Material drying system and method

Abstract

The present invention relates to a material drying system and method. The material drying system includes a drying dehumidification regeneration unit. The drying dehumidification regeneration unit includes a drying system for drying wet materials using dry air, a dehumidification system for dehumidifying wet air using a working fluid, and an MVR regeneration system for evaporating and concentrating the working fluid. The drying system is connected to the dehumidification system via a pipeline, and the dehumidification system is connected to the MVR regeneration system via a pipeline. The material drying method includes a drying step for drying wet materials using dry air, a dehumidification step for dehumidifying wet air using a working fluid, and an MVR regeneration step for evaporating and concentrating the working fluid. The present invention dries wet materials using dry air, dehumidifies wet air using a working fluid, and concentrates and regenerates the working fluid using an MVR system, and recovers the sensible heat of the dried materials via a heat recovery system, thereby reducing the energy consumption of material drying and alleviating environmental pollution.

Description

Technical Field

[0001] The present invention relates to a material drying system and method, in particular to a material drying system and method through solution dehumidification drying MVR regeneration, belonging to the technical field of energy conservation and environmental protection. Background Art

[0002] Material drying involves many industries. Drying operations often become the main energy-consuming part of the production process. The environmental pollution of drying units is often quite serious. Therefore, energy saving and consumption reduction and clean production have also become important goals of drying industry technology. The current drying process mainly uses fossil energy combustion to provide external heat sources such as hot air, steam, and flue gas to heat the drying materials or uses reverse Carnot cycle heat pump condensation or its extended transformation technology to dehumidify the drying materials. The energy consumption and operating costs are high, and remote monitoring and management are inconvenient. At the same time, it is accompanied by waste gas or greenhouse gas emissions that bring environmental problems. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention aims to provide a material drying system and method with low energy consumption and operating costs, convenient remote monitoring and management, and no environmental pollution and greenhouse gas emissions.

[0004] A material drying system of the present invention comprises a drying and dehumidifying regeneration unit, wherein the drying and dehumidifying regeneration unit comprises a drying system for drying wet materials by using dry air, a dehumidifying system for dehumidifying wet air by using a working fluid, and an MVR regeneration system for evaporating and concentrating the working fluid; the drying system is connected to the dehumidifying system by a pipeline, and the dehumidifying system is connected to the MVR regeneration system by a pipeline.

[0005] The above-mentioned drying system includes a feed hopper, a loader, a material distributor, a dryer, a discharge hopper, a circulating fan and an air inlet pipe; the feed hopper is connected to the material distributor through the loader; the material distributor is connected to the dryer; the circulating fan is connected to the dryer through the air inlet pipe; and the discharge hopper is connected to the dryer.

[0006] The dehumidification system comprises a return air duct, a dehumidifier, a defogger and a dehumidification circulation pump; the dryer of the drying system is connected to the dehumidifier through the return air duct; the defogger is connected to the dehumidifier; the inlet and outlet of the dehumidification circulation pump are connected to the dehumidifier through a pipeline.

[0007] The above-mentioned MVR regeneration system includes a working liquid discharge pump, a heat exchanger, an MVR compressor, a separator, an evaporative demister, an evaporative circulation pump and a regeneration liquid return pipe; the inlet and outlet of the working liquid discharge pump are respectively connected to the dehumidifier and the inlet of the heat exchanger of the dehumidification system through pipelines; the outlet of the heat exchanger is connected to the separator through a pipeline; the evaporative demister is connected to the separator; the inlet and outlet of the MVR compressor are respectively connected to the separator outlet and the heat exchanger inlet through pipelines; the inlet and outlet of the evaporative circulation pump are respectively connected to the separator outlet and the heat exchanger inlet through pipelines; the regeneration liquid return pipe is connected to the evaporative circulation pump outlet and the dehumidification circulation pump inlet of the dehumidification system.

[0008] The present invention also includes a heat recovery unit, which includes a heat exchange circulation pump and a heat exchange pipe; the material distributor of the drying system is connected to the discharge hopper of the drying system through the heat exchange pipe and the heat exchange circulation pump.

[0009] The present invention also comprises an electrical control unit, which is an automatic control cabinet with a PLC program control and a remote communication module.

