An adsorption and desorption device and a treatment method for treating light hydrocarbon VOCs-containing waste gas

Abstract

The application relates to the adsorption and desorption technical field and discloses an adsorption and desorption device and a treatment method for treating light hydrocarbon VOCs waste gas, which comprises an inlet flame arrester, one end of the inlet flame arrester is fixed with a light hydrocarbon VOCs waste gas inlet, the other end of the inlet flame arrester is fixed with a plurality of air draft fans through Y-shaped pipelines, the air draft fans are fixed with adsorption and desorption devices through pipelines, a plurality of functional layers are arranged in the adsorption and desorption devices, the functional layers comprise adsorption and desorption layers, heat preservation and cold preservation layers and condensation and heat exchange layers, oil-water separators are fixed in the condensation and heat exchange layers of the adsorption and desorption devices through pipelines. Through the unique adsorption and desorption device structure design, the pipeline arrangement is greatly simplified, the device land occupation area is effectively reduced, the investment cost is reduced, the temperature control is guaranteed, the safety hidden danger caused by high temperature is avoided, and the problems of space and high investment cost are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of adsorption and desorption technology, in particular to an adsorption and desorption device for treating light hydrocarbon VOCs-containing waste gas and a treatment method. BACKGROUND

[0002] The current light hydrocarbon VOCs-containing waste gas treatment focuses on the petrochemical industry, such as petroleum refining, petrochemical industry, organic chemical industry, coal chemical industry, coking chemical industry, and oil storage and handling. The treatment technology mainly includes recovery and destruction. Recovery technology refers to the recovery and utilization of light hydrocarbon VOCs in waste gas through condensation, absorption, adsorption, membrane separation, etc. Destruction technology refers to the decomposition of light hydrocarbon VOCs that are difficult to recover into water and carbon dioxide by direct combustion, regenerative thermal combustion (RTO), regenerative catalytic combustion (RCO), etc. In practical application, in order to achieve the expected treatment effect, a combination of multiple technologies is generally used to achieve complementary and collaborative effect among different technologies to meet the emission standard requirements of light hydrocarbon VOCs-containing waste gas. Recovery technology, especially adsorption method which plays a key role in emission reduction, is more in line with the requirements of ecological green and sustainable development. However, with the continuous in-depth research of scholars at home and abroad on adsorption technology, the constraints are becoming more and more prominent.

[0003] The current adsorption and desorption device has the following problems: on the one hand, due to the design of the device itself, organic matter components will gradually accumulate in the adsorbent, not only reducing the adsorption efficiency, but also affecting the desorption efficiency, resulting in a significant reduction in the overall adsorption and desorption effect of the device; on the other hand, although the device is used to treat pollution, it also consumes a large amount of water and electricity resources, and continuously purifies water and generates electricity, which also continuously emits carbon dioxide, and cannot achieve real energy saving and carbon reduction. Therefore, in order to ensure the long-term stable and efficient operation of the adsorption and desorption device, high adsorption efficiency, complete desorption effect, and real energy saving and carbon reduction, it is crucial to design an adsorption and desorption device for treating light hydrocarbon VOCs-containing waste gas and a treatment method that meets the above conditions.

[0004] According to the disclosure number CN115671937A, it discloses a kind of based on solar condensation adsorption in oil and gas crude oil recovery device, the device includes condensing unit (condensing unit contains absorption refrigeration unit and solar heat collecting unit in it), adsorption unit, oil-water separator and oil tank, adsorption unit is connected with condensing unit, condensing unit and adsorption unit are also respectively connected with oil-water separator, oil-water separator is connected with oil tank, high-temperature oil gas is input into condensing unit, condensate liquid is input into oil-water separator, uncondensed oil gas is input into adsorption unit, adsorption unit carries out adsorption and condensation treatment to oil gas, then input into oil-water separator, oil-water separator inputs the crude oil separated out into oil tank, and completes crude oil recovery.The device recovery rate is high, utilizes solar heating, reduces certain amount of fossil resource consumption, but device still needs to set up electric auxiliary heater, and structure is complex, and land area is relatively large, investment and operating cost are relatively high.

[0005] According to the disclosure number CN106731466A, it discloses a kind of recyclable VOCs exhaust gas adsorption vacuum desorption treatment system, the processing system includes at least one adsorption tower device, adsorption tower device includes adsorption tower, adsorption tower liner is equipped with adsorbent, adsorption tower top is equipped with exhaust pipe and exhaust valve, adsorption tower bottom is equipped with with exhaust pipe and inlet valve, adsorption tower is equipped with the jacket for heating adsorption tower outside, the jacket and adsorption tower liner are equipped with vent, and the exhaust pipe, inlet pipe, vent of adsorption tower all extend out of the jacket;Exhaust pipe side is connected with fan by one-way valve and switch valve, and the outlet of fan is connected with desorption tail gas treatment device.The device can realize the reuse of adsorbent, and the energy consumption is low when adsorbent is desorbed, and the desorption gas volume is small, and the safety is high, and the exhaust gas concentration is high, and direct combustion or condensation recovery solvent is used, so that processing cost is low.But the heat source used in the system is steam or hot oil, if heat source is steam, to keep the system stable during desorption, it needs to constantly input high-temperature steam, which will increase the overall energy consumption;If heat source is hot oil, although it can keep the system stable during desorption for a long time, because hot oil cools down slowly, it will affect the subsequent adsorption efficiency, and it is not worth the loss, and now our country controls the use of combustion method to treat VOCs more and more strictly, this method is not suitable for current ecological environment development demand.

