CN107366922A - The humidity control system and its regulation technique of a kind of RTO oxidation furnaces - Google Patents

Abstract

The invention discloses the humidity control system of RTO oxidation furnaces, organic exhaust gas is entered RTO regenerator by the system by switch valve, after being heated by heat storage, into oxidation Indoor Combustion, high temperature purification gas after burning enters back into regenerator, heat storage body, after purified gas cooling, chimney is discharged to through air-introduced machine；When RTO oxidizing chambers overtemperature is more than more than 850 DEG C of RTO normal operating temperatures, starts circulation temperature lowering loop and carry out circulation tonifying Qi, ensure the normal operation of system.Draw Partial cleansing gas into oxidizing chamber or mixed with waste gas, purification gas flow is controlled by control valve after air-introduced machine.Draw Partial cleansing gas and enter oxidizing chamber, utilize the low temperature regulation oxidation room temperature of purification gas.Draw Partial cleansing gas to mix with waste gas, reduce VOCs content, regulation oxidation room temperature, ensure that the temperature normal work of whole RTO oxidation furnaces.

Description

A temperature adjustment system and its adjustment process of an RTO oxidation furnace

technical field

The invention relates to an RTO temperature regulating process, which is mainly suitable for VOCs treatment in painting, printing, shoemaking, chemical production, pharmaceutical and other industries, especially the RTO treatment process of high-concentration VOCs.

Background technique

In recent years, large-scale smog has occurred in many regions of my country, and the problem of regional compound air pollution characterized by ozone, fine particulate matter (PM2. 5 ) and acid rain has become increasingly prominent. As important precursors of ozone and secondary organic particulate matter, volatile organic compounds (Volatile Organic Compounds, VOCs) play an extremely important role in atmospheric chemical reactions. At the same time, most VOCs are highly irritating and toxic. Such as benzene is listed as the first carcinogen, n-hexane, heptane and octane can affect the human central nervous system. VOCs mainly come from painting, printing, shoemaking, chemical production and pharmaceutical industries.

In most industries, the composition of VOCs in exhaust gas is not fixed, and the concentration will fluctuate greatly. When the RTO process is used, the temperature of the RTO oxidation chamber will exceed the design temperature. The current mainstream technology:

1. High-temperature bypass, to discharge part of the high-temperature flue gas directly, and control the temperature of the oxidation chamber and regenerator not to exceed the temperature. The high-temperature bypass also has the following problems: (1) The size of the pipeline is large, which requires heat preservation and increases equipment investment; (2) The regulating valve needs to be resistant to high Consider heat preservation and material issues; (4) Reduce RTO heat recovery efficiency.

2. Low-temperature bypass, direct part of the exhaust gas into the oxidation chamber to reduce the temperature of the oxidation chamber. It can solve some of the problems existing in the high-temperature bypass, but there are still the following problems: (1) VOCs are delayed in combustion, causing the regenerator to overheat; (2) The temperature of the oxidation chamber drops rapidly, resulting in a decrease in treatment efficiency.

Contents of the invention

In order to overcome the deficiencies of the above-mentioned prior art, an adjustment process using purified gas recirculation is proposed to achieve the first purpose to solve the problems existing in the above two processes; the second purpose is to improve the purification efficiency of RTO.

The technical scheme adopted in the present invention is: a temperature regulation system of an RTO oxidation furnace, comprising a regenerator A, a regenerator B, a regenerator C, an induced draft fan and a chimney connected on the waste gas pipeline, wherein: heat storage Chamber A, regenerator B and regenerator C are all connected to the oxidation chamber, and regenerator A, regenerator B and regenerator C are respectively connected to the induced draft fan and the chimney through an outlet valve to form a purification circuit; the induced draft fan passes through a The intake valve is connected to the regenerator A, regenerator B and regenerator C to form a purge pipeline; the induced draft fan is connected to the oxygen chamber or the intake end of the exhaust gas pipeline through a regulating valve to form a circulating cooling circuit .

Further, the front end of the waste gas pipeline entering the regenerator A is also connected with a blower.

Furthermore, the front end of the exhaust gas pipeline entering the blower is also provided with an air mixing device, and the induced draft fan is connected to the air mixing device through a regulating valve to form a circulating cooling circuit.

