Mechanical seal water system for evaporative crystallization system

Abstract

The utility model discloses a mechanical seal water system for an evaporative crystallization system, and particularly relates to the technical field of mechanical seal water systems, which comprises a mechanical seal water tank and a pretreatment reuse water pipeline connected and communicated with a water supply pipeline of the mechanical seal water tank. A water outlet pipeline of the mechanical seal water tank is connected and communicated with a water inlet of the mechanical seal water pump, a water outlet of the mechanical seal water pump is connected and communicated with a water return pipeline of the mechanical seal water tank, the temperature of reuse water in the pretreatment reuse water pipeline is 28-30 DEG C, and the conductivity is lower than 750. According to the utility model, the service cycle of each pump seal of the evaporative crystallization system can be prolonged, the maintenance cost is saved, and the operation cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of mechanical seal water systems, in particular to a mechanical seal water system for an evaporation crystallization system. Background Technique

[0002] Centrifugal pumps, axial flow pumps, etc. are often used in evaporation crystallization systems. Most of these pumps need to use mechanical seal water according to process requirements. Traditional mechanical seal water is generally production water or primary condensate. Among them, the hardness of production water is relatively high, generally 700mg / L. A high hardness of production water means that there are more calcium, magnesium and other ions in the water. These ions are prone to form scale during the heating process, attach to the inside of the equipment, affect the heat exchange efficiency, and even cause mechanical seal damage, resulting in a shortened operation cycle of the evaporation crystallization unit, increased maintenance frequency and system maintenance cost; the primary condensate is the liquid after steam condensation. When the primary condensate is used as mechanical seal water, it needs to be heat-exchanged through a heat exchanger and then introduced into the mechanical seal water system for use. Although the hardness of the primary condensate is low, its temperature is relatively high. After heat exchange through the heat exchanger, the temperature is still between 50°C and 55°C. Long-term use of the primary condensate is likely to cause damage to the mechanical seal. Content of the Utility Model

[0003] The purpose of the utility model is to provide a mechanical seal water system for an evaporation crystallization system to solve the problems existing in the above-mentioned prior art, which can extend the service life of the mechanical seals of each machine pump in the evaporation crystallization system, save maintenance costs and reduce operating costs.

[0004] To achieve the above purpose, the utility model provides the following scheme:

[0005] The utility model provides a mechanical seal water system for an evaporation crystallization system, including a mechanical seal water tank and a pre-treated recycled water pipeline. The pre-treated recycled water pipeline is connected and communicated with the water supply pipeline of the mechanical seal water tank. The water outlet pipeline of the mechanical seal water tank is connected and communicated with the water inlet of a mechanical seal water pump. The water outlet of the mechanical seal water pump is connected and communicated with the water return pipeline of the mechanical seal water tank. The temperature of the recycled water in the pre-treated recycled water pipeline is 28 - 30°C, and the conductivity is lower than 750 us / cm.

[0006] Preferably, it further includes a production water pipeline, which is connected and communicated with the water supply pipeline of the mechanical seal water tank. The temperature of the production water in the production water pipeline is 18 - 25°C, and the conductivity is 1200 - 1400 us / cm.

[0007] Preferably, it further includes a primary condensate pipeline, which is connected and communicated with the water supply pipeline of the mechanical seal water tank. The temperature of the primary condensate in the primary condensate pipeline is 90 - 100°C, and the conductivity is lower than 20 us / cm.

[0008] Preferably, it further includes a control device. Valves are provided on the pre-treated recycled water pipeline, the production water pipeline, and the primary condensate pipeline. Each of the valves is in signal connection with the control device, and the control device is configured to be able to control one valve to open and the rest of the valves to close.

[0009] Preferably, a three-way valve, a temperature sensor, and a conductivity meter are provided on the return water pipeline of the mechanical seal water tank. The two ends of the three-way valve are respectively connected and communicated with the return water pipeline of the mechanical seal water tank, and the other end is communicated with the drainage pipeline. The three-way valve is closer to the mechanical seal water tank than the temperature sensor and the conductivity meter. The three-way valve, the temperature sensor, and the conductivity meter are all in signal connection with the control device.

[0010] Preferably, an automatic regulating valve for adjusting the water inflow is provided on the water supply pipeline.

[0011] Preferably, the automatic regulating valve is in signal connection with the control device.

