WO2021232576A1

WO2021232576A1 - Optical fiber preform sintering waste gas treatment system and treatment method thereof

Info

Publication number: WO2021232576A1
Application number: PCT/CN2020/102939
Authority: WO
Inventors: 刘勇; 王龙飞; 李凡; 眭立洪; 施国旗
Original assignee: 江苏永鼎股份有限公司
Priority date: 2020-05-09
Filing date: 2020-07-20
Publication date: 2021-11-25
Also published as: CN111644020A; CN212915090U

Abstract

An optical fiber preform sintering waste gas treatment system and a treatment method thereof. The treatment system comprises a Venturi washing tower (1), a filler washing tower (2), a circulating tank (3), fans (4), an air pipe (5), and a chimney (6). The Venturi washing tower (1) and the filler washing tower (2) are respectively vertically fixed on the circulating tank (3); the air pipe (5) is communicated with the top of the Venturi washing tower (1); air inlet ends of the fans (4) are communicated with the top of the filler washing tower (2), and air outlet ends of the fans (4) are communicated with the chimney (6); spraying liquid is sprayed in the Venturi washing tower (1), and an alkali solution circulates in the filler washing tower (2). The waste gas treatment system is high in absorption efficiency, and two-stage absorption of the Venturi washing tower (1) and the filler washing tower (2) is used, so that tail gas emission is ensured to be lower than the strictest national emission standard.

Description

Optical fiber preform sintering waste gas treatment system and treatment method thereof

Technical field

The application belongs to the field of optical fiber production and manufacturing, and in particular relates to an optical fiber preform sintering waste gas treatment system and a treatment method thereof.

Background technique

The optical fiber preform industry has always mainly adopted the "alkali cleaning chlorine/power wave scrubber + absorption tower" process mode for the waste gas treatment after sintering. However, in the actual operation process, there are many problems, such as large floor space and absorption Low efficiency, easy to be blocked, not conducive to safety and personnel health and other shortcomings. Under normal circumstances, the pollutant in the gas is chlorine. The chlorine-containing waste gas and air from sintering, gas holders, etc. are collected through the air duct and discharged to the sintering waste gas treatment system. The exhaust gas flows from top to bottom in the reverse spray section of the power wave, and the lye is injected into the air flow from bottom to top, so that the momentum of the lye and the gas is balanced, thus forming a layer of foam in the area where the gas passes. This area is a layer of strong turbulence, and the liquid surface in this area is renewed quickly, so the dynamic wave scrubber can effectively absorb the exhaust gas. At the same time, it can cool the exhaust gas and remove dust. The exhaust gas after temperature removal and dust removal enters the lye absorption tower. The chlorine-containing waste gas is absorbed again with lye in the caustic washing tower, and the exhaust gas after reaching the standard is discharged through the chimney.

However, the existing technology generally has low absorption efficiency. The existing technology cannot achieve the ideal disassembly and washing effect, which is not conducive to safety and health. Since there is no siphon effect of the Venturi, it is impossible to form a stable negative pressure in the upstream air duct, such as in the case of a fan and other equipment failure. If a certain amount of air extraction cannot be maintained, the highly toxic gas in the air duct will escape to the surrounding space, such as in the workshop, which poses great safety hazards and risks. The existing technology is not energy-saving and environmentally friendly, consumes a large amount of water, and is not economical. It occupies a large area, is complicated to operate, has a wide structural layout, complex on-site installation, and the system is easy to be blocked in operation. Inability to remove a large amount of pollutants, whether it is gas or dust, greatly increases the load of the filler caustic washing tower, and the filler is relatively easy to block, resulting in high operating costs.

Summary of the invention

The technical problem to be solved by the present invention is: in order to solve the shortage of waste gas treatment after sintering in the optical fiber preform industry in the prior art, an optical fiber preform sintering waste gas system and a treatment method thereof are provided.