[0010] The material drying method of the present invention comprises a drying step of drying the wet material with dry air, a dehumidification step of dehumidifying the wet air with a working fluid, and an MVR regeneration step of evaporating and concentrating the working fluid.

[0011] The specific method of the above drying step is:

[0012] Step (A1): evenly distributing the wet material in the feed hopper onto the dryer through a feeder and a material distributor;

[0013] Step (A2): The dry hot air passes through the circulating fan and the air inlet pipe into the dryer to exchange heat with the wet material for evaporation;

[0014] Step (A3): The dry material is discharged from the dryer through the discharge hopper.

[0015] The specific method of the above dehumidification step is:

[0016] Step (B1): the wet air after the drying material absorbs moisture enters the dehumidifier through the return air duct;

[0017] Step (B2): the dehumidification circulation pump lifts the spraying working fluid to exchange heat and mass with the wet air;

[0018] Step (B3): The dehumidified air enters the return air duct after the water mist is captured by the demister.

[0019] The specific method of the above MVR regeneration step is:

[0020] Step (C1): the working fluid in the dehumidifier of the dehumidification system is mixed with the regeneration fluid at the outlet of the working fluid discharge pump and the evaporation circulation pump and enters the heat exchanger for heat exchange;

[0021] Step (C2): the mixed liquid heated by the heat exchanger enters the separator for evaporation and concentration;

[0022] Step (C3): the secondary steam generated by evaporation is separated into vapor and liquid by the evaporative demister and then enters the MVR compressor for compression and temperature increase;

[0023] Step (C4): The compressed and heated steam enters the heat exchanger to exchange heat with the working fluid and is condensed into liquid water and discharged;

[0024] Step (C5): The regeneration liquid in the separator is transported into the heat exchanger for circulation heating via the evaporation circulation pump, and part of the regeneration liquid enters the liquid inlet of the dehumidification circulation pump of the dehumidification system through the regeneration liquid return pipe to replenish the dehumidification working liquid.

[0025] The beneficial effects of the present invention are as follows: (1) The drying, dehumidification and regeneration process system and method provided by the present invention can reduce the regeneration energy consumption of the working fluid in the prior art, recover the sensible heat of the dry heat material, and further reduce the operating cost of the prior art drying process; (2) The automatic control cabinet with a remote communication module provided by the system of the present invention can solve the problem of inconvenient remote monitoring and management of the prior art drying system; (3) The drying, dehumidification and MVR regeneration process provided by the present invention can solve the environmental problems caused by the exhaust gas or greenhouse gas emissions in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the structure of the system of the present invention.

[0027] In the figure: 1. feeder, 2. material distributor, 3. dryer, 4. return air duct, 5. demister, 6. control cabinet, 7. MVR compressor, 8. condensing heat exchanger, 9. evaporative demister, 10. feed hopper, 11. heat exchange circulation pump, 12. heat exchange pipe, 13. air inlet pipe, 14. discharge hopper, 15. circulation fan, 16. dehumidifier, 17. dehumidification circulation pump, 18. working fluid discharge pump, 19. regeneration liquid return pipe, 20. evaporative circulation pump, 21. separator. DETAILED DESCRIPTION

[0028] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods.

[0029] like Figure 1 As shown, a material drying system of the present invention includes a drying and dehumidification regeneration unit, a heat recovery unit and an electrical control unit.

[0030] The drying and dehumidification regeneration unit includes a drying system for drying wet materials using dry air, a dehumidification system for dehumidifying wet air using a working fluid, and an MVR regeneration system for evaporating and concentrating the working fluid; the drying system is connected to the dehumidification system through a pipeline, and the dehumidification system is connected to the MVR regeneration system through a pipeline.

[0031] The drying system includes a feed hopper 10, a loader 1, a material distributor 2, a dryer 3, a discharge hopper 14, a circulating fan 15 and an air inlet pipe 13; the feed hopper 10 is connected to the material distributor 2 through the loader 1; the material distributor 2 is connected to the dryer 3; the circulating fan 15 is connected to the dryer 3 through the air inlet pipe 13; the discharge hopper 14 is connected to the dryer 3.

