An organic waste gas pretreatment device based on a regenerative oxidation incinerator and a method of use

Abstract

The invention discloses an organic waste gas pretreatment device based on a regenerative oxidation incinerator and a method for using the device, and belongs to the technical field of waste gas treatment. It includes a VOCs waste gas intake pipe and an air intake pipe, which are connected to a mixing bellows a, a mixing bellows b, a heat exchanger a, a regenerative oxidation incinerator, a heat exchanger b, and a chimney in sequence through pipes after the intersection of the VOCs waste gas intake pipe and the air intake pipe; the device also includes a VOCs waste gas intake pipe generated by a production device, and the VOCs waste gas intake pipe generated by the production device is connected to a gas-liquid separator, and the gas-liquid separator is connected to a pipe connected between a mixing bellows a and a mixing bellows b through a pipe; two fans are arranged in parallel between the mixing bellows b and the heat exchanger a; and two combustion-supporting fans are arranged in parallel on the top of the regenerative oxidation incinerator. It solves a series of problems such as the process waste gas is prone to condensation, which leads to fire in the pipe, fan pollution, valve blockage, and heat storage body blockage.

Description

Technical Field

[0001] The invention relates to an organic waste gas pretreatment device based on a regenerative thermal oxidation incinerator (RTO) and a use method thereof, belonging to the technical field of waste gas treatment. Background Art

[0002] The process of thermal oxidation technology in the existing industrial organic waste gas treatment is that the fan sends the waste gas from the production equipment into the thermal oxidation device. After the waste gas is fully reacted in the oxidation device and undergoes sufficient heat exchange, it is discharged to the chimney.

[0003] For the VOCs waste gas intake conditions in the presence of ethylene glycol devices, under the conditions of high temperature, open flames, static electricity and a certain oxygen content, the previous process treatment process is very prone to dangerous fires in the pipe. At the same time, under the conventional process flow, after the ethylene glycol VOCs waste gas is condensed and polymerized, it is also easy to cause valve blockage, scaling on the surface of the RTO ceramic heat storage body, and RTO operating load reduction. For conventional fixed-frequency fans, unclean air is in direct contact with the fan, polluting the fan and easily causing an imbalance in the system's wind balance. Ethylene glycol VOCs waste gas is a toxic substance, and the risk of leakage increases when the fan is in an unstable state. Summary of the invention

[0004] The present invention provides an organic waste gas pretreatment device based on a regenerative thermal oxidation incinerator (RTO) and a method of use. A pre-pretreatment device, including a gas-liquid separator, a heat exchanger, an RTO and a waste gas treatment system in front of a variable frequency fan, belongs to the field of waste gas treatment technology. In particular, it is an organic waste gas treatment system for solving a series of problems such as VOCs gas at the rear end of the ethylene glycol device treatment, and process waste gas is prone to condensation, thereby causing fire in the pipeline, fan pollution, valve blockage, heat storage body blockage, etc.

[0005] A device for pretreating organic waste gas based on a regenerative thermal oxidation incinerator comprises a VOCs waste gas intake pipe and an air intake pipe, which are connected to a mixing wind box a, a mixing wind box b, a heat exchanger a, a regenerative thermal oxidation incinerator, a heat exchanger b and a chimney in sequence through pipes after the VOCs waste gas intake pipe and the air intake pipe intersect; the device also comprises a VOCs waste gas intake pipe generated by a production device, the VOCs waste gas intake pipe generated by the production device is connected to a gas-liquid separator, and the gas-liquid separator is connected to a pipeline connected between the mixing wind box a and the mixing wind box b through a pipeline; two fans are arranged in parallel between the mixing wind box b and the heat exchanger a; and two combustion-supporting fans are arranged in parallel on the top of the regenerative thermal oxidation incinerator.

[0006] The VOCs waste gas generated by the production device is the VOCs gas at the back end of the ethylene glycol device processing.

