factory and kitchen-related facilities such as hotels, lunch facilities and restaurants, and sewage and night soil treatment plants. Floating separation, biological treatment, and other various treatments to obtain sludge (sludge), and then dehydration of the sludge with a dehydrator, and a method for drying and incinerating sludge mainly for cakes obtained Regarding the device.

[0002]

2. Description of the Related Art As a conventional method for treating organic sludge of this type, a flammable oil is heated to a temperature higher than the boiling point of water, and sludge-like organic sludge is added to the oil for dehydration and solidification. ,
There is a method of burning the solidified sludge together with the attached flammable oil (see Japanese Patent Application Laid-Open No. 50-139574).

[0003]

However, in the above-mentioned conventional organic sludge treatment method, the sludge-shaped organic sludge having a high water content is directly added to oil without further dehydration of the sludge-shaped organic sludge by a dehydrator. Therefore, it was not practical because the drying efficiency was poor. Also, if the cake obtained by dehydrating sludge (sludge) with a dehydrator is directly put into an incinerator without being dried, the water content in the cake is too high, and a large amount of fuel is consumed. ineffective.

Generally, there are various types of dehydrators, but the thickness of a cake obtained by using a belt press or a filter press is as thick as 5 to 20 mm. Therefore, even if a cake having such a thickness is put into a heated oil tank, the central portion of the cake does not dry well, and it takes a long time to dry and the drying efficiency is poor. Further, even if a round and large dango-shaped cake obtained by using a centrifugal dehydrator or a screw press is put into an oil tank, the inside of the cake does not dry. Further, when the cake dehydrated by the dehydrator is stored in the cake storage tank, the cake is compacted by its own weight in the storage tank to form a large lump, which is also difficult to dry.

The present invention has been made in view of the above points, and an object of the present invention is to form a cake into a flaky form, to uniformly and efficiently dry any part in a short time, and to provide a cake after drying. It is an object of the present invention to provide a method and an apparatus for drying and incinerating sludge that can be efficiently incinerated with less fuel. Also, even if the cake obtained from the dehydrator is a thick cake or a large dango-shaped mass, or even if the cake is compacted by its own weight into a large mass in the storage tank, Loosen the cake mass,
Allows the cake to be sent out to the average while easily obtaining the desired flaky shape with a simple structure, and moves the cake in an oil tank to force thermal contact for quick and continuous drying. It is to provide a drying and incineration device for the sludge that has been soaked.

[0006]

The method for drying sludge according to the present invention is a method in which a cake obtained by dehydrating sludge is formed into flakes capable of evaporating water, and then the flaky cake is heated in an oil tank. It is designed to be dried while being transported inside. Further, the sludge drying device according to the present invention includes a dehydrator that dehydrates sludge into a cake, a cake thickness molding machine that forms the cake into a flaky shape having a predetermined thickness, and conveys a flaky cake in oil. And an oil tank equipped with a scraper. Further, the method for drying and incinerating sludge according to the present invention is to dehydrate the sludge to obtain a cake having a water content of 90% or less, then form the cake into a water-evaporable flaky cake, and then form the flaky cake. The dried cake is dried while being conveyed in a heated oil tank, and the dried cake is incinerated. Further, the sludge drying and incineration apparatus according to the present invention, a dehydrator for dehydrating sludge into a cake, a cake thickness forming machine for forming the cake into a flaky shape having a predetermined thickness, and a flaky shape in oil. It comprises an oil tank equipped with a scraper for conveying the cake, and an incinerator for incinerating the cake dried in the oil tank.

Further, the sludge drying and incinerating apparatus according to the present invention comprises a dehydrator for dehydrating sludge into a cake, a cake storage tank for storing the cake obtained by the dehydrator, and a cake for the storage tank. To a hopper, and a cake thickness molding machine with a built-in leveling vane that loosens the cake mass in the hopper and sends the cake to the average, and a flaky cake obtained by the molding machine as an oil. It is composed of an oil tank equipped with a scraper to be conveyed inside, and an incinerator for incinerating the cake dried in the oil tank. Furthermore, the cake thickness molding machine is equipped with a pair of inwardly rotating rolls or extrusion die.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic explanatory view of a sludge drying and incinerating apparatus showing an embodiment of the present invention. 1 may be a sludge dewatering machine, or any of pressure dewatering, vacuum dewatering, centrifugal dewatering, roll dewatering, or a combination thereof depending on the treated sludge. 2 is the cake K obtained from the sludge dewatering machine 1 in the next cake storage tank 3
It is a conveyor to be transferred to. The cake storage tank 3 is provided because the distance to the oil tank 7 described later is long,
It is suitable as a temporary storage place when there is not enough space for installing the dehydrator 1 or the like around the oil tank 7. Further, when the cake storage tank 3 is installed, the cake K can be stored, so that the operation time can be adjusted. However, the cake K obtained by the sludge dewatering machine 1 is directly provided without providing the cake storage tank 3, and the hopper 5 of the cake thickness molding machine 5 described later is used.
You may make it throw into a.