The adjustment process of the above-mentioned temperature adjustment system comprises the following steps:

A. Regenerative combustion, VOCs exhaust gas enters the regenerator A through the exhaust gas pipeline and is heated by the high-temperature regenerator, then enters the oxidation chamber for combustion, and the high-temperature purified gas after combustion enters the regenerator B to heat the regenerator;

B． To purify the exhaust, the regenerator in the regenerator B is heated, and the purified gas is discharged to the chimney through the induced draft fan of the purified gas pipeline after the temperature is lowered;

C． Circular purging, part of the purified gas enters the regenerator C of the exhaust gas in the previous stage through the purge pipeline, and the residual exhaust gas is blown into the oxidation chamber for combustion; Introduce low-temperature purified gas into the oxidation chamber to reduce the temperature of the oxidation chamber to the normal operating temperature.

Further, in step C, when the temperature of the oxidation chamber exceeds 850° C., the regulating valve is opened to obtain gas from the circulation cooling circuit, thereby reducing the temperature of the oxidation chamber.

Further, the total amount of purified gas recirculation from the induced draft fan that participates in the circulation and cooling loop and the purge pipeline is less than 20% of the exhaust gas volume treated by RTO.

Further, the total amount of purified gas recirculation from the induced draft fan participating in the circulation and cooling loop and the purge pipeline is less than 40% of the exhaust gas volume treated by RTO.

Compared with the prior art, the beneficial effect of the present invention is: the temperature regulation system of the RTO oxidation furnace of the present invention enables the exhaust gas to enter the RTO regenerator through the switching valve, and after being heated by the regenerator, enter the oxidation chamber for combustion, and after combustion The high-temperature purified gas then enters the regenerator to heat the regenerator, and after the purified gas cools down, it is discharged to the chimney through the induced draft fan. When the temperature in the RTO oxidation chamber is overheated, part of the purified gas is introduced into the oxidation chamber to adjust the temperature of the oxidation chamber. The main factor causing overtemperature in the oxidation chamber is the high content of VOCs in the exhaust gas. Part of the purified gas can also be mixed with the exhaust gas to reduce the VOCs content in the exhaust gas, and the mixed gas enters the RTO for processing.

Generally speaking, when the overtemperature of the RTO oxidation chamber exceeds the normal operating temperature of the RTO by more than 850°C, the circulation cooling circuit is started to circulate and replenish air to ensure the normal operation of the system. Introduce part of the purified gas into the oxidation chamber or mix with the exhaust gas, and control the flow of the purified gas by adjusting the valve after the induced draft fan or after the induced draft fan. The flow rate of the purified gas should be less than 40% of the RTO processing capacity, and the optimal amount should be less than 20% of the RTO processing capacity. Introduce part of the purified gas into the oxidation chamber, and use the low temperature of the purified gas to adjust the temperature of the oxidation chamber. Introduce part of the purified gas to mix with the exhaust gas to reduce the content of VOCs and adjust the temperature of the oxidation chamber.

In summary, the temperature regulation system of the RTO oxidation furnace of the present invention and its technology have set up three regenerators, and these three regenerators are jointly connected to the combustion chamber, and the first two air intake regenerators will be purified The purified gas is output through the induced draft fan and the chimney, and is fully burned through the regenerator C and the combustion chamber at the same time, and the induced draft fan returns the gas to the combustion chamber or the gas mixing device through the circulating cooling circuit for supplementation, ensuring that the entire The temperature of the RTO oxidation furnace works normally.

Description of drawings

Figure 1 is a schematic diagram of the negative pressure operation of the RTO system, and the recirculated purified gas directly enters the RTO oxidation chamber;

Figure 2 is a schematic diagram of the negative pressure operation of the RTO system and the mixing of recirculated purified gas and exhaust gas;

Figure 3 is a schematic diagram of the positive pressure operation of the RTO system, and the recirculated purified gas directly enters the RTO oxidation chamber;

Figure 4 is a schematic diagram of the positive pressure operation of the RTO system and the mixing of recirculated purified gas and exhaust gas;

Among them: 1-exhaust gas pipeline, 2-regenerator A, 3-regenerator B, 4-regenerator C, 5-oxidation chamber, 6-blower, 7-regulating valve, 8-induced fan, 9- Chimney, 10-purification circuit, 11-air mixing device, 12-purge pipeline, 13-circulation cooling circuit, 14-inlet valve, 15-outlet valve.

detailed description

In order to deepen the understanding of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments, which are only used to explain the present invention and do not limit the protection scope of the present invention.