[0012] The utility model has achieved the following technical effects compared with the prior art:

[0013] The utility model provides a mechanical seal water system for an evaporation crystallization system. The recycled water in the pre-treated recycled water pipeline is used to replace the production water with a relatively high hardness as the mechanical seal water. The temperature of the recycled water is 28 - 30 °C, which has a small impact on the heat exchange efficiency of the heat exchanger circulating water, extends the service life of the mechanical seals of each pump in the evaporation crystallization system, and the conductivity of the recycled water is lower than 750 us / cm, with low hardness, which can reduce the scaling problem, save maintenance costs, and reduce the operating cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0015] Figure 1 It is a schematic diagram of a mechanical seal water system for an evaporation crystallization system.

[0016] In the figure: 1 - mechanical seal water tank; 2 - pre-treated recycled water pipeline; 3 - production water pipeline; 4 - primary condensate pipeline; 5 - valve; 6 - water supply pipeline; 7 - outlet water pipeline; 8 - automatic regulating valve; 9 - return water pipeline; 10 - three-way valve; 11 - drainage pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying 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. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0018] The purpose of the present invention is to provide a mechanical seal water system for an evaporation crystallization system to solve the problems existing in the above-mentioned prior art, which can extend the service life of the mechanical seals of each pump in the evaporation crystallization system, save maintenance costs, and reduce operating costs.

[0019] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0020] Embodiment 1

[0021] This embodiment provides a mechanical seal water system for an evaporation crystallization system. As Figure 1 shown, it includes a mechanical seal water tank 1 and a pre-treated recycled water pipeline 2. The pre-treated recycled water pipeline 2 is connected and communicated with the water supply pipeline 6 of the mechanical seal water tank 1. The water outlet pipeline 7 of the mechanical seal water tank 1 is connected and communicated with the water inlet of the mechanical seal water pump to supply mechanical seal water to the mechanical seal water pump. The water outlet of the mechanical seal water pump is connected and communicated with the water return pipeline 9 of the mechanical seal water tank 1. The temperature of the recycled water in the pre-treated recycled water pipeline 2 is 28 - 30 °C, and the conductivity is less than 750 us / cm. Using the recycled water in the pre-treated recycled water pipeline 2 to replace the production water with relatively high hardness as the mechanical seal water, the temperature of the recycled water is 28 - 30 °C, which has little influence on the heat exchange efficiency of the heat exchanger circulating water in the pipeline leading the mechanical seal water to the mechanical seal water pump, extends the service life of the mechanical seals of each pump in the evaporation crystallization system, and the conductivity of the recycled water is less than 750 us / cm, with low hardness, which can reduce the scaling problem, save maintenance costs, and reduce operating costs.

[0022] In a further preferred embodiment of this embodiment, the mechanical seal water system for the evaporation crystallization system further includes a production water pipeline 3. The production water pipeline 3 is connected and communicated with the water supply pipeline 6 of the mechanical seal water tank 1. The temperature of the production water in the production water pipeline 3 is 18 - 25 °C, and the conductivity is 1200 - 1400 us / cm.

[0023] In a further preferred embodiment of this embodiment, the mechanical seal water system for the evaporation crystallization system further includes a primary condensate pipeline 4. The primary condensate pipeline 4 is connected and communicated with the water supply pipeline 6 of the mechanical seal water tank 1. The temperature of the primary condensate in the primary condensate pipeline 4 is 90 - 100 °C, and the conductivity is less than 20 us / cm.

[0024] Further preferably, in the implementation manner of this embodiment, the mechanical seal water system for the evaporation crystallization system further includes a control device. Valves 5 are provided on the pre-treated recycled water pipeline 2, the production water pipeline 3, and the primary condensate pipeline 4. Each valve 5 is in signal connection with the control device, and the control device is configured to be able to control one valve 5 to open and the remaining valves 5 to close.

[0025] Further preferably, in the implementation manner of this embodiment, a three-way valve 10, a temperature sensor, and a conductivity meter are provided on the return water pipeline 9 of the mechanical seal water tank 1. The two ends of the three-way valve 10 are respectively connected to and communicated with the return water pipeline 9 of the mechanical seal water tank 1, and the other end is communicated with the drainage pipeline 11. The three-way valve 10 is closer to the mechanical seal water tank 1 than the temperature sensor and the conductivity meter. The three-way valve 10, the temperature sensor, and the conductivity meter are all in signal connection with the control device.

[0026] Further preferably, in the implementation manner of this embodiment, an automatic regulating valve 8 for adjusting the water inflow is provided on the water supply pipeline 6, which can timely adjust the size of the water supply according to actual needs.

[0027] Further preferably, in the implementation manner of this embodiment, the automatic regulating valve 8 is in signal connection with the control device.

