Thermal storage oxidizer for treating low concentration volatile organic compound exhaust gas

Abstract

The present invention provides a thermal storage oxidation device for treating low-concentration volatile organic compound emission gas, wherein the furnace wall is connected to the first thermal storage chamber and the second thermal storage chamber to form a combustion chamber; an auxiliary burner is installed in the combustion chamber; the other ends of the first thermal storage chamber and the second thermal storage chamber are respectively connected to the reversing valve through air flow pipelines; the reversing valve is also connected to the VOCs air intake pipeline and the flue gas emission pipeline; the flue gas emission pipeline branches out a flue gas circulation branch; the flue gas circulation branch is connected to the air flow pipeline through a fan. By adjusting the steering valve, the gas flow direction in the device changes alternately, realizing the alternating absorption and release of heat between the two thermal storage chambers. The present invention minimizes the heat loss carried away by the flue gas through external flue gas recirculation, and maintains the temperature in the combustion chamber above the VOCs oxidation temperature level without or with less auxiliary fuel, thereby ensuring the high-temperature oxidation of VOCs and achieving the purpose of continuous and stable removal of low-concentration VOCs waste gas.

Description

Technical Field

[0001] The invention belongs to the technical field of energy environment devices, and in particular relates to a thermal storage oxidation device for treating low-concentration volatile organic compound emission gas. Background Art

[0002] Industrial production processes often produce a large amount of low-concentration volatile organic compounds (VOCs), such as medicine, petrochemicals, printing, electronics, and manufacturing. VOCs generally have a foul odor, damage the ozone layer, cause haze weather, and produce photochemical smog. They are very harmful to human health and are listed as atmospheric pollutants that need to be focused on prevention and control. Thermal oxidation, also known as combustion, is a method of cracking and completely oxidizing organic matter in exhaust gas into substances such as carbon dioxide and water at a temperature higher than the ignition point of organic matter. It is suitable for environmentally sound treatment of different types of VOCs. Thermal storage oxidation technology preheats the organic waste gas through the heat storage body to reach the required oxidation temperature. However, when the VOCs concentration is low, it is difficult for the system to achieve its own thermal maintenance, and auxiliary fuel is required to maintain the required reaction temperature level, resulting in increased energy consumption and increased processing costs.

[0003] To this end, a thermal storage oxidation device for treating volatile organic compound exhaust gas was invented to address the above problems. This technology reduces the heat loss carried away by the exhaust gas by introducing flue gas circulation outside the furnace, and can achieve continuous operation of the low-concentration VOCs treatment device under the condition of using little or no auxiliary fuel. Compared with other technologies, it expands the range of low-concentration VOCs treated by the thermal storage oxidation device, and has the advantage of reducing system energy consumption and operating costs. Summary of the invention

[0004] The object of the present invention is to overcome the deficiencies of the prior art and provide a thermal storage oxidation device for treating low-concentration volatile organic compound exhaust gas.

[0005] In order to achieve the above object, the present invention provides a thermal storage oxidation device for treating low-concentration volatile organic compound exhaust gas.

[0006] A thermal storage oxidation device for treating low-concentration volatile organic compound emission gas comprises an upper and lower layer of furnace walls arranged in parallel, wherein the two sides of the furnace wall in the length direction are respectively connected to a first heat storage chamber and a second heat storage chamber to form a combustion chamber; the other end of the first heat storage chamber is connected to a reversing valve through a second air flow pipeline, and the other end of the second heat storage chamber is connected to the reversing valve through a first air flow pipeline; the reversing valve is also respectively connected to a first VOCs waste gas intake pipeline, a second VOCs waste gas intake pipeline, a first flue gas emission branch, and a second flue gas emission branch; the first flue gas emission branch is connected to a second flue gas circulation branch, and the second flue gas emission branch is connected to the first flue gas circulation branch; the second flue gas circulation branch is equipped with a second circulation fan, and the first flue gas circulation branch is equipped with a first circulation fan; the outlet of the second circulation fan is connected to the second air flow pipeline, and the outlet of the first circulation fan is connected to the first air flow pipeline.

[0007] Preferably, the present invention has an auxiliary burner installed on the upper furnace wall of the combustion chamber.

