Fuel recovery device and method for dual-fuel engine

Abstract

The invention discloses a dual-fuel engine fuel recovery device and method in the technical field of engine waste gas treatment. The dual-fuel engine fuel recovery device comprises a filter, a heat exchanger, a storage tank and an adsorption tower which are sequentially communicated. A heating device and a condenser are arranged on the adsorption tower, and a gas sensor is arranged on a discharge port of the adsorption tower; according to the invention, the active carbon arranged in the adsorption tower is used for adsorbing the natural gas contained in the waste gas, so that the content of the natural gas in the discharged waste gas is reduced, and it is ensured that the discharge of the waste gas meets the standard; and the heating equipment heats the activated carbon in the adsorption tower by utilizing the heat of the recycled waste gas, so that the natural gas is separated from the activated carbon and is used for recycling the discharged fuel, and the energy is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of engine exhaust gas treatment, and specifically to a fuel recovery device and method for a dual-fuel engine. Background Art

[0002] With the increasing global attention to environmental protection and energy efficiency, dual-fuel engines, as a power device that can use multiple fuels (such as diesel and natural gas or liquefied petroleum gas), have received extensive attention due to their advantages in reducing emissions and improving fuel flexibility; in the actual operation of dual-fuel engines, especially during the startup phase, load changes, or the process of switching from one fuel to another, some fuels are discharged out of the system without complete combustion, resulting in the exhaust gas containing natural gas, which not only wastes fuel but also increases operating costs. Summary of the Invention

[0003] The purpose of the present invention is to provide a fuel recovery device and method for a dual-fuel engine to solve the problem that some fuels are discharged out of the system without complete combustion, resulting in the exhaust gas containing natural gas as mentioned in the above background art.

[0004] To achieve the above purpose, the present invention provides the following technical solution: A fuel recovery device for a dual-fuel engine, comprising: a filter, a heat exchanger, a storage tank, and an adsorption tower connected in sequence;

[0005] The adsorption tower is provided with a heating device and a condenser, and a gas sensor is provided at the discharge port of the adsorption tower; the adsorption tower uses activated carbon to adsorb natural gas in the exhaust gas, and the heating device is used to heat the activated carbon in the adsorption tower with the waste heat recovered by the heat exchanger when the gas sensor detects an increase in the natural gas content in the discharged gas to desorb natural gas.

[0006] Preferably, the heating device includes a working box and a heat exchange pipe provided on the working box, the heat exchange pipe is connected to the heat exchanger, and a circulation pump is provided on the heat exchange pipe.

[0007] Preferably, an electric heating device and a temperature sensor are provided in the working box.

[0008] Preferably, a first partition is provided in the working box, the first partition is used to divide the inner cavity of the working box into an evaporation chamber and a working chamber, the heat exchange pipe is provided in the working chamber, the evaporation chamber is connected to the adsorption tower, the electric heating device is provided in the evaporation chamber, and a delivery pump is provided in the evaporation chamber to deliver the liquid inside the working chamber to the evaporation chamber.

[0009] Preferably, a second partition plate is provided in the working chamber. The second partition plate is used to divide the working chamber into a storage chamber and a heating chamber. The storage chamber and the heating chamber are vertically distributed. An opening is provided on the second partition plate. A baffle for blocking the opening and a driving member for driving the baffle to move are provided on the working box. A liquid level sensor is provided in the heating chamber. The heat exchange pipe and the temperature sensor are both provided in the heating chamber. The storage chamber is communicated with the condenser.

[0010] Preferably, a kit is sleeved on the outer wall of the heat exchange pipe. An opening is provided on the kit. A fan blade is rotatably provided in the kit. The fan blade is used to cool the heat exchange medium passing through the working box in the heat exchange pipe.

[0011] Preferably, an impeller is provided in the heat exchange pipe. A transmission shaft is rotatably provided on the kit. A gear for meshing with the transmission shaft is provided on the shaft of the impeller. The transmission shaft and the shaft of the fan blade are driven by a conveyor belt.

