Energy-saving efficient aeration system and method for coupling VOCs treatment in UHMWPE fiber industry

Abstract

The invention discloses an energy-saving efficient aeration system and method for coupling VOCs treatment in the UHMWPE fiber industry. The device comprises a dichloromethane tank, a layering tank and a water storage tank which are sequentially connected through pipelines, a liquid inlet in one end, connected with the dichloromethane tank, of the layering tank is provided with a drainage guide pipe and an anti-interference sleeve, the top of the drainage guide pipe extends above a layering interface layer, and the top of the drainage guide pipe is of a two-section split structure; the height between the two sections of split structures is adjustable, the bottom of the drainage guide pipe is connected with a pipeline between the layering tank and the water storage tank, and the anti-interference sleeve surrounds the drainage guide pipe; an aeration power device is arranged in the layering tank and is connected with an air source. According to the method, VOCs treatment can be coupled under the condition that extra aeration power is not needed, dichloromethane in waste gas is efficiently removed, and therefore the VOCs emission amount and the treatment cost are reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy conservation and environmental protection in the UHMWPE fiber industry, and specifically relates to an energy-saving and efficient aeration system and method coupled with VOCs treatment in the UHMWPE fiber industry. Background Art

[0002] In the process of producing ultra-high molecular weight polyethylene (UHMWPE) fibers, a certain amount of dichloromethane pollutants will be released. Once entering the atmosphere, it will evolve into VOCs pollution. If it flows into the water, it will cause organic wastewater pollution. At present, the adsorption recovery method is mainly used for the treatment of VOCs-dichloromethane; the aeration method is used for the treatment of dichloromethane organic wastewater, which is determined by the high pollution and difficulty in degradation of dichloromethane.

[0003] For example, patent 201621405876.5 provides a multi-stage continuous aeration treatment device for dichloromethane wastewater, wherein the aeration device includes an aerator at the bottom of the aeration tank, an aeration fan and an exhaust gas exhaust fan, and the multi-stage overflow aeration will effectively promote the flow of wastewater in the tank, promote the rapid volatilization of dichloromethane, and the tubular aerator with micropores can significantly improve the aeration effect, so that the dichloromethane wastewater can reach the direct discharge standard after three-stage aeration treatment. However, there are also the following defects: in the aeration device, the aeration fan brings the dichloromethane in the wastewater into the air, forming volatile organic compounds (VOCs)-dichloromethane pollution. This pollution not only increases the cost of VOCs treatment, but also the additional aeration fan of the aeration device increases the exhaust air volume, introduces excess air, may increase the risk of explosion, and bring some safety hazards. At the same time, the additional aeration fan will also increase the energy consumption of the system, and gradually increase the operating cost of the equipment. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of how to achieve efficient utilization of energy without providing additional aeration power; at the same time, to solve the problem of reducing VOCs-dichloromethane air volume and treatment cost, and to reduce the safety hazards caused by the introduction of excessive air, and to provide an energy-saving and efficient aeration system and method coupled with VOCs treatment in the UHMWPE fiber industry.

[0005] The technical solution adopted by the present invention is: an energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry, comprising a dichloromethane tank, a stratification tank and a water storage tank connected in sequence by pipelines, a liquid inlet at one end of the stratification tank connected to the dichloromethane tank is provided with a drainage conduit and an anti-disturbance sleeve, the top of the drainage conduit extends above the stratification interface layer, the top of the drainage conduit adopts a two-section split structure, the height between the two sections of the split structure is adjustable, the bottom of the drainage conduit is connected to the pipeline between the stratification tank and the water storage tank, and the anti-disturbance sleeve is surrounded by the outside of the drainage conduit; an aeration power device is provided in the stratification tank, and the aeration power device is connected to an air source.

[0006] In a further preferred structure, the aeration power device is composed of an aeration pipe, the aeration pipe is an enlarged pipe with aeration holes evenly distributed around the pipe, and a drainage hole is arranged at the bottom of the aeration pipe.

