Denitration VOC (volatile organic compound) integrated device

Abstract

The utility model provides a denitration VOC (volatile organic compound) integrated device which comprises a combustion chamber and a plurality of heat storage chambers communicated with the combustion chamber, an air inlet branch pipe, an exhaust branch pipe and a purging branch pipe are arranged at the bottom of the heat storage chamber; a low-nitrogen combustor is arranged at the top of the combustion chamber; a first-stage heat accumulator, a reducing agent spraying opening, an SCR device and a second-stage heat accumulator are sequentially arranged in the heat accumulation chamber from top to bottom; scavenging valves are arranged on the air inlet branch pipe and the exhaust branch pipe; according to the integrated RTO device disclosed by the utility model, denitration VOC is integrated into the integrated RTO device, so that the occupied area is saved; mutual abrasion between the catalyst and the heat storage bricks is avoided; the overall service life of equipment is prolonged; the low-nitrogen combustor reduces NOX generation from the source, the catalyst load of the SCR module is reduced, the catalyst activity attenuation rate is slowed down, the ammonia escape rate is effectively reduced, and secondary pollution is avoided.

Description

Technical Field

[0001] This utility model relates to the field of waste gas treatment technology and equipment, and in particular to an integrated denitrification and VOC removal device. Background Technology

[0002] In industrial production, VOCs and NO are commonly found together in the exhaust gases emitted by industries such as chemical processing and coating. X Both are key air pollutants under control. VOCs contribute to ozone and photochemical smog and are toxic and carcinogenic. NO... X It is a major cause of acid rain and smog, and poses a significant threat to the ecological environment and human health.

[0003] In traditional governance, VOCs and NO X The use of separate subsystems for treatment has obvious drawbacks: while RTOs for VOCs can oxidize and decompose VOCs at high temperatures, they cannot solve the problem of NO in the original waste gas. X NO or secondary NO generated during the combustion of nitrogen-containing organic matter X , handling NO X SCR requires a separate reaction system and an external heat source to maintain the reaction temperature, resulting in high energy consumption. The independent equipment, piping, and control systems of the subsystems lead to overall complexity, large footprint, high investment and operating costs, and energy waste. Existing integrated VOC denitrification devices mostly employ a method of spraying a reducing agent inside the burner and coupling the catalyst with the heat storage bricks. This method not only easily leads to high catalyst loss and damage, but the reducing agent sprayed in the combustion chamber (mostly ammonia) is also prone to excess, causing ammonia escape and reacting with some components in the exhaust gas to produce byproducts that clog the catalyst micropores, ultimately leading to catalyst failure. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing an integrated denitrification and VOC removal device.

[0005] To achieve the above objectives, this utility model adopts the following technical solution: an integrated denitrification VOC device, comprising a combustion chamber and multiple regenerator chambers connected to the combustion chamber; the combustion chamber is located above the regenerator chamber; each regenerator chamber has an intake branch pipe, an exhaust branch pipe, and a purge branch pipe at its bottom; the intake port of each intake branch pipe is connected to the waste gas to be treated and an induced draft fan through an intake main pipe, and the intake main pipe is equipped with an exhaust valve and an intake master valve; each exhaust branch pipe is connected to a chimney through an exhaust main pipe, and each purge branch pipe is connected to a purge fan through a purge main pipe; the purge branch pipe is equipped with a purge valve; a low-NOx burner is provided at the top of the combustion chamber; each regenerator chamber, from the upper part near the combustion chamber to the lower part, is sequentially equipped with a primary regenerator, a reducing agent spray port, an SCR device loaded with a denitrification catalyst, and a secondary regenerator; the intake branch pipe and the exhaust branch pipe are equipped with air exchange valves.

[0006] Furthermore, the outlet temperature of the primary heat storage body is controlled between 250°C and 500°C.

[0007] Furthermore, the SCR device loaded with the denitrification catalyst has at least one stage and at most three stages.

[0008] Furthermore, the denitrification catalyst is one or a combination of several of the following: vanadium-titanium catalyst, non-vanadium-based metal oxide catalyst, copper-based or iron-based molecular sieve.

[0009] Furthermore, a total exhaust gas flow meter is installed on the main intake pipe after the exhaust gas valve and before the induced draft fan; a branch exhaust gas flow meter is installed on the intake branch pipe of each heat storage chamber before the reversing valve.

