Optimization system for recycling and reusing condensation water

Abstract

The utility model belongs to the technical field of coking waste heat utilization, and particularly relates to an optimization system for recycling and reusing condensed water, which is characterized in that a steam inlet of a riser pump station deaerator is communicated with a steam port of a flash tank, a water inlet of the riser pump station deaerator is communicated with a medium outlet of a water-water heat exchanger, and a water outlet of the flash tank is communicated with a medium outlet of a water-water heat exchanger. A water outlet of the flash tank is communicated with an inner pipe inlet of the water-water heat exchanger, an inner pipe outlet of the water-water heat exchanger is communicated with a flue gas waste heat boiler demineralized water tank, and a medium inlet of the water-water heat exchanger is communicated with an ascending pipe pump station demineralized water tank through an ascending pipe pump station deoxygenated water pump; and a steam inlet of the flash tank is connected with a 0.6 MPa saturated high-temperature condensed water pipe. The device has the beneficial effects that the condensed water in a factory is directly recovered by utilizing the backpressure of the condensed water, the investment and the occupied area are saved, the heat of the high-temperature condensed water can be recovered, the consumption of circulating cooling water is saved, and the energy utilization rate of coking enterprises is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of coking waste heat utilization, and particularly relates to an optimized system for condensate recovery and reuse. Background Art

[0002] In coking projects, a condensate recovery station is usually set up to recover the whole-plant condensate. The saturated high-temperature condensate of about 0.6 MPa in the chemical unit is cooled by exchanging heat with circulating cooling water. The cooled condensate and other low-temperature condensate in the plant enter the condensate separation tank in the station, and then the condensate pump is used to send the condensate to facilities such as the riser waste heat recovery unit or the flue gas waste heat boiler for reuse.

[0003] The Chinese utility model patent with the application number 202023293473.5 discloses a low-grade waste heat recovery system for a coking production system. The coking production system includes a dry coke quenching boiler, a steam extraction condensing steam turbine, a condenser, a condensate pump, a generator, a crude benzene distillation unit, a deaerator, a deaerator feed pump, a demineralized water tank, a demineralized water station, a boiler feed pump, a continuous blowdown flash tank, a blowdown pump, and a dry coke quenching device water seal tank; the low-grade waste heat recovery system includes a primary water-water heat exchanger and a secondary water-water heat exchanger. The scheme can recover low-grade waste heat such as condensate and flash steam in the crude benzene distillation unit, continuous blowdown water and secondary steam in the dry coke quenching boiler during the coking production process.

[0004] In the prior art, after the condensate recovery station uses the condensate separation tank to recover the condensate, the condensate pump is used to transport the condensate to each unit tank. This not only increases the unnecessary land occupation of the condensate separation tank, but also wastes the back pressure of the condensate, increasing the operating cost; moreover, the production condensate is cooled by circulating cooling water, wasting the heat in the production condensate and consuming a large amount of circulating cooling water, which is very uneconomical. Summary of the Utility Model

[0005] The purpose of the utility model is to provide an optimized system for condensate recovery and reuse, overcoming the deficiencies of the prior art. The condensate recovery station in the existing scheme is cancelled, and the plant condensate directly enters the demineralized water tank of the flue gas waste heat boiler through back pressure. The high-temperature condensate exchanges heat with the deaerated feed water of the riser waste heat recovery pump station to recover the heat of the condensate, thereby saving investment, land occupation and operating cost. At the same time, the heat of the high-temperature condensate is recovered, the consumption of circulating cooling water is saved, and the energy utilization rate of coking enterprises is improved.

[0006] To achieve the above purpose, the utility model is realized through the following technical solutions:

[0007] An optimized system for condensate recovery and reuse, including a demineralized water tank of the riser pump station, a deaeration water pump of the riser pump station, a deaerator of the riser pump station, a demineralized water tank of the flue gas waste heat boiler, a deaeration water pump of the flue gas waste heat boiler, and a deaerator of the flue gas waste heat boiler. It is characterized in that the steam inlet of the deaerator of the riser pump station is communicated with the steam outlet of the flash tank, the water inlet of the deaerator of the riser pump station is communicated with the medium outlet of the water-water heat exchanger, the water outlet of the flash tank is communicated with the inlet of the inner tube of the water-water heat exchanger, the outlet of the inner tube of the water-water heat exchanger is communicated with the demineralized water tank of the flue gas waste heat boiler, and the medium inlet of the water-water heat exchanger is connected with the demineralized water tank of the riser pump station through the deaeration water pump of the riser pump station; the demineralized water tank of the flue gas waste heat boiler is connected with the deaerator of the flue gas waste heat boiler through the deaeration water pump of the flue gas waste heat boiler; the steam inlet of the flash tank is connected with a 0.6MPa saturated high-temperature condensate pipe.

