A heat-collecting RTO treatment system suitable for high-concentration VOCs waste gas

Abstract

The present invention discloses a heat-collecting RTO treatment system suitable for high-concentration VOCs waste gas, which includes an RTO system, a combustion chamber is provided in the RTO system, a plurality of functional chambers arranged in sequence are provided below the combustion chamber, an air intake pipe of high-concentration VOCs waste gas is connected to an induced draft system through a valve, the induced draft system is connected to the functional chamber, the bottom of the functional chamber is connected to a chimney, the middle of each functional chamber in the RTO system is connected in parallel to a waste heat boiler system through a valve, and the waste heat boiler system is connected to the combustion chamber through a valve to form a loop. After being treated by this system, the exhaust gas temperature is consistent with the normal RTO exhaust gas temperature of 60°C, which effectively solves the problem of overheating at the top of the RTO for treating waste gas containing high-concentration VOCs on the one hand; on the other hand, the heat storage body inside the RTO is divided into a high-temperature part and a low-temperature part, and the structure of this system realizes the functional replacement of the waste heat boiler for the high-temperature part of the heat storage body, thereby greatly improving the comprehensive heat treatment capacity of the system.

Description

Technical Field

[0001] The invention relates to a heat collecting RTO treatment system suitable for high-concentration VOCs waste gas, belonging to the technical field of waste gas treatment equipment. Background Art

[0002] Volatile organic compounds (VOCs) are an important component of air pollutants, and they are mainly derived from processes such as petrochemicals, pharmaceutical production, paint decoration, transportation, and garbage storage. VOCs, together with sulfates and nitrates generated by SO2, NOX, etc., will generate haze mainly composed of PM2.5 fine particles under the action of light, which has a serious impact on human health. At present, the main VOCs treatment processes include absorption method, direct adsorption method, adsorption + combustion method, low-temperature plasma method, biological method, etc. Among them, the most widely used is adsorption + combustion method, which mainly includes catalytic combustion (CO), regenerative thermal combustion (RTO) and regenerative catalytic combustion (RCO) and other technologies.

[0003] At present, the thermal efficiency of most RTO bodies reaches more than 95%. For the exhaust gas entering the RTO system at room temperature, the exhaust temperature is about 60°C. For RTOs that treat high-concentration exhaust gas, due to economic factors such as investment budget and space layout, the system often has problems with overheating, which affects the safety and life of the equipment. In order to avoid the occurrence of this problem, it is usually practiced to install a thermal bypass on the top of the RTO and maintain a certain opening. The gas discharged through the thermal bypass is clean gas, but its exhaust temperature is as high as 850°C or more and must be treated to meet the safety emission standards. In addition, if this high-grade heat source cannot be effectively utilized, the overall energy efficiency of the system will be greatly reduced. In response to the above situation, there are currently two main treatment methods:

[0004] 1. Install a heat exchanger between the RTO top and the chimney after the heat bypass (heat exchange efficiency is about 60%-70%), and the exhaust gas temperature after treatment is 200-300℃;

[0005] 2. Install a heat exchanger between the top of the RTO and the chimney after the heat bypass (heat exchange efficiency is about 70%-90%). The exhaust gas temperature after treatment is 200-300℃, and steam and hot water can be produced at the same time.

[0006] The exhaust gas temperature after treatment in the above manner meets the safety emission requirements, but there is still a large amount of medium-grade energy that cannot be effectively utilized. Summary of the invention

[0007] The technical problem to be solved by the present invention is that after the temperature of the existing treated exhaust gas meets the safety emission requirements, a large amount of medium-grade energy still cannot be effectively utilized.