The technical solutions adopted by the present invention to solve its technical problems are:

An optical fiber preform sintering waste gas treatment system, comprising a venturi washing tower, a packing washing tower, a circulation tank, a fan, a wind pipe and a chimney, the venturi washing tower and the packing washing tower are respectively vertically fixed on the circulation tank The air pipe is connected to the top of the Venturi scrubber, the air inlet end of the fan is communicated with the top of the packing scrubber, the air outlet end of the fan is communicated with the chimney, and the Venturi scrubber is sprayed There is spray liquid, and alkali solution circulates in the packing washing tower. Driven by the fan, the exhaust gas enters from the air pipe and passes through the venturi washing tower, circulation tank, and packing washing tower in turn, after being purified by the The chimney exhausts the atmosphere.

In one of the embodiments, it further includes a spray assembly. The spray assembly includes a spray pump and a spray head connected to the spray pump. The spray head is fixed above the throat of the Venturi scrubber.

In one of the embodiments, the spray assembly further includes a spray head fixed in the packing washing tower.

In one of the embodiments, the inlet end of the spray pump is connected to the circulation tank, and the outlet end is connected to the spray pump.

In one of the embodiments, the alkaline solution is an alkaline solution with a concentration of 30%.

In one of the embodiments, the circulation tank is connected with a regulating tank and a water source, and the circulation tank is also provided with a conductivity meter with a preset threshold value. The conductivity meter measures the soluble salt concentration in the circulation tank to reach the required value At the threshold value, the circulation tank discharges a certain amount of liquid in the tank to the adjustment tank, and the water source supplements the same amount of water to enter the circulation tank.

In one of the embodiments, a pressure sensor is installed on the air pipe, the pressure sensor is connected to the fan, and the fan adjusts the speed according to the pressure of the air pipe measured by the pressure sensor.

In one of the embodiments, a PH detector is also provided in the circulation tank.

In one of the embodiments, an air detector is also provided on the top of the packing washing tower.

A processing method of an optical fiber preform sintering waste gas treatment system. The treatment system includes a venturi washing tower, a packing washing tower, a circulation tank, a fan, a wind pipe and a chimney. The venturi washing tower and the packing washing tower are respectively fixed vertically On the circulation tank, the air pipe is in communication with the top of the venturi scrubber, the air inlet end of the fan is in communication with the top of the packing scrubber tower, the outlet end of the fan is in communication with the chimney, and the venturi A spray liquid is sprayed in the washing tower, and an alkali solution is circulated in the packing washing tower. The treatment method includes the following steps:

Step 10. Chlorine-containing waste gas and air are collected through the air pipe and discharged to the venturi scrubber;

Step 20, the exhaust gas contacts the spray liquid in the venturi throat to complete the preliminary purification;

Step 30, the waste gas after preliminary purification enters the packing washing tower through the circulation tank, and is again absorbed and neutralized by the circulating alkali solution, and the purified waste gas reaches the allowable emission standard;

Step 40: The purified exhaust gas is discharged into the atmosphere through the chimney after passing through the fan.

The beneficial effects of the present invention are: the optical fiber preform sintering waste gas treatment system of the present invention has high absorption efficiency, adopts two-stage absorption of Venturi scrubber and packing scrubber to ensure that tail gas emissions are lower than the most stringent national emission standards; it is beneficial to safety, Healthy, due to the siphon effect of the Venturi, a stable negative pressure can be formed in the upstream air duct in the event of a fan failure, and a small amount of air can be maintained. The hazardous gas in the air duct will not escape to the surrounding space such as workshops and workshops; this system It can also be used as an emergency absorption device for chlorine. When a large amount of chlorine is discharged, chlorine reacts with alkali to release a lot of heat, so it cannot be directly absorbed by a packed tower. Venturi scrubbers are especially suitable for large amounts of high-concentration, exothermic pollutants or particulates. In addition, there is sufficient amount of lye stored in the lye circulation tank to neutralize the absorbed chlorine; the process control is perfect, the water inflow, drainage, and alkali are all automatically controlled, and the wastewater discharge concentration is stable; the area is small , Venturi scrubber and packing scrubber are all placed on the top of the lye circulation tank. The structure is compact and the site installation is simple; it is not easy to be blocked. The Venturi scrubber is used as a pretreatment equipment to remove a large amount of pollutants, whether it is gas or dust. , Reduce the load of the packing washing tower and prevent the packing from clogging.

