JPH0554005B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention involves incomplete combustion of industrial waste in a carbonization tower, converting it into carbonization gas having a high calorific value through thermal decomposition, and completely burning the carbonization gas to generate heat. This paper relates to improvement of the air supply device in the carbonization tower of waste heat recovery equipment that aims to recover heat using an exchanger.

[Technical background of the invention and its problems] In recent years, industrial waste has been increasing steadily, and it has become an urgent need to effectively utilize and dispose of this waste.

To dispose of industrial waste, especially waste tires, waste rubber, laminated paper waste, label printing waste, kraft paper, paper adhesive tape waste, etc., the waste is incinerated and the combustion heat is recovered in a waste boiler. The process generally consists of an industrial waste carbonization device, a carbonization gas combustion device, and a combustion gas heat recovery device (e.g. a waste boiler). A rotary kiln, a multistage furnace, a fluidized bed furnace, a fixed bed furnace, etc. are used as the carbonization device in the waste incineration heat recovery equipment as described above. Among these, rotary kilns, multi-stage furnaces, and fluidized bed furnaces are expensive to construct, and are relatively expensive compared to attached combustion equipment, waste heat boilers, etc., and cannot be used in general small and medium-sized processing equipment. For this reason, fixed-bed carbonization towers are used because they have a robust structure and are inexpensive to construct.

The floor structure of conventional carbonization towers is, for example, in the form of a grate or a perforated plate, and in such carbonization towers, primary air for combustion is supplied from the bottom of the floor through the grid gaps or holes, and is loaded on the top of the floor. The waste is partially combusted, the heat is used to thermally decompose the waste, and combustible volatiles are recovered. However, in such a conventional structure, the ventilation gap may be partially blocked by waste or char, causing a biased flow of air inside the carbonization tower, or waste at the time of input or charcoal after carbonization. The distance that air can reach evenly from the hearth decreases due to the nodules, which not only takes a long time to carbonize the waste and burn the charcoal, but also reduces the concentration of combustible components in the carbonized gas, resulting in There is a problem that the heat recovery rate decreases. Moreover, due to unforeseen circumstances, air cannot pass through a part of the carbonization tower due to the above-mentioned reasons, resulting in non-carbonization waste remaining and some of the waste having to be reprocessed. Sometimes it happens.

[Object of the Invention] The present invention has been made in view of the above circumstances, and its purpose is to provide an air supply device for a carbonization tower that can uniformly supply air throughout the entire region of the carbonization tower during carbonization and charcoal combustion. It's about doing.

[Summary of the Invention] In order to achieve the above object, the present invention provides a carbonization tower surrounded by a cooling water wall with a substantially U-shaped air supply pipe such that its vertical portion is located at the center of the carbonization tower. A cooling water wall that penetrates and is fixed through the cooling water wall and communicates with the cooling water wall is provided around the air supply pipe, and a nozzle that opens into the carbonization tower through the cooling water wall is connected to a vertical portion of the air supply pipe. It is characterized by having a large number of them.

[Embodiments of the Invention] The present invention will be described below based on embodiments shown in the drawings. Fig. 1 is a block diagram of the waste incineration heat recovery equipment, and the reference numeral 2 in the drawing indicates that the aforementioned industrial waste is incompletely combusted in the lower part, and the combustion heat is used to thermally decompose the waste. This is a carbonization tower that recovers volatile volatile matter. Reference numeral 7 denotes a combustion cylinder provided on the downstream side of the carbonization tower to completely burn the carbonization gas by supplying insufficient air to obtain high-temperature combustion gas.
8 is a waste heat boiler as a heat exchanger for recovering the heat retained in high-temperature combustion gas, 9 is an axial flow cyclone,
10 is an induction fan, and 11 is a chimney.

FIG. 2 is a sectional view of the lower part of the carbonization tower in the present invention,
FIG. 3 is a view taken from FIG. 2 in the direction of the arrows. Reference numeral 1 in the drawings indicates a cooling water wall provided surrounding the fireproof wall 12 around the carbonization tower. The water in the cooling water wall is supplied by a water supply pump P, preheated, and used for a waste heat boiler or the like. Reference numeral 13 denotes a hearth section comprising a cooling water channel 14, a hearth air supply pipe 15, a hearth air nozzle 16, and the like. The cooling water channels 14 have an inverted trapezoidal cross section, and are provided in large numbers at required intervals, with both ends communicating with the cooling water wall 1. Hearth air supply pipe 14
is provided to pass through the center of each cooling channel, and one end thereof communicates with a hearth wind box 17 common to each hearth air supply pipe. A large number of hearth air nozzles 16 are provided substantially horizontally at required intervals on the hearth air supply pipe 14, opening into the carbonization tower from the side wall of the cooling waterway that slopes inward. 18
is a carbonization blower installed in communication with the wind box 17. Reference numeral 19 designates a number of charcoal combustion nozzles that are provided at required pitches on the peripheral wall of the carbonization tower above the carbonization tower hearth, and 20 designates a charcoal combustion wind box that surrounds the charcoal combustion nozzles and is provided on the outside of the water tube wall. 21 is a charcoal combustion blower provided in communication with the charcoal combustion wind box. Reference numeral 22 denotes an outlet of the carbonization tower connected to the subsequent combustion cylinder, and a large number of pipes 23 are vertically provided at required intervals at the outlet so as to communicate with the upper and lower cooling water walls. This prevents waste from flowing into the combustion tube. Reference numeral 3 denotes a substantially U-shaped air supply pipe for both carbonization and charcoal combustion, which is inserted vertically from the cooling water wall into the upper part of the hearth, and is installed so that its vertical portion 4 is located at the center of the carbonization tower. . Reference numeral 5 denotes a cooling water pipe that surrounds the air supply pipe 3 located in the carbonization tower and is provided with both ends communicating with the cooling water wall. Reference numeral 6 denotes a number of nozzles for both carbonization and charcoal combustion, which are installed in the vertical portion of the approximately U-shaped air supply pipe in a state that penetrates the cooling water pipe and opens into the carbonization tower. One end of the substantially U-shaped air supply pipe opens into a wind box 24 for both carbonization and charcoal combustion provided outside the cooling water wall, and the wind box 24 communicates with the carbonization blower.
A first damper 25 is inserted between the carbonization blower and the hearth wind box, and a second damper 26 is inserted between the carbonization blower and the wind box shared with the carbonization blower, so that the amount of air can be adjusted. It is composed of