[0032] The dehumidification system includes a return air duct 4, a dehumidifier 16, a defogger 5 and a dehumidification circulation pump 17; the dryer 3 of the drying system is connected to the dehumidifier 16 through the return air duct 4; the defogger 5 is connected to the dehumidifier 16; the inlet and outlet of the dehumidification circulation pump 17 are connected to the dehumidifier 16 through a pipeline.

[0033] The MVR regeneration system includes a working liquid discharge pump 18, a heat exchanger 8, an MVR compressor 7, a separator 21, an evaporative demister 9, an evaporative circulation pump 20 and a regeneration liquid return pipe 19; the inlet and outlet of the working liquid discharge pump 18 are respectively connected to the dehumidifier 16 and the inlet of the heat exchanger 8 of the dehumidification system through pipelines; the outlet of the heat exchanger 8 is connected to the separator 21 through a pipeline; the evaporative demister 9 is connected to the separator 21; the inlet and outlet of the MVR compressor 7 are respectively connected to the air outlet of the separator 21 and the air inlet of the heat exchanger 8 through pipelines; the inlet and outlet of the evaporative circulation pump 20 are respectively connected to the discharge port of the separator 21 and the inlet of the heat exchanger 8 through pipelines; the regeneration liquid return pipe 19 is connected to the outlet of the evaporative circulation pump 20 and the inlet of the dehumidification circulation pump 17 of the dehumidification system.

[0034] The heat recovery unit includes a heat exchange circulation pump 11 and a heat exchange pipe 12; the material distributor 2 of the drying system is connected to the discharge hopper 14 of the drying system through the heat exchange pipe 12 and the heat exchange circulation pump 11.

[0035] The electrical control unit is an automatic control cabinet 6 with a PLC program control and remote communication module; the loader 1, the material distributor 2, the dryer 3, the heat exchange circulation pump 11, the circulation fan 15, the dehumidification circulation pump 17, the working fluid discharge pump 18, the MVR compressor 7 and the evaporation circulation pump 20 are electrically connected to the automatic control cabinet 6 respectively.

[0036] The implementation steps of the material drying system of the present invention include a drying step of drying the wet material with dry air, a dehumidification step of dehumidifying the wet air with a working fluid, and an MVR regeneration step of evaporating and concentrating the working fluid. The drying steps are specifically:

[0037] Step (A1): the wet material in the feed hopper 10 is evenly distributed on the dryer 3 through the feeder 1 and the material distributor 2;

[0038] Step (A2): The dry hot air passes through the circulating fan 15 and the air inlet pipe 13 into the dryer 3 to exchange heat with the wet material for evaporation;

[0039] Step (A3): The dry material is discharged from the dryer 3 through the discharge hopper 14.

[0040] The dehumidification steps are as follows:

[0041] Step (B1): the wet air after the drying material absorbs moisture enters the dehumidifier 16 through the return air duct 4;

[0042] Step (B2): the dehumidification circulation pump 17 lifts the spraying working fluid to exchange heat and mass with the wet air;

[0043] Step (B3): The dehumidified air enters the return air duct 4 after the water mist is captured by the demister 5 .

[0044] The specific steps of MVR regeneration are:

[0045] Step (C1): the working fluid in the dehumidifier 16 of the dehumidification system is mixed with the regeneration fluid at the outlet of the evaporation circulation pump 20 through the working fluid discharge pump 18 and enters the heat exchanger 8 for heat exchange;

[0046] Step (C2): the mixed liquid heated by the heat exchanger 8 enters the separator 21 for evaporation and concentration;

[0047] Step (C3): the secondary steam generated by evaporation is separated into vapor and liquid by the evaporation demister 9 and then enters the MVR compressor 7 for compression and temperature increase;

[0048] Step (C4): The compressed and heated steam enters the heat exchanger 8 to exchange heat with the working fluid and is condensed into liquid water and discharged;

[0049] Step (C5): The regeneration liquid in the separator 21 is transported into the heat exchanger 8 for cyclic heating via the evaporation circulation pump 20, and part of the regeneration liquid enters the liquid inlet of the dehumidification circulation pump 17 of the dehumidification system via the regeneration liquid return pipe 19 to replenish the dehumidification working liquid.