[0007] Furthermore, in the above technical solution, the gas-liquid separator is provided with a waste liquid outlet.

[0008] Furthermore, in the above technical solution, valves are provided on the pipelines connecting the blower and the combustion-supporting blower. When one blower or the combustion-supporting blower stops working, the other blower or the combustion-supporting blower starts working. The valve is a fully metal sealed valve.

[0009] Furthermore, in the above technical solution, the heat exchanger a and the heat exchanger b are both plate heat exchangers.

[0010] Furthermore, in the above technical solution, the fan is a variable frequency fan.

[0011] Furthermore, in the above technical solution, a burner is provided inside the regenerative thermal oxidation incinerator.

[0012] Furthermore, in the above technical solution, after the VOCs waste gas generated by the production enters the gas-liquid separator through the VOCs waste gas inlet pipe generated by the production device, the gas enters the mixing bellows b through the pipe, and the liquid is recovered through the waste liquid outlet.

[0013] The present invention also provides a method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator, comprising the following steps:

[0014] 1) Start a fan and a combustion-supporting fan, preheat the heat exchanger a to 60-70°C, preheat the heat exchanger b to 110-140°C, start the burner in the regenerative thermal oxidation incinerator, and make the temperature in the regenerative thermal oxidation incinerator 70-80°C;

[0015] 2) After the VOCs waste gas and air enter the pipeline, they are evenly mixed in the mixing wind box a and enter the mixing wind box b;

[0016] 3) The VOCs waste gas generated by the production device enters the pipeline and then enters the gas-liquid separator. The gas enters the mixing bellows b through the pipeline and is evenly mixed with the VOCs waste gas and air. The liquid flowing out of the gas-liquid separator is recovered through the waste liquid outlet;

[0017] 4) The mixed waste gas enters the heat exchanger a, and after the waste gas is heated to 60-70°C, it enters the regenerative oxidation incinerator, where the organic matter in the waste gas undergoes oxidation reaction to obtain clean gas;

[0018] 5) The clean gas enters the heat exchanger b, where the temperature is reduced to 110-140°C and is finally discharged through the chimney.

[0019] Furthermore, in the above technical scheme, the gas flow rate of the mixed gas when entering the mixing bellows a is 50000-100000NM3 / H, preferably 66341NM3 / H, the gas temperature is 15-55°C, and the pressure is 5-10KPA; the gas flow rate of the mixed gas when entering the regenerative thermal oxidation incinerator is 60000-120000NM3 / H, preferably 84186NM3 / H, the gas temperature is 70-80°C, preferably 74°C, and the pressure is 5-10KPA, preferably 5KPA.

[0020] Furthermore, in the above technical solution, the flow rate of the clean gas entering the heat exchanger b is 60000-120000 NM3 / H, preferably 84186 NM3 / H, the gas temperature is 130-150°C, preferably 110-140°C, and the pressure is 1.0-2.0 KPA, preferably 1.2-1.7 KPA.

[0021] Furthermore, in the above technical solution, the gas flow rate discharged from the chimney is 60000-120000NM3 / H, and the pressure is 1.0-2.0KPA.

[0022] The gas treated by the device and method of the present invention meets the emission standards and fully complies with the latest national laws and local standards of China.

[0023] The determined organic waste gas is treated according to the technical design data. This includes heating, oxidation, cooling of exhaust air / pure air and ducting. All other unreasonable utilizations are explicitly excluded. The system is designed to reduce the emission of organic waste gas, which is considered to be the maximum satisfaction of the emission standards required to be achieved according to the design level.

[0024] The Regenerative Thermal Oxidation (RTO) furnace uses the heat contained in the exhaust gas to carry out the combustion process. The heat generated during the combustion is stored in the ceramic thermal storage system and used for the second stage of the exhaust gas preheating process.

[0025] The operation mode of the whole process includes the following steps:

[0026] (Heating mode) The exhaust gas is preheated by the regenerator to a temperature close to that of the combustion chamber. The indicator light indicates the ignition point of the preheated gas in the combustion chamber.

