Waste gas treatment system and control method for optical fiber preform OVD deposition

Abstract

The invention discloses an exhaust gas treatment system for optical fiber preform OVD deposition, comprising an exhaust gas treatment device (5), an exhaust gas main pipeline (4), a wind valve actuator (2), and a bypass pipeline (11) provided with a heat converter (13), wherein the heat converter (13) is connected to a waste heat recovery mechanism (16) through a first waste heat circulation pipe (17), and the waste heat recovery mechanism (16) is connected to a waste heat collector (18) through a second waste heat circulation pipe (19), and the waste heat recovery mechanism (16), the waste heat collector (18) and the pressure gauge (12) and bypass electric valve (10) on the bypass pipeline (11), the pressure difference sensor (14) and / or the temperature sensor (15) on the exhaust gas main pipeline (4), and the wind valve actuator (2) are respectively connected to a waste heat control system through lines. The invention can make the OVD deposition device run stably, optimize the effect, and be more energy-saving and environmentally friendly.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber preform OVD deposition, in particular to an exhaust gas treatment system for optical fiber preform OVD deposition and a control method thereof. Background Art

[0002] During the operation of the optical fiber preform OVD system, the exhaust gas treatment device plays a key role in the performance stability of the optical fiber preform system, improving the deposition efficiency and reducing the operating costs. A good exhaust gas treatment effect can ensure the operating stability and lower operating costs of the optical fiber preform OVD system. A good exhaust gas treatment device will make the energy-saving effect more competitive in the market.

[0003] Existing waste gas treatment systems for optical fiber preform OVD deposition are as follows: Figure 1 As shown, multiple groups of exhaust pipes 3 with air valve actuators 2 are installed on the OVD deposition device 1, and electric valves are configured on the air valve actuators 2. The exhaust pipes 3 share a waste gas main pipe 4 and are connected to the waste gas treatment device 5. In order to stabilize the pressure or preheat the waste gas, a bypass control device with an electric heater is currently added to the waste gas main pipe 4. A flange butterfly valve 7 is provided at the connection between the bypass control device and the waste gas main pipe 4, and a first electric valve 6 and a second electric valve 8 are respectively provided on the waste gas main pipe 4 on both sides of the connection; the bypass control device includes a bypass pipe 11 with a bypass electric valve 10 at the outlet, and a pressure gauge 12, a heat converter 13 and an exhaust fan 9 equipped with a control valve are sequentially provided on the bypass pipe 11. When the exhaust gas treatment system equipped with the bypass control device is in use, once the wind pressure in the exhaust gas main pipeline 4 is unstable, the exhaust fan 9 draws the purified cold air in the purification workshop and heats it through the electric heater to provide a heat source for the heat converter 13, and then transports it to the exhaust gas main pipeline 4 along the bypass pipeline 11, thereby taking measures such as pressure stabilization and heating preheating control.

[0004] like Figure 1 Although the exhaust gas treatment system shown solves the problem of wind pressure fluctuation, it is found in the actual operation process that the use of electric heaters leads to increased power consumption and equipment failure rate, which greatly increases the operating cost and equipment maintenance cost, and increases labor intensity and safety risks during high-altitude operations; on the other hand, since the exhaust fan 9 extracts the purified cold air, the air conditioning system in the workshop purification area is in a negative pressure state, which will produce a lot of dust, pollute the quality of optical fiber preforms and other products, and other serious quality problems, and may even lead to serious consequences such as inability to produce. Therefore, this technology needs to be further improved because it is not energy-saving and environmentally friendly, consumes electricity and cold sources of the air conditioning system, and is not economical. Summary of the invention

[0005] The object of the present invention is to provide an exhaust gas treatment system and a control method thereof for optical fiber preform OVD deposition in view of the problems existing in the prior art.