As shown in Figure 1, a temperature regulation system of an RTO oxidation furnace includes a regenerator A2 connected to the waste gas pipeline 1, a regenerator B3, a regenerator C4, an induced draft fan 8 and a chimney 9, wherein: The heat chamber A2, the regenerator B3 and the regenerator C4 are all connected to the oxidation chamber 5, and the regenerator A2, the regenerator B3 and the regenerator C are respectively connected to the induced draft fan 8 and the chimney 9 through an air outlet valve 15 to form a purification circuit 10 The induced draft fan 8 is respectively connected to the regenerator A2, the regenerator B3 and the regenerator C4 through an inlet valve 14 to form a purge pipeline 12; the induced draft fan 8 is connected to the oxygen chamber 5 through a regulating valve 7 or The intake end of the exhaust gas pipeline 1 forms a circulating cooling loop 13 .

In the above embodiment, a blower 6 may be connected to the front end of the waste gas pipeline 1 entering the regenerator A2, and the induced draft fan 8 is connected to the oxidation chamber 5 through a regulating valve 7 to form a circulating cooling circuit 13 . An air mixing device 11 may also be provided at the front end where the waste gas pipeline 1 enters the blower 6 . In the above embodiments, the induced draft fan 8 is connected to the air mixing device 11 through a regulating valve 7 to form a circulating cooling circuit 13 . Both of these two connection relationships have good usage effects.

Example 1

As shown in Figure 1, the exhaust gas enters the regenerator A through the exhaust gas pipeline 1, and after being heated by the high-temperature regenerator, it enters the oxidation chamber 5 for combustion, and the high-temperature purified gas after combustion enters the regenerator B to heat the heat storage body, the purified gas after cooling passes through the purified gas pipeline 10, and is discharged to the chimney 9 through the induced draft fan 8. Part of the flue gas passes through the purge pipeline 12 and enters the regenerator C where the waste gas is fed in the previous stage, blowing the residual waste gas into the oxidation chamber 5 for combustion. When the oxidation chamber 5 is overheated, the regulating valve 7 is opened, and the low-temperature purified gas is introduced into the oxidation chamber 5, and the temperature of the oxidation chamber 5 is lowered to the normal operating temperature.

Example 2

As shown in Figure 2, the exhaust gas enters the regenerator A through the exhaust gas pipeline 1, and after being heated by the high-temperature regenerator, it enters the oxidation chamber 5 for combustion, and the high-temperature purified gas after combustion enters the regenerator B to heat the heat storage body, the purified gas after cooling passes through the purified gas pipeline 11, and is discharged to the chimney 9 through the induced draft fan 10. Part of the flue gas passes through the purge pipeline 7, enters the regenerator C where the waste gas is fed in the previous stage, and blows the residual waste gas into the oxidation chamber 5 for combustion. When the oxidation chamber 5 is overheated, the regulating valve 7 is opened, and the low-temperature purified gas enters the gas mixing device 11 to mix with the exhaust gas to reduce the concentration of VOCs in the exhaust gas, thereby reducing the temperature of the oxidation chamber 5 to the normal operating temperature.

Example 3

As shown in Figure 3, the exhaust gas enters the regenerator A from the blower 6 through the exhaust gas pipeline 1. After being heated by the high-temperature regenerator, it enters the oxidation chamber 5 for combustion, and the high-temperature purified gas after combustion enters the regenerator B again. Heat the thermal storage body, and the cooled purified gas passes through the purified gas pipeline 10 and is discharged to the chimney 9 . Part of the flue gas is passed through the blowing pipeline 12 by the induced draft fan 8, and enters the regenerator C where the waste gas is fed in the previous stage, and the residual waste gas is blown into the oxidation chamber 5 for combustion. When the oxidation chamber 5 is overheated, the regulating valve 7 is opened, and part of the low-temperature purified gas enters the oxidation chamber 5 by the induced draft fan 8, and the temperature of the oxidation chamber 5 is lowered to the normal operating temperature.

Example 4

As shown in Figure 4, the exhaust gas enters the regenerator A from the blower 2 through the exhaust gas pipeline 3, and after being heated by the high-temperature regenerator, it enters the oxidation chamber 5 for combustion, and the high-temperature purified gas after combustion enters the regenerator B again. Heat the thermal storage body, and the cooled purified gas passes through the purified gas pipeline 10 and is discharged to the chimney 9 . Part of the flue gas is passed through the blowing pipeline 12 by the induced draft fan 8, and enters the regenerator C where the waste gas is fed in the previous stage, and the residual waste gas is blown into the oxidation chamber 5 for combustion. When the oxidation chamber 5 is overheated, the regulating valve 7 is opened, and part of the low-temperature purified gas enters the gas mixing device 11 by the induced draft fan 8, and is mixed with the exhaust gas to reduce the concentration of VOCs in the exhaust gas, thereby reducing the temperature of the oxidation chamber 5 to the normal operating temperature.