[0007] In a further preferred structure, the aeration pipe is connected to an air source via an aeration power interface, and the air source components are nitrogen, dichloromethane and water.

[0008] In a further preferred structure, an aeration baffle is provided at the bottom of the aeration power device to prevent the aeration process from disturbing the stratified interface. The aeration baffle is a concave structure with completely enclosed sides, an opening on the top surface, and a baffle drainage port at the bottom.

[0009] In a further preferred structure, the anti-disturbance sleeve has a sawtooth overflow weir cut on the top and a plurality of cuts evenly distributed on the bottom.

[0010] In a further preferred structure, the two separate sections of the drainage conduit are connected by a sealing pipe thread.

[0011] A further preferred structure is that an anti-disturbance cap is provided in the stratification groove, and the anti-disturbance cap is a stepped structure with two sections, the upper end of which is larger and the lower end is smaller, and a cover plate is provided at the upper end of the stepped structure, and the overall central opening of the anti-disturbance cap is sleeved on the pipeline between the stratification groove and the dichloromethane tank.

[0012] In a further preferred structure, the dichloromethane tank and the water storage tank are respectively provided with liquid level gauges.

[0013] In a further preferred structure, a heating coil is provided in the water storage tank for adjusting the temperature in the water tank.

[0014] A method for an energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry comprises the following steps:

[0015] The stratified mixed liquid enters the cavity from the stratification tank. As the liquid level slowly rises, after a certain period of time, the mixed liquid is statically stratified in the stratification tank, and the stratification interface will be stabilized near the height of the drainage conduit to adjust the height of the water outlet; when the liquid level overflows the anti-disturbance sleeve, the liquid will enter the cavity formed by the anti-disturbance sleeve to ensure that the medium flowing out of the drainage conduit is always water; when the interface layer and stratification effect in the stratification tank are stable, the gas source containing power gas of dichloromethane, water and nitrogen is connected, and after buffering, distribution and static pressure of the liquid column by the aeration power device, aeration is carried out in the area surrounded by the aeration baffle, and the aerated nitrogen and dichloromethane gas are discharged from the stratification tank; the water aerated in the stratification tank flows into the water storage tank to further remove the trace amount of dissolved dichloromethane in the water; the dichloromethane tank, the stratification tank and the water storage tank respectively discharge gas and balance the pressure in each tank.

[0016] The present invention can achieve efficient removal of dichloromethane in waste gas by coupling VOCs treatment without the need for additional aeration power, thereby reducing VOCs emissions and treatment costs. At the same time, by optimizing control parameters, precise control is achieved, avoiding the safety risks caused by the introduction of excessive air. The present invention solves the technical problems existing in the prior art and has multiple technical effects such as energy saving, consumption reduction, and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention;

[0018] Figure 2 It is a schematic diagram of the drainage conduit and anti-disturbance sleeve structure of the present invention;

[0019] Figure 3 It is a schematic diagram of the structure of the aeration power device of the present invention;

[0020] Figure 4 This is a schematic diagram of the anti-disturbance baffle structure of the present invention;

[0021] Figure 5 Detailed diagram of the aeration system of the present invention.

[0022] Among them, V-101-dichloromethane tank; V-102-stratification tank; V-103-water storage tank; 1-liquid level gauge (1-1-first liquid level gauge interface; 1-2-second liquid level gauge interface; 1-3-third liquid level gauge interface; 1-4-fourth liquid level gauge interface); 2-1-first exhaust port; 2-2-second exhaust port; 2-3-third exhaust port; 3-aeration power device (3-1-aeration pipe; 3-2-drain hole; 3-3-aeration power interface); 4-1-first liquid inlet; 4-2-second liquid inlet; 4-3-third Liquid inlet; 4-4-fourth liquid inlet; 5-first pipeline; 6-second pipeline; 7-heating coil; 8-drainage duct (8-1-sealing pipe thread); 9-anti-disturbance sleeve (9-1-sawtooth overflow weir; 9-2-incision); 10-aeration baffle (10-1-baffle drain port); 11-third pipeline; 12-fourth pipeline; 13-temperature sensor; 14-1-first liquid outlet; 14-2-second liquid outlet; 14-3-third liquid outlet; 14-4-fourth liquid outlet; 15-inspection port; 16-anti-disturbance cap. DETAILED DESCRIPTION