[0008] The tops of the demineralized water tank of the riser pump station and the demineralized water tank of the flue gas waste heat boiler are connected through a connecting pipe, and a valve is provided on the connecting pipe.

[0009] The deaerated feed water of the riser deaeration pump station comes from external low-temperature condensate and external demineralized water.

[0010] The inner tube of the water-water heat exchanger contains 0.3MPa saturated condensate.

[0011] The demineralized water tanks of the riser pump station and the flue gas waste heat boiler and their corresponding deaeration water pumps can be arranged together.

[0012] Any one of the deaerators of the riser pump station and the deaerator of the flue gas waste heat boiler is a spin film deaerator or a spray packing deaerator.

[0013] The demineralized water tanks of the riser pump station and the flue gas waste heat boiler are both sealed tanks, and a liquid level gauge is provided on them.

[0014] The deaeration water pumps of the riser pump station and the flue gas waste heat boiler are both centrifugal pumps.

[0015] The water-water heat exchanger is a shell-and-tube heat exchanger or a plate heat exchanger.

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

[0017] 1) The demineralized water tanks of the flue gas waste heat boiler unit and the riser pump station realize the direct recovery of plant condensate by using condensate back pressure, replacing the function of the condensate separation tank in the existing scheme, saving investment and land occupation, and saving the operating cost of the condensate pump.

[0018] 2) Using the deaerated feed water of the riser pump station to exchange heat with high-temperature condensate reduces the consumption of circulating cooling water and recovers the heat of the high-temperature condensate.

[0019] 3) The steam generated by the flashing of high-temperature condensate enters the deaerator to heat and deaerate the feed water, saving the steam for external heating and realizing the cascade utilization of energy.

[0020] 4) The demineralized water tanks and their deaeration water pumps of the riser pumping station and the flue gas waste heat boiler can be arranged together, increasing the flexibility of condensate recovery and utilization and further saving land occupation. Description of the Drawings

[0021] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0022] In the figure: 1 - flash tank, 2 - water-water heat exchanger, 3 - demineralized water tank of the riser pumping station, 4 - deaeration water pump of the riser pumping station, 5 - deaerator of the riser pumping station, 6 - demineralized water tank of the flue gas waste heat boiler, 7 - deaeration water pump of the flue gas waste heat boiler, 8 - deaerator of the flue gas waste heat boiler, 9 - connecting pipe. Detailed Embodiments

[0023] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with specific embodiments. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments.

[0024] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the specific embodiments required for use in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other specific embodiments can be obtained based on these specific embodiments.

[0025] Generally, the components of the embodiments of the present invention described and shown in the specific embodiments here can be arranged and designed in countless different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the present invention claimed, but merely represents the selected embodiments of the present invention.

[0026] See Figure 1, which is a schematic structural diagram of an optimized system embodiment for condensate recovery and reuse of the present utility model, includes a demineralized water tank 3 of the upcomer pumping station, a deaeration water pump 4 of the upcomer pumping station, a deaerator 5 of the upcomer pumping station, a demineralized water tank 6 of the flue gas waste heat boiler, a deaeration water pump 7 of the flue gas waste heat boiler, and a deaerator 8 of the flue gas waste heat boiler. The steam inlet of the deaerator 5 of the upcomer pumping station is communicated with the steam outlet of the flash tank 1. The water inlet of the deaerator 5 of the upcomer pumping station is communicated with the medium outlet of the water-water heat exchanger 2. The water outlet of the flash tank 1 is communicated with the inner pipe inlet of the water-water heat exchanger 2. The inner pipe outlet of the water-water heat exchanger 2 is communicated with the demineralized water tank 6 of the flue gas waste heat boiler. The medium inlet of the water-water heat exchanger 2 is connected with the demineralized water tank 3 of the upcomer pumping station through the deaeration water pump 4 of the upcomer pumping station. The demineralized water tank 6 of the flue gas waste heat boiler is communicated with the deaerator 8 of the flue gas waste heat boiler through the deaeration water pump 7 of the flue gas waste heat boiler. The steam inlet of the flash tank 1 is connected with the 0.6 MPa saturated high-temperature condensate pipe. The inner pipe of the water-water heat exchanger 2 contains 0.3 MPa saturated condensate. After passing through the water-water heat exchanger 2, the temperature of the high-temperature condensate drops to 60 - 80 °C.