Reference numeral 4 is a cake transfer pump for transferring the cake K in the cake storage tank 3 to the hopper 5a, which is carried out by a pipeline. Reference numeral 5 denotes a leveling blade incorporated in the hopper 5a, which serves to loosen the cake K in the hopper 5a and send the cake K to the average. The cake thickness molding machine 5 equipped with a hopper 5a is equipped with a pair of inwardly rotating rolls 5b at the bottom of the hopper 5a, and the gap between the pair of rolls 5b is adjusted according to the moisture content and properties of the dehydrated cake. By adopting a structure that can be adjusted as appropriate, a thin piece having an optimum thickness is formed. For example, the thickness of the flaky cake K extruded from the roll 5b is 0.
Molding from 5 mm to several mm enables efficient drying in an oil tank. Further, the rotation speed of the roll 5b can be changed so that the discharge speed of the cake K can be adjusted. The thin piece shape in the present invention is not limited to a thin piece, and includes various shapes such as a sheet shape, a strip shape, a ribbon shape, or a strip shape such as a udon shape, and the point is that the drying in an oil tank is even to the inside of the cake. Any shape can be used as long as it is performed in a short time.

In FIG. 1, the cake thickness molding machine 5 is configured to use a pair of inwardly rotating rolls 5b, but the invention is not limited to this, and as shown in FIG. May be extruded in the form of flakes. That is, the cake K transferred into the hopper 5a sealed by the cake transfer pump 4 is
You may make it extrude from the base 5c provided in the lower part of a. The base 5c can be replaced or the thickness can be adjusted so that the cake K having the optimum thickness is discharged. In this example, the case where the hopper 5a is a closed type and the cake K is pumped is described.
The cake K may be extruded into a thin piece by a cylinder method (not shown) or the like.

Below the cake thickness forming machine 5, an oil tank 7 having a side surface ship shape or a plane rectangular shape is installed. Sprockets 8 for driving an endless chain 9 are provided at both outer ends in the longitudinal direction of the oil tank 7. Attached to the endless chain 9 is a scraper 10 that moves from the inlet to the outlet along the longitudinal direction in the oil tank 7 at a predetermined interval, and the flaky cake K charged in the oil tank 7 is attached by the scraper 10. Move to the exit side while scraping them one by one. The scraper 10 is provided with a large number of holes (not shown) through which the oil passes, in order to prevent the oil in the oil tank 7 from undulating during transfer, or the scraper 10 itself is formed in a wire mesh shape. Further, in the scraper 10, the rotation of the sprocket 8 meshing with the chain 9 is changed so that the immersion time of the cake K can be changed so that the moving speed of the scraper 10 can be adjusted.

As the oil filled in the oil tank 7, waste oil such as used cooking oil is used in order to reduce the cost. The oil in the oil tank 7 is heated by the heating section 6 by a gas burner, kerosene combustion or other heating means to a temperature at which the water contained in the flaky cake K can be evaporated.
It is preferable to heat to a temperature of about 0 ° C to 200 ° C. Oil tank 7
A fire extinguishing liquid spray nozzle 11 is installed at a plurality of locations above the, and equipment for automatic extinguishing is provided in case of emergency such as when the oil in the oil tank 7 spontaneously ignites. The flaky cake K charged into the oil tank 7 is heated by the scraper 10 in the heated oil in order, and the water in the cake K is moved by the heated oil in the process of moving to the outlet side while being scraped. Evaporate and dry. That is, since the cake K is not brought into contact with the heated oil in a stationary state, the cake K is moved in the oil to forcibly make thermal contact.
The water content in the cake K after drying, which can be dried more quickly, is 5% or less, and the drying efficiency is good. After passing through the oil tank 7, the flaky cake K is successively conveyed by the scraper 10 and is drained to some extent through the periphery and holes of the scraper 10 and stored in the fry storage tank 12 via the guide plate 11.

The dried cake L stored in the fry storage tank 12 is conveyed by the screw conveyor 13 to the incinerator 14.
Be thrown into. The cake L after drying, which has been put into the incinerator 14, contains oil in the cake itself, and this serves as an auxiliary fuel, which can be combusted more effectively due to the combustion heat in the incinerator 14 and the dust. It has extremely low water content, can burn quickly, and has good fuel efficiency.

Example 1 Cake K having a water content of 85% dehydrated by a sludge dewatering machine 1
Is charged into the hopper 5a, the gap between the rolls 5b of the cake thickness molding machine 5 is set to 2 mm, and the flaky cake K extruded from the rolls 5b of the cake thickness molding machine 5 is heated at a temperature of 180 ° C. in the oil tank 7. The water content of the cake L after being immersed in oil and dried by the scraper 10 for 3 minutes while moving the cake K in the oil was 5%. Example 2 Cake K having a water content of 85% dehydrated by the sludge dehydrator 1
Is charged into the hopper 5a, the gap between the rolls 5b of the cake thickness molding machine 5 is set to 1 mm, and the flaky cake K extruded from the rolls 5b of the cake thickness molding machine 5 is heated at a temperature of 180 ° C. in the oil tank 7. The water content of the cake L after being immersed in oil and dried for 2 minutes while moving the cake K in the oil with the scraper 10 was 1%.