[0006] According to the disclosure number CN111821963A, it discloses a kind of organic waste gas adsorbent vacuum desorption method, the method includes heating outer tank and catalytic tank, heating outer tank left and right two sides wall are fixed cover with sealing cover, sealing cover inner wall is fixedly connected with heating plate, is fixedly inserted with desorption tank in heating outer tank inner cavity vertically downward, multiple equidistant distribution heat pipes are fixedly connected in the inner wall of desorption tank.The method is by vacuum pump work, the waste gas in desorption tank is sent to drive box by suction pipe by blowing pipe, the blowing impeller in drive box is rotated at high speed, to drive stirring rod to the material in the inner cavity of desorption tank is fully stirred, although this can improve desorption effect and efficiency, without motor drive, but this way is only suitable for large processing capacity low concentration project, for small and medium processing capacity project is not applicable.And this method can easily cause damage to the material in the inner cavity of desorption tank, shorten the service life of adsorbent, indirectly increase processing cost.

[0007] According to the disclosure number CN111298597A, it discloses a kind of new high-efficiency vacuum desorption system complete device and waste gas treatment method, the method includes vacuum desorption device, RCO catalytic combustion device, heat recovery desorption device and PLC control box, its characterized in that vacuum desorption device gas outlet and RCO catalytic combustion device are connected by first pipeline, and the gas inlet is provided with heat recovery desorption device, heat recovery desorption device and RCO catalytic combustion device are connected by second pipeline, PLC control box is connected with vacuum desorption device, RCO catalytic combustion device and heat recovery desorption device etc., vacuum desorption device includes desorption kettle, and the bottom of desorption kettle is provided with jacket oil heating device.Although the method can be the tail gas after RCO combustion into vacuum thermal desorption kettle by heat recovery device, overall device will not have tail gas discharge, but than atmospheric pressure desorption temperature is high, in order to keep the temperature in desorption kettle constant, thereby keep high-efficiency desorption, need to continue to heat oil, this in turn increases the desorption energy consumption, and adsorption and desorption adopt ex situ treatment, this also increases the number of equipment, control difficulty and complexity, and floor area.

[0008] According to the disclosure number CN218189694U, a kind of active carbon vacuum desorption box of heat energy recovery can be disclosed, the vacuum desorption box includes box, placing disc is fixedly installed in the inside of box, heating box is fixedly installed in the inner chamber bottom of box, steam outlet pipe is connected at the top of box, heat energy recovery mechanism is equipped on the outside wall of box, heat energy recovery mechanism and steam outlet pipe are communicated, the bottom of heat energy recovery mechanism is connected with water inlet pipe, another end of water inlet pipe and heating box are communicated.The water solution that is preheated to the inside of heating box by heat energy recovery mechanism in the vacuum desorption box, the temperature of water solution is raised, to shorten the time of water solution boiling in heating box interior, to reach the purpose of energy saving, and the steam that is discharged enters into heat energy recovery mechanism, can accelerate steam with gas molecule condensation, facilitate to recover gas molecule.And the top of box is equipped with pressure control mechanism, pressure control mechanism can guarantee that there is sufficient steam in the inside of box during active carbon desorption process, make steam fully heat active carbon, avoid steam directly through steam outlet pipe and discharge.But the equipment system resistance is big, steam needs to be constantly replenished, and week and again, this part of steam also becomes waste gas containing VOCs, instead of increasing additional processing capacity, practicality is not strong.

[0009] According to the disclosure number CN218653715U, a kind of self-heat vacuum desorption waste gas treatment equipment is disclosed, the equipment includes adsorption tower, vacuum pump, condenser and liquid storage tank;The adsorption tower includes tower body and internal inner shell, the space between tower body and inner shell is formed into jacket layer, and the inner shell and jacket layer are filled with adsorbent;The side wall of tower body is also provided with inner gas inlet, inner exhaust port and inner desorption port communicated with inner shell, outer gas inlet, outer exhaust port and outer desorption port communicated with jacket layer, inner desorption port and outer desorption port are connected with vacuum pump;Condenser is connected with vacuum pump and liquid storage tank;Valve is installed on inner gas inlet, inner exhaust port, outer gas inlet, outer exhaust port and desorption pipeline.Although the equipment can stagger adsorption process and desorption process in inner shell and jacket layer, to reduce system operation risk, reduce operating energy consumption, but the heat generated is limited to the efficiency of adsorption and desorption, and with the difference of the position of active carbon, heat is not uniform, and the adsorbent in jacket layer is also replaced with cumbersome inconvenience.

