Waste gas incinerator for secondary mixing of waste gas and air

Abstract

The utility model discloses a waste gas incinerator for secondary mixing of waste gas and air, which relates to the technical field of waste gas incinerators and comprises an incinerator body, a primary air inlet is arranged at the top of the incinerator body, a burner and an annular waste gas distribution device are mounted at the front end of the incinerator body, and a fire damper and a rotational flow plate are mounted in the incinerator body. An annular secondary air distribution device is arranged on the outer ring at the venturi structure of the middle section of the furnace body; according to the waste gas incinerator, waste gas is innovatively scattered into multiple streams to enter the incinerator body, the waste gas is rapidly distributed in air and rapidly away from the explosion limit range, safety is ensured, meanwhile, the air is divided into primary air and secondary air to be mixed with the waste gas, and it is ensured that mixing is more sufficient, and combustion is more complete.

Description

TECHNICAL FIELD

[0001] The utility model belongs to waste gas incinerator technical field, concretely relates to a waste gas incinerator of waste gas and air secondary mixing. BACKGROUND

[0002] Many chemical synthesis devices produce waste gas without oxygen, and for the treatment of these waste gas without oxygen, the first choice of most chemical enterprises is the direct-fired waste gas incinerator with the highest organic matter incineration rate. The organic matter incineration rate of the waste gas incinerator is mainly determined by the furnace incineration temperature, waste gas residence time, waste gas mixing degree and oxygen content of the furnace. For waste gas without oxygen, air needs to be supplied to the furnace to ensure that organic molecules and oxygen molecules are fully combined and cracked into water and carbon dioxide, so the mixing degree of waste gas and air is particularly critical, which relates to whether the organic matter in the waste gas can be completely cracked to meet the emission standard. At the same time, during the mixing of waste gas without oxygen and air, the explosive limit range is entered, and there is an explosion risk under the condition of open flame. Therefore, how to avoid such safety accidents is particularly important.

[0003] At present, many waste gas incinerators for treating waste gas without oxygen cannot well solve the above two problems at the same time. Even if the waste gas incinerator is designed considering the above two problems, it still has defects and needs to be optimized and improved.

[0004] Patent CN 118718786 A discloses a two-stage injection combustible gas and oxygen mixer. The mixer sends oxygen into the mixer main pipe full of combustible gas through the injection hole. This mixing method can not quickly avoid the explosive limit range of combustible gas, which has certain risks. At the same time, although oxygen is uniformly sent into the mixer through the primary and secondary injection holes, there is no further mixing device or special structure treatment with combustible gas, which is difficult to ensure sufficient mixing, and therefore needs to be optimized. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a waste gas incinerator with secondary mixing of waste gas and air to solve the problems in the background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a waste gas incinerator with secondary mixing of waste gas and air, comprising a furnace body, a primary air inlet is arranged at the top of the furnace body, the middle section is a Venturi structure, an annular secondary air distribution device is arranged on the outer ring of the middle section Venturi structure of the furnace body, a burner and an annular waste gas distribution device are installed at the front end of the furnace body, a waste gas inlet is arranged on the annular waste gas distribution device, a plurality of waste gas nozzle devices are arranged on the side surface of the annular waste gas distribution device, a fire baffle and a cyclone plate are installed inside the furnace body, and the burner is in communication with the inside of the fire baffle.

[0007] Preferably, the waste gas nozzle device is composed of a short circuit, a metal hose, a flange, a matched flange, an external connector, an internal connector and a nozzle, one side of the flange is connected with the annular waste gas distribution device through the short circuit and the metal hose, the other side is connected with the nozzle through the internal connector, and the matched flange of the flange is connected with the furnace body through the external connector.

[0008] Preferably, the secondary air distribution device is a circular annular pipeline, and opposite secondary air inlets are arranged on the pipeline.

[0009] Preferably, the annular waste gas distribution device is a circular annular pipeline.

[0010] Preferably, an insulating layer is arranged on the inner wall of the furnace body.

[0011] Preferably, the outer diameter of the fire baffle is 1.5 times of the outer diameter of the burner flame, and the length is 200-300 mm longer than the edge of the primary air inlet.

[0012] Preferably, the angle of the cyclone plate is 30-45°, and the number of blades is 16-24.

[0013] The technical effects and advantages of the utility model are as follows: the waste gas is innovatively scattered into multiple streams by the waste gas nozzles on the annular waste gas distribution device and enters the furnace body, the waste gas flow of each stream is very small, but the speed is very fast, the whole waste gas combustion furnace is in an air-filled state, the waste gas with small flow rate and fast flow speed is quickly and uniformly dispersed in the air after entering the waste gas combustion furnace, and is quickly away from the explosion limit range, meanwhile, the fire baffle is arranged between the waste gas and the burner flame to prevent the waste gas from directly contacting the open flame, and after the waste gas is uniformly mixed with the primary air, the waste gas is contacted with the central flame in a cyclone state through the cyclone plate, so that the safety is ensured.

