Steam condensate water recycling system for drying cylinder of paper machine

Abstract

The utility model belongs to the technical field of papermaking machinery, and particularly relates to a paper machine drying cylinder steam condensate recycling system which comprises a feeding unit, a conveying unit, a collecting unit and a discharging unit, a first flash evaporation piece flows into a second steam-water separator, the second flash evaporation piece and a third flash evaporation piece enable liquid to flow into the first steam-water separator, and the third flash evaporation piece flows into the second steam-water separator. Liquid in the first steam-water separator is recycled to the second drying cylinder on the first steam group through depressurization flash evaporation by the first steam-water separator, condensed water is conveyed to the second steam-water separator for further flash evaporation after flash evaporation, and generated flash evaporation is used for preheating flash steam of the gas hood heater; the condensate water after flash evaporation is sent to the condensate water preheater of the gas hood heater through the condensate water pump for heat exchange and sent back to a power plant for reuse, and compared with the prior art, the flash steam recycling rate is increased and the steam consumption is reduced by additionally arranging one group of first flash evaporation pieces, two groups of second flash evaporation pieces and three groups of third flash evaporation pieces.

Description

Technical Field

[0001] The utility model relates to the technical field of papermaking machinery, and more specifically, it relates to a steam condensate recovery and utilization system for a paper machine dryer cylinder. Background Art

[0002] In recent years, as the contradiction of energy shortage has become increasingly prominent and the proportion of energy consumption in production costs has become larger and larger, the energy consumption of the dryer section of the paper machine in the papermaking industry accounts for 45 - 55% of the energy consumption in the entire papermaking process. To some extent, the amount of steam consumption has become a key factor directly affecting the profits and competitiveness of papermaking enterprises. Therefore, it is imperative to optimize the paper machine steam system and reduce steam energy consumption.

[0003] For example, a paper machine dryer cylinder condensate treatment system disclosed in the authorized announcement number CN203559304U. One end of the siphon pipe of this system is connected to the dryer cylinder through a steam pipe, the other end of the siphon pipe is connected with a steam trap, the steam trap is connected with a cooling and collection tank, a cooling water pipe is connected to the cooling and collection tank, and a water pump is connected to the cooling and collection tank.

[0004] In the above, it does not fully recover and utilize the condensate of the dryer cylinder. When the pressure of the low-temperature cylinder dryer cylinder is high, there will be problems such as poor drainage of the dryer cylinder, low recovery rate of flash steam, and poor discharge of non-condensable gases, resulting in a large steam consumption. Summary of the Utility Model

[0005] Aiming at the deficiencies of the existing technology, the purpose of the utility model is to provide a steam condensate recovery and utilization system for a paper machine dryer cylinder that can improve the recovery rate of flash steam and reduce steam consumption.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A steam condensate recovery and utilization system for a paper machine dryer cylinder, characterized in that

[0008] it includes a feeding unit, a transmission unit, a collection unit, and a discharging unit. Both ends of the transmission unit are electrically connected to one end of the feeding unit and the collection unit respectively, the other end of the collection unit is electrically connected to the discharging unit. The feeding unit includes a feed port for facilitating the entry of liquid and a first liquid inlet group connected to the feed port. A surface condenser is provided on the first liquid inlet group. The transmission unit includes a first steam group and a flash evaporation assembly. Both the first steam group and the flash evaporation assembly are electrically connected to the surface condenser. The collection unit includes a first steam-water separator and a second steam-water separator. The first steam-water separator and the second steam-water separator are electrically connected. The first steam-water separator and the flash evaporation assembly are electrically connected. The second steam-water separator is electrically connected to the first steam group. The discharging unit includes a second steam group and a power plant for facilitating the recovery of the flash-evaporated condensate. The second steam group is electrically connected to the second steam-water separator.

[0009] The utility model is further arranged as follows: the flash evaporation assembly includes a first flash evaporation member with one set, a second flash evaporation member with two sets, and a third flash evaporation member with three sets. A control part and a first drying cylinder are arranged on each of the first flash evaporation member, the second flash evaporation member, and the third flash evaporation member. The control part is electrically connected to the first drying cylinder so that the liquid in the first flash evaporation member flows to the second steam-water separator, and the second flash evaporation member and the third flash evaporation member flow into the first steam-water separator.

[0010] The utility model is further arranged as follows: a pressure indication control, a differential pressure indicator, and a pressure transmitter are arranged on the control part. The pressure indication control, the differential pressure indicator, and the pressure transmitter are all electrically connected. A manual switch is arranged on the third flash evaporation member.

[0011] The utility model is further arranged as follows: a second drying cylinder is arranged on the first steam group. Both ends of the second drying cylinder are electrically connected to the first steam-water separator and the second steam-water separator.

[0012] The utility model is further arranged as follows: the feeding unit further includes a second liquid inlet group. A third drying cylinder is arranged between the first liquid inlet group and the second liquid inlet group. The first liquid inlet group and the second liquid inlet group are both electrically connected to the third drying cylinder. A fourth drying cylinder connected to the third drying cylinder is arranged on the second steam group.

