JPH04108130U - Combustion gas mixing structure in garbage incinerator - Google Patents

Abstract

(57) [Summary] [Configuration] A grate-type waste incinerator equipped with a primary combustion chamber (1) equipped with a grate (7) and a secondary combustion chamber (2) connected above it. This is a combustion gas mixing structure in a waste incinerator, characterized in that a partition (11) is provided at the outlet of the primary combustion chamber (1) to divide the combustion gas flow. [Effect] The combustion gases rising inside the primary combustion chamber are divided by the partitions and then merged above the partitions, causing collisions between the combustion gases. Therefore, a vortex is generated and the combustion gas is well mixed, and the flame, unburned matter, and surplus air are efficiently mixed, and complete combustion is promoted. As a result, the unburned content in the exhaust gas containing dioxin precursors such as hydrocarbons is drastically reduced, the generation of dioxin is prevented, and exhaust gas containing very little or no dioxin can be released into the atmosphere.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea relates to garbage incinerators used for incinerating municipal waste, industrial waste, etc. More specifically, we are developing a new structure for combustion furnaces that effectively mixes the combustion gas inside the furnace. It is related to

0002

[Conventional technology]

A conventional grate-type waste incinerator has a primary combustion chamber equipped with a grate (7), as shown in Figure 7. An inverted U-shape is formed by a partition wall (9) above the combustion chamber (1) and the primary combustion chamber (1). A secondary combustion chamber (2) and a gas exhaust system that guides the combustion gas generated in the secondary combustion chamber (2) to the flue (3). Exhaust heat recovery device installed near the flue (3) in the exit path (4) and the gas exhaust path (4) (5) and an exhaust gas cooling heat exchanger (6). At the entrance of the secondary combustion chamber (2) is equipped with a secondary air supply nozzle (8). The garbage (R) in the hopper (10) is at fire level. It is placed on top of the grate (7) and is combusted by the primary air supplied from below the grate (7). Secondary air is supplied to the secondary combustion chamber (2) from the secondary air supply nozzle (8). Ru.

0003 The combustion gas generated by incinerating the garbage (R) is shown by the solid line and the solid line in Figure 7. As shown by the dotted lines, the secondary combustion rises from the primary combustion chamber (1) and goes almost straight. Enter the chamber (2), pass through the gas exhaust path (4), and pass through the exhaust heat recovery device (5) and heat exchanger (6). After being cooled, it is discharged from the flue (3) and sent to an exhaust gas treatment device (not shown). It looks like this.

0004

[Problem that the idea aims to solve]

However, when incinerating waste using the above-mentioned incinerator, the following problems arise. There is.

[0005] In other words, the combustion gas from the primary combustion chamber (1) rises as described above and becomes almost stressed. Because the combustion gas enters the secondary combustion chamber (2) at the Unburnt substances such as carbon atoms, hydrocarbons, and soot are likely to be generated.

[0006] In addition, the combustion gas from the primary combustion chamber (1) rises through the ascending path of the secondary combustion chamber (2), Then, while descending from the top down the descending path, the temperature drops. Outlet of primary combustion chamber (1) Temperature increases the risk of clinker formation due to ash melting, shortened refractory life, grate burnout, Due to problems such as the generation of NOx, it is not possible to raise the temperature to over 1000°C, which is suitable for combustion. The temperature is usually kept below 900°C.

[0007] Therefore, the secondary combustion chamber (2) has a residence time of 2 seconds or more for the purpose of complete combustion. However, the gas temperature decreases as it moves downstream. By nozzle (8) Even if secondary air is supplied to the inlet of the secondary combustion chamber (2), this air will not mix with the combustion gas. When reaching the oxidation region, the oxidation reaction slows down because the gas temperature has decreased as described above. complete combustion is difficult to achieve. As a result, carbon monoxide, hydrocarbons, and soot The unburned components such as these will be emitted as is along with the combustion exhaust gas.

[0008] Additionally, the gas flow in the secondary combustion chamber (2) is close to the so-called piston flow. , the combustion of garbage changes depending on the amount of input garbage, fluctuations in calorific value, changes in the form of garbage, etc. It fluctuates suddenly, often resulting in a momentary air shortage, and in this case too. Unburned substances such as carbon monoxide, hydrocarbons, and soot are emitted along with the exhaust gas. this field The reason is that in piston flow gas flow, the upstream combustion gas and downstream combustion gas mix. This is due to the fact that the above-mentioned momentary air shortage condition occurs because the air conditioner is not maintained.

[0009] Hydrocarbons contained in large amounts in exhaust gas are so-called dioxin precursors. A substance that reacts with chlorides such as hydrogen chloride gas in the wake, producing highly toxic dioxin. There is a problem in generating .

