Low-temperature cryogenic efficient VOC (volatile organic compound) condensation recovery device

Abstract

The utility model discloses a low-temperature cryogenic high-efficiency VOC (volatile organic compound) condensation recovery device, which comprises an air inlet liquid separation tank, an induced draft fan, a precooler, a low-temperature liquefier and an activated carbon tank which are sequentially connected, and the lower ends of the air inlet liquid separation tank, the precooler and the low-temperature liquefier are respectively connected with an oil storage tank. The device is used for treating volatile matters such as organic solvents in the chemical industry and the petrochemical industry, the VOC is condensed into liquid by adopting a cryogenic process, the liquid is uniformly recycled, the recycled liquid can be sold as a raw material or a byproduct, the problem of environment-friendly emission is solved, and meanwhile, the income of an enterprise is also increased.

Description

Technical Field

[0001] The utility model relates to the field of VOC treatment, in particular to a low-temperature, deep-cold and high-efficiency VOC condensation recovery device. Background Art

[0002] Most chemical and petrochemical companies are involved in volatile chemicals, organic solvents, etc., and VOC gases will be emitted during the production process. In order to reduce environmental pollution, VOCs must be treated according to environmental protection requirements before they can meet emission standards.

[0003] Common VOC treatment measures include: activated carbon adsorption, RTO furnace incineration, RCO furnace incineration, etc. These treatment processes consume high energy or produce secondary hazardous waste. Since most VOCs are volatiles of raw materials or products, VOCs can be condensed to condense gaseous organic matter in the exhaust gas into liquid, which can be recovered and sold again as raw materials or by-products. Utility Model Content

[0004] In view of the shortcomings of the prior art, the utility model provides a low-temperature, deep-cold and high-efficiency VOC condensation and recovery device, which is applied to common VOC treatment conditions and is used for the treatment of volatile VOCs such as organic solvents in the chemical and petrochemical industries. It adopts a deep-cold process to condense VOC into liquid for unified recovery. The recovered liquid can be sold as raw material or by-product, which solves the problem of environmental emissions and also increases the company's income.

[0005] To achieve the above purpose, the utility model provides the following technical solutions:

[0006] A low-temperature, deep-cold and high-efficiency VOC condensation recovery device comprises an air intake liquid separator tank, an induced draft fan, a precooler, a low-temperature liquefier and an activated carbon tank which are connected in sequence, wherein the lower ends of the air intake liquid separator tank, the precooler and the low-temperature liquefier are respectively connected to an oil storage tank.

[0007] As a further solution of the utility model, an oil-gas separator is provided between the upper end of the low-temperature liquefier and the precooler, and the outlet end of the oil-gas separator is connected to the precooler through a circulation pipeline and then connected to the activated carbon tank.

[0008] As a further solution of the utility model, the low-temperature liquefier is provided with a refrigerator.

[0009] As a further solution of the utility model, the activated carbon canister includes an activated carbon canister A and an activated carbon canister B, and a vacuum pump is arranged between the activated carbon canister A and the activated carbon canister B.

[0010] As a further solution of the utility model, a plurality of regulating valves and flow meters are provided on the connecting pipelines of the air inlet liquid separator tank, the induced draft fan, the precooler, the low-temperature liquefier and the activated carbon tank.

[0011] The utility model has the following beneficial effects:

[0012] The utility model adopts a cryogenic process to condense VOC into liquid for unified recovery. The recovered liquid can be sold as raw material or by-product, thus solving the problem of environmental emission and increasing the income of the enterprise.

[0013] In order to more clearly illustrate the structural features and functions of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural schematic diagram of a low-temperature, deep-cold and high-efficiency VOC condensation recovery device mentioned in the utility model. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the accompanying drawings and related knowledge, and described clearly and completely. Obviously, the described application is only a part of the embodiments of the present invention, rather than all of the embodiments.

[0016] Reference Figure 1 As shown, the utility model provides a low-temperature, deep-cold, and efficient VOC condensation recovery device, comprising an air intake liquid separator 1, an induced draft fan 2, a precooler 3, a low-temperature liquefier 4, and an activated carbon tank connected in sequence, and the lower ends of the air intake liquid separator 1, the precooler 3, and the low-temperature liquefier 4 are respectively connected to an oil storage tank 6;

[0017] In the present invention, the gas containing VOC components first enters the gas inlet liquid separator 1. The main function of this device is to be used as a buffer device. At the same time, it can perform preliminary separation of droplets and mist droplets in the exhaust gas, and the separated liquid is discharged into the oil storage tank 6. The exhaust gas provides system power through the induced draft fan 2, and the induced draft fan 2 draws the exhaust gas from the upstream and sends the exhaust gas to the precooler 3 at the same time; the main function of the precooler 3 is to precool the VOC gas, condense and cool the exhaust gas at room temperature to below 10°C, and condense a part of the high-boiling volatile VOC into liquid, and the condensed liquid is discharged into the oil storage tank.

[0018] exist Figure 1 In the process, the pre-cooled VOC gas is sent to the cryogenic liquefier 4, and the exhaust gas is deeply cooled and condensed through the cryogenic liquefier. The gas temperature can be reduced to -35°C or lower. Different condensation temperatures can be selected according to different components in the VOC. After passing through the cryogenic liquefier, most of the VOC volatiles will be condensed into liquid and discharged into the oil storage tank 6.