[0013] The utility model is further arranged as follows: temperature control zones, condensate pumps, and liquid controllers are arranged on each of the first drying cylinder, the second drying cylinder, and the fourth drying cylinder. The temperature control zones, the condensate pumps, and the liquid controllers are all electrically connected.

[0014] The utility model is further arranged as follows: two condensate pumps are arranged on each of the first steam-water separator and the second steam-water separator. An air hood heater is arranged between the second steam-water separator and the second steam group.

[0015] By adopting the above technical solution, the beneficial effects of the utility model are as follows:

[0016] The liquid in the first flash evaporation member flows into the second steam-water separator. The second flash evaporation member and the third flash evaporation member flow the liquid into the first steam-water separator. For the liquid placed in the first steam-water separator, the first steam-water separator is recycled to the second drying cylinder on the first steam group through pressure-reducing flash evaporation. The flash evaporation condensate is sent to the second steam-water separator for further flash evaporation. The generated flash steam is used for preheating the flash steam of the air hood heater. The flash evaporation condensate is sent to the condensate preheater of the air hood heater through a condensate pump for heat exchange. The temperature of the heat-exchanged condensate can reach 85°C and is sent back to the power plant for reuse. By adding one set of the first flash evaporation member, two sets of the second flash evaporation member, and three sets of the third flash evaporation member, the recovery utilization rate of the flash steam is improved and the steam consumption is reduced. Description of the Drawings

[0017] Figure 1It is a schematic flow diagram of an embodiment of the present utility model.

[0018] Feed inlet 1, first liquid inlet group 2, surface condenser 3, first steam group 4, flash evaporation assembly 5, first flash evaporation part 6, second flash evaporation part 7, third flash evaporation part 8, first steam-water separator 9, second steam-water separator 10, second steam group 11, power plant return 12, control unit 13, first drying cylinder 14, second drying cylinder 15, second liquid inlet group 16, third drying cylinder 17, fourth drying cylinder 18, hood heater 19. Detailed implementation manner

[0019] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present utility model.

[0020] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0021] As Figure 1 shown, the paper machine drying cylinder steam condensate recovery and utilization system includes a feeding unit, a transmission unit, a collection unit, and a discharging unit. The two ends of the transmission unit are electrically connected to the feeding unit and one end of the collection unit respectively, and the other end of the collection unit is electrically connected to the discharging unit.

[0022] The feeding unit includes a feed inlet 1 for facilitating the entry of liquid, a hot water tank for discharging hot water, and a first liquid inlet group 2 connected to the feed inlet 1. A surface condenser 3 is provided on the first liquid inlet group 2. The feeding unit further includes a second liquid inlet group 16. The second liquid inlet group 16 is provided with a water inlet and a return port. A vacuum generator is provided inside the second liquid inlet group 16. A third drying cylinder 17 is provided between the first liquid inlet group 2 and the second liquid inlet group 16. Both the first liquid inlet group 2 and the second liquid inlet group 16 are electrically connected to the third drying cylinder 17.

[0023] The transmission unit includes a first steam group 4 and a flash evaporation assembly 5. Both the first steam group 4 and the flash evaporation assembly 5 are electrically connected to the surface condenser 3. The collection unit includes a first steam-water separator 9 and a second steam-water separator 10. The first steam-water separator 9 and the second steam-water separator 10 are electrically connected. The first steam-water separator 9 and the flash evaporation assembly 5 are electrically connected. The second steam-water separator 10 is electrically connected to the first steam group 4. The blanking unit includes a second steam group and a power plant 12 for facilitating the recovery of the condensed water after flash evaporation. The second steam group is electrically connected to the second steam-water separator 10.

[0024] The second steam group is provided with a fourth drying cylinder 18 connected to the third drying cylinder 17. A part of the liquid enters through the upper water hole, flows to the fourth drying cylinder 18 through the third drying cylinder 17, and is finally recovered to the power plant 12. Another part of the liquid enters from the feed port 1, flows to the third drying cylinder 17 through the surface condenser 3, and is finally recovered to the power plant 12 through the third drying cylinder 17 and the fourth drying cylinder 18 in sequence.

[0025] The flash evaporation assembly 5 includes a first flash evaporation part 6 with one group, a second flash evaporation part 7 with two groups, and a third flash evaporation part 8 with three groups. A control part and a first drying cylinder 14 are provided on each of the first flash evaporation part 6, the second flash evaporation part 7, and the third flash evaporation part 8. The control part and the first drying cylinder 14 are electrically connected, so that the liquid in the first flash evaporation part 6 flows to the second steam-water separator 10, and the second flash evaporation part 7 and the third flash evaporation part 8 flow into the first steam-water separator 9.

[0026] The control part is provided with a pressure indication control, a differential pressure indicator, and a pressure transmitter. The pressure indication control, the differential pressure indicator, and the pressure transmitter are all electrically connected. A manual switch is provided on the third flash evaporation part 8.