[0027] The tops of the demineralized water tank 3 of the upcomer pumping station and the demineralized water tank 6 of the flue gas waste heat boiler are connected through a connecting pipe 9, and a valve is provided on the connecting pipe 9. The deaerated feed water of the upcomer deaeration pumping station comes from external low-temperature condensate and external demineralized water, with a temperature of 20 - 50 °C. The temperature of the medium outlet of the water-water heat exchanger 2 is 60 - 80 °C. The demineralized water tanks of the upcomer pumping station and the flue gas waste heat boiler and their corresponding deaeration water pumps can be arranged together, that is, only the demineralized water tank 3 of the upcomer pumping station and the deaeration water pump 4 of the upcomer pumping station are retained, or only the demineralized water tank 6 of the flue gas waste heat boiler and the deaeration water pump 7 of the flue gas waste heat boiler are retained. When the flue gas waste heat boiler is under maintenance, the condensate can enter the demineralized water tank 3 of the upcomer pumping station, which can increase the flexibility of condensate recovery and utilization and can further save land.

[0028] Any one of the deaerator 5 of the upcomer pumping station and the deaerator 8 of the flue gas waste heat boiler is a spin film type deaerator or a spray packing type deaerator. The demineralized water tanks 3 of the upcomer pumping station and 6 of the flue gas waste heat boiler are both sealed tanks, and a liquid level gauge is provided thereon, which can be used to collect the liquid level height information. The deaeration water pumps 4 of the upcomer pumping station and 7 of the flue gas waste heat boiler are both centrifugal pumps. The water-water heat exchanger 2 is preferably a shell and tube heat exchanger, and a plate heat exchanger can also be selected.

[0029] In the embodiment of the present utility model, 0.6 MPa high-temperature saturated condensed water in the chemical engineering unit enters the flash tank 1. The 0.3 MPa saturated steam generated by flashing enters the deaerator 5 of the riser pump station to heat the deaerated feed water of the riser pump station. The 0.3 MPa saturated condensed water generated by flashing enters the water-water heat exchanger 2 to exchange heat with the deaerated feed water of the riser pump station. The deaerated feed water of the riser deaeration pump station comes from external low-temperature condensed water and external desalted water, with a temperature of about 25 - 50 °C. After these two incoming water streams enter the demineralized water tank of the 3 riser pump station, they are boosted by the riser deaeration water pump 4 and sent to the water-water heat exchanger 2 to exchange heat with the 0.3 MPa saturated condensed water, and then enter the deaerator 5 of the riser pump station; after the high-temperature condensed water exchanges heat through the water-water heat exchanger 2, it enters the demineralized water tank of the 6 flue gas waste heat boiler, and is boosted by the flue gas waste heat boiler deaeration water pump 7 and sent to the flue gas waste heat utilization deaerator 8.

[0030] Although the embodiments of the present utility model have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. An optimization system for condensate recovery and reuse, comprising a riser pump station desalted water tank, a riser pump station deoxygenation water pump, a riser pump station deaerator, a flue gas waste heat boiler desalted water tank, a flue gas waste heat boiler deoxygenation water pump, and a flue gas waste heat boiler deaerator, characterized in that: The steam inlet of the deaerator of the riser pump station is connected with the steam outlet of the flash tank, the water inlet of the deaerator of the riser pump station is connected with the medium outlet of the water-to-water heat exchanger, the water outlet of the flash tank is connected with the inner tube inlet of the water-to-water heat exchanger, the inner tube outlet of the water-to-water heat exchanger is connected with the desalting water tank of the flue gas waste heat boiler, and the medium inlet of the water-to-water heat exchanger is connected with the desalting water tank of the riser pump station via the deaerator water pump of the riser pump station; the desalting water tank of the flue gas waste heat boiler is connected with the deaerator of the flue gas waste heat boiler via the deaerator water pump of the flue gas waste heat boiler; the steam inlet of the flash tank is connected with the 0.6MPa saturated high-temperature condensate water pipe.

2. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The tops of the desalted water tank of the riser pump station and the desalted water tank of the flue gas waste heat boiler are connected through a connecting pipe, and a valve is provided on the connecting pipe.

3. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The deoxygenated water supply of the desalted water tank of the riser pump station comes from external low-temperature condensed water and external desalted water.

4. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The inner tube of the water-to-water heat exchanger contains 0.3 MPa saturated condensate water.

5. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The riser pump station and the desalted water tank of the flue gas waste heat boiler and its corresponding deoxygenated water pump can be arranged together.

6. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: Any one of the riser pump station deaerator and the flue gas waste heat boiler deaerator is a rotary film deaerator or a spray packing deaerator.

7. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The desalted water tank of the riser pump station and the desalted water tank of the flue gas waste heat boiler are both sealed tanks, on which liquid level gauges are arranged.

8. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The deaeration water pump of the riser pump station and the deaeration water pump of the flue gas waste heat boiler are both centrifugal pumps.

9. The optimization system for condensate recovery and reuse according to claim 1, characterized in that: The water-to-water heat exchanger is a shell-and-tube heat exchanger or a plate heat exchanger.

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