[0027] The fully mixed exhaust gas is fully burned in the combustion chamber of the regenerative oxidation combustion furnace.

[0028] (Cooling stage) Clean air is introduced through the air blower and then enters and heats the thermal storage system, allowing the thermal storage system to heat the exhaust gas in the second stage.

[0029] When the clean air leaves the RTO unit, the outlet temperature is slightly higher than the exhaust gas inlet temperature, and the temperature difference depends on the efficiency of the heat exchanger in the unit.

[0030] · RTO's Pyro block linings and their ceramic filling materials allow to withstand combustion temperatures up to 1200°C, thus ensuring complete oxidation of organic pollutants.

[0031] The specially developed all-metal sealing valve of the purification system ensures that no unpurified exhaust gas will leak into the treated clean air.

[0032] The fan is frequency-controlled to adapt to the production fluctuations of the entire production line.

[0033] Advantageous Effects of the Invention

[0034] First, the entire exhaust gas treatment system operates safely and stably.

[0035] ① Through indirect heat exchange; cyclic self-cleaning removes the deposits formed on the heat exchanger and pipelines; the saddle ring filter intercepts most of the solid particles to prevent pipeline contamination. The fan is selected with variable frequency, one is on and the other is on standby according to the actual working conditions, and is used in a reasonable combination;

[0036] ②The fan is placed at the front end of the RTO to form a negative pressure state in the front end system. VOCs exhaust gas is a toxic substance and needs to be controlled and tested. The fan is placed in front to avoid insufficient upstream pressure, and the variable frequency motor avoids negative vacuum phenomenon to avoid leakage risks.

[0037] Second, the system is energy-efficient.

[0038] ① The overall energy consumption is reduced by means of heat exchangers, and the natural gas consumption is low; the RTO system has a high thermal efficiency of up to 97%, which can save energy. Through the plate heat exchanger, the temperature of the clean gas after incineration at the RTO outlet is recycled to the cold inlet for re-pretreatment and incineration.

[0039] ②The system has low wind resistance, which greatly reduces the operating power of the fan and reduces power consumption;

[0040] ③DCS can monitor the entire process, with fewer manual maintenance points, automated maintenance methods and low maintenance costs.

[0041] Third, it is easy to maintain.

[0042] The pretreatment device is easy to maintain. After the device is shut down, it can be repaired quickly and put into production quickly.

[0043] Fourth, the equipment’s treatment efficiency is in accordance with European standards and can reach up to 99.9%. It is implemented in accordance with the most stringent domestic standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is an organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator described in the present invention.

[0045] In the figure, 1. VOCs waste gas inlet duct; 2. Air inlet duct; 3. VOCs waste gas inlet duct generated by the production device; 4. Mixing bellows a; 5. Mixing bellows b; 6. Gas-liquid separator; 7. Waste liquid outlet; 8. Heat exchanger a; 9. Fan a; 10. Fan b; 11. Valve a; 12. Valve b; 13. Regenerative oxidation incinerator; 14. Combustion-supporting fan a; 15. Combustion-supporting fan b; 16. Valve c; 17. Valve d; 18. Heat exchanger b; 19. Chimney; 20. Burner. DETAILED DESCRIPTION

[0046] The following non-limiting embodiments may enable a person skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0047] Example 1