[0027] The first steam group 4 is provided with a second drying cylinder 15. Both ends of the second drying cylinder 15 are electrically connected to the first steam-water separator 9 and the second steam-water separator 10.

[0028] Temperature control zones, condensate pumps, and liquid controllers are provided on each of the first drying cylinder 14, the second drying cylinder 15, and the fourth drying cylinder 18. The temperature control zones, the condensate pumps, and the liquid controllers are all electrically connected.

[0029] The present utility model is further configured such that: two condensate pumps are provided on each of the first steam-water separator 9 and the second steam-water separator 10, and an air hood heater 19 is provided between the second steam-water separator 10 and the second steam group.

[0030] Working principle: The first flash evaporation part 6 flows into the second steam-water separator 10. The second flash evaporation part 7 and the third flash evaporation part 8 flow the liquid into the first steam-water separator 9. For the liquid placed in the first steam-water separator 9, the first steam-water separator 9 is recycled to the second drying cylinder 15 on the first steam group 4 through pressure-reducing flash evaporation. The condensed water after flash evaporation is sent to the second steam-water separator 10 for further flash evaporation. The generated flash steam is used for preheating the flash steam of the hood heater 19. The condensed water after flash evaporation is sent to the condensate preheater of the hood heater 19 through a condensate pump for heat exchange. The temperature of the heat-exchanged condensed water can reach 85°C and is sent back to the power plant 12 for reuse. By adding one group of the first flash evaporation part 6, two groups of the second flash evaporation part 7 and three groups of the third flash evaporation part 8, the recovery utilization rate of the flash steam is improved and the steam consumption is reduced.

[0031] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A steam condensate recovery and utilization system for a paper machine dryer, characterized in that it includes a feeding unit, a transmission unit, a collection unit and a discharging unit, both ends of the transmission unit are electrically connected to the feeding unit and one end of the collection unit respectively, the other end of the collection unit is electrically connected to the discharging unit, the feeding unit includes a feed port (1) for facilitating the entry of liquid and a first liquid inlet group (2) connected to the feed port (1), a surface condenser (3) is provided on the first liquid inlet group (2), the transmission unit includes a first steam group (4) and a flash evaporation component (5), both the first steam group (4) and the flash evaporation component (5) are electrically connected to the surface condenser (3), the collection unit includes a first steam-water separator (9) and a second steam-water separator (10), and the first steam-water separator (9) and the second steam-water separator (10) are electrically connected, the first steam-water separator (9) is electrically connected to the flash evaporation component (5), the second steam-water separator (10) is electrically connected to the first steam group (4), the discharging unit includes a second steam group and a power plant return (12) for facilitating the recovery of the flashed condensate, and the second steam group is electrically connected to the second steam-water separator (10).

2. The steam condensate recovery and utilization system for a paper machine drying cylinder according to claim 1, wherein, The flash evaporation component (5) includes a first flash evaporation part (6) with one group, a second flash evaporation part (7) with two groups and a third flash evaporation part (8) with three groups. A control part and a first dryer (14) are provided on the first flash evaporation part (6), the second flash evaporation part (7) and the third flash evaporation part (8). The control part and the first dryer (14) are electrically connected so that the liquid in the first flash evaporation part (6) flows to the second steam-water separator (10), and the second flash evaporation part (7) and the third flash evaporation part (8) flow into the first steam-water separator (9).

3. A steam condensate recovery and utilization system for a paper machine drying cylinder according to claim 2, characterized in that, A pressure indication control, a differential pressure indicator and a pressure transmitter are provided on the control part, and the pressure indication control, the differential pressure indicator and the pressure transmitter are all electrically connected. A manual switch is provided on the third flash evaporation part (8).

4. A steam condensate recovery and utilization system for a paper machine dryer cylinder according to claim 2, characterized in that, A second dryer (15) is provided on the first steam group (4), and both ends of the second dryer (15) are electrically connected to the first steam-water separator (9) and the second steam-water separator (10).

5. The steam condensate recovery and utilization system for a paper machine drying cylinder according to claim 1, wherein, The feeding unit further includes a second liquid inlet group (16). A third dryer (17) is provided between the first liquid inlet group (2) and the second liquid inlet group (16). Both the first liquid inlet group (2) and the second liquid inlet group (16) are electrically connected to the third dryer (17). A fourth dryer (18) connected to the third dryer (17) is provided on the second steam group.

6. The steam condensate recovery and utilization system for a paper machine dryer cylinder according to claim 2, characterized in that, Temperature control zones, condensate pumps and liquid controllers are provided on the first dryer (14), the second dryer (15) and the fourth dryer (18), and the temperature control zones, the condensate pumps and the liquid controllers are all electrically connected.

7. A steam condensate recovery and utilization system for a paper machine drying cylinder according to claim 1, characterized in that, Two condensate pumps are provided on both the first steam-water separator (9) and the second steam-water separator (10). An air hood heater (19) is provided between the second steam-water separator (10) and the second steam group.

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