The adjustment process of the above-mentioned temperature adjustment system comprises the following steps:

A. Regenerative combustion, VOCs exhaust gas enters the regenerator A through the exhaust gas pipeline 1 and is heated by the high-temperature regenerator, then enters the oxidation chamber for combustion, and the high-temperature purified gas after combustion enters the regenerator B to heat the regenerator;

B． To purify the exhaust, part of the purified gas in the regenerator B is discharged to the chimney through the induced draft fan of the purified gas pipeline;

C． Circular purging, part of the purified gas in the regenerator B enters the regenerator C where the exhaust gas is fed in the previous stage through the purge pipeline, and the residual exhaust gas is blown into the oxidation chamber for combustion; when the oxidation chamber is overheated, open the regulating valve, from The induced draft fan or heat mixing device introduces low-temperature purified gas into the oxidation chamber to reduce the temperature of the oxidation chamber to the normal operating temperature.

In step C, when the temperature of the oxidation chamber exceeds 850° C., the regulating valve is opened to obtain gas from the circulation cooling circuit, thereby reducing the temperature of the oxidation chamber.

In the above embodiment, the total amount of purified gas recirculation from the induced draft fan that participates in the circulation cooling circuit and the purge pipeline is less than 20% of the amount of waste gas treated by the RTO. The best embodiment is the circulation cooling circuit and the purge pipe The total amount of purified gas recirculation in the road is less than 40% of the waste gas treated by the RTO.

The embodiments of the present invention disclose preferred embodiments, but are not limited thereto. Those skilled in the art can easily comprehend the spirit of the present invention based on the above-mentioned embodiments, and make different extensions and changes. But as long as it does not deviate from the spirit of the present invention, it is within the protection scope of the present invention.

Claims (7)

1. A temperature regulation system for an RTO oxidation furnace, characterized in that it includes a regenerator A (2), a regenerator B (3), and a regenerator C (4) connected to the exhaust gas pipeline (1) , induced draft fan (8) and chimney (9), wherein: regenerator A (2), regenerator B (3) and regenerator C (4) are all connected to oxidation chamber (5), regenerator A ( 2), regenerator B (3), and regenerator C (4) respectively connect the induced draft fan (8) and the chimney (9) through an outlet valve (15) to form a purification circuit (10); the induced draft fan (8) respectively Connect the regenerator A (2), regenerator B (3) and regenerator C (4) through an inlet valve (14) to form a purge pipeline (12); the induced draft fan (8) passes through a The regulating valve (7) is connected to the oxygen chamber (5) or the intake end of the waste gas pipeline (1) to form a circulating cooling circuit (13). 2. The temperature regulation system of an RTO oxidation furnace according to claim 1, characterized in that: the front end of the waste gas pipeline (1) entering the regenerator A (2) is also connected with a blower (6). 3. A temperature regulating system for an RTO oxidation furnace according to claim 1 or 2, characterized in that: the front end of the waste gas pipeline (1) entering the blower (6) is also equipped with a gas mixing device (11), and the induced draft fan (8) Connect the gas mixing device (11) through a regulating valve (7) to form a circulating cooling circuit (13). 4. according to the temperature regulation process of claim 3 temperature regulation system, comprise the steps: A. Regenerative combustion, VOCs exhaust gas enters the regenerator A through the exhaust gas pipeline and is heated by the high-temperature regenerator, then enters the oxidation chamber for combustion, and the high-temperature purified gas after combustion enters the regenerator B to heat the regenerator; B． To purify the exhaust, the regenerator in the regenerator B is heated, and the purified gas is discharged to the chimney through the induced draft fan of the purified gas pipeline after the temperature is lowered; C． Circular purging, part of the purified gas enters the regenerator C of the exhaust gas in the previous stage through the purge pipeline, and blows the residual exhaust gas into the oxidation chamber for combustion; Introduce low-temperature purified gas into the oxidation chamber to reduce the temperature of the oxidation chamber to the normal operating temperature. 5. The temperature adjustment process according to claim 4, characterized in that: in step C, when the temperature of the oxidation chamber exceeds 850°C, the regulating valve is opened to obtain gas from the circulating cooling circuit, thereby reducing the temperature of the oxidation chamber. 6. The temperature adjustment process according to claim 5, characterized in that: the total amount of purified gas recirculation from the induced draft fan participating in the circulating cooling circuit and purging pipeline is less than 20% of the exhaust gas volume treated by RTO. 7. The temperature adjustment process according to claim 6, characterized in that: the total amount of purified gas recirculated from the induced draft fan to participate in the circulating cooling circuit and the purge pipeline is less than 40% of the exhaust gas volume treated by RTO.