[0010] Furthermore, an inlet NO is installed between the exhaust gas source and the exhaust valve of the intake manifold. X Concentration sensor; a branch pipe outlet NO is provided on the exhaust branch pipe of each regenerator after the reversing valve and before connecting to the main exhaust pipe. X Concentration sensor.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: (1) This utility model integrates denitrification VOC into an integrated RTO device, eliminating the need to add a denitrification device after the RTO, thus saving floor space and construction costs; (2) An SCR device independently supporting the denitrification catalyst is built, avoiding mutual wear between the catalyst and the heat storage brick, extending the overall life of the equipment, and allowing for separate disassembly and replacement of the catalyst without disassembling the heat storage body, reducing maintenance time; (3) The low-NOx burner reduces NO during combustion from the source. X The two-stage SCR catalyst generates (initial concentration reduced by 30%~40%), targeting the remaining NO. X Deep purification forms a "source reduction + end-of-pipe treatment" approach, which increases the total amount of pollutants removed compared to a single end-of-pipe treatment solution; at the same time; (4) low-NOx burners reduce NO X After concentration, the catalyst load of the SCR module is reduced, and the airflow stability is improved, which slows down the catalyst activity decay rate. At the same time, the amount of reducing agent sprayed is controlled according to the concentration and flow rate of the exhaust gas, which effectively reduces the ammonia escape rate and avoids secondary pollution. (5) Flow meters are installed on the main intake pipe and branch pipe, and concentration sensors are installed on the main intake pipe and exhaust pipe to ensure that the gas flow in the device is stable and controllable, which is beneficial to the gas and SCR device to fully contact each other and complete the denitrification, while reducing the risk of combustion chamber explosion. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0013] Labeling Explanation: 1-Low NOx burner, 2-Combustion chamber, 3-Regenerator chamber, 31-Primary regenerator, 32-Secondary regenerator, 33-Reducing agent spray port, 34-Primary SCR unit, 35-Secondary SCR unit, 4-Induced draft fan, 41-Main intake pipe, 42-Intake branch pipe, 43-Exhaust branch pipe, 44-Main exhaust pipe, 5-Purge fan, 51-Main purge pipe, 52-Purge valve, 53-Purge branch pipe exhaust valve, 6-Reversing valve, 7-Chimney. Detailed Implementation

[0014] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0015] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0016] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0017] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0018] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments. Example

[0020] An integrated denitrification VOC device includes a combustion chamber and three regenerator chambers connected to the combustion chamber. The combustion chamber is located above the regenerator chambers. Each regenerator chamber has an intake branch pipe, an exhaust branch pipe, and a purge branch pipe at its bottom. The intake port of each intake branch pipe is connected to the waste gas to be treated and an induced draft fan via a main intake pipe. The main intake pipe is equipped with an exhaust gas valve and a main intake valve. Each exhaust branch pipe is connected to a chimney via a main exhaust pipe, and each purge branch pipe is connected to a purge fan via a main purge pipe. The purge branch pipes are equipped with purge valves. A low-NOx burner is installed at the top of the combustion chamber. Each regenerator chamber, from the upper part near the combustion chamber to the lower part, is sequentially equipped with a primary regenerator, a reducing agent spray port, an SCR device loaded with a denitrification catalyst, and a secondary regenerator. The intake branch pipe and the exhaust branch pipe are equipped with air exchange valves.

[0021] Furthermore, the outlet temperature of the primary heat storage body is controlled between 250℃ and 350℃.

[0022] Furthermore, the SCR unit loaded with the denitrification catalyst has two stages.

[0023] Furthermore, the first-stage SCR unit is loaded with a vanadium-titanium catalyst with a high activity temperature, while the second-stage SCR unit is loaded with a non-vanadium-based metal oxide catalyst with a low activity temperature.

[0024] Furthermore, a total exhaust gas flow meter is installed on the main intake pipe after the exhaust gas valve and before the induced draft fan; a branch exhaust gas flow meter is installed on the intake branch pipe of each heat storage chamber before the reversing valve.

[0025] Furthermore, an inlet NO is installed between the exhaust gas source and the exhaust valve of the intake manifold. X Concentration sensor; a branch pipe outlet NO is provided on the exhaust branch pipe of each regenerator after the reversing valve and before connecting to the main exhaust pipe. X Concentration sensor.

[0026] The specific process of purifying waste gas in this utility model is as follows:

[0027] Nitrogen-containing organic waste gas and air are mixed in the intake pipe 41 to obtain mixed waste gas, and the mixed waste gas is sent into any one of the heat storage chambers 3 by the induced draft fan 4. The secondary heat storage body 32 and the primary heat storage body 31 in the heat storage chamber 3 heat the mixed waste gas step by step. At this time, the heat storage chamber 2 is in the heat release condition.