[0008] Preferably, the waste gas of the present invention enters the first air flow pipeline from the first VOCs waste gas intake pipeline through the reversing valve, and then enters the second heat storage chamber to absorb heat and raise the temperature to above the oxidation temperature of VOCs, and is fully oxidized in the combustion chamber. The flue gas after the reaction flows through the first heat storage chamber, transfers the heat to the heat storage chamber and then enters the second air flow pipeline, and then enters the first flue gas emission pipeline through the reversing valve; part of the flue gas is discharged to the external environment from the first flue gas emission pipeline, and part of the flue gas enters the first flue gas circulation branch, enters the first air flow pipeline after being pressurized by the first circulation fan, mixes with the VOCs waste gas entering from the first VOCs waste gas intake pipeline, and heats the VOCs waste gas.

[0009] Preferably, the waste gas of the present invention enters the second air flow pipeline through the second VOCs waste gas intake pipeline through the reversing valve, and then enters the first heat storage chamber to absorb heat and raise the temperature to above the oxidation temperature of VOCs, and is fully oxidized in the combustion chamber. The flue gas after the reaction flows through the second heat storage chamber, transfers the heat to the heat storage chamber and then enters the air flow pipeline, and then enters the second flue gas emission branch through the reversing valve; part of the flue gas is discharged to the external environment from the second flue gas emission branch, and part of the flue gas enters the second flue gas circulation branch, enters the second air flow pipeline after being pressurized by the second circulation fan, mixes with the VOCs waste gas entering from the second air flow pipeline, and heats the VOCs waste gas.

[0010] The combustion chamber of the present invention is connected to the first heat storage chamber and the second heat storage chamber on both sides, and the furnace wall is connected to the first heat storage chamber and the second heat storage chamber to form a combustion chamber; an auxiliary burner is installed in the combustion chamber; the other ends of the first heat storage chamber and the second heat storage chamber are connected to the reversing valve through the air flow pipeline; the reversing valve is also connected to the VOCs air intake pipeline and the smoke exhaust pipeline; the smoke exhaust pipeline branches out a smoke circulation branch; the smoke circulation branch is connected to the air flow pipeline through a fan. By adjusting the steering valve, the gas flow direction in the device changes alternately, realizing the alternating absorption and release of heat between the two heat storage chambers.

[0011] The present invention reduces the heat loss carried away by the flue gas to the greatest extent through external flue gas recirculation, maintains the temperature in the combustion chamber above the VOCs oxidation temperature level without or with little auxiliary fuel, ensures the high-temperature oxidation of VOCs, and realizes the continuous and stable removal of VOCs in the exhaust gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic structural diagram of the thermal storage oxidation device of the present invention. DETAILED DESCRIPTION

[0013] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally. Example

[0014] like Figure 1 As shown, the thermal storage oxidation device for treating low-concentration volatile organic compound exhaust gas of the present invention comprises two layers of furnace walls 2 arranged in parallel, the two sides of the furnace wall 2 in the length direction are respectively connected to the first regenerator 14 and the second regenerator 4 to form a combustion chamber 3; the other end of the first regenerator 14 is connected to the reversing valve 10 through the second air flow pipeline 13, and the other end of the second regenerator 4 is connected to the reversing valve 10 through the first air flow pipeline 5; the reversing valve 10 is also connected to the first VOCs exhaust gas intake pipeline 11 respectively. 1. A second VOCs waste gas intake pipeline 12, a first flue gas emission branch 7, and a second flue gas emission branch 8; the first flue gas emission branch 7 is connected to the second flue gas circulation branch 16, and the second flue gas emission branch 8 is connected to the first flue gas circulation branch 15; the second flue gas circulation branch 16 is equipped with a second circulation fan 9, and the first flue gas circulation branch 15 is equipped with a first circulation fan 6; the outlet of the second circulation fan 9 is connected to the second airflow pipeline 13, and the outlet of the first circulation fan 6 is connected to the first airflow pipeline 5.

[0015] like Figure 1As shown, an auxiliary burner 1 is installed on the upper furnace wall of the combustion chamber 3 of the present invention.

[0016] like Figure 1 As shown, the present invention achieves alternating heat absorption and release between the two heat storage chambers by adjusting the diverter valve 10 so that the gas flow direction in the device changes alternately. The first state is that the VOCs waste gas enters the first air flow pipeline 5 through the diverter valve 10 from the first VOCs waste gas intake pipeline 11, and then enters the second heat storage chamber 4 to absorb heat and heat up to above the oxidation temperature of VOCs, and is fully oxidized in the combustion chamber 3. The flue gas after the reaction flows through the first heat storage chamber 14, transfers the heat to the heat storage chamber, and then enters the second air flow pipeline 13, and then enters the first flue gas discharge pipeline 7 through the reversing valve 10; a part of the flue gas is discharged to the external environment from the first flue gas discharge pipeline 7, and a part of the flue gas enters the first flue gas circulation branch 15, and enters the first air flow pipeline 5 after being pressurized by the first circulation fan 6, and is mixed with the VOCs waste gas entering from the first VOCs waste gas intake pipeline 11, and the VOCs waste gas is heated. After a cycle, the diverter valve 10 is switched, and the system enters the second state.