[0023] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but they do not constitute a limitation on the present invention.

[0024] Example 1

[0025] like Figure 1 As shown, the present invention provides an energy-saving and efficient aeration system for coupled VOCs control in the UHMWPE fiber industry, comprising a dichloromethane tank V-101, a stratification tank V-102 and a water storage tank V-103 which are connected in sequence by pipelines, a liquid inlet at one end of the stratification tank V-102 connected to the dichloromethane tank V-101 is provided with a drainage conduit 8 and an anti-disturbance sleeve 9, the top of the drainage conduit 8 extends above the stratification interface layer, the top of the drainage conduit 8 adopts a two-section split structure, the height between the two sections of the split structure is adjustable, the bottom of the drainage conduit 8 is connected to the pipeline between the stratification tank V-102 and the water storage tank V-103, and the anti-disturbance sleeve 9 surrounds the outside of the drainage conduit 8; an aeration power device 3 is provided in the stratification tank V-102, and the aeration power device 3 is connected to the air source.

[0026] In some optional embodiments, the gas source used in the present invention is vacuum pump exhaust, which can control the exhaust pressure within the range of 2 to 5 KPa, without the need for an additional power fan to pressurize the gas, thereby achieving multi-stage utilization of energy; the main components of the gas source are nitrogen, dichloromethane, and water, and no additional air is introduced.

[0027] In some optional embodiments, the stratification tank V-102 has the functions of stratification, liquid sealing, and emission reduction, and can stratify the entrained dichloromethane solution in the gas source; at the same time, the upper part of the stratification tank V-102 is water, which also plays a liquid sealing role for the dichloromethane solution at the bottom, further reducing the volatilization of VOCs-dichloromethane.

[0028] In some optional embodiments, such as Figure 3 As shown, a highly efficient aeration power device 3 is integrated inside the layered tank V-102, and the aeration power device 3 includes an aeration pipe 3-1. The aeration pipe 3-1 uses a specially made enlarged pipe, and a total of 23 rows of Φ4mm aeration holes are evenly distributed around it. The spacing between each row of holes is 15mm to ensure uniform dispersion and effective transmission of gas. At the bottom of the pipe, a row of Φ8mm drainage holes 3-2 is specially set, which are also arranged at intervals of 15mm to efficiently discharge liquid.

[0029] In some optional embodiments, such as Figure 3 As shown, an aeration baffle 10 is provided at the lower part of the aeration power device 3. The aeration baffle 10 adopts a concave structure, the side is completely enclosed, the top surface is open, and the bottom is provided with a baffle drain port 10-1. This structure can not only significantly accelerate the escape rate of volatile organic compounds such as dichloromethane in water, greatly simplify the process and complexity of subsequent water treatment, but also effectively prevent the disturbance generated during the aeration process from destroying the original stratification interface, thereby ensuring the stability of the stratification effect.

[0030] In some optional embodiments, such as Figure 2 As shown, the top of the drainage conduit 8 extends above the stratified interface layer, and the top adopts a two-section split structure, which is connected by a sealing pipe thread 8-1. The upper layer in the stratified tank V-102 is water, and the lower layer is dichloromethane liquid. The height of the water surface layer in the stratified tank can be controlled according to the difference in density of the contained medium to adjust the height of the overflow port, thereby achieving precise control of the highest point of the liquid level and exerting the optimal stratification effect. This structure not only ensures the effective operation of the equipment, but also improves the convenience of operation.