[0028] The heated mixed exhaust gas enters combustion chamber 2, where the temperature of the low-NOx burner 1 is controlled at 800℃~1000℃, ensuring that the VOCs in the mixed exhaust gas are fully oxidized into CO2 and H2O, while simultaneously producing a small amount of NO. X After the VOCs in the mixed waste gas are completely oxidized, they are discharged through the exhaust branch pipe 43 of another heat storage chamber 3. During the discharge process, the high-temperature mixed waste gas passes through the primary heat storage body 31 and the secondary heat storage body 32 in sequence to recover heat and store it. The temperature of the waste gas after passing through the primary heat storage body 31 is 250℃~500℃, and the temperature at the bottom of the heat storage chamber 3 is not greater than 100℃. Among them, after the high-temperature mixed waste gas that has completed VOCs purification passes through the primary heat storage body 31, it is mixed with the reducing agent sprayed from the reducing agent spray port 33. The mixed gas then passes through the primary SCR module 34, NO X The redox reaction (i.e., denitrification) continues with the aid of a catalyst. At this point, NO... X The removal rate reaches over 96%; after passing through the secondary SCR module for 35 minutes, the mixed waste gas undergoes further denitrification reaction, completing deep purification, reducing ammonia escape rate, and avoiding secondary pollution.

[0029] After the device completes one exhaust gas reversal, the heat storage chamber 3, which was in an exothermic state before the reversal, enters the gas purging stage. At this time, purging air is introduced through the purging branch pipe 52 of the heat storage chamber 3, which was in an exothermic state before the reversal, to blow the unreacted exhaust gas at its bottom into the combustion chamber 2, preventing the residual unreacted exhaust gas from being directly discharged from the exhaust branch pipe 43 when the heat storage chamber 3 enters the heat storage state after the next exhaust gas reversal, resulting in substandard exhaust gas. The reversing valve 6 and purging valve 51 of each heat storage chamber 3 are switched in sequence to control each heat storage chamber 3 to enter the exothermic, purging, and heat storage conditions in sequence, thus completing the continuous purification of exhaust gas.

[0030] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A denitrification VOC integrated device, comprising a combustion chamber (2) and multiple heat storage chambers (3) connected to the combustion chamber (2); the combustion chamber (2) is located at the upper part of the heat storage chamber (3); each heat storage chamber (3) has an inlet branch pipe (42), an exhaust branch pipe (43) and a purge branch pipe (53) at its bottom; the inlet of each inlet branch pipe (42) is connected to the waste gas to be treated and the induced draft fan (4) through the main inlet pipe (41), and the main inlet pipe (41) is provided with a waste gas valve and a main inlet valve; each exhaust branch pipe (43) is connected to the chimney (7) through the main exhaust pipe (44), and each purge branch pipe (53) is connected to the purge fan (5) through the main purge pipe (51); the purge branch pipe (53) is provided with a purge valve (52), characterized in that: The combustion chamber (2) is equipped with a low-NOx burner (1) at the top; each heat storage chamber (3) is equipped with a primary heat storage body (31), a reducing agent spray port (33), an SCR device (34) loaded with denitrification catalyst, and a secondary heat storage body (32) from the upper part to the lower part near the combustion chamber (2); the intake branch pipe (42) and the exhaust branch pipe (43) are equipped with a reversing valve (6).

2. The integrated VOC denitrification device as described in claim 1, characterized in that: The outlet temperature of the primary heat storage body (31) is controlled at 250℃~500℃.

3. The integrated VOC denitrification device as described in claim 1, characterized in that: The SCR unit (34) loaded with denitrification catalyst has at least one stage and at most three stages.

4. The integrated VOC denitrification device as described in claim 1, characterized in that: A total exhaust gas flow meter is provided on the main intake pipe (41) after the exhaust gas valve and before the induced draft fan (4); a branch exhaust gas flow meter is provided on the intake branch pipe (42) of each heat storage chamber (3) before the reversing valve (6).

5. The integrated VOC denitrification device as described in claim 1, characterized in that: An inlet NO is provided between the exhaust gas source and the exhaust valve of the intake manifold (41). X Concentration sensor; a branch pipe outlet NO is provided on the exhaust branch pipe (43) of each heat storage chamber (3) after the reversing valve (6) and before the exhaust main pipe (44). X Concentration sensor.

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