[0017] The second state is that the VOCs waste gas enters the second air flow pipeline 13 through the second VOCs waste gas intake pipeline 12 through the reversing valve 10, and then enters the first heat storage chamber 14 to absorb heat and heat up to above the oxidation temperature of VOCs, and is fully oxidized in the combustion chamber 3. The flue gas after the reaction flows through the second heat storage chamber 4, transfers the heat to the heat storage chamber, and then enters the air flow pipeline 5, and then enters the second flue gas discharge branch 8 through the reversing valve 10; part of the flue gas is discharged to the external environment from the second flue gas discharge branch 8, and part of the flue gas enters the second flue gas circulation branch 16, and enters the second air flow pipeline 13 after being pressurized by the second circulation fan 9, and is mixed with the VOCs waste gas entering from the second air flow pipeline 13, and the VOCs waste gas is heated. In the next cycle, the system switches to the first operating state again, and the cycle repeats.

Claims

1. A thermal storage oxidation device for treating low-concentration volatile organic compound exhaust gas, characterized in that: The invention comprises two layers of furnace walls (2) arranged in parallel, the two sides of the furnace wall (2) in the length direction are respectively connected to a first heat storage chamber (14) and a second heat storage chamber (4), so as to enclose a combustion chamber (3); the other end of the first heat storage chamber (14) is connected to a reversing valve (10) through a second air flow pipeline (13), and the other end of the second heat storage chamber (4) is connected to the reversing valve (10) through a first air flow pipeline (5); the reversing valve (10) is also respectively connected to a first VOCs waste gas intake pipeline (11) and a second VOCs waste gas intake pipeline (12) , a first smoke exhaust branch (7), and a second smoke exhaust branch (8); the first smoke exhaust branch (7) is connected to the second smoke circulation branch (16), and the second smoke exhaust branch (8) is connected to the first smoke circulation branch (15); the second smoke circulation branch (16) is equipped with a second circulation fan (9), and the first smoke circulation branch (15) is equipped with a first circulation fan (6); the outlet of the second circulation fan (9) is connected to the second airflow pipeline (13), and the outlet of the first circulation fan (6) is connected to the first airflow pipeline (5); An auxiliary burner (1) is installed on the upper furnace wall of the combustion chamber (3); The waste gas enters the first air flow pipeline (5) through the first VOCs waste gas intake pipeline (11) through the reversing valve (10), and then enters the second heat storage chamber (4) to absorb heat and raise the temperature to above the oxidation temperature of VOCs, and is fully oxidized in the combustion chamber (3). The flue gas after the reaction flows through the first heat storage chamber (14), transfers the heat to the heat storage chamber, and then enters the second air flow pipeline (13), and then enters the first flue gas discharge pipeline (7) through the reversing valve (10); a part of the flue gas is discharged to the external environment through the first flue gas discharge pipeline (7), and a part of the flue gas enters the first flue gas circulation branch (15), and enters the first air flow pipeline (5) after being pressurized by the first circulation fan (6), and is mixed with the VOCs waste gas entering from the first VOCs waste gas intake pipeline (11), and the VOCs waste gas is heated; The waste gas enters the second air flow pipeline (13) through the second VOCs waste gas intake pipeline (12) through the reversing valve (10), and then enters the first heat storage chamber (14) to absorb heat and heat up to above the oxidation temperature of VOCs, and is fully oxidized in the combustion chamber (3). The flue gas after the reaction flows through the second heat storage chamber (4), transfers heat to the heat storage chamber, and then enters the air flow pipeline (5), and then enters the second flue gas emission branch (8) through the reversing valve (10); a part of the flue gas is discharged to the external environment through the second flue gas emission branch (8), and a part of the flue gas enters the second flue gas circulation branch (16), is pressurized by the second circulation fan (9), enters the second air flow pipeline (13), mixes with the VOCs waste gas entering from the second air flow pipeline (13), and heats the VOCs waste gas.

Images