[0010] According to the disclosure number CN213901972U, a solar photovoltaic power supply organic vapor condensation adsorption recovery system is disclosed, which comprises a cover shell, a recovery tank is fixedly connected to the bottom of the cover shell, two fixed plates are fixedly connected to the top of the cover shell, a fixed cylinder is fixedly connected to the lower end of each of the two fixed plates, a gas guide pipe is communicated with the side wall of the fixed cylinder near the upper end, and the gas guide pipe penetrates through the side wall of the cover shell. The system can effectively utilize the waste heat generated during condensation, improve the utilization rate of energy, reduce the cost of enterprises, and can also scrape the organic liquid attached in the fixed cylinder into the recovery tank, reduce the waste of resources, and improve the recovery effect of the device on organic vapor, and increase the heat dissipation area of the device, thereby improving the condensation efficiency. Although this method can effectively adsorb and recover organic vapor, it is only suitable for small-scale projects. Otherwise, if the adsorption VOCs treatment capacity is large or the concentration is high, the adsorbent will be quickly saturated. If the desorption process is not considered at this time, the adsorbent needs to be replaced frequently, which greatly increases the operating cost.

[0011] In summary, the adsorption and desorption devices and treatment methods in the prior art have various limitations in the field of adsorption and desorption of light hydrocarbon VOCs waste gas treatment, mainly including: complex process operation, limited treatment effect, it is difficult to achieve the designed adsorption and desorption effect, complicated adsorbent replacement, relatively high investment and operating cost, and cannot achieve true energy saving and carbon reduction.

[0012] Therefore, it is urgent to develop a new adsorption and desorption device for light hydrocarbon VOCs waste gas treatment that can solve or avoid the above problems. SUMMARY

[0013] In view of the deficiencies of the prior art, the present application provides an adsorption and desorption device and treatment method for light hydrocarbon VOCs waste gas treatment, which solves the problems of unstable temperature control, high energy consumption, large equipment area and poor safety in the process of light hydrocarbon VOCs waste gas treatment.

[0014] In order to achieve the above object, the present application is implemented by the following technical scheme: An adsorption and desorption device for light hydrocarbon VOCs waste gas treatment, comprising an inlet flame arrester, one end of the inlet flame arrester is fixed with a light hydrocarbon VOCs waste gas inlet, the other end of the inlet flame arrester is fixed with a plurality of air suction machines through Y-shaped pipelines, the air suction machines are fixed with adsorption and desorption devices through pipelines, a plurality of functional layers are arranged in the adsorption and desorption devices, the functional layers include adsorption and desorption layers, heat preservation and cold insulation layers and condensation heat exchange layers, oil-water separators are fixed in the condensation heat exchange layers of the adsorption and desorption devices through pipelines, vacuum pumps are arranged in one side of the adsorption and desorption layers of the adsorption and desorption devices through pipelines, outlet flame arresters are fixed in the other side of the adsorption and desorption layers of the adsorption and desorption devices through pipelines, oil pumps and liquid pumps are fixed in the oil-water separators through Y-shaped pipelines, cold water cold insulation storage tanks and hot water heat preservation storage tanks are fixed in the heat preservation and cold insulation layers of the adsorption and desorption devices through Y-shaped pipelines, and an energy supply assembly is arranged on one side of the hot water heat preservation storage tank.

[0015] Preferably, the energy supply assembly includes energy storage batteries, a wind energy heating system and a solar energy heating system, the energy storage batteries are connected between the Y-shaped pipelines and the hot water heat preservation storage tank, the wind energy heating system and the solar energy heating system are connected with the hot water heat preservation storage tank through Y-shaped pipelines, and the wind energy heating system and the solar energy heating system are connected with the energy storage batteries through Y-shaped pipelines.

[0016] Preferably, the heat preservation and cold insulation layers of the adsorption and desorption devices are arranged in the middle parts of the adsorption and desorption devices, the condensation heat exchange layers of the adsorption and desorption devices are arranged on the outer sides of the heat preservation and cold insulation layers of the adsorption and desorption devices, and the adsorption and desorption layers of the adsorption and desorption devices are arranged on the inner sides of the heat preservation and cold insulation layers of the adsorption and desorption devices.

[0017] Preferably, the Y-shaped pipelines connecting the heat preservation and cold insulation layers, the cold water cold insulation storage tank and the hot water heat preservation storage tank are provided with adjusting valves.

[0018] Preferably, one end of the vacuum pump is connected with the adsorption and desorption layer of the adsorption and desorption device, and the other end of the vacuum pump is connected with the inlet of the air suction machine.

[0019] Preferably, the wind energy heating system and the solar energy heating system adopt wind energy and solar energy to heat and generate electricity for cold water.