Description of the drawings

The technical solution of the present application will be further described below with reference to the drawings and embodiments.

FIG. 1 is a schematic diagram of the structure of an optical fiber preform sintering waste gas treatment system according to an embodiment of the present application;

Fig. 2 is a schematic flow chart of the processing method of the optical fiber preform sintering waste gas processing system according to the embodiment of the present application.

Detailed ways

It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other if there is no conflict.

In the description of this application, it should be understood that the terms "center", "vertical", "horizontal", "upper", "lower", "front", "rear", "left", "right", " The orientation or positional relationship indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and The description is simplified, rather than indicating or implying that the pointed device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the protection scope of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of these features. In the description of the invention, unless otherwise specified, the meaning of "multiple" means two or more.

In the description of this application, it should be noted that the terms "installation", "connection", and "connection" should be understood in a broad sense, unless otherwise clearly specified and limited. For example, it can be a fixed connection or a detachable connection. Connected or integrally connected; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication between two components. For those of ordinary skill in the art, the specific meaning of the above-mentioned terms in this application can be understood through specific circumstances.

The technical solutions of the present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

FIG. 1 is a schematic diagram of the structure of an optical fiber preform sintering waste gas treatment system according to an embodiment of the present application; FIG. 2 is a schematic flowchart of a processing method of the optical fiber preform sintering waste gas treatment system according to an embodiment of the present application.

Please refer to Figure 1, an optical fiber preform sintering waste gas treatment system, including a Venturi scrubber 11, a filler scrubber 22, a circulation tank 3, a fan 4, a wind pipe 5 and a chimney 6, a Venturi scrubber 1 and a filler scrubber 2 are fixed vertically on the circulation tank 3, the air pipe 5 is connected with the top of the venturi scrubber 1, the inlet end of the fan 4 is connected with the top of the packing scrubber 2, the outlet end of the fan 4 is connected with the chimney 6, and the venturi scrubber 1. There is a spray liquid in the spray, and an alkali solution circulates in the packing washing tower 2. Driven by the fan 4, the chlorine-containing waste gas and air from sintering, gas holders, etc. are collected and discharged to the system through the air pipe 5. The waste gas enters through the air pipe 5 and passes through the Venturi scrubber 1, the circulation tank 3, and the filler in turn. After the tower 2 is purified, the atmosphere is exhausted from the chimney 6.

Under normal circumstances, the pollutant in the exhaust gas is chlorine. The exhaust gas first enters the Venturi scrubber 1, the gas pollutants and the sprayed liquid violently contact in the throat of the Venturi scrubber 1, mass transfer occurs, and a large amount of gas pollutants are absorbed into the spray liquid. The preliminarily purified gas enters the packing scrubber 2 and is re-absorbed and neutralized by the circulating lye, and the sintering waste gas finally reaches the allowable emission standard.

In order to achieve liquid spraying, in one of the embodiments, a spray assembly is also included. The spray assembly includes a spray pump 7 and a spray head 8 connected to the spray pump 7. The spray head 8 is fixed in the venturi washing tower 1 Above the throat pipe in order to fully spray and purify the exhaust gas in the tower.

In one of the embodiments, the spray assembly further includes a spray head 8 fixed in the packing washing tower 2, through which the waste gas in the tower can be further purified.

In one of the embodiments, the inlet end of the spray pump 7 is connected to the circulation tank 3 and the outlet end is connected to the spray pump 7 to circulate the alkali solution in the packing washing tower 2.

In one of the embodiments, the alkaline solution is an alkaline solution with a concentration of 30%. Packed scrubber 2 uses high-efficiency packing, and the amount of 30% alkali solution added is controlled by ORP. ORP value (oxidation reduction potential) is an important indicator of water quality. Although it cannot independently reflect the quality of water, it can integrate other water quality indicators to reflect the ecological environment in the aquarium system. Simply put, it represents a reduced or oxidized state of the solution. In sewage treatment, the ORP meter is generally used to control the dosage.