[0006] The purpose of the present invention is to be solved by the following technical solutions:

[0007] A waste gas treatment system for optical fiber preform OVD deposition, comprising a waste gas treatment device, a waste gas main pipeline, a wind valve actuator, and a bypass pipeline with a heat converter, characterized in that: the heat converter is connected to a waste heat recovery mechanism through a first waste heat circulation pipe, the waste heat recovery mechanism is connected to a waste heat collector through a second waste heat circulation pipe, the waste heat recovery mechanism and the waste heat collector are respectively connected to a waste heat control system through lines, and the waste heat control system is respectively connected to a pressure gauge on the bypass pipeline, a bypass electric valve, a pressure difference sensor and / or a temperature sensor and a wind valve actuator arranged on the waste gas main pipeline through lines.

[0008] The differential pressure sensor and / or temperature sensor is arranged at the inlet side of the exhaust gas main pipe.

[0009] The differential pressure sensor and / or temperature sensor is arranged on the exhaust gas main pipeline between the bypass pipeline and the first electric valve.

[0010] The error between the real-time pressure value transmitted by the differential pressure sensor to the waste heat control system and the pressure reference value in the waste heat control system does not exceed ±15Pa.

[0011] The error between the real-time temperature value transmitted by the temperature sensor to the waste heat control system and the temperature reference value in the waste heat control system does not exceed ±3.25°C.

[0012] The heat converter is a gas-liquid heat exchanger or a gas-gas heat exchanger.

[0013] The waste heat collector is connected to the waste heat discharge port of the air compressor / dryer through the air compressor / dryer waste heat collection pipe.

[0014] The waste heat collector is connected to the waste heat outlet of the cooling tower through the waste heat collection pipe of the cooling tower.

[0015] A control method for an exhaust gas treatment system for optical fiber preform OVD deposition, characterized in that the control method comprises the following steps:

[0016] A. When the error between the real-time pressure value transmitted by the differential pressure sensor to the waste heat control system and the pressure reference value range in the waste heat control system exceeds ±15Pa and / or the error between the real-time temperature value transmitted by the temperature sensor to the waste heat control system and the temperature reference value range in the waste heat control system exceeds ±3.25℃,

[0017] B. The waste heat control system determines whether to perform a pressure-increasing operation, a pressure-reducing operation, a temperature-increasing operation, or a temperature-reducing operation on the exhaust gas in the exhaust gas main pipeline according to the real-time value transmitted by the pressure difference sensor and / or the temperature sensor;

[0018] C. The waste heat control system controls the waste heat collector, waste heat recovery mechanism and heat converter to work together and open the bypass electric valve according to the determined operation;

[0019] D. When the real-time pressure value transmitted by the differential pressure sensor to the waste heat control system falls within the pressure reference value range in the waste heat control system and / or the real-time temperature value transmitted by the temperature sensor to the waste heat control system falls within the temperature reference value range in the waste heat control system, the waste heat control system closes the bypass electric valve and cuts off the energy transmission channel between the heat converter and the waste heat collector and waste heat recovery mechanism.

[0020] The waste heat control system in step D will output the processed result to the air valve actuator. After receiving the command, the air valve actuator will perform PID automatic adjustment according to the real-time feedback pulse signal to ensure that the exhaust gas will not adhere to the inner wall of the exhaust duct due to insufficient ventilation or high humidity.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The waste gas treatment system of the present invention eliminates the electric heater, reduces power consumption and equipment operation and maintenance costs, and safety risks of personnel maintenance; the waste heat collector effectively collects and recycles the excess heat in the power system, reduces power consumption and air conditioning cold source consumption, and achieves waste heat from the waste gas not being directly discharged into the atmosphere but being recycled, thereby achieving green and environmentally friendly recycling and improving the quality of OVD products; through pressure and / or temperature control and PID closed-loop adjustment of the air valve actuator, the OVD deposition device can operate stably, with optimized effects and more energy-saving and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Attached Figure 1 It is a schematic diagram of an exhaust gas treatment system for optical fiber preform OVD deposition in the prior art;

[0024] Attached Figure 2 This is a schematic diagram of the exhaust gas treatment system for optical fiber preform OVD deposition of the present invention;

[0025] Attached Figure 3 This is a control principle diagram of the waste heat control system of the present invention.