[0014] In addition, the air is divided into primary air and secondary air, and is respectively sent into the waste gas combustion furnace and is mixed with the waste gas in stages, wherein the primary air is mixed with the waste gas after entering the waste gas combustion furnace, is contacted with the central flame in a cyclone state through the cyclone plate, the secondary air is sprayed into the waste gas combustion furnace through the annular secondary air distribution device, is mixed with the waste gas in a cyclone state, the mixing position is the Venturi section of the furnace body, the waste gas and the air are fully mixed through the structural design of the contraction section, the middle section and the expansion section, so that the organic matter in the waste gas is completely cracked. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a front view of the utility model;

[0016] Figure 2 It is an A view of the utility model;

[0017] Figure 3The B direction view of the utility model;

[0018] Figure 4 The waste gas nozzle device structure schematic view of the utility model;

[0019] In the figure: 1, furnace body; 2, heat preservation material; 3, primary air inlet; 4, combustor; 5, annular waste gas distribution device; 6, waste gas inlet; 7, waste gas nozzle device; 7-1, short circuit; 7-2, metal hose; 7-3, flange; 7-3A, counter flange; 7-4, external connecting pipe; 7-5, internal connecting pipe; 7-6, nozzle; 8, fire baffle; 9, cyclone plate; 10, annular secondary air distribution device; 11, secondary air inlet; 12, corrugated expansion pipe; 13, flange. DETAILED DESCRIPTION

[0020] The specific embodiments of the utility model will be further described below in combination with the drawings. It needs to be explained here that the description of these embodiments is used to help understanding the utility model, but does not constitute the limitation to the utility model. In addition, the technical features involved in each embodiment of the utility model described below can be combined with each other as long as they do not conflict with each other.

[0021] The utility model provides a waste gas and air secondary mixing's waste gas incinerator as Figures 1-4 The oxygen-free waste gas enters the annular waste gas distribution device 5 through the waste gas inlet 6, the annular waste gas distribution device 5 is a circular pipe, and the flow rate of the waste gas in the device is 10-15 m / s. In order to make the waste gas uniformly distributed in the device and avoid the situation that the pressure is large at the waste gas inlet and the pressure is small at the opposite side of the waste gas inlet, a waste gas inlet is arranged at the top and the bottom of the annular waste gas distribution device 5 respectively, and the air is inhaled on both sides at the same time.

[0022] A plurality of evenly distributed waste gas nozzle devices 7 are arranged on the side surface of the annular waste gas distribution device 5. After the waste gas enters the nozzle device, it reaches the nozzle 7-6 through the metal hose 7-2, the flange 7-3 and the internal connecting pipe 7-5 connected with the short circuit 7-1, the short circuit 7-1 is a threaded joint, and is injected into the furnace body 1 at a speed of 40-80 m / s through the injection hole of the nozzle, and the mixing process with the primary air in the furnace body is completed quickly. Since the nozzle 7-6 is a consumable part and needs to be maintained and replaced, the counter flange 7-3A is arranged, the nozzle is connected with the furnace body 1 through the external connecting pipe 7-4, the nozzle is inserted into the internal connecting pipe in the form of inserting the flange, and the flange is sealed, when the nozzle needs to be replaced, the nozzle can be pulled out by disassembling the flange, and the maintenance is simple and convenient.

[0023] It should be noted that the annular exhaust gas distribution device 5 and the exhaust gas nozzle device 7 are made of stainless steel, and the specific type of stainless steel needs to be selected according to the temperature and corrosiveness of the exhaust gas. For low-temperature and non-corrosive exhaust gas, the material is preferably 304, for high-temperature exhaust gas, the material is preferably 310S, and for highly corrosive exhaust gas, the material is preferably duplex steel or higher-grade Hastelloy.

[0024] Primary air enters the furnace body 1 through the primary air inlet 3 and fills the entire furnace cavity. When the exhaust gas without oxygen is injected into the furnace body through the exhaust gas nozzle 7-6 at a speed of 40-80 m / s, it rapidly diffuses in the primary air, thereby instantaneously moving away from the explosive limit of the exhaust gas. In order to prevent the exhaust gas from directly contacting the flame of the burner 4, a fire baffle 8 is provided in the furnace body 1, which is made of a temperature-resistant material 310S, has a diameter of 1.5 times the flame diameter, and a length of 200-300 mm longer than the edge of the primary air inlet. The burner flame burns inside the fire baffle, and the exhaust gas mixes with the air outside the fire baffle. The flow rate of the mixed gas in the furnace body is 10-15 m / s.