[0008] In order to solve the above technical problems, the present invention provides a heat-collecting RTO treatment system suitable for high-concentration VOCs waste gas, including an RTO system, a combustion chamber is provided in the RTO system, an ignition device is provided on the top of the combustion chamber, and a plurality of functional chambers arranged in sequence are provided below the combustion chamber. The high-concentration VOCs waste gas inlet pipe is connected to the induced draft system through a valve, the induced draft system is connected to the bottom of each functional chamber through a valve, and the bottom of each functional chamber is connected to the chimney through a valve, characterized in that the middle of each functional chamber in the RTO system is connected in parallel with the waste heat boiler system through a valve, and the waste heat boiler system is connected to the combustion chamber through a valve to form a loop. The high-temperature flue gas discharged from the combustion chamber is used as a heat source for the waste heat boiler system for high-grade steam production, and the medium-grade exhaust gas after heat exchange is sent to the middle of the RTO system, and once again heat exchanged through the ceramic heat storage body, and finally discharged from the bottom of each functional chamber. The high-concentration VOCs waste gas is connected to the RTO system for thermal oxidation, and CO2 and water are produced after oxidation and decomposition, and the clean gas is discharged to the chimney through the waste gas outlet pipe.

[0009] Preferably, the high-concentration VOCs waste gas inlet pipe is also connected to the emergency bypass pipeline through a valve, and the air outlet of the emergency bypass pipeline is connected to the chimney; when the equipment is handling safe working conditions, the high-concentration VOCs waste gas in the high-concentration VOCs waste gas inlet pipe is directly introduced into the chimney.

[0010] Preferably, the functional chambers include a cleaning chamber, a heating chamber, and a cooling chamber in sequence.

[0011] Preferably, the air inlet of the air induced system is also connected to the fresh air system through a fresh air valve.

[0012] More preferably, after the heat-collecting RTO treatment system is started, the system is purged and heated by fresh air introduced by the fresh air system.

[0013] Preferably, the bottom of each functional chamber is connected to the air inlet of the air induced system via a valve.

[0014] Preferably, the high-concentration VOCs waste gas in the high-concentration VOCs waste gas inlet pipe is powered by a fan motor in the induced draft system, and the fan motor is controlled by a frequency converter.

[0015] The gas treated by the waste heat boiler system is not discharged directly into the chimney, but continues to enter the system from the middle of the RTO system, thereby achieving efficient use of energy.

[0016] The present invention provides an efficient heat-collecting RTO treatment system suitable for high-concentration VOCs waste gas. After being treated by the system, the exhaust gas temperature is consistent with the normal RTO exhaust temperature of 60°C. On the one hand, it effectively solves the problem of top overtemperature of the RTO for treating waste gas containing high-concentration VOCs; on the other hand, the heat storage body inside the RTO is divided into a high-temperature part and a low-temperature part. The structure of the system realizes the functional replacement of the high-temperature part of the heat storage body by the waste heat boiler, thereby greatly improving the comprehensive heat treatment capacity of the system; furthermore, high-quality heat sources are used for the waste heat boiler, which maximizes the thermal efficiency of the waste heat boiler, thereby also ensuring the quality of the output steam; most importantly, it fundamentally solves the production efficiency problems such as energy loss and increased pipeline material costs caused by conventional emissions, thereby realizing the maximum utilization of system energy.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Effectively solve the problem of overheating at the top of RTO for treating waste gas containing high concentration of VOCs;

[0019] 2. The heat storage body inside the RTO is divided into a high-temperature part and a low-temperature part. The structure of this system realizes the functional replacement of the high-temperature part of the heat storage body by the waste heat boiler, thereby greatly improving the comprehensive heat treatment capacity of the system;

[0020] 3. High-quality heat source is used for waste heat boiler, which maximizes the thermal efficiency of waste heat boiler and ensures the quality of output steam;

[0021] 4. It fundamentally solves the production efficiency problems such as energy loss and increased pipeline material costs caused by conventional emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the heat-collecting RTO treatment system provided by the present invention. DETAILED DESCRIPTION

[0023] In order to make the present invention more clearly understood, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0024] Example

[0025] like Figure 1 As shown, a heat-collecting RTO treatment system suitable for high-concentration VOCs waste gas provided by the present invention includes an RTO system 4, a combustion chamber is provided in the RTO system 4, an ignition device is provided on the top of the combustion chamber, and three functional chambers arranged in sequence are provided below the combustion chamber, namely a cleaning chamber, a heating chamber, and a cooling chamber.