Comparative Example 1 Dewatered by the sludge dewatering machine 1 and having a water content of 85% and a thickness of 5 m
m cake K directly as it is, the temperature in the oil tank 7 is 180 ° C.
The water content of Cake L is 40% after dipping for 5 minutes while moving Cake K in oil with scraper 10 while moving it in oil, and the surface of the cake is dry, but the inner side is not dry explosion. It was For this reason, incineration in an incinerator was incomplete.

[0016]

As can be seen from the above description, the present invention forms a cake obtained by dehydrating sludge into a water-evaporable flaky cake, and then transports the flaky cake in a heated oil tank. However, since it was decided to dry it, it was not possible to form the cake into thin flakes and to move the cake in heated oil to forcibly make thermal contact. It is even and can be efficiently dried in a short time. In addition, the cake after drying contains oil in the cake itself, which serves as an auxiliary fuel, and can be burned more effectively in combination with the heat of combustion in the incinerator, resulting in a very small amount of water and quickness. In addition to being able to burn, it has good fuel efficiency and can significantly reduce waste. Furthermore, even if the cake obtained from the dehydrator is a thick cake, or a large dango-shaped cake, or even if the cake is compacted by its own weight into a large cake in the storage tank. The cake can be easily obtained in a desired flaky shape with a simple structure while loosening the cake mass and feeding the cake evenly.

Furthermore, the sludge drying and incineration apparatus according to the present invention comprises a dehydrator for dehydrating sludge into a cake, a cake thickness forming machine for forming the cake into a flaky shape having a predetermined thickness, and an in-oil medium. Automatic operation is possible as a series of systems consisting of an oil tank equipped with a scraper for conveying flaky cakes and an incinerator for incinerating cakes dried in the oil tank. Further, the cake thickness molding machine can easily form the cake into a desired flaky shape with a simple structure using a pair of inwardly rotating rolls or an extrusion die. Furthermore, since the hopper of the cake thickness molding machine is equipped with leveling blades, this cake can be loosened even if the cake in the hopper is clumped like a dango, and the cake is sent to the thickness molding location side on average. be able to.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a sludge drying and incineration apparatus showing an embodiment of the present invention.

FIG. 2 is a schematic explanatory view showing another embodiment of the cake thickness molding machine.

[Explanation of symbols]

 1 Sludge Dewatering Machine 3 Key Storage Tank 4 Key Transfer Pump 5 Key Thickness Forming Machine 5a Hopper 5b Roll 5c Clasp 7 Oil Tank 10 Scraper 14 Incinerator K Key L Dry Case Ki

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kuniaki Imao 2-3-8 Nihonbashi, Chuo-ku, Tokyo Nakawa Kiko Co., Ltd. (72) Inventor Daiwa Yuyama 2-chome, Nihonbashi, Chuo-ku, Tokyo No. 3-18 Chuwa Kiko Co., Ltd.

Claims (6)

[Claims] 1. A cake obtained by dehydrating sludge is formed into a flaky thickness capable of evaporating water, and then the flaky cake is dried while being transported in a heated oil tank. Sludge drying method. 2. A dehydrator for dehydrating sludge into a cake,
A sludge drying device comprising a cake thickness forming machine for forming the cake into a flaky shape having a predetermined thickness and an oil tank provided with a scraper for transporting the flaky cake in oil. 3. The sludge is dehydrated to obtain a cake having a water content of 90% or less, the cake is formed into a water-evaporable flaky piece, and the flaky cake is then conveyed in a heated oil tank. A method for drying and incinerating sludge, which comprises drying while incinerating the dried cake. 4. A dehydrator for dehydrating sludge into a cake,
A cake thickness forming machine for forming the cake into a flake shape having a predetermined thickness, an oil tank equipped with a scraper for conveying the flake cake in oil, and an incinerator for incinerating the cake dried in the oil tank. A sludge drying and incinerating device. 5. A dehydrator for dehydrating sludge into a cake,
A cake storage tank for storing the cake obtained by the dehydrator,
A cake transfer pump for transferring the cake in the storage tank to a hopper, a cake thickness molding machine having a built-in leveling blade for loosening the cake lump in the hopper and sending the cake evenly, and a thin piece obtained by the molding machine. An apparatus for drying and incinerating sludge, comprising an oil tank equipped with a scraper for transporting a cake in the form of oil, and an incinerator for incinerating the cake dried in the oil tank. 6. The sludge forming machine according to claim 2, 4 or 5, wherein the cake thickness molding machine according to claim 2, 4 or 5 is provided with a pair of inwardly rotating rolls or an extrusion die. Drying and incineration equipment.