[0050] The present invention utilizes dry air to dry wet materials, dehumidifies wet air through working fluid, and concentrates and regenerates the working fluid through an MVR system, and recovers sensible heat of the dry materials through a heat recovery system, thereby reducing energy consumption for material drying and alleviating environmental pollution.

[0051] The heat recovery implementation steps of the material drying system of the present invention; the dry hot material in the discharge hopper 14 is circulated and transported through the circulating water in the heat exchange pipe 12 through the heat exchange circulation pump 11 to exchange heat with the wet material in the material distributor 2 to recover the sensible heat of the dry hot material.

[0052] The automatic control and remote communication implementation steps of the material drying system of the present invention are as follows: the feeder 1, the material distributor 2, the dryer 3, the heat exchange circulation pump 11, the circulation fan 15, the dehumidification circulation pump 17, the working liquid discharge pump 18, the MVR compressor 7 and the evaporation circulation pump 20 are electrically connected to the automatic control cabinet 6 respectively; the automatic control cabinet 6 supplies power to the feeder 1, the material distributor 2, the dryer 3, the heat exchange circulation pump 11, the circulation fan 15, the dehumidification circulation pump 17, the working liquid discharge pump 18, the MVR compressor 7 and the evaporation circulation pump 20 and coordinates the smooth operation of each device according to the set program, and at the same time transmits the system operation status and fault signals to the outside through the built-in functional module for remote monitoring and management.

[0053] The above description is only a preferred feasible implementation scheme of the present invention and is not intended to limit the patent scope of the present invention. Therefore, all method steps and equivalent changes made using the contents of this specification and the drawings are within the protection scope of the present invention.

Claims

1. A material drying system, characterized in that: It includes a drying and dehumidification regeneration unit, which includes a drying system for drying wet materials with dry air, a dehumidification system for dehumidifying wet air with a working fluid, and an MVR regeneration system for evaporating and concentrating the working fluid; the drying system is connected to the dehumidification system through a pipeline, and the dehumidification system is connected to the MVR regeneration system through a pipeline; The drying system comprises a feed hopper (10), a feeder (1), a material distributor (2), a dryer (3), a discharge hopper (14), a circulation fan (15) and an air inlet pipe (13); the feed hopper (10) is connected to the material distributor (2) via the feeder (1); the material distributor (2) is connected to the dryer (3); the circulation fan (15) is connected to the dryer (3) via the air inlet pipe (13); the discharge hopper (14) is connected to the dryer (3); The dehumidification system comprises a return air duct (4), a dehumidifier (16), a demister (5) and a dehumidification circulation pump (17); the dryer (3) of the drying system is connected to the dehumidifier (16) via the return air duct (4); the demister (5) is connected to the dehumidifier (16); the inlet and outlet of the dehumidification circulation pump (17) are connected to the dehumidifier (16) via a pipeline; The MVR regeneration system comprises a working liquid discharge pump (18), a heat exchanger (8), an MVR compressor (7), a separator (21), an evaporative demister (9), an evaporative circulation pump (20) and a regeneration liquid return pipe (19); the inlet and outlet of the working liquid discharge pump (18) are respectively connected to the dehumidifier (16) and the inlet of the heat exchanger (8) of the dehumidification system through pipelines; the outlet of the heat exchanger (8) is connected to the separator (21) through a pipeline; the evaporative demister (9) is connected to the separator (21); the inlet and outlet of the MVR compressor (7) are respectively connected to the air outlet of the separator (21) and the air inlet of the heat exchanger (8) through pipelines; the inlet and outlet of the evaporative circulation pump (20) are respectively connected to the discharge port of the separator (21) and the inlet of the heat exchanger (8) through pipelines; the regeneration liquid return pipe (19) is connected to the outlet of the evaporative circulation pump (20) and the inlet of the dehumidification circulation pump (17) of the dehumidification system; It also includes a heat recovery unit, which includes a heat exchange circulation pump (11) and a heat exchange pipe (12); the material distributor (2) of the drying system is connected to the discharge hopper (14) of the drying system through the heat exchange pipe (12) and the heat exchange circulation pump (11); It also includes an electrical control unit, which is an automatic control cabinet (6) with a PLC program control and remote communication module.