[0012] Preferably, a first solenoid valve is provided at the outlet of the filter. The outlet of the first solenoid valve is respectively connected to the turbine generator and the heat exchanger. The air outlet of the turbine generator is communicated with the inlet of the heat exchanger.

[0013] Preferably, a dual-fuel engine fuel recovery method uses the above-mentioned dual-fuel engine fuel recovery device, including the following steps:

[0014] S1: The exhaust gas discharged from the dual-fuel engine is filtered by the filter, then enters the heat exchanger to be cooled, and then enters the adsorption tower through the storage tank and is adsorbed by the activated carbon in the adsorption tower and then discharged after the natural gas is removed;

[0015] S2: When the gas sensor detects that the natural gas content in the gas discharged from the adsorption tower rises, the storage tank stops transporting the exhaust gas to the adsorption tower. At the same time, the heating device uses the waste gas heat recovered by the heat exchanger to heat water, and the generated steam is introduced into the adsorption tower to desorb the natural gas from the activated carbon. The desorbed gas is condensed by the condenser to separate the steam from the natural gas, and the natural gas is recovered.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. The activated carbon provided in the adsorption tower adsorbs the natural gas contained in the exhaust gas to reduce the natural gas content in the discharged exhaust gas, ensuring that the exhaust gas discharge meets the standards. And the heating device uses the recovered waste gas heat to heat the activated carbon in the adsorption tower to desorb the natural gas from the activated carbon for recovering the discharged fuel, saving energy;

[0018] 2. The heat exchanger absorbs the heat contained in the waste gas to cool the waste gas so that the natural gas adsorbed in the activated carbon will not be desorbed when it passes through the activated carbon, ensuring the normal adsorption of the activated carbon. At the same time, the heating device uses the recovered waste gas heat to heat the activated carbon when desorbing the natural gas, which can achieve the effect of saving energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of the recovery device of the present invention;

[0020] Figure 2 It is a schematic structural diagram of the heating device of the present invention;

[0021] Figure 3 It is a schematic cross-sectional structure diagram of the working box of the present invention;

[0022] Figure 4 For the present invention Figure 3 The enlarged schematic diagram of the structure at A in it.

[0023] In the figure: 1, filter; 2, heat exchanger; 3, storage tank; 4, adsorption tower; 5, heating device; 51, working box; 52, kit; 5201, impeller; 5202, transmission shaft; 5203, conveyor belt; 5204, opening; 5205, fan blade; 53, heat exchange pipeline; 54, first partition; 55, electric heating device; 56, delivery pump; 57, temperature sensor; 58, liquid level sensor; 59, second partition; 510, driving part; 511, baffle; 512, evaporation chamber; 513, storage chamber; 514, heating chamber; 6, turbine generator; 7, condenser; 8, gas sensor; 9, first solenoid valve; 10, circulation pump; 11, second solenoid valve; 12, third solenoid valve; 13, fourth solenoid valve; 14, fifth solenoid valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] Embodiment 1

[0026] Please refer to Figure 1, a fuel recovery device for a dual-fuel engine, comprising: a filter 1, a heat exchanger 2, a storage tank 3 and an adsorption tower 4 (an activated carbon layer is provided inside the adsorption tower 4); the outlet of the filter 1 is communicated with the inlet of the heat exchanger 2 through a first solenoid valve 9 (the outlet of the first solenoid valve 9 is communicated with the inlet of the housing of the heat exchanger 2), the outlet of the heat exchanger 2 is communicated with the inlet of the storage tank 3 (the outlet of the housing of the heat exchanger 2 is communicated with the inlet of the storage tank 3), a second solenoid valve 11 is installed at the outlet of the storage tank 3, a pump is installed at the outlet of the second solenoid valve 11, the outlet of the pump is communicated with the inlet of the adsorption tower 4, and a gas sensor 8 (such as an infrared sensor, for detecting natural gas in the exhaust gas) and a fourth solenoid valve 13 are installed at the discharge port of the adsorption tower 4; a recovery port is provided at the top of the adsorption tower 4, a fifth solenoid valve 14 is provided on the recovery port, and a condenser 7 is provided at the outlet of the fifth solenoid valve 14; the recovery device further includes a heating device 5, the heating device 5 includes a working box 51 and a heat exchange pipe 53 provided on the working box 51, the inlet and outlet of the heat exchange pipe 53 are respectively communicated with the pipe inlet and outlet of the heat exchanger 2, a circulation pump 10 is provided on the heat exchange pipe 53, and the condensate outlet of the condenser 7 is communicated with the working box 51.