[0020] Preferably, the energy storage batteries include but are not limited to lead-acid batteries, lithium ion batteries and sodium ion batteries.

[0021] Preferably, the condensation heat exchange layer and the heat preservation and cold insulation layer of the adsorption and desorption device are in a seamless tank type or a hollow tube type structure, and the adsorption and desorption layers are in a fully closed type, a semi-closed type, an interval closed type or an irregular closed type.

[0022] Preferably, the adsorption and desorption layers of the adsorption and desorption device are both adsorbed by adsorbents, including but not limited to activated carbon, molecular sieve, silica gel, alumina, ion exchange resin and metal organic framework MOFs, and the adsorbent forms include but are not limited to granular, columnar, spherical, flaky, strip and fibrous.

[0023] The adsorption and desorption layers of the adsorption and desorption device are both desorbed by vacuum pumps, including but not limited to dry screw vacuum pump, oil-sealed rotary vane vacuum pump, oil-free scroll vacuum pump, Roots vacuum pump and liquid ring vacuum pump.

[0024] An adsorption and desorption treatment method for treating light hydrocarbon VOCs-containing waste gas, comprising the following steps:

[0025] S1, the light hydrocarbon VOCs-containing waste gas first passes through an inlet flame arrester, and then is introduced by an induced draft fan to the condensation heat exchange layer of the adsorption and desorption device for condensation treatment; part of the water and part of the VOCs components in the light hydrocarbon VOCs-containing waste gas are removed, and the light hydrocarbon VOCs-containing waste gas is cooled at the same time;

[0026] S2, the light hydrocarbon VOCs-containing waste gas after condensation treatment is introduced into an oil-water separator for gas-liquid separation, a part of oil phase and liquid phase are recovered, and then most of the condensed gas is introduced into the adsorption and desorption layers of the adsorption and desorption device, so that the adsorption and desorption can be continuously performed in cross, and the adsorbent of each adsorption and desorption device is switched back to the adsorption state after completing the desorption and desorption, and a cycle is completed;

[0027] S3, a large amount of adsorption heat is generated during adsorption, the temperature of the adsorbent is lowered, and the temperature of the surrounding environment is increased, at this time, the pipeline is connected with the cold water cold storage tank, the pipeline in the heat preservation and cold insulation layer is filled with cold water, and the environmental temperature of the adsorption and desorption device is continuously and stably lowered;

[0028] S4, after the adsorption is completed, most of the organic components in the waste gas are adsorbed by the adsorbent, the separated gas reaches the required pressure reduction, and then is introduced into an outlet flame arrester and then into an exhaust cylinder for standard discharge, and the desorption gas is returned to the inlet of the induced draft fan by a vacuum pump for recycling treatment;

[0029] S5, after the completion of the cycle adsorption, close the adsorption inlet and outlet valve, the adsorption and desorption layer of the adsorption and desorption device switches to the desorption regeneration operation, at this time, it will start to absorb heat, so that the adsorbent temperature rises, the ambient temperature decreases, at this time, the heat preservation and cold insulation layer and the hot water heat preservation tank are connected, the hot water heat preservation tank can be connected with any one of the solar heating system, the wind energy heating system and the energy storage battery according to the situation, so as to ensure that a continuous heat source can be obtained, so that the pipeline of the heat preservation and cold insulation layer is filled with hot water, so as to improve the ambient temperature of the adsorption and desorption device;

[0030] S6, after the completion of the adsorption and desorption, the temperature of the hot water backwater of the heat preservation and cold insulation layer during desorption or the cold water backwater during condensation adsorption will rise and finally flow back to the hot water heat preservation tank for heating to a certain temperature, and then repeated cyclic utilization.

[0031] The application provides an adsorption and desorption device and a treatment method for treating light hydrocarbon VOCs waste gas.

[0032] The application has the following beneficial effects:

[0033] 1、The application has a unique adsorption and desorption device structure, including a condensation heat exchange layer, a heat preservation and cold insulation layer and a three-layer structure of adsorption and desorption layers, which not only greatly simplifies the pipeline arrangement, but also effectively reduces the device area and investment cost. This design makes the adsorption and desorption process more efficient and stable, especially in the adsorption stage, through the intelligent adjustment of the cold water cold insulation layer, the temperature control is guaranteed, and the safety hidden danger caused by high temperature is avoided. Compared with the complicated pipeline design in the prior art, the problem of high space and investment cost is solved.

[0034] 2、The application combines solar energy, wind energy heating system and energy storage battery to realize green and clean energy supply, which not only reduces the dependence on traditional energy, but also ensures the stability of the desorption process through continuous heating. This energy combination ensures that the device can maintain sufficient heat supply during the desorption process, avoids the problem of energy shortage in traditional heating systems, reduces the demand for external energy, and reduces the overall energy consumption and operating cost.