[0031] In some optional embodiments, such as Figure 2 As shown, the anti-disturbance sleeve 9 is a DN250 pipe with a serrated overflow weir 9-1 cut on the top, with a tooth depth of 7mm and a tooth pitch of 20mm; four cutouts 9-2 are evenly distributed on the bottom of the anti-disturbance sleeve 9, with a cutout size of 150x100mm to ensure smooth liquid flow. The serrated overflow weir 9-1 in the system can effectively intercept the foam and suspended matter generated during the aeration process, reduce the overflow water speed, and ensure the water quality of the water storage tank V-103.

[0032] In some optional embodiments, such as Figure 4As shown, in order to further reduce the influence of the disturbance interface during the aeration process, an anti-disturbance baffle cap 16 is provided in the stratification tank V-102. The anti-disturbance baffle cap 16 is a two-section stepped structure with a large upper end and a small lower end, and a cover plate is provided at the upper end of the stepped structure. The central opening of the anti-disturbance baffle cap 16 is sleeved on the pipeline (third pipeline 11) between the stratification tank V-102 and the dichloromethane tank V-101. The anti-disturbance baffle cap 16 can effectively prevent water from entering the dichloromethane tank V-101 due to untimely stratification.

[0033] In some optional embodiments, such as Figure 5 As shown, a heating coil 7 and a temperature sensor 13 are provided in the water storage tank V-103. The main pipe size of the heating coil 7 is Φ50mm, and the branch pipe size is Φ25mm, which can give full play to the maximum efficiency of heat exchange. The temperature sensor monitors the temperature in the water storage tank V-103 in real time. The heating coil 7 is connected to an external cut-off valve or a regulating valve, which is interlocked with the temperature sensor. The function of accurately controlling the temperature in the water storage tank can be achieved by adjusting the parameters of the heat source. Under normal circumstances, the control temperature is most suitable at 35°C, which takes into account the characteristic that the solubility of dichloromethane in water decreases with increasing temperature. If the temperature of the water storage tank V-103 is too high, the volatilization of dichloromethane in the stratification tank V-102 will be aggravated. Therefore, the present invention reduces the volatilization of dichloromethane and maintains the stable operation of the entire system. In addition, according to the changes in seasons and ambient temperature, the temperature of the heating coil 7 can be flexibly adjusted to meet actual needs. When the temperature is low in winter, the temperature of the heating coil 7 can be appropriately increased; while when the temperature is high in summer, it can be appropriately reduced.

[0034] In some optional embodiments, both the dichloromethane tank V-101 and the water storage tank V-103 are provided with a liquid level meter 1, which can be interlocked with a pump, a valve, etc. to realize automatic liquid level control.