The concentration of soluble salts generated by the neutralization reaction can be controlled by a conductivity meter. When the set value is reached, the wastewater will be discharged into the regulating tank, and fresh water will be added to supplement the liquid level. For example, in one of the embodiments, the circulation tank 3 is connected with a regulating tank and a water source, and the circulation tank 3 is also provided with a conductivity meter with a preset threshold. When the conductivity meter measures the soluble salt concentration in the circulation tank 3 to reach the threshold, The circulation tank 3 discharges a certain amount of liquid in the tank to the regulating tank, and the water source supplements the same amount of water to enter the circulation tank 3.

The purified gas passes through the fan 4, and then is discharged into the atmosphere through the chimney 6, and the exhaust gas meets the allowable emission standards. According to the pressure of the upstream air pipe 5, the frequency of guiding the fan 4 is automatically adjusted. This system can also be used as an emergency treatment system in case of a chlorine leak.

In order to realize the automatic adjustment of the frequency of the fan 4, in one of the embodiments, a pressure sensor is installed on the air pipe 5, and the pressure sensor is connected to the fan 4, and the fan 4 adjusts the speed according to the pressure of the air pipe 5 measured by the pressure sensor.

In order to facilitate the control of the dosage of the alkali solution, in one of the embodiments, a pH detector is also provided in the circulation tank 3.

In order to monitor whether the exhaust gas from the system meets the allowable emission standards, in one of the embodiments, an air detector is also provided on the top of the packing scrubber 2.

A processing method of an optical fiber preform sintering waste gas treatment system. The treatment system includes a venturi washing tower 1, a packing washing tower 2, a circulation tank 3, a fan 4, a wind pipe 5 and a chimney 6, a venturi washing tower 1 and a packing washing tower 2 are fixed vertically on the circulation tank 3, the air pipe 5 is connected with the top of the venturi scrubber 1, the inlet end of the fan 4 is connected with the top of the packing scrubber 2, the outlet end of the fan 4 is connected with the chimney 6, and the venturi scrubber 1. There is a spray liquid inside the spray, and an alkali solution circulates inside the packing washing tower 2. Please refer to Figure 2. The treatment method includes the following steps:

Step 10, the chlorine-containing waste gas and air are collected through the air pipe 5 and discharged to the venturi scrubber 1;

Step 20, the exhaust gas and the spray liquid are contacted in the venturi throat to complete the preliminary purification;

In step 30, the preliminary purified waste gas enters the packing washing tower 2 through the circulation tank 3, and is again absorbed and neutralized by the circulating alkali solution, and the purified waste gas reaches the allowable emission standard;

In step 40, the purified exhaust gas passes through the fan 4 and is discharged into the atmosphere through the chimney 6.

The beneficial effects of the present invention are: the optical fiber preform sintering waste gas treatment system of the present invention has high absorption efficiency, adopts the two-stage absorption of the Venturi scrubber 1, the packing scrubber 2, and ensures that the exhaust gas emission is lower than the strictest national emission standard; Safe and healthy. Due to the siphon effect of the Venturi, a stable negative pressure can be formed in the upstream air duct 5 even if the fan 4 fails, keeping a small amount of ventilation, and the hazardous gas in the air duct 5 will not escape to the workshop and workshop. The system can also be used as an emergency absorption device for chlorine gas. When a large amount of chlorine gas is discharged, the chlorine gas reacts with alkali to release a large amount of heat, so it cannot be directly absorbed by a packed tower. The Venturi scrubber 1 is particularly suitable for large, high-concentration, Removal of exothermic pollutants or particulate matter. In addition, there is sufficient amount of lye stored in the lye circulation tank 3 to neutralize the absorbed chlorine; the process is well controlled, and the water intake, drainage, and alkali addition are all automatically controlled. The discharge concentration is stable; it occupies a small area, the Venturi scrubber 1, the filler scrubber 2 are all placed on the top of the lye circulation tank 3, the structure is compact, and the site installation is simple; it is not easy to be blocked, and the Venturi scrubber 1 is used as pretreatment equipment , Remove a large amount of pollutants, whether it is gas or dust, reduce the load of the packing washing tower 2 and prevent the packing from clogging.