[0035] 3、The application combines the recycling system, condensation method and adsorption and desorption method, which not only ensures the efficiency of the waste gas treatment process, but also effectively reduces environmental pollution. The treated tail gas can meet the strict emission standard, and the recovered product can be completely reused, reducing resource waste. Compared with the single treatment method in the prior art, the application optimizes the treatment process and enhances recycling to achieve the dual goals of resource conservation and environmental friendliness. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 It is the device structure distribution diagram of the application.

[0037] Figure 2 The method steps of the present application are shown in the figure.

[0038] Wherein, 101, inlet flame arrester; 102, air blower; 103, adsorption and desorption device; 104, vacuum pump; 105, oil-water separator; 106, oil pump; 107, liquid pump; 108, cold water cold storage tank; 109, hot water heat preservation tank; 110, energy storage battery; 111, wind energy heating system; 112, solar heating system; 113, outlet flame arrester. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the specification of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0040] Embodiment one:

[0041] Please refer to the drawings Figure 1 The embodiment of the present application provides an adsorption and desorption device for treating light hydrocarbon VOCs waste gas, which comprises an inlet flame arrester 101, one end of the inlet flame arrester 101 is fixed with a light hydrocarbon VOCs waste gas inlet, the other end of the inlet flame arrester 101 is fixed with a plurality of air blowers 102 through Y-shaped pipelines, the air blowers 102 are all fixed with adsorption and desorption devices 103 through pipelines, the adsorption and desorption devices 103 are all provided with a plurality of functional layers inside, the functional layers include adsorption and desorption layers, heat preservation and cold preservation layers and condensation and heat exchange layers, the condensation and heat exchange layers of the adsorption and desorption devices 103 are all fixed with oil-water separators 105 through pipelines inside, one side of the adsorption and desorption layers of the adsorption and desorption devices 103 are all provided with vacuum pumps 104 through pipelines, the other side of the adsorption and desorption layers of the adsorption and desorption devices 103 are all fixed with outlet flame arresters 113 through pipelines, the oil-water separators 105 are both fixed with oil pumps 106 and liquid pumps 107 through Y-shaped pipelines inside, the heat preservation and cold preservation layers of the adsorption and desorption devices 103 are both fixed with cold water cold storage tanks 108 and hot water heat preservation tanks 109 through Y-shaped pipelines, one side of the hot water heat preservation tank 109 is provided with an energy supply assembly;

[0042] The energy supply assembly includes an energy storage battery 110, a wind energy heating system 111, and a solar energy heating system 112, the inside of the energy storage battery 110 is connected with the hot water heat preservation storage tank 109 through a Y-shaped pipeline, the inside of the wind energy heating system 111 and the solar energy heating system 112 are both connected with the hot water heat preservation storage tank 109 through a Y-shaped pipeline, and the inside of the wind energy heating system 111 and the solar energy heating system 112 are both connected with the energy storage battery 110 through a Y-shaped pipeline;

[0043] The heat preservation and cold insulation layers of the adsorption and desorption device 103 are arranged in the middle part of the adsorption and desorption device 103, the condensation and heat exchange layers of the adsorption and desorption device 103 are arranged outside the heat preservation and cold insulation layers of the adsorption and desorption device 103, and the adsorption and desorption layers of the adsorption and desorption device 103 are arranged inside the heat preservation and cold insulation layers of the adsorption and desorption device 103;

[0044] The heat preservation and cold insulation layers of the adsorption and desorption device 103 are connected with the cold water heat preservation storage tank 108 and the hot water heat preservation storage tank 109 through Y-shaped pipes, and are internally provided with an adjusting valve group;

[0045] One end of the vacuum pump 104 is connected with the adsorption and desorption layers of the adsorption and desorption device 103, and the other end of the vacuum pump 104 is connected with the inlet of the air blower 102;

[0046] The wind energy heating system 111 and the solar energy heating system 112 adopt wind energy and solar energy to heat cold water and generate electricity;

[0047] The storage medium of the energy storage battery 110 includes but is not limited to a lead-acid battery, a lithium ion battery, and a sodium ion battery;

[0048] The condensation and heat exchange layers and the heat preservation and cold insulation layers of the adsorption and desorption device 103 adopt a seamless tank type or a hollow pipe type structure, and the adsorption and desorption layers adopt a fully closed type, a semi-closed type, an interval closed type, or an irregular closed type;

[0049] The adsorption and desorption layers of the adsorption and desorption device 103 adopt adsorbents for adsorption, the types of which include but are not limited to activated carbon, molecular sieve, silica gel, aluminum oxide, ion exchange resin, and metal organic framework MOFs, and the adsorbent styles include but are not limited to granular, columnar, spherical, flaky, strip-shaped, and fibrous;

[0050] The adsorption and desorption layers of the adsorption and desorption device 103 adopt vacuum pumps for desorption, the types of which include but are not limited to a dry screw vacuum pump, an oil seal rotary vane vacuum pump, an oil-free scroll vacuum pump, a Roots vacuum pump, and a liquid ring vacuum pump.