[0035] In some optional embodiments, such as Figure 5As shown, the dichloromethane tank V-101, the layering tank V-102 and the water storage tank V-103 are all cylindrical structures, and all internal components are made of 316L stainless steel. The dichloromethane tank V-101 is a device for containing dichloromethane, the layering tank V-102 is a device for separating dichloromethane and water, and the water storage tank V-103 is a device for containing water. The external structure of the dichloromethane tank V-101 includes a first liquid outlet 14-1, a first liquid inlet 4-1, a first exhaust port 2-1, and two liquid level gauge ports, namely the first liquid level gauge port 1-1 and the second liquid level gauge port 1-2; the internal structure is a cavity. The external structure of the stratified tank V-102 includes two liquid outlets, namely the second liquid outlet 14-2 and the third liquid outlet 14-3, two liquid inlets, namely the second liquid inlet 4-2 and the third liquid inlet 4-3, one second exhaust port 2-2, one inspection port 15, and one aeration power interface 3-3; the internal structure includes an anti-disturbance cap 16, an aeration pipe 3-1, an aeration baffle 10, and an anti-disturbance sleeve 9. The external structure of the water storage tank V-103 includes one fourth liquid outlet 14-4, one fourth liquid inlet 4-4, one third exhaust port 2-3, two liquid level gauge ports, namely the third level gauge port 1-3 and the fourth level gauge port 1-4, one temperature sensor interface, and two heating coil interfaces; the internal structure is a cavity, and the heating coil 7 is installed in the cavity. The dichloromethane tank V-101, the layering tank V-102 and the water storage tank V-103 are connected by pipelines. Specifically, the dichloromethane tank V-101 is connected to the layering tank V-102 through the third pipeline 11, the layering tank V-102 is connected to the water storage tank V-103 through the first pipeline 5, the first liquid outlet 14-1 of the dichloromethane tank V-101 is connected to the fourth pipeline 12, and the fourth liquid outlet 14-4 of the water storage tank V-103 is connected to the second pipeline 6. Among them, the pipe opening heights of the first liquid inlet 4-1 in the dichloromethane tank V-101 and the fourth liquid inlet 4-4 in the water storage tank V-103 are precisely designed according to the density of the contained medium combined with the principle of communicating vessels.

[0036] Example 2

[0037] A method for coupling an energy-saving and efficient aeration system for VOCs treatment in the UHMWPE fiber industry comprises the following steps: a stratified mixed liquid enters a cavity from a second liquid inlet 4-2 or a third liquid inlet 4-3 of a stratification tank V-102, and as the liquid level slowly rises, after a certain period of time, the mixed liquid is allowed to stand in the stratification tank V-102 and stratify, and the stratification interface is stabilized near the height of a drainage conduit 8, wherein the drainage conduit 8 is a two-section split structure, and then the sealing pipe thread 8-1 is further screwed, to adjust the height of the water outlet; when the liquid level overflows the anti-disturbance sleeve 9, the liquid will enter the cavity formed by the anti-disturbance sleeve 9 through the zigzag overflow weir flow 9-1, and finally it can be ensured that the medium flowing out of the drainage conduit 8 is always water; the second liquid outlet 14-2 in the stratification tank V-102 is provided with an anti-disturbance baffle 16, so it can always be ensured that the medium flowing into the dichloromethane tank V-101 from it is dichloromethane; when the interface layer and stratification effect in the stratification tank V-102 are stable, the aeration power interface 3- 3. The gas source contains power gas of dichloromethane, water and nitrogen. This power gas generally carries liquid dichloromethane and water, and the pressure is generally 1kPa to 2kPa. After being buffered, distributed and subjected to static pressure of liquid column by the aeration power device 3, aeration is performed in the area surrounded by the aeration baffle. The nitrogen and dichloromethane gas are discharged from the second exhaust port 2-2 in the stratification tank V-102. The water aerated in the stratification tank V-102 flows into the water storage tank V-103 from the third liquid outlet 14-3. The water storage tank V-103 is filled with water. A heating coil 7 is installed in the cavity of tank V-103, and the heating coil 7 is interlocked with the temperature sensor 13 and the external valve for adjusting, so as to maintain the temperature of the water in the water storage tank V-103 and further remove the trace amount of dissolved dichloromethane in the water, so as to ensure the water quality of the outlet water; in addition, the dichloromethane tank V-101, the stratification tank V-102 and the water storage tank V-103 are respectively provided with a first exhaust port 2-1, a second exhaust port 2-2 and a third exhaust port 2-3 for discharging gas and balancing the pressure in each tank.

[0038] The aeration system of the present invention realizes the effective separation of dichloromethane and water, and successfully avoids the additional introduction of power gas, saves the energy required for providing power, and reduces the risk of air mixing into the aeration system. The present invention achieves technical effects in multiple aspects such as energy saving, consumption reduction and safety, and has significant environmental and economic benefits.