2. A material drying method, characterized in that: The material drying system comprises a drying and dehumidifying regeneration unit, wherein the drying and dehumidifying regeneration unit comprises a drying system for drying wet materials using dry air, a dehumidifying system for dehumidifying wet air using a working fluid, and an MVR regeneration system for evaporating and concentrating the working fluid; the drying system is connected to the dehumidifying system via a pipeline, and the dehumidifying system is connected to the MVR regeneration system via a pipeline; the drying system comprises a feed hopper (10), a feeder (1), a material distributor (2), a dryer (3), a discharge hopper (14), a circulation The fan (15) and the air inlet pipe (13) are connected; the feed hopper (10) is connected to the material distributor (2) through the feeder (1); the material distributor (2) is connected to the dryer (3); the circulating fan (15) is connected to the dryer (3) through the air inlet pipe (13); the discharge hopper (14) is connected to the dryer (3); the dehumidification system comprises a return air pipe (4), a dehumidifier (16), a demister (5) and a dehumidification circulation pump (17); the dryer (3) of the drying system is connected to the dehumidifier (16) through the return air pipe (4). (16); the demister (5) is connected to the dehumidifier (16); the inlet and outlet of the dehumidification circulation pump (17) are connected to the dehumidifier (16) through a pipeline; the MVR regeneration system includes a working liquid discharge pump (18), a heat exchanger (8), an MVR compressor (7), a separator (21), an evaporative demister (9), an evaporative circulation pump (20) and a regeneration liquid return pipe (19); the inlet and outlet of the working liquid discharge pump (18) are respectively connected to the dehumidifier (16) and the inlet of the heat exchanger (8) of the dehumidification system through pipelines The outlet of the heat exchanger (8) is connected to the separator (21) through a pipeline; the evaporative demister (9) is connected to the separator (21); the inlet and outlet of the MVR compressor (7) are respectively connected to the air outlet of the separator (21) and the air inlet of the heat exchanger (8) through pipelines; the inlet and outlet of the evaporative circulation pump (20) are respectively connected to the discharge port of the separator (21) and the inlet of the heat exchanger (8) through pipelines; the regeneration liquid return pipe (19) is connected to the outlet of the evaporative circulation pump (20) and the inlet of the dehumidification circulation pump (17) of the dehumidification system; The material drying method of the material drying system comprises the following steps: a drying step of drying the wet material by using dry air, a dehumidification step of dehumidifying the wet air by using a working fluid, and an MVR regeneration step of evaporating and concentrating the working fluid; The specific method of the drying step is as follows: Step (A1): the wet material in the feed hopper (10) is evenly distributed on the dryer (3) through the feeder (1) and the material distributor (2); Step (A2): the dry hot air enters the dryer (3) through the circulating fan (15) and the air inlet pipe (13) to exchange heat with the wet material for evaporation; Step (A3): the dry material is discharged from the dryer (3) through the discharge hopper (14); The specific method of the dehumidification step is as follows: Step (B1): the wet air after the drying material absorbs moisture enters the dehumidifier (16) through the return air duct (4); Step (B2): the dehumidification circulation pump (17) lifts the spraying working fluid to exchange heat and mass with the wet air; Step (B3): the dehumidified air enters the return air duct (4) after the water mist is captured by the demister (5); The specific method of the MVR regeneration step is as follows: Step (C1): the working fluid in the dehumidifier (16) of the dehumidification system is mixed with the regeneration fluid at the outlet of the evaporation circulation pump (20) through the working fluid discharge pump (18) and enters the heat exchanger (8) for heat exchange; Step (C2): the mixed fluid heated by the heat exchanger (8) enters the separator (21) for evaporation and concentration; Step (C3): the secondary steam generated by evaporation is separated into vapor and liquid by the evaporation demister (9) and enters the MVR compressor (7) for compression and temperature increase; Step (C4): the compressed and heated steam enters the heat exchanger (8) for heat exchange with the working fluid and condenses into liquid water for discharge; Step (C5): the regeneration fluid in the separator (21) is transported by the evaporation circulation pump (20) into the heat exchanger (8) for circulation and heating, and part of the regeneration fluid enters the liquid inlet of the dehumidification circulation pump (17) of the dehumidification system through the regeneration fluid return pipe (19) to replenish the dehumidification working fluid.

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