[0026] Among them: 1—OVD deposition device; 2—air valve actuator; 3—exhaust duct; 4—exhaust gas main duct; 5—exhaust gas treatment device; 6—first electric valve; 7—flange butterfly valve; 8—second electric valve; 9—exhaust fan; 10—bypass electric valve; 11—bypass duct; 12—pressure gauge; 13—heat converter; 14—pressure difference sensor; 15—temperature sensor; 16—waste heat recovery mechanism; 17—first waste heat circulation pipe; 18—waste heat collector; 19—second waste heat circulation pipe; 21—cooling tower waste heat collection pipe; 20—cooling tower; 22—air compressor / dryer; 23—air compressor / dryer waste heat collection pipe. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0028] like Figure 2-3 As shown: an exhaust gas treatment system for OVD deposition of optical fiber preform, comprising a plurality of exhaust ducts 3 with air valve actuators 2 arranged on an OVD deposition device 1, an exhaust gas treatment device 5, an exhaust gas main duct 4, and a bypass duct 11 provided with a heat converter 13, the exhaust ducts 3 share a common exhaust gas main duct 4 and are connected to the exhaust gas treatment device 5, the bypass duct 11 is connected to the exhaust gas main duct 4, a flange butterfly valve 7 is provided at the connection between the bypass duct 11 and the exhaust gas main duct 4, and a first electric valve 6 and a second electric valve 8 are respectively provided on the exhaust gas main duct 4 on both sides of the connection; A bypass electric valve 10, a pressure gauge 12 and a heat converter 13 are sequentially arranged on the waste heat exchanger 13. The heat converter 13 is connected to a waste heat recovery mechanism 16 through a first waste heat circulation pipe 17, and the waste heat recovery mechanism 16 is connected to a waste heat collector 18 through a second waste heat circulation pipe 19. The waste heat recovery mechanism 16 and the waste heat collector 18 are respectively connected to a waste heat control system through lines, and the waste heat control system is respectively connected to the pressure gauge 12 on the bypass pipe 11, the bypass electric valve 10, and a pressure difference sensor 14 and / or a temperature sensor 15 and a wind valve actuator 2 arranged on the exhaust gas main pipe 4 through lines.

[0029] As needed, the pressure difference sensor 14 and / or the temperature sensor 15 are arranged on the inlet side of the exhaust gas main pipe 4; a preferred solution is: the pressure difference sensor 14 and / or the temperature sensor 15 are arranged on the exhaust gas main pipe 4 between the bypass pipe 11 and the first electric valve 6; in addition, as needed, the heat converter 13 adopts a gas-liquid heat exchanger or a gas-to-gas heat exchanger, and the waste heat recovery mechanism 16 provides heat for the heat converter 13 to heat the gas circuit circulation in the heat converter 13.

[0030] In the waste gas treatment system for OVD deposition of optical fiber preform rods of the present invention, the waste heat collector 18 effectively collects and recycles the waste heat energy in the power system. For example, the waste heat collector 18 is connected to the waste heat exhaust port of the air compressor / dryer 22 through the air compressor / drying waste heat collection pipe 23, and the waste heat collector 18 is connected to the waste heat exhaust port of the cooling tower 20 through the cooling tower waste heat collection pipe 21; the valves matching the waste heat recovery mechanism 16, the waste heat collector 18, the first waste heat circulation pipe 17, the second waste heat circulation pipe 19, the air compressor / drying waste heat collection pipe 23, the cooling tower waste heat collection pipe 21 and other pipelines are also controlled by the waste heat control system.