[0026] The high-concentration VOCs waste gas inlet pipe 8 is connected to the induced draft system 3 and the emergency bypass pipeline 1 through valves e and m, respectively. The induced draft system 3 is connected to the bottom of the cleaning room, heating room, and cooling room through valves g, valve i, and valve k, respectively. The bottoms of the cleaning room, heating room, and cooling room are connected to the chimney 6 through valves h, valve j, and valve l, respectively. The bottoms of the cleaning room, heating room, and cooling room are also connected to the air inlet of the induced draft system 3 through valves n, valve o, and valve p, respectively. The pipeline between valve e and the induced draft system 3 is connected to the fresh air system 2 through the fresh air valve f. After the heat-collecting RTO treatment system is started, the system is purged and heated by the fresh air introduced by the fresh air system. The emergency bypass pipeline 1 is directly connected to the chimney 6. When the equipment is in a safe working condition, the high-concentration VOCs waste gas in the high-concentration VOCs waste gas inlet pipe 8 is directly introduced into the chimney 6.

[0027] The combustion chamber in the RTO system 4 is connected to the waste heat boiler system 5 through valve a, and the waste heat boiler system 5 is connected to the middle of the cleaning chamber, the heating chamber, and the cooling chamber through valves b, c, and d, respectively, so that a loop is formed between the waste heat boiler system 5 and the combustion chamber. The gas treated by the waste heat boiler system 5 is not directly discharged into the chimney 6, but continues to be introduced into the system from the middle of the RTO system 4, thereby realizing efficient use of energy.

[0028] The high-concentration VOCs waste gas in the high-concentration VOCs waste gas inlet pipe 8 is powered by the fan motor in the induced draft system 3, and the fan motor is controlled by a frequency converter.

[0029] The high-temperature flue gas discharged from the combustion chamber is used as the heat source of the waste heat boiler system 5 for high-grade steam production. After heat exchange, the medium-grade exhaust gas is sent to the middle of the RTO system 4, and once again passes through the ceramic heat storage body for heat exchange, and finally discharged from the bottom of each functional room. High-concentration VOCs waste gas is connected to the RTO system 4 for thermal oxidation, and after oxidation and decomposition, CO2 and water are produced, which become clean gas and are discharged to the chimney through the waste gas outlet pipe.

Claims

1. A heat collecting RTO treatment system suitable for high-concentration VOCs waste gas, comprising an RTO system (4), wherein a combustion chamber is provided in the RTO system (4), an ignition device (7) is provided on the top of the combustion chamber, and a plurality of sequentially arranged functional chambers are provided below the combustion chamber, an air intake pipe (8) for high-concentration VOCs waste gas is connected to an air intake system (3) through a valve, the air intake system (3) is connected to the bottom of each functional chamber through a valve, and the bottom of each functional chamber is connected to a chimney (6) through a valve, wherein: The middle of each functional chamber in the RTO system (4) is connected in parallel with the waste heat boiler system (5) through a valve, and the waste heat boiler system (5) is connected with the combustion chamber through a valve to form a loop; the functional chambers include a cleaning chamber, a heating chamber, and a cooling chamber in sequence, and the bottom of each functional chamber is connected to the air inlet of the induced draft system (3) through a valve.

2. The heat-collecting RTO treatment system for high-concentration VOCs waste gas according to claim 1, characterized in that: The high-concentration VOCs waste gas inlet pipe (8) is also connected to the emergency bypass pipeline (1) via a valve, and the outlet of the emergency bypass pipeline (1) is connected to the chimney (6); when the equipment is in a safe working condition, the high-concentration VOCs waste gas in the high-concentration VOCs waste gas inlet pipe (8) is directly introduced into the chimney (6).

3. The heat-collecting RTO treatment system for high-concentration VOCs waste gas according to claim 1, characterized in that: The air inlet of the air induced system (3) is also connected to the fresh air system (2) via a fresh air valve (f).

4. The heat-collecting RTO treatment system for high-concentration VOCs waste gas according to claim 3, characterized in that: After the heat-collecting RTO treatment system is started, the fresh air introduced by the fresh air system is used to blow and heat the system.

5. The heat-collecting RTO treatment system for high-concentration VOCs waste gas according to claim 1, characterized in that: The high-concentration VOCs waste gas in the high-concentration VOCs waste gas inlet pipe (8) is powered by a fan motor in the induced draft system (3), and the fan motor is controlled by a frequency converter.

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