[0027] It should be noted that a controller (PLC controller) is installed on the recovery device to control the overall operation of the device according to the set program.

[0028] A fuel recovery method for a dual-fuel engine includes the following steps:

[0029] First, the exhaust gas discharged from the dual-fuel engine is filtered by the filter 1 to remove particulate impurities and dust, then enters the heat exchanger 2 to be cooled, and then enters the storage tank 3 for storage. The stored exhaust gas is transported to the adsorption tower 4 by a pump, and the natural gas is adsorbed by the activated carbon and then discharged.

[0030] Second, during the process of treating the exhaust gas, the gas sensor 8 detects the treated exhaust gas. When it detects that the natural gas content in the gas discharged from the adsorption tower 4 increases, the controller controls the second solenoid valve 11 to close, so that the storage tank 3 stops transporting the exhaust gas to the adsorption tower 4, and closes the fourth solenoid valve 13. At the same time, the third solenoid valve 12 and the fifth solenoid valve 14 are opened. The heating device 5 uses the waste gas heat recovered by the heat exchanger 2 to heat water (the heat exchange medium inside the heat exchange pipe 53 absorbs the heat contained in the waste gas in the heat exchanger 2, and the heated heat exchange medium exchanges heat with the water inside the working box 51 to heat the water. Among them, the heat exchange medium can be water). The generated steam is introduced into the adsorption tower 4 to desorb the natural gas from the activated carbon. The desorbed gas is condensed by the condenser 7, so that the steam is liquefied into condensate and returned to the working box 51 for recycling, used to separate the steam and natural gas, and recover the natural gas.

[0031] Thirdly, when parsing to the preset time (the time for heating the activated carbon is set according to requirements), the controller controls the third solenoid valve 12 and the fifth solenoid valve 14 to close, and opens the second solenoid valve 11 and the fourth solenoid valve 13. At the same time, the controller controls the pump to work to assist the exhaust gas inside the storage tank 3 to enter the adsorption tower 4.

[0032] It should be noted that the condenser 7 is located above the working box 51, so that the condensed water in the condenser 7 flows back into the inside of the working box 51 for recycling under the action of the height difference.

[0033] In this embodiment, as a further optimized solution, please refer to Figure 2 and Figure 3 , a first partition 54 is provided in the inner cavity of the working box 51. The first partition 54 is used to divide the inner cavity of the working box 51 into an evaporation cavity 512 and a working cavity. The evaporation cavity 512 is communicated with the inlet of the adsorption tower 4. An electric heating device 55 (electric heating plate) is provided in the evaporation cavity 512; a second partition 59 is provided in the working cavity. The second partition 59 is used to divide the working cavity into a storage cavity 513 and a heating cavity 514. The storage cavity 513 and the heating cavity 514 are distributed vertically. An opening is provided on the top wall of the second partition 59 to communicate the storage cavity 513 and the heating cavity 514 through the opening. A baffle 511 is slidably provided on the top wall of the second partition 59. A driving member 510 (electric telescopic rod) is installed on the second partition 59. The moving end of the driving member 510 is connected to the baffle 511. The baffle 511 is used to block the opening. A temperature sensor 57 and a liquid level sensor 58 are provided in the inner cavity of the heating cavity 514. The storage cavity 513 is communicated with the condensed water outlet of the condenser 7; a delivery pump 56 is provided in the inner cavity of the evaporation cavity 512. The inlet of the delivery pump 56 is communicated with the heating cavity 514; the heat exchange medium inside the heat exchange pipe 53 heats the water inside the heating cavity 514. The temperature sensor 57 is used to detect the water temperature inside the heating cavity 514. When the water temperature reaches the preset value, the controller controls the delivery pump 56 to work to deliver the water inside the heating cavity 514 to the evaporation cavity 512. When the liquid level sensor 58 detects that there is no liquid inside the heating cavity 514, the controller controls the delivery pump 56 to stop working, and at the same time controls the driving member 510 to work to move the baffle 511 to open the opening, so that the water inside the storage cavity 513 enters the heating cavity 514. After the water replenishment is completed, the driving member 510 drives the baffle 511 to reset to ensure that the water in contact with the heat exchange pipe 53 is not at a relatively high temperature, so that the heat of the heat exchange medium inside the heat exchange pipe 53 can be fully absorbed, and the heat of the heat exchange medium inside the heat exchange pipe 53 is reduced, so that the heat exchange medium inside the heat exchange pipe 53 can fully cool the exhaust gas to reduce the heat of the exhaust gas; the electric heating device 55 in the evaporation cavity 512 is used to heat the water inside the evaporation cavity 512 to evaporate it into steam to ensure that the heating device 5 will generate hot steam.