[0051] Specifically, the light hydrocarbon VOCs-containing exhaust gas first passes through the inlet flame arrester 101 to prevent external fire sources from causing safety hazards to the system. Subsequently, the exhaust gas is transported by the induced draft fan 102 to the condensation heat exchange layer of the adsorption and desorption device 103. In this stage, the temperature of the exhaust gas is reduced to 5-10°C through heat exchange condensation, thereby effectively reducing the moisture content and the concentration of some VOCs components, reducing the load of the subsequent adsorption and desorption links. In addition, the low-temperature exhaust gas entering the adsorption layer can avoid the decrease of adsorption efficiency caused by rapid temperature rise in the adsorption process, ensuring the stable operation of the system.

[0052] The gas stream after condensation and temperature reduction enters the oil-water separator 105 for gas-liquid separation. This process can recover part of the liquid hydrocarbon substances, wherein the oil phase components are transported by the oil pump 106 to the oil storage tank for recovery, and the liquid phase components are transported by the liquid pump 107 to the sewage treatment system for subsequent treatment. The separated condensed gas enters the adsorption and desorption layer of the adsorption and desorption device 103 for deep purification.

[0053] In the adsorption stage, the gas stream passes through the adsorption and desorption device 103 filled with adsorbent, and the VOCs components are captured by the adsorbent, so that the pollutant concentration of the exhaust gas is reduced to the range meeting the emission standard. In order to ensure the stability of the adsorption process, since a large amount of heat is released during the adsorption process, the temperature of the adsorbent rises, which may affect its adsorption capacity. Therefore, the system continuously reduces the temperature of the adsorption environment by connecting the cold water cold storage tank 108, so as to prevent the temperature of the adsorbent from being too high and ensure the stability of the adsorption effect. At the same time, this cooling mechanism can also indirectly improve the efficiency of the condensation stage, making the pre-stage temperature reduction effect better.

[0054] When the adsorbent reaches the saturation state, the system switches to the desorption mode. At this time, the adsorbent in the adsorption and desorption device 103 needs to be regenerated by heating to release the adsorbed VOCs components, so as to regain the adsorption capacity. Since the desorption process needs to absorb a large amount of heat, the pipeline will be switched to the hot water heat preservation tank 109 for heating. The heat source of the hot water can come from the solar energy heating system 112, the wind energy heating system 111, or the electric heating system provided by the energy storage battery 110, to ensure the continuity of heat supply and make the desorption process more efficient and stable. In addition, the VOCs concentrated gas generated in the desorption process is extracted by the vacuum pump 104 and returned to the inlet of the induced draft fan 102 for recycling treatment, further reducing the pollutant emission.

[0055] The waste gas purified by adsorption is discharged to the exhaust cylinder through the outlet flame arrester 113 after pressure reduction, to ensure that the waste gas discharge meets the environmental protection standards. At the same time, in the entire circulating system, the cold water in the condensation adsorption stage and the hot water return water in the desorption process are all returned to the hot water heat preservation tank 109, and are recycled after reheating, thereby improving the energy utilization rate, reducing energy consumption, and ensuring the economy and environmental protection of the system.

[0056] Embodiment two:

[0057] Please refer to the attached Figure 2 An adsorption and desorption treatment method for treating light hydrocarbon VOCs-containing waste gas, comprising the following steps:

[0058] S1, the light hydrocarbon VOCs-containing waste gas first passes through the inlet flame arrester 101, and then is introduced to the condensation heat exchange layer of the adsorption and desorption device 103 by the induced draft fan 102, to condense and treat the light hydrocarbon VOCs-containing waste gas; part of the water and part of the VOCs components in the light hydrocarbon VOCs-containing waste gas are removed, and the light hydrocarbon VOCs-containing waste gas is cooled at the same time;

[0059] S2, the light hydrocarbon VOCs-containing waste gas after condensation treatment is introduced into the oil-water separator 105 for gas-liquid separation, a part of the oil phase and the liquid phase are recovered, and then most of the condensed gas is introduced into the adsorption and desorption layer of the adsorption and desorption device 103, so that it can be continuously cross-connected, so that the adsorbent of each adsorption and desorption device 103 completes desorption and desorption after switching back to the adsorption state, to complete a cycle;

[0060] S3, a large amount of adsorption heat is generated during adsorption, the temperature of the adsorbent is lowered, and the temperature of the surrounding environment is increased, at this time the pipeline is connected with the cold water preservation tank 108, the pipeline in the heat preservation and cold preservation layer is filled with cold water, and the temperature of the adsorption and desorption device 103 is continuously and stably lowered;

[0061] S4, after adsorption is completed, most of the organic components in the waste gas are adsorbed by the adsorbent, the separated gas reaches the required pressure reduction, and then is discharged into the exhaust cylinder through the outlet flame arrester 113 to meet the standard, and the desorption gas is returned to the inlet of the induced draft fan 102 through the vacuum pump 104 for recycling treatment;