[0025] The edge of the fire baffle 8 is provided with a circle of uniformly distributed cyclone plates 9, the angle of which is 30-45°, and the number of blades is 16-24. The flow rate of the mixed gas between the cyclone blades is 40-60 m / s, thereby rapidly and fully completing the mixing. The mixed gas after the cyclone plate flows along the furnace wall in a cyclone manner, thereby forming a low-speed negative pressure zone in the center of the furnace body. The mixed gas enters the negative pressure zone and contacts and mixes with the burner flame, forming a central cyclone flame, which strengthens the flame combustion.

[0026] The above is the mixing and combustion process of the exhaust gas and the primary air. In order to ensure that the organic matter in the exhaust gas is completely cracked, the flue gas after combustion needs to be mixed with secondary air and high-temperature oxidized to meet the conditions of furnace temperature ≥ 750℃, residence time ≥ 1s, oxygen content ≥ 12% and sufficient mixing. Therefore, a Venturi structure and an annular secondary air distribution device 10 are provided in the middle section of the furnace body 1. The secondary air distribution device 10 is a circular ring-shaped pipeline. After the flue gas enters the Venturi section, it first passes through the converging section to strengthen the cyclone state, and then enters the middle section to mix with the secondary air. The secondary air enters the annular secondary air distribution device 10 through the secondary air inlet 11. Similarly, in order to ensure the uniformity of the secondary air in the distribution device, two secondary air inlets are provided. The flow rate of the secondary air in the distribution device is 10-15 m / s, which enters the middle section of the Venturi section through a plurality of corrugated expansion pipes 12 connected with the flange 13. At this time, the flue gas and the secondary air are both in a high-speed turbulent state, and the mixing is completed.

[0027] It should be noted that the annular secondary air distribution device 10 and the corrugated expansion pipe 12 are preferably made of 304, which is considered that the secondary air is generally preheated to 400-600 DEG C and then sent into the furnace 1, so as to save the consumption of waste gas incinerator fuel, therefore, the pipeline connected with the furnace and the annular secondary air distribution device is preferably a corrugated expansion pipe, so as to ensure the elongation of the metal material under the condition of high temperature, and prevent the equipment from being damaged.

[0028] The flue gas after the secondary mixing enters the flared section of the venturi section, the flow rate is reduced and the entire furnace is filled, the organic matter which is not completely cracked in the flue gas is oxidized at high temperature at this place, and is cracked into water and carbon dioxide, this section is called the oxidation section, the flow rate of the flue gas in the oxidation section in the furnace is 5-10 m / s. The angle of the venturi section is preferably 45-55 DEG, and the angle of the flared section is preferably 8-15 DEG.

[0029] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A waste incinerator with secondary mixing of waste and air, comprising a furnace body (1), characterized in that: The furnace body (1) top is provided with a primary air inlet (3), the middle section is a Venturi structure, the outer ring of the middle section Venturi structure of the furnace body (1) is provided with an annular secondary air distribution device (10), the front end of the furnace body (1) is provided with a burner (4) and an annular exhaust gas distribution device (5), the annular exhaust gas distribution device (5) is provided with an exhaust gas inlet (6), the side of the annular exhaust gas distribution device (5) is provided with a plurality of exhaust gas nozzle devices (7), the inside of the furnace body (1) is provided with a fire baffle (8) and a cyclone plate (9), the burner (4) is in communication with the inside of the fire baffle (8).

2. The waste incinerator with secondary mixing of waste and air according to claim 1, characterized in that: The exhaust gas nozzle device (7) is composed of a short circuit (7-1), a metal hose (7-2), a flange (7-3), a matched flange (7-3A), an external connecting pipe (7-4), an internal connecting pipe (7-5) and a nozzle (7-6), one side of the flange (7-3) is connected with the annular exhaust gas distribution device (5) through the short circuit (7-1) and the metal hose (7-2), the other side is connected with the nozzle (7-6) through the internal connecting pipe (7-5), the matched flange (7-3A) of the flange (7-3) is connected with the furnace body (1) through the external connecting pipe (7-4).

3. The waste incinerator with secondary mixing of waste and air according to claim 1, characterized in that: The secondary air distribution device (10) is a circular ring pipeline, the pipeline is provided with opposite secondary air inlets (11), the inner ring of the pipeline is provided with a plurality of corrugated expansion pipes (12), the corrugated expansion pipes (12) are connected with the furnace body (1).

4. The waste incinerator with secondary mixing of waste and air according to claim 1, characterized in that: The annular exhaust gas distribution device (5) is a circular ring pipeline.

5. The waste incinerator with secondary mixing of waste and air according to claim 1, characterized in that: The inner wall of the furnace body (1) is provided with a heat preservation layer (2).

6. The waste incinerator with secondary mixing of waste and air according to claim 1, characterized in that: The outer diameter of the fire baffle (8) is 1.5 times of the outer diameter of the flame of the burner (4), and the length is 200-300mm longer than the edge of the primary air inlet (3).

7. The waste incinerator with secondary mixing of waste and air according to claim 1, characterized in that: The angle of the cyclone plate (9) is 30-45°, and the number of blades is 16-24.

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