[0039] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. An energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry, comprising a dichloromethane tank (V-101), a stratification tank (V-102) and a water storage tank (V-103) connected in sequence by pipelines, characterized in that: A drainage conduit (8) and an anti-disturbance sleeve (9) are provided at the liquid inlet of one end of the stratification tank (V-102) connected to the dichloromethane tank (V-101); the top of the drainage conduit (8) extends above the stratification interface layer; the top of the drainage conduit (8) adopts a two-section split structure; the height between the two sections of the split structure is adjustable; the bottom of the drainage conduit (8) is connected to the pipeline between the stratification tank (V-102) and the water storage tank (V-103); the anti-disturbance sleeve (9) surrounds the outside of the drainage conduit (8); an aeration power device (3) is provided in the stratification tank (V-102); the aeration power device (3) is connected to an air source.

2. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1 is characterized by: The aeration power device (3) is composed of an aeration pipe (3-1), wherein the aeration pipe (3-1) is an enlarged pipe with aeration holes evenly distributed around the pipe, and a drainage hole (3-2) is arranged at the bottom of the aeration pipe (3-1).

3. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 2 is characterized by: The aeration pipe (3-1) is connected to an air source via an aeration power interface (3-3), and the air source components are nitrogen, dichloromethane and water.

4. An energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1 or 2, characterized in that: An aeration baffle (10) is arranged at the bottom of the aeration power device (3) to prevent the aeration process from disturbing the stratified interface. The aeration baffle (10) is a concave structure with completely enclosed sides, an opening on the top surface, and a baffle drainage port (10-1) at the bottom.

5. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1 is characterized by: The anti-disturbance sleeve (9) has a sawtooth overflow weir (9-1) cut on the top and a plurality of cutouts (9-2) evenly distributed on the bottom.

6. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1 is characterized by: The two separate structures of the drainage conduit (8) are connected by a sealing pipe thread (8-1).

7. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1 is characterized by: An anti-interference baffle (16) is arranged in the stratification tank (V-102), and the anti-interference baffle (16) is a two-section stepped structure with a larger upper end and a smaller lower end, and a cover plate is arranged at the upper end of the stepped structure. The anti-interference baffle (16) has an overall central opening and is sleeved on the pipeline between the stratification tank (V-102) and the dichloromethane tank (V-101).

8. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1 is characterized by: The dichloromethane tank (V-101) and the water storage tank (V-103) are respectively provided with liquid level meters (1).

9. The energy-saving and efficient aeration system coupled with VOCs treatment in the UHMWPE fiber industry according to claim 1, characterized in that: The water storage tank (V-103) is provided with a heating coil (7) for adjusting the temperature in the water tank.

10. The method of energy-saving and efficient aeration system coupled with VOCs treatment in UHMWPE fiber industry according to claim 1, characterized in that: The following steps are involved: The stratified mixed liquid enters the cavity from the stratification tank (V-102), and as the liquid level slowly rises, after a certain period of time, the mixed liquid is statically stratified in the stratification tank (V-102), and the stratification interface is stabilized near the height of the drainage conduit (8), and the height of the water outlet is adjusted; when the liquid level overflows the anti-disturbance sleeve (9), the liquid enters the cavity formed by the anti-disturbance sleeve (9), ensuring that the medium flowing out of the drainage conduit (8) is always water; when the interface layer and the stratification effect in the stratification tank (V-102) are stable, the gas is connected The source contains power gas of dichloromethane, water and nitrogen, which is aerated after being buffered, distributed and subjected to liquid column static pressure by an aeration power device (3), and the aerated nitrogen and dichloromethane gas are discharged from a stratification tank (V-102); the water aerated in the stratification tank (V-102) flows into a water storage tank (V-103) to further remove trace amounts of dissolved dichloromethane in the water; the dichloromethane tank (V-101), the stratification tank (V-102) and the water storage tank (V-103) respectively discharge gas and balance the pressure in each tank.

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