[0062] S5, after the cycle adsorption is completed, the adsorption inlet and outlet valves are closed, and the adsorption and desorption layer of the adsorption and desorption device 103 is switched to desorption regeneration operation, at this time it will start to absorb heat, so that the temperature of the adsorbent is increased and the temperature of the surrounding environment is decreased, at this time the heat preservation and cold preservation layer is connected with the hot water heat preservation tank 109, the hot water heat preservation tank 109 can be connected with any one of the solar heating system 112, the wind energy heating system 111 and the energy storage battery 110 according to the situation, to ensure that a continuous heat source can be obtained, so that the pipeline in the heat preservation and cold preservation layer is filled with hot water, so as to improve the temperature of the adsorption and desorption device.

[0063] S6. After adsorption and desorption are completed, the temperature of the heat preservation and cold preservation layers will increase, whether it is the hot water return during desorption or the cold water return during condensation and adsorption. Finally, they will all flow back to the hot water heat preservation storage tank 109 for heating to a certain temperature and then be repeatedly recycled.

[0064] The specific steps and details of the method are the same as those of the device. Please refer to Part 1 of the embodiment for details. Specific details will not be repeated here.

[0065] Working principle: Waste gas containing light hydrocarbon VOCs first passes through the inlet flame arrester 101, and then is guided by the induced draft fan 102 into the condensation heat exchange layer of the adsorbent-desorber 103 for condensation treatment. The condensation treatment lowers the waste gas temperature to 5℃~10℃, removing some moisture and VOCs components, while simultaneously reducing the load on the adsorbent-desorber 103. The condensed waste gas containing light hydrocarbon VOCs enters the oil-water separator 105 for gas-liquid separation. After recovering the oil and liquid phases, most of the condensed gas is introduced into the adsorption and desorption layers of the adsorbent-desorber 103. After each adsorbent-desorber 103 completes desorption, it switches back to adsorption mode, completing one complete cycle. During adsorption, the pipeline is connected to the cold water insulated storage tank 108. Water flows through the pipeline, reducing the ambient temperature of the adsorption-desorption unit 103. During the desorption process, the pipeline is connected to a hot water insulation storage tank 109. The hot water can be connected to a solar heating system 112, a wind power heating system 111, or an energy storage battery 110 to provide a continuous heat source, ensuring that the hot water in the hot water insulation storage tank 109 fills the pipeline with heat preservation and cold insulation layers. The water flow can be returned to the hot water insulation storage tank 109 for reheating and recycling. The treated exhaust gas is discharged through the outlet flame arrester 113 to ensure that the exhaust gas meets the standards. The condensed oil is transported to the oil storage tank for recycling by the oil pump 106. The condensate is discharged to the sewage treatment system for further treatment by the liquid pump 107.

[0066] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An adsorption desorption apparatus for the treatment of exhaust gases containing light hydrocarbon VOCs, comprising an inlet flame arrester (101), characterized in that, The inlet flame arrester (101) is fixed with a light hydrocarbon VOCs exhaust gas inlet at one end, and is fixed with a plurality of air suction fans (102) at the other end through Y-shaped pipelines, the air suction fans (102) are fixed with adsorption and desorption devices (103) through pipelines, the adsorption and desorption devices (103) are internally provided with a plurality of functional layers, the functional layers include adsorption and desorption layers, heat preservation and cold insulation layers and condensation heat exchange layers, the condensation heat exchange layers of the adsorption and desorption devices (103) are internally fixed with oil-water separators (105) through pipelines, one side of the adsorption and desorption layers of the adsorption and desorption devices (103) is provided with vacuum pumps (104) through pipelines, the other side of the adsorption and desorption layers of the adsorption and desorption devices (103) is fixed with outlet flame arresters (113) through pipelines, the oil-water separators (105) are internally fixed with oil pumps (106) and liquid pumps (107) through Y-shaped pipelines, the heat preservation and cold insulation layers of the adsorption and desorption devices (103) are internally fixed with cold water cold insulation storage tanks (108) and hot water heat preservation storage tanks (109) through Y-shaped pipelines, and one side of the hot water heat preservation storage tank (109) is provided with an energy supply assembly; The outlets of the air suction fans (102) are connected with the inlet of the condensation heat exchange layers of the adsorption and desorption devices (103), and the gas phase outlets of the oil-water separators (105) are connected with the inlets of the adsorption and desorption layers of the adsorption and desorption devices (103). The heat preservation and cold insulation layers of the adsorption and desorption devices (103) are arranged in the middle of the adsorption and desorption devices (103), the condensation heat exchange layers of the adsorption and desorption devices (103) are arranged outside the heat preservation and cold insulation layers of the adsorption and desorption devices (103), and the adsorption and desorption layers of the adsorption and desorption devices (103) are arranged inside the heat preservation and cold insulation layers of the adsorption and desorption devices (103).

2. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 1, characterized in that, The energy supply assembly includes energy storage batteries (110), a wind energy heating system (111) and a solar energy heating system (112), the energy storage batteries (110) are connected with the hot water heat preservation storage tank (109) through Y-shaped pipelines, the wind energy heating system (111) and the solar energy heating system (112) are connected with the hot water heat preservation storage tank (109) through Y-shaped pipelines, and the wind energy heating system (111) and the solar energy heating system (112) are connected with the energy storage batteries (110) through Y-shaped pipelines.

3. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 1, characterized in that, Adjusting valves are arranged in the Y-shaped pipelines connected with the heat preservation and cold insulation layers of the adsorption and desorption devices (103), the cold water cold insulation storage tank (108) and the hot water heat preservation storage tank (109).

4. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 1, characterized in that, One end of the vacuum pump (104) is connected with the adsorption and desorption layers of the adsorption and desorption devices (103), and the other end of the vacuum pump (104) is connected with the inlet of the air suction fan (102).

5. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 2, characterized in that, The wind energy heating system (111) and the solar energy heating system (112) use wind energy and solar energy to heat and generate electricity for cold water.

6. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 2, characterized in that, The storage medium of the energy storage batteries (110) is a lead-acid battery, a lithium ion battery or a sodium ion battery.

7. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 1, characterized in that, The condensation heat exchange layer and the heat preservation and cold insulation layer of the adsorption and desorption device (103) are in a seamless tank type or a hollow tube type structure, and the adsorption and desorption layers are in a fully closed type, a semi-closed type, an interval closed type or an irregular closed type.

8. The adsorption and desorption device for treating light hydrocarbon VOCs-containing exhaust gas according to claim 1, characterized in that, The adsorption and desorption layers of the adsorption and desorption device (103) are adsorbed by adsorbents, and the types of the adsorbents are at least one of activated carbon, molecular sieve, silica gel, alumina, ion exchange resin and metal organic framework MOF, and the shapes of the adsorbents are granular, columnar, spherical, flaky, strip or fibrous. The adsorption and desorption layers of the adsorption and desorption device (103) are desorbed by vacuum pumps, and the types of the vacuum pumps are dry screw vacuum pump, oil seal rotary vane vacuum pump, oil-free scroll vacuum pump, Roots vacuum pump or liquid ring vacuum pump.

9. A method for the treatment of waste gases containing light hydrocarbon VOCs by adsorption and desorption, according to any one of claims 1 to 8, characterized in that, The method comprises the following steps: S1, the light hydrocarbon VOCs-containing waste gas is first introduced into the inlet flame arrester (101), then introduced into the condensation heat exchange layer of the adsorption and desorption device (103) by the induced draft fan (102), and subjected to condensation treatment; part of the water and part of the VOCs components in the light hydrocarbon VOCs-containing waste gas are removed, and the light hydrocarbon VOCs-containing waste gas is cooled at the same time; S2, the light hydrocarbon VOCs-containing waste gas after the condensation treatment is introduced into the oil-water separator (105) for gas-liquid separation, a part of the oil phase and the liquid phase are recovered, and then most of the condensed gas is introduced into the adsorption and desorption layers of the adsorption and desorption device (103) to cross and continuously operate, so that the adsorbent of each adsorption and desorption device (103) completes desorption and desorption after switching back to the adsorption state, and a cycle is completed; S3, a large amount of adsorption heat is generated during adsorption and is released, and the ambient temperature rises, at this time, the pipeline is connected with the cold water cold insulation tank (108), the pipeline in the heat preservation and cold insulation layer is filled with cold water, and the ambient temperature of the adsorption and desorption device (103) is continuously and stably reduced; S4, after the adsorption is completed, most of the organic components in the waste gas are adsorbed by the adsorbent, the separated gas meets the requirements, is reduced in pressure, and then is introduced into the exhaust cylinder through the outlet flame arrester (113) to be discharged outside the standard, and the desorption gas is returned to the inlet of the induced draft fan (102) through the vacuum pump (104) to be recycled; S5, after the cycle adsorption is completed, the adsorption inlet and outlet valves are closed, the adsorption and desorption layers of the adsorption and desorption device (103) are switched to desorption and regeneration operation, the heat preservation and cold insulation layer is connected with the hot water heat preservation tank (109), the hot water heat preservation tank (109) is connected with any one of the solar heating system (112), the wind energy heating system (111) and the energy storage battery (110) in the energy supply assembly according to the situation, so that a continuous heat source is ensured to be obtained, the pipeline in the heat preservation and cold insulation layer is filled with hot water, and the ambient temperature of the adsorption and desorption device is increased; S6, after the adsorption and desorption are completed, whether the hot water backflow during the desorption or the cold water backflow during the condensation adsorption of the heat preservation and cold insulation layer, finally, the backflow is heated to a certain temperature in the hot water heat preservation tank (109) and repeatedly used.

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