0010 The purpose of this invention was to solve the above problems and to dispose of municipal waste and industrial waste in waste incinerators. Providing a garbage incinerator that can prevent the generation of unburned materials when incinerating waste, etc. It's about doing.

[0011]

[Means to solve the problem]

This idea was devised to achieve the above purpose, and the primary combustion chamber outlet Combustion gases can be mixed effectively by installing specific components in the This was completed based on this knowledge.

0012 In other words, this idea consists of a primary combustion chamber equipped with a grate and a combustion chamber connected above it. In a grate-type waste incinerator equipped with a secondary combustion chamber, a combustion gas is installed at the outlet of the primary combustion chamber. Combustion in a waste incinerator characterized by a partition that separates the waste flow. It has a combustion gas mixed structure.

[0013] In a preferred embodiment of this invention, a secondary air supply nozzle is provided near the partition. is installed.

[0014] The combustion gas temperature in the secondary combustion chamber is preferably in the range of 1000 to 800°C. Ru.

[0015]

[Effect]

In the waste incinerator of this design, the combustion gas flow is diverted to the outlet of the primary combustion chamber. Since the combustion gas flow rising inside the primary combustion chamber is After being separated by the partition, they merge above the partition, causing collisions between the combustion gases. Ru. As a result, a vortex is generated and the combustion gases are well mixed, and the flame and unburned components are and surplus air are mixed efficiently and complete combustion is achieved.

[0016]

【Example】

Next, this invention will be specifically explained with reference to illustrated embodiments. In addition, in context Therefore, the left side of FIG. 1 will be referred to as the front.

[0017] In Figure 1, the waste incinerator according to this invention has a primary combustion chamber equipped with a grate (7). (1), a secondary combustion chamber (2) connected above the primary combustion chamber (1), and a primary combustion chamber (1). The hopper (10) leading to the It is equipped with a secondary air supply nozzle (8). Furthermore, at the outlet of the primary combustion chamber (2), A triangular prism-shaped partition (11) with a nearly horizontal bottom is provided to divide the combustion gas flow. Ru.

[0018] The garbage (R) in the hopper (10) is removed by the primary air supplied from below the grate (7). The secondary combustion chamber (2) is supplied with secondary air from the secondary air supply nozzle (8). be provided.

[0019] In the above configuration, the combustion gas rising inside the primary combustion chamber (1) is directed through the partition (11). The flow is changed forward and backward when it hits the bottom of the After that, it rises along the side of the partition (11). The forward flow and backward flow are arranged above the partition (11). The combustion gases merge at the point where the combustion gases collide with each other. As a result, a vortex is created and the combustion gas is Mix well.

[0020] The secondary air supply nozzle (8) is located slightly above the partition (11), and is Mixing of combustion gases by supplying secondary air to the location where gas collisions occur will be further promoted.

[0021] Figures 2, 3, 4, 5 and 6 show modified examples of the partition of this invention. be.

[0022] First, in the example in Figure 2, the partition (12) is connected to the vertical part (12a) and the upper end of the vertical part (12a). and a forwardly inclined bent portion (12b). In this configuration, the primary combustion chamber (1) The combustion gas flow rising from the top is divided into a forward flow and a backward flow by the vertical part (12a). , the forward flow hits the bend (12b) and is diverted forward, then rises and flows backward. The flow rises straight along the vertical section (12a). The forward flow and backward flow are separated by a partition (1 2) The combustion gases merge at the top and collide with each other. As a result, a vortex is created and the combustion gas mix well. Further, secondary air may be supplied as necessary.

[0023] In the example shown in Figure 3, the partition (13) is continuous with the vertical part (13a) and the upper end of the vertical part (13a), and It consists of a bent part (13b) that is inclined towards the side. In this configuration, the air rises inside the primary combustion chamber (1). The combustion gas flow that has been generated is divided into a forward flow and a backward flow by the vertical part (13a), and the The flow hits the bend (13b) and is redirected backwards before rising, and the forward flow becomes vertical. It rises straight along the straight part (13a). The forward flow and backward flow are arranged above the partition (13). The combustion gases meet and collide with each other. As a result, a vortex is created and the combustion gas is Mixed. Further, secondary air may be supplied as necessary.

[0024] In the example in Fig. 4, the partition (14) is connected to the vertical part (14a) and the lower end of the vertical part (14a), and It consists of a bent part (14b) that is inclined towards the side. In this configuration, the air rises inside the primary combustion chamber (1). The combustion gas flow hits the bend (14a) and is changed direction, After being divided into a forward flow and a backward flow, it rises. The forward flow and backward flow are arranged above the partition (14). The combustion gases meet and collide with each other. As a result, a vortex is created and the combustion gas is Mixed. Further, secondary air may be supplied as necessary.