[0034] It should be noted that an electromagnetic valve is installed at the inlet of the delivery pump 56. When the delivery pump 56 is started, the electromagnetic valve will open to connect the evaporation chamber 512 with the heating chamber 514, so that the steam inside the heating chamber 514 can enter the interior of the evaporation chamber 512; and an air pressure sensor is installed in the inner cavity of the heating chamber 514 to detect the air pressure inside the heating chamber 514. When the liquid level sensor 58 detects that there is no water and the air pressure sensor detects that the air pressure is lower than a preset value, the controller will control the delivery pump 56 to stop working and control the driving member 510 to start.

[0035] Example 2

[0036] As a further optimized solution of Example 1, please refer to Figure 2 , Figure 3 and Figure 4 A sleeve 52 is sleeved on the outer wall of the heat exchange pipe 53, and an opening 5204 is opened on the outer surface of the sleeve 52. A fan blade 5205 is rotatably provided in the inner cavity of the sleeve 52. The fan blade 5205 is used to cool the heat exchange medium in the heat exchange pipe 53 passing through the working box 51, ensuring that the temperature of the heat exchange medium inside the heat exchange pipe 53 is reduced, so as to ensure that it can fully absorb the heat in the exhaust gas and significantly reduce the temperature of the exhaust gas.

[0037] In this embodiment, as a further optimized solution, please refer to Figure 4 An impeller 5201 is rotatably provided in the inner cavity of the heat exchange pipe 53, a transmission shaft 5202 is rotatably provided on the set 52, a gear is provided on the shaft of the impeller 5201, the gear is meshed with the transmission shaft 5202, and the transmission shaft 5202 and the shaft of the fan blade 5205 are transmitted through a conveyor belt 5203; when the heat exchange medium flows inside the heat exchange pipe 53, it will drive the impeller 5201 to rotate, and the transmission is transmitted through the transmission shaft 5202 and the conveyor belt 5203, so that the fan blade 5205 rotates, and the power of the flow of the heat exchange medium is used to drive the fan blade 5205 to rotate.

[0038] Example 3

[0039] As a further optimized solution of Example 1, please refer to Figure 1 A first solenoid valve 9 (three-way solenoid valve) is provided at the outlet of the filter 1, and the outlets of the first solenoid valve 9 are respectively connected to the turbine generator 6 and the heat exchanger 2, and the outlet of the turbine generator 6 is connected to the inlet of the heat exchanger 2; when analyzing the natural gas in the activated carbon, the controller controls the first solenoid valve 9 to change the airflow channel, so that the exhaust gas enters the turbine generator 6 for power generation, and then enters the storage tank 3 for storage, so as to reasonably utilize the exhaust gas power to avoid its direct waste, and the energy generated by power generation can be used to power the electrical equipment of the recovery device, thereby achieving the effect of saving energy.