[0031] When the exhaust gas treatment system for OVD deposition of optical fiber preform rods of the present invention is used, the error between the real-time pressure value transmitted to the waste heat control system by the pressure difference sensor 14 and the pressure reference value in the waste heat control system is generally not more than ±15Pa, and the error between the real-time temperature value transmitted to the waste heat control system by the temperature sensor 15 and the temperature reference value in the waste heat control system is generally not more than ±3.25°C.

[0032] A control method for an exhaust gas treatment system for optical fiber preform OVD deposition, the control method comprising the following steps:

[0033] A. When the error between the real-time pressure value transmitted to the waste heat control system by the pressure difference sensor 14 and the pressure reference value range in the waste heat control system exceeds ±15Pa and / or the error between the real-time temperature value transmitted to the waste heat control system by the temperature sensor 15 and the temperature reference value range in the waste heat control system exceeds ±3.25℃,

[0034] B. The waste heat control system determines whether the waste gas in the waste gas main pipe 4 needs to be pressurized, depressurized, heated, or cooled according to the real-time value transmitted by the pressure difference sensor 14 and / or the temperature sensor 15;

[0035] C. The waste heat control system controls the waste heat collector 18, the waste heat recovery mechanism 16 and the heat converter 13 to cooperate and open the bypass electric valve 10 according to the determined operation;

[0036] D. When the real-time pressure value transmitted to the waste heat control system by the pressure difference sensor 14 falls within the pressure reference value range in the waste heat control system and / or the real-time temperature value transmitted to the waste heat control system by the temperature sensor 15 falls within the temperature reference value range in the waste heat control system, the waste heat control system closes the bypass electric valve 10 and cuts off the energy transmission channel between the heat converter 13 and the waste heat collector 18 and the waste heat recovery mechanism 16.

[0037] When the optical fiber preform OVD deposition system of the waste gas treatment system of the present invention is in normal production, the OVD deposition device 1 starts the air valve actuator 2 of the exhaust system, and the glass dust is normally pumped to the waste gas treatment device 5 through the exhaust pipe 3. At this time, the bypass electric valve 10 is in a closed state, and the corresponding waste heat recovery mechanism 16 and the waste heat collector 18 need to work normally. Heat energy can be stored inside the waste heat collector 18; if the wind pressure in the waste gas main pipe 4 is unstable and / or the air pipe temperature is not enough, the pressure difference sensor 14 and / or the temperature sensor 15 on the waste gas main pipe 4 will feed back the signal to the waste heat control system, and the waste heat control system The bypass electric valve 10, the heat converter 13, the waste heat recovery mechanism 16, the waste heat collector 18, etc. are controlled and processed, and the heat in the waste heat collector 18 is quickly transferred to the bypass of the exhaust main pipe 4 through the waste heat recovery mechanism 16 and the heat converter 13 for drying and preheating; and the result after the processing is output to the corresponding air valve actuator 2. After receiving the instruction, the air valve actuator 2 will perform PID automatic adjustment according to the real-time feedback pulse signal to ensure that the corresponding exhaust pipe 3 of the exhaust system will not be attached to the inner wall due to insufficient exhaust or high humidity, affecting the deposition efficiency and product quality of the OVD deposition device 1. In addition, the waste heat energy in the exhaust gas treatment system comes from the collection and energy storage system of excess heat in the power system. In this way, the exhaust gas treatment system is repeatedly switched online and operated normally. The whole process does not affect the normal operation of the OVD deposition device 1, and the switching can be completed in only about 1 minute.

[0038] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention; any technology not involved in the present invention can be realized by existing technologies.