Taking the above-mentioned ideal embodiment based on this application as enlightenment, and through the above description, relevant staff can make various changes and modifications without departing from the scope of the technical idea of this application. The technical scope of this application is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

An optical fiber preform sintering waste gas treatment system, which is characterized by comprising a venturi washing tower (1), a packing washing tower (2), a circulation tank (3), a fan (4), a wind pipe (5) and a chimney (6) ), the Venturi scrubber (1) and the packing scrubber (2) are vertically fixed on the circulation tank (3), and the air pipe (5) and the top of the Venturi scrubber (1) The air inlet end of the fan (4) is communicated with the top of the packing scrubber (2), the outlet end of the fan (4) is communicated with the chimney (6), and the venturi scrubber (1) A spray liquid is sprayed inside, and an alkali solution is circulated in the packing washing tower (2). Driven by the fan (4), the exhaust gas enters from the air pipe (5) and passes through the venturi washing tower in turn (1) The circulating tank (3) and the packing washing tower (2) are purified and discharged from the chimney (6) to the atmosphere.
The optical fiber preform sintering waste gas treatment system according to claim 1, further comprising a spray assembly, which includes a spray pump (7) and a spray head (8) connected to the spray pump (7) , The spray head (8) is fixed above the throat of the venturi scrubber (1).
The optical fiber preform sintering waste gas treatment system according to claim 2, wherein the spray assembly further comprises a spray head (8) fixed in the packing washing tower (2).
The optical fiber preform sintering waste gas treatment system according to claim 3, characterized in that the inlet end of the spray pump (7) is connected to the circulation tank (3), and the outlet end is connected to the spray pump (7). ).
The optical fiber preform sintering waste gas treatment system according to claim 1, wherein the alkaline solution is an alkaline solution with a concentration of 30%.
The optical fiber preform sintering waste gas treatment system according to claim 1, characterized in that the circulation tank (3) is connected with a regulating tank and a water source, and the circulation tank (3) is also provided with a preset threshold conductance When the soluble salt concentration in the circulation tank (3) reaches the threshold value measured by the conductivity meter, the circulation tank (3) discharges a certain amount of liquid in the tank to the regulating tank, and the water source supplements the same amount The water enters the circulation tank (3).
The optical fiber preform sintering waste gas treatment system according to claim 1, characterized in that a pressure sensor is installed on the air pipe (5), the pressure sensor is connected to the fan (4), and the fan (4) is based on the pressure The pressure of the air duct (5) measured by the sensor adjusts the speed.
The optical fiber preform sintering waste gas treatment system according to claim 1, wherein a PH detector is also provided in the circulation tank (3).
The optical fiber preform sintering waste gas treatment system according to claim 1, wherein an air detector is also provided on the top of the packing washing tower (2).
A method for processing an optical fiber preform sintering waste gas processing system, characterized in that the processing system includes a venturi washing tower (1), a packing washing tower (2), a circulation tank (3), a fan (4), and a wind pipe (5). ) And a chimney (6), the venturi scrubber (1) and the packing scrubber (2) are respectively vertically fixed on the circulation tank (3), and the air pipe (5) and the venturi scrubber The top of the tower (1) is connected, the inlet end of the fan (4) is communicated with the top of the packing scrubber (2), the outlet end of the fan (4) is communicated with the chimney (6), and the venturi The washing tower (1) is sprayed with spray liquid, and an alkali solution is circulated in the packing washing tower (2). The treatment method includes the following steps:

Step 10. Chlorine-containing waste gas and air are collected through the air pipe (5) and discharged to the Venturi scrubber (1);

Step 20, the exhaust gas contacts the spray liquid in the venturi throat to complete the preliminary purification;

Step 30: The preliminary purified waste gas enters the packing washing tower (2) through the circulation tank (3), and is again absorbed and neutralized by the circulating alkali solution, and the purified waste gas reaches the allowable emission standard;

Step 40: The purified exhaust gas passes through the fan (4) and is discharged into the atmosphere from the chimney (6).