[0025] In the example in Figure 5, the partition (15) is connected to the vertical part (15a) and the lower end of the vertical part (15a) and It consists of a bent part (15b) that is inclined towards the opposite direction. In this configuration, the air rises inside the primary combustion chamber (1). The combustion gas flow hits the bend (15b) and is changed direction, It is divided into a forward flow and a backward flow and rises. The forward flow and backward flow meet above the partition (15). Collision between flowing combustion gases occurs. As a result, a vortex is created and the combustion gases are mixed well. be given Further, secondary air may be supplied as necessary.

[0026] In the example in Figure 6, the partition (16) is an inverted V-shape that connects the vertical part (16a) and the lower end of the vertical part (16a). It consists of a shaped bent part (16b). In this configuration, the air has risen inside the primary combustion chamber (1). The combustion gas flow hits the bend (16b) and is changed in direction, and is separated from the forward flow. After being diverted into the backward flow, it rises. The forward flow and backward flow meet above the partition (16). Collisions between combustion gases occur. As a result, a vortex is created and the combustion gases are not mixed well. It will be done. Further, secondary air may be supplied as necessary.

[0027] When the combustion gases are well mixed in this way, the flame and unburned gas are mixed with excess air. is carried out efficiently, and unburned substances such as carbon monoxide, hydrocarbons, and soot are completely removed in the vortex. It is burned and the combustion is completed very quickly.

[0028] Also, carbon monoxide and hydrocarbons coming from the momentary air shortage caused by piston flow. Emissions of unburned substances such as soot and soot can be drastically reduced as a result of sufficient mixing of combustion gases. It will be done.

[0029] CO concentration at each point in the incinerator with and without supplying secondary air The measured results are shown in Table 1 below. However, the secondary combustion at this time The inlet temperature of the chamber is maintained in the range of 950-900°C.

[0030]

[Table 1]

[0031]

[Effect of the idea]

According to the waste incinerator of this invention, the combustion gas flow is diverted to the outlet of the primary combustion chamber. Since a partition is provided, the combustion gas rising inside the primary combustion chamber is After being separated by the flow, they merge above the partition, causing a collision between the combustion gases. did Therefore, a vortex is generated and the combustion gas is well mixed, and the flame, unburned matter, and surplus are separated. Mixing with surplus air is performed efficiently and complete combustion is promoted. As a result, hydrocarbon water The amount of unburned matter in the exhaust gas containing dioxin precursors such as Preventing the generation of dioxin and producing exhaust gas that contains very little or no dioxins. Can be released into the atmosphere.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing one specific example of a garbage incinerator according to the invention.

FIG. 2 is a vertical cross-sectional view of the essential parts of a specific example of the garbage incinerator according to the invention.

FIG. 3 is a vertical cross-sectional view of a main part of a specific example of the garbage incinerator according to the invention.

FIG. 4 is a vertical cross-sectional view of a main part of a specific example of the garbage incinerator according to the invention.

FIG. 5 is a vertical cross-sectional view of a main part of a specific example of the garbage incinerator according to the invention.

FIG. 6 is a vertical sectional view of a main part of a specific example of the garbage incinerator according to the invention.

FIG. 7 is a vertical sectional view showing a conventional garbage incinerator.

[Explanation of symbols]

(1) ...Primary combustion chamber, (2) ...Secondary combustion chamber, (7) …Grate; (11)(12)(13)(14)(15)(16)...Partition.

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Tadashi Kono Hitachi, 5-3-28 Nishikujo, Konohana-ku, Osaka Within Shipbuilding Co., Ltd. (72) Creator Kohei Hamabe Hitachi, 5-3-28 Nishikujo, Konohana-ku, Osaka Within Shipbuilding Co., Ltd. (72) Creator Kazuo Ieyama Hitachi, 5-3-28 Nishikujo, Konohana-ku, Osaka Within Shipbuilding Co., Ltd. (72) Creator Mamoru Kondo Hitachi, 5-3-28 Nishikujo, Konohana-ku, Osaka Within Shipbuilding Co., Ltd.

Claims (1)

[Scope of utility model registration request] [Claim 1] A primary combustion chamber (1) equipped with a grate (7);
In a grate-type waste incinerator equipped with a secondary combustion chamber (2) connected above the primary combustion chamber (1), there are partitions (11) (12) ( 13)(14)(15)(16) A combustion gas mixing structure in a garbage incinerator.