Claims

1. An exhaust gas treatment system for optical fiber preform OVD deposition, comprising an exhaust gas treatment device (5), an exhaust gas main pipeline (4), a wind valve actuator (2), and a bypass pipeline (11) provided with a heat converter (13), characterized in that: The heat converter (13) is connected to the waste heat recovery mechanism (16) through a first waste heat circulation pipe (17), and the waste heat recovery mechanism (16) is connected to the waste heat collector (18) through a second waste heat circulation pipe (19). The waste heat recovery mechanism (16) and the waste heat collector (18) are respectively connected to the waste heat control system through lines, and the waste heat control system is respectively connected to the pressure gauge (12) on the bypass pipe (11), the bypass electric valve (10), and the pressure difference sensor (14) and / or temperature sensor (15) arranged on the exhaust gas main pipe (4), and the air valve actuator (2) through lines; the error between the real-time pressure value transmitted to the waste heat control system by the pressure difference sensor (14) and the pressure reference value range in the waste heat control system does not exceed ±15Pa; the error between the real-time temperature value transmitted to the waste heat control system by the temperature sensor (15) and the temperature reference value range in the waste heat control system does not exceed ±3.25°C.

2. The exhaust gas treatment system for optical fiber preform OVD deposition according to claim 1, characterized in that: The differential pressure sensor (14) and / or the temperature sensor (15) are arranged on the inlet side of the exhaust gas main pipe (4).

3. The exhaust gas treatment system for optical fiber preform OVD deposition according to claim 2, characterized in that: The differential pressure sensor (14) and / or the temperature sensor (15) are arranged on the exhaust gas main pipe (4) between the bypass pipe (11) and the first electric valve (6).

4. The exhaust gas treatment system for optical fiber preform OVD deposition according to claim 1, characterized in that: The heat converter (13) is a gas-liquid heat exchanger or a gas-gas heat exchanger.

5. The exhaust gas treatment system for optical fiber preform OVD deposition according to claim 1, characterized in that: The waste heat collector (18) is connected to the waste heat discharge port of the air compressor / dryer (22) via the air compressor / dryer waste heat collection pipe (23).

6. The exhaust gas treatment system for optical fiber preform OVD deposition according to claim 1, characterized in that: The waste heat collector (18) is connected to the waste heat discharge port of the cooling tower (20) via a cooling tower waste heat collection pipe (21).

7. The control method of the exhaust gas treatment system for optical fiber preform OVD deposition according to any one of claims 1 to 6, characterized in that: The steps of the control method are: A. When the error between the real-time pressure value transmitted by the differential pressure sensor (14) to the waste heat control system and the pressure reference value range in the waste heat control system exceeds ±15 Pa and / or the error between the real-time temperature value transmitted by the temperature sensor (15) to the waste heat control system and the temperature reference value range in the waste heat control system exceeds ±3.25° C., B. The waste heat control system determines whether to perform a pressure increase operation, a pressure reduction operation, a temperature increase operation, or a temperature decrease operation on the waste gas in the waste gas main pipeline (4) according to the real-time value transmitted by the pressure difference sensor (14) and / or the temperature sensor (15); C. The waste heat control system controls the waste heat collector (18), the waste heat recovery mechanism (16) and the heat converter (13) to work in coordination and opens the bypass electric valve (10) according to the determined operation; D. When the real-time pressure value transmitted to the waste heat control system by the pressure difference sensor (14) falls within the pressure reference value range in the waste heat control system and / or the real-time temperature value transmitted to the waste heat control system by the temperature sensor (15) falls within the temperature reference value range in the waste heat control system, the waste heat control system closes the bypass electric valve (10) and cuts off the energy transmission channel between the heat converter (13) and the waste heat collector (18) and the waste heat recovery mechanism (16).

8. The control method of the exhaust gas treatment system for optical fiber preform OVD deposition according to claim 7, characterized in that: The waste heat control system in step D outputs the result of the processing to the air valve actuator (2). After receiving the command, the air valve actuator (2) performs PID automatic adjustment according to the real-time feedback pulse signal to ensure that the exhaust duct (3) will not cause the exhaust gas to adhere to the inner wall of the exhaust duct (3) due to insufficient exhaust or high humidity.

Images