[0019] Reference Figure 1As shown, an oil-gas separator 7 is provided between the upper end of the cryogenic liquefier 4 and the precooler 3. The outlet end of the oil-gas separator 7 is connected to the precooler through a circulation pipeline and then to the activated carbon tank. Energy recovery is achieved through a heat exchange pipeline. That is to say, the cold source of the precooler 3 adopts the low-temperature gas deeply cooled in the rear section, and there is no additional cold source consumption, which can save the power consumption of the cold source and is more energy-saving and environmentally friendly.

[0020] Furthermore, the cryogenic liquefier 4 is provided with a refrigerator 8. The cold source of the cryogenic liquid device 4 adopts low-temperature refrigeration for cooling. The low-temperature gas discharged from the cryogenic liquid device 4 returns to the precooler 3 for recycling of cold capacity. As mentioned above, the cold source of the precooler 3 adopts the deep-cold low-temperature gas. The cold gas exchanges heat with the original VOC gas to release cold capacity. The temperature of the cold gas rises to above 0°C and is then sent to the activated carbon adsorption tank at the end as a terminal collection measure to further reduce the VOC content in the exhaust gas.

[0021] Specifically, the cold air exhaust outlet of the low-temperature liquefier 4 is divided into two paths. One path passes through the oil-gas separator 7 and then goes to the precooler 3 for cold recovery, and the other path goes to the activated carbon adsorption tank. A regulating valve is provided on this path, which is interlocked with the precooler temperature to adjust the exhaust volume to prevent a large amount of excessive cold air from entering the precooler 3, causing the precooler 3 temperature to be too low; the cooling capacity of the refrigerator 8 can be interlocked with the operating temperature of the low-temperature liquefier 4 for control and frequency conversion. When the temperature is too low, the output cooling capacity of the refrigerator is reduced, thereby reducing the power consumption and achieving energy-saving effects. Moreover, the exhaust volume of the low-temperature liquefier 4 is interlocked with the temperature of the precooler 3 to avoid the precooler temperature being too low and causing equipment icing.

[0022] Reference Figure 1 As shown, the activated carbon tank includes an activated carbon tank A9 and an activated carbon tank B10, and a vacuum pump 11 is arranged between the activated carbon tank A and the activated carbon tank B. Two sets of activated carbon adsorption tanks are arranged for switching use, one set is adsorbing VOC, and the other set is vacuum desorbing VOC. Alternating use can ensure that the activated carbon has a long adsorption life and meets the long-term stable operation of the device, thereby realizing two sets of activated carbon adsorption tanks in parallel and alternating operation, one set adsorbs and the other set desorbs, ensuring that the activated carbon has a long-term adsorption function, thereby ensuring that the exhaust gas emissions can meet the emission standards. Further preferably, the two sets of adsorption tanks are automatically switched through the control program without manual operation. The activated carbon adsorption tank is designed with a vacuum desorption function, and the desorbed gas is returned to the front air inlet separator tank for secondary condensation treatment. The system can recover more condensate, improve the recovery rate, and be more energy-saving and environmentally friendly.

[0023] Several regulating valves and flow meters are arranged on the connecting pipes of the air inlet separator tank, induced draft fan, precooler, low-temperature liquefier and activated carbon tank. In some embodiments, a flow meter is arranged at the air inlet of the device to monitor the processing capacity of the device. In addition, when the flow fluctuates, the processing capacity of the subsequent equipment can be adjusted in advance to achieve the function of eliminating peaks and troughs; and in the utility model, the refrigeration capacity is adjusted by frequency conversion, and the frequency conversion is interlocked with the operating temperature of the low-temperature liquefier. When the temperature is too low, the output cooling capacity of the refrigerator is reduced. It is further preferred that the operating programs of various equipment, instruments, control valves, etc. are integrated into the PLC through the PLC control program, which can achieve one-button start and automatic control with a high degree of automation.

[0024] The technical principle of the utility model is described above in combination with the specific embodiments, which are only the preferred implementation methods of the utility model. The protection scope of the utility model is not limited to the above embodiments, and all technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. Those skilled in the art can think of other specific implementation methods of the utility model without creative labor, and these methods will fall within the protection scope of the utility model.

Claims

1. A low-temperature, deep-cold and high-efficiency VOC condensation recovery device, characterized in that: It includes an air intake separator tank, an induced draft fan, a precooler, a low-temperature liquefier and an activated carbon tank which are connected in sequence. The lower ends of the air intake separator tank, the precooler and the low-temperature liquefier are respectively connected to an oil storage tank. An oil-gas separator is arranged between the upper end of the low-temperature liquefier and the precooler. The outlet end of the oil-gas separator is connected to the precooler through a circulation pipeline and then connected to the activated carbon tank.

2. A low-temperature, deep-cold and high-efficiency VOC condensation recovery device as claimed in claim 1, characterized in that: The low-temperature liquefier is provided with a refrigerator.

3. A low-temperature, deep-cold and high-efficiency VOC condensation recovery device as claimed in claim 2, characterized in that: The activated carbon tank comprises an activated carbon tank A and an activated carbon tank B, and a vacuum pump is arranged between the activated carbon tank A and the activated carbon tank B.

4. A low-temperature, deep-cold and high-efficiency VOC condensation recovery device as claimed in claim 3, characterized in that: A plurality of regulating valves and flow meters are arranged on the connecting pipelines of the air inlet liquid separator tank, the induced draft fan, the precooler, the low-temperature liquefier and the activated carbon tank.

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