[0048] like Figure 1 As shown, an organic waste gas pretreatment device based on a regenerative oxidation incinerator comprises a VOCs waste gas intake pipe 1 and an air intake pipe 2, which are connected to a mixing wind box a 4, a mixing wind box b 5, a heat exchanger a 8, a regenerative oxidation incinerator 13, a heat exchanger b18, and a chimney 19 in sequence through pipes after the VOCs waste gas intake pipe 1 and the air intake pipe 2 intersect; the device also comprises a VOCs waste gas intake pipe 3 generated by a production device, the VOCs waste gas intake pipe 3 generated by the production device is connected to a gas-liquid separator 6, and the gas-liquid separator 6 is connected to a pipe connected between the mixing wind box a 4 and the mixing wind box b 5 through a pipe; two fans are arranged in parallel between the mixing wind box b 5 and the heat exchanger a 8; two combustion-supporting fans are arranged in parallel on the top of the regenerative oxidation incinerator 13, and a burner 20 is arranged inside the regenerative oxidation incinerator 13. A waste liquid outlet 7 is arranged on the gas-liquid separator 6. The pipes connecting the blower and the combustion-supporting blower are provided with valves. When one blower or the combustion-supporting blower stops working, the other blower or the combustion-supporting blower starts working; the valve is a full metal sealing valve. The heat exchanger a 8 and the heat exchanger b 18 are both plate heat exchangers. The blower is a variable frequency blower. After the VOCs waste gas generated by the production enters the gas-liquid separator 6 through the VOCs waste gas inlet pipe 3 generated by the production device, the gas enters the mixing wind box b 5 through the pipe, and the liquid is recovered through the waste liquid outlet 7.

[0049] Example 2

[0050] A method for using an organic waste gas pretreatment device based on a regenerative oxidation incinerator comprises the following steps:

[0051] 1) Start a fan and a combustion-supporting fan, preheat the heat exchanger a to 60-70°C, and preheat the heat exchanger b to 110-140°C;

[0052] 2) After the VOCs waste gas and air enter the pipeline, they are evenly mixed in the mixing wind box a and enter the mixing wind box b;

[0053] 3) The VOCs waste gas generated by the production device enters the pipeline and then enters the gas-liquid separator. The gas enters the mixing bellows b through the pipeline and is evenly mixed with the VOCs waste gas and air. The liquid flowing out of the gas-liquid separator is recovered through the waste liquid outlet;

[0054] 4) After mixing (flow rate: 50000-100000NM3 / H, temperature: winter 15-25℃ / summer 45-55℃, pressure: 5-10KPA), the waste gas enters the heat exchanger a, and the waste gas is heated to 60-70℃ and then enters the regenerative thermal oxidation incinerator (the waste gas flow rate entering the regenerative thermal oxidation incinerator: 60000-120000NM3 / H temperature: 70-80℃, pressure: 5-10KPA), and the organic matter in the waste gas undergoes oxidation reaction to obtain clean gas (flow rate: 60000-120000 NM3 / H, temperature: 130-150℃, pressure: 1.0-2.0KPA);

[0055] 5) The clean gas enters the heat exchanger b, where the temperature is reduced to 110-140°C, and is finally discharged through the chimney (flow rate: 60000-120000NM3 / H, temperature: 110-140°C, pressure: 1.0-2.0KPA).

[0056] Table 1 Configuration parameters of regenerative thermal oxidation incinerator

[0057] Classification Specifications Remark form Two-box <![CDATA[Maximum processing capacity (Nm 3 / h)]]> 90,000 Operational flexibility 25％～120％ <![CDATA[Maximum intake air volume (Nm 3 / h)]]> ～42,000 Air volume depends on actual working conditions Inlet air temperature (℃) 30 RTO system thermal efficiency (%) 97 High heat exchange efficiency can save energy <![CDATA[Treatment effect (mg / Nm 3 )]]> <20 Average measured concentration RTO internal maximum temperature resistance (℃) 1200 Outlet temperature(℃) Approx. 70 Valve leakage rate <0.05％ Design service life >20 years size approx.10x 6x 8m

[0058] The RTO regenerative waste gas incinerator of the present invention meets environmental protection requirements after waste gas is incinerated.

[0059] Emission compliance This set of purification equipment will fully comply with China's latest national regulations and standards - "Comprehensive Emission Standards for Air Pollutants" GB 16297-1996 and Dalian's latest local standards. And follow the GB31571-2015 petrochemical industry pollutant emission standards, based on the project emission standards and the most stringent emission standards.