[0040] Although embodiments of the present invention have been shown and described, those of ordinary skill in the art will appreciate that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Dual-fuel engine fuel recovery device, characterized in that: Comprising: A filter (1), a heat exchanger (2), a storage tank (3) and an adsorption tower (4) connected in sequence; The adsorption tower (4) is provided with a heating device (5) and a condenser (7), and a gas sensor (8) is provided at the discharge port of the adsorption tower (4); the adsorption tower (4) uses activated carbon to adsorb natural gas in the waste gas, and the heating device (5) is used to heat the activated carbon in the adsorption tower (4) with the waste gas heat recovered by the heat exchanger (2) when the gas sensor (8) detects an increase in the natural gas content in the discharged gas, so as to desorb the natural gas.

2. The fuel recovery device for a dual-fuel engine according to claim 1, characterized in that: The heating device (5) includes a working box (51) and a heat exchange pipe (53) provided on the working box (51), the heat exchange pipe (53) is connected to the heat exchanger (2), and a circulation pump (10) is provided on the heat exchange pipe (53).

3. The fuel recovery device for a dual-fuel engine according to claim 2, characterized in that: An electric heating device (55) and a temperature sensor (57) are provided in the working box (51).

4. The fuel recovery device for a dual-fuel engine according to claim 3, characterized in that: A first partition (54) is provided in the working box (51), and the first partition (54) is used to divide the inner cavity of the working box (51) into an evaporation cavity (512) and a working cavity. The heat exchange pipe (53) is provided in the working cavity. The evaporation cavity (512) is connected to the adsorption tower (4), the electric heating device (55) is provided in the evaporation cavity (512), and a delivery pump (56) is provided in the evaporation cavity (512) to deliver the liquid inside the working cavity to the evaporation cavity (512).

5. The fuel recovery device for a dual-fuel engine according to claim 4, characterized in that: A second partition (59) is provided in the working cavity, and the second partition (59) is used to divide the working cavity into a storage cavity (513) and a heating cavity (514). The storage cavity (513) and the heating cavity (514) are distributed vertically. An opening is provided on the second partition (59). The working box (51) is provided with a baffle (511) for blocking the opening and a driving member (510) for driving the baffle (511) to move. A liquid level sensor (58) is provided in the heating cavity (514), and the heat exchange pipe (53) and the temperature sensor (57) are both provided in the heating cavity (514). The storage cavity (513) is connected to the condenser (7).

6. The fuel recovery device for a dual-fuel engine according to claim 2, characterized in that: A kit (52) is sleeved on the outer wall of the heat exchange pipe (53), an opening (5204) is provided on the kit (52), and a fan blade (5205) is rotatably provided in the kit (52). The fan blade (5205) is used to cool the heat exchange medium passing through the working box (51) in the heat exchange pipe (53).

7. The fuel recovery device for a dual-fuel engine according to claim 6, characterized in that: An impeller (5201) is provided in the heat exchange pipe (53), a transmission shaft (5202) is rotatably provided on the kit (52), a gear for meshing with the transmission shaft (5202) is provided on the shaft of the impeller (5201), and the transmission shaft (5202) and the shaft of the fan blade (5205) are driven by a conveyor belt (5203).

8. The fuel recovery device for a dual-fuel engine according to claim 1, characterized in that: A first electromagnetic valve (9) is provided at the outlet of the filter (1), and the outlet of the first electromagnetic valve (9) is respectively connected to a turbine generator (6) and a heat exchanger (2). The air outlet of the turbine generator (6) is connected to the inlet of the heat exchanger (2).

9. Method for fuel recovery of a dual-fuel engine, using the dual-fuel engine fuel recovery device according to any one of claims 1-8, characterized in that: Including the following steps: S1: The exhaust gas discharged from the dual-fuel engine is filtered by the filter (1), then enters the heat exchanger (2) to be cooled, and then enters the adsorption tower (4) through the storage tank (3), and is discharged after the natural gas is adsorbed by the activated carbon; S2: When the gas sensor (8) detects an increase in the natural gas content in the gas discharged from the adsorption tower (4), the storage tank (3) stops delivering the exhaust gas to the adsorption tower (4). At the same time, the heating device (5) uses the waste gas heat recovered by the heat exchanger (2) to heat water, and the generated steam is introduced into the adsorption tower (4) to desorb the natural gas from the activated carbon. The desorbed gas is condensed by the condenser (7) to separate the steam from the natural gas, and the natural gas is recovered.

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