Next, the operation of the above configuration will be explained. first,
A predetermined amount of material to be incinerated is introduced from the top of the carbonization tower.
Also, a predetermined amount of water is supplied to the cooling water wall of the carbonization tower and the waste heat boiler. Next, preheating operation is started, the induction fan is operated, and the combustion tube and waste heat boiler are pre-purged for a set time, and then a burner (not shown) provided in the combustion tube is ignited to preheat the combustion tube. When the combustion temperature reaches, for example, about 700°C, carbonization operation begins. During carbonization operation, a combustion blower (not shown) in the combustion tube is operated while the induction fan and combustion burner are in operation to supply air for carbonization gas combustion to the combustion tube, and a dust removal blower (not shown) is operated. After operation and the axial flow cyclone extraction started,
The waste is ignited through the ignition port (not shown) at the bottom of the carbonization tower. Next, the carbonization blower is operated, air is blown out from the carbonization nozzle, and combustion is started in the carbonization tower floor. The waste is heated to a high temperature by the combustion heat, causing thermal decomposition and generating flammable volatile matter.
When this carbonized gas enters the combustion tube, it mixes with secondary air from the combustion blower, undergoes complete combustion, becomes high-temperature combustion gas, and reaches the waste heat boiler. The exhaust gas, which is cooled by heat exchange in the waste heat boiler, is removed by an axial flow cyclone and discharged out of the system through the chimney. When the combustion temperature of the combustion tube reaches, for example, about 900°C, the heating burner is stopped and a steady state is entered. When the carbonization of the waste at the bottom of the carbonization tower progresses and the temperature of the combustion tube decreases, the charcoal combustion blower is also activated to accelerate the carbonization of the waste at the top. At the same time, the second damper is also opened to equalize the air supply and prevent the occurrence of air unreachable areas. When the carbonization of waste is completed and carbonized, the combustion tube temperature drops to below 200℃. Once the carbonization operation is complete, the waste charcoal combustion operation begins.
Charcoal combustion is performed by operating a charcoal combustion blower and a carbonization blower at the same time. At this time, the first and second dampers are opened to ensure complete charcoal combustion. When charcoal combustion is completed, the remaining ash is scraped out from the ash outlet. For example, perform the above operations in 1
This cycle is repeated once a day to process industrial waste. In addition, in the above embodiment, the case where one approximately U-shaped air supply pipe was provided in the center of the carbonization tower was explained, but the invention is not limited to this, and if the inner diameter of the carbonization tower is large, an approximately U-shaped air supply pipe is provided. As shown in FIG. 4, a plurality of vertical portions of the air supply pipe may be provided concentrically with the fireproof wall.

[Effects of the Invention] Since the present invention has the above-described configuration, it has the following effects.

(1) Since the approximately U-shaped air supply pipe is installed vertically in the center of the carbonization tower, there will be no air-unreachable portions due to bridging caused by solid waste during carbonization and charcoal combustion. Carbonization and charcoal combustion are performed evenly throughout the entire interior of the carbonization tower, eliminating unevenness, shortening dry flow and charcoal combustion periods, and eliminating the generation of untreated waste.

(2) Since the air supply pipe is surrounded by a cooling water pipe, there is no risk of overheating or burnout.

(3) Therefore, it is possible to create a device that does not require special materials, is inexpensive, and can constantly and evenly supply air.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of waste incineration heat recovery equipment, Figure 2
The figure is a cross-sectional view of the lower part of the carbonization tower according to the present invention, FIG. 3 is a view taken along the - arrow in FIG. 2, and FIG. 4 is a cross-sectional view of another embodiment of the present invention. 1... Cooling water wall, 2... Carbonization tower, 3... Air supply pipe, 4... Vertical section, 5... Cooling water pipe, 6...
Nozzle, 7... Combustion tube, 8... Waste heat boiler, 9
... Axial flow cyclone, 10 ... Induction fan, 11
... Chimney, 12 ... Fireproof wall, 13 ... Hearth part, 1
4...Cooling channel, 15...Heart air supply pipe, 16
... Hearth air nozzle, 17 ... Wind box for hearth, 18 ... Carbonization blower, 19 ... Nozzle for charcoal combustion, 20 ... Wind box for charcoal combustion,
21... Charcoal combustion blower, 22... Carbonization tower outlet,
23...pipe, 24...common wind box, 25...first damper, 26...second damper.

Claims (1)

[Claims] 1 A substantially U-shaped air supply pipe 3 is fixed to the carbonization tower 2 surrounded by the cooling water wall 1 by penetrating the cooling water wall 1 so that its vertical portion 4 is located at the center of the carbonization tower 2. Furthermore, a cooling water wall 5 communicating with the cooling water wall 1 is provided around the air supply pipe 3, and a number of nozzles 6 that open into the carbonization tower through the cooling water wall 5 are provided in the vertical portion 4 of the air supply pipe. An air supply device for a carbonization tower in a waste incineration heat recovery facility.