Claims

1. A method for using an organic waste gas pretreatment device based on a regenerative oxidation incinerator, characterized in that: The device comprises a VOCs waste gas intake pipe (1) and an air intake pipe (2), wherein the VOCs waste gas intake pipe (1) and the air intake pipe (2) are connected to a mixing wind box a (4), a mixing wind box b (5), a heat exchanger a (8), a regenerative thermal oxidation incinerator (13), a heat exchanger b (18), and a chimney (19) in sequence through pipes after the VOCs waste gas intake pipe (1) and the air intake pipe (2) intersect; the device also comprises a VOCs waste gas intake pipe (3) generated by a production device, wherein the VOCs waste gas intake pipe (3) generated by the production device is connected to a gas-liquid separator (6), and the gas-liquid separator (6) is connected to a pipe connecting the mixing wind box a (4) and the mixing wind box b (5) through a pipe; two fans are arranged in parallel between the mixing wind box b (5) and the heat exchanger a (8); and two combustion-supporting fans are arranged in parallel on the top of the regenerative thermal oxidation incinerator (13); The VOCs waste gas generated by the production device is the VOCs gas at the back end of the ethylene glycol device treatment; The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator comprises the following steps: 1) Start a fan and a combustion-supporting fan, preheat the heat exchanger a to 60-70°C, preheat the heat exchanger b to 110-140°C, start the burner in the regenerative thermal oxidation incinerator, and make the temperature in the regenerative thermal oxidation incinerator 70-80°C; 2) After the VOCs exhaust gas and air enter the pipeline, they are evenly mixed in the mixing bellows a and then enter the mixing bellows b; 3) The VOCs waste gas generated by the production device enters the pipeline and then enters the gas-liquid separator. The gas enters the mixing bellows b through the pipeline and is evenly mixed with the VOCs waste gas and air. The liquid flowing out of the gas-liquid separator is recovered through the waste liquid outlet; 4) The mixed exhaust gas enters the heat exchanger a, and after the exhaust gas is heated to 60-70℃, it enters the regenerative oxidation incinerator, where the organic matter in the exhaust gas undergoes oxidation reaction to obtain clean gas; 5) The clean gas enters the heat exchanger b, where the temperature is reduced to 110-140°C and is finally discharged through the chimney.

2. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: The gas-liquid separator (6) is provided with a waste liquid outlet (7).

3. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: Valves are provided on the pipelines connecting the blower and the combustion-supporting blower. When one blower or the combustion-supporting blower stops working, the other blower or the combustion-supporting blower starts working. The valves are all-metal sealing valves.

4. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: The heat exchanger a (8) and the heat exchanger b (18) are both plate heat exchangers.

5. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: The fan is a variable frequency fan; a burner (20) is provided inside the regenerative thermal oxidation incinerator (13).

6. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: After the VOCs waste gas generated in the production enters the gas-liquid separator (6) through the VOCs waste gas inlet pipe (3) generated by the production device, the gas enters the mixing wind box b (5) through the pipe, and the liquid is recovered through the waste liquid outlet (7).

7. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: The gas flow rate when the mixed gas enters the mixing bellows a is 50000-100000Nm 3 / h, gas temperature is 15-55℃, pressure is 5-10kPa; gas flow rate when mixed gas enters the regenerative thermal oxidation incinerator is 60000-120000Nm 3 / h, the gas temperature is 70-80℃ and the pressure is 5-10kPa.

8. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: The flow rate of clean gas entering heat exchanger b is 60000-120000 Nm 3 / h, gas temperature: 130-150 ℃, pressure: 1.0-2.0kPa.

9. The method for using the organic waste gas pretreatment device based on the regenerative thermal oxidation incinerator according to claim 1 is characterized in that: The gas flow rate out of the chimney is 60000-120000 Nm 3 / h, pressure is 1.0-2.0kPa.

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