[0028] Embodiment 2

[0029] This embodiment provides an operation method for the mechanical seal water system for the evaporation crystallization system of Embodiment 1.

[0030] When the temperature of the seal water in the seal water tank 1 detected by the temperature sensor is lower than 50°C and the conductivity of the seal water in the seal water tank 1 detected by the conductivity meter is lower than 8000 us / cm, the control device controls the valve 5 on the production water pipeline 3 and the valve 5 on the primary condensate pipeline 4 to close, and opens the valve 5 on the pre-treated recycled water pipeline 2. The recycled water in the pre-treated recycled water pipeline 2 is used as supplementary seal water and introduced into the seal water tank 1; when the temperature of the recycled water in the seal water tank 1 detected by the temperature sensor is higher than 50°C, the control device controls the three-way valve 10 to discharge the high-temperature seal water to the outside, and opens the valve 5 on the production water pipeline 3. The production water in the production water pipeline 3 is used as seal water and introduced into the seal water tank 1 to replace the high-temperature seal water and reduce the temperature of the seal water. When the temperature of the seal water in the seal water tank 1 detected by the temperature sensor is lower than 40°C (the set temperature can be adjusted according to the actual operation situation), the control device controls the valve 5 on the production water pipeline 3 to close and opens the valve 5 on the pre-treated recycled water pipeline 2. After a period of time, that is, after the recycled water replaces the primary condensate again, the control device controls the three-way valve 10 to make the water discharged from the seal water pump flow into the seal water tank 1; when there is material leakage into the seal water, the conductivity of the seal water will change. When the conductivity of the seal water in the seal water tank 1 detected by the conductivity meter is higher than 8000 us / cm, the control device controls the three-way valve 10 to discharge the high-conductivity seal water to the outside, and opens the valve 5 on the primary condensate pipeline 4. The primary condensate in the primary condensate pipeline 4 is used as seal water and introduced into the seal water tank 1. Since the conductivity of the primary condensate is lower than 20 us / cm, it can replace the conductivity of the high-conductivity seal water to be qualified at the fastest speed, reduce the conductivity of the seal water, and prevent the seal from being damaged due to high conductivity and high salt content of the seal water; when the conductivity of the seal water in the seal water tank 1 detected by the conductivity meter is lower than 4000 us / cm (the conductivity can be adjusted according to the actual situation), the control device controls and closes the valve 5 on the primary condensate pipeline 4 and opens the valve 5 on the pre-treated recycled water pipeline 2. After a period of time, that is, after the recycled water replaces the primary condensate again, the control device controls the three-way valve 10 to make the water discharged from the seal water pump flow into the seal water tank 1. The seal water system for the evaporation crystallization system can detect the temperature and conductivity of the seal water in a timely manner. When the temperature or conductivity of the seal water exceeds the set value, it can replace the appropriate seal water pipeline in a timely manner to ensure the stable operation of the entire seal water system and the evaporation crystallization unit. When both the conductivity and the temperature exceed the set value, the conductivity is given priority.

[0031] In the present utility model, specific examples are used to elaborate the principle and implementation manner of the present utility model. The description of the above embodiments is only used to help understand the method and its core idea of the present utility model; at the same time, for those of ordinary skill in the art, according to the idea of the present utility model, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present utility model.

Claims

1. A mechanical sealing water system for an evaporation crystallization system, characterized in that: It includes a machine-sealed water tank and a pre-treatment reuse water pipeline, wherein the pre-treatment reuse water pipeline is connected and communicated with the water supply pipeline of the machine-sealed water tank, the water outlet pipeline of the machine-sealed water tank is connected and communicated with the water inlet of a machine-sealed water pump, the water outlet of the machine-sealed water pump is connected and communicated with the return water pipeline of the machine-sealed water tank, and the reuse water temperature in the pre-treatment reuse water pipeline is 28-30°C, and the conductivity is lower than 750us / cm.

2. The mechanical sealing water system for the evaporation crystallization system according to claim 1, characterized in that: It also includes a production water pipeline, which is connected and communicated with the water supply pipeline of the machine-sealed water tank. The temperature of the production water in the production water pipeline is 18-25° C., and the conductivity is 1200-1400 us / cm.

3. The mechanical sealing water system for the evaporation crystallization system according to claim 2, characterized in that: It also includes a primary condensate pipeline, which is connected and communicated with the water supply pipeline of the machine sealing water tank. The primary condensate temperature in the primary condensate pipeline is 90-100° C. and the conductivity is lower than 20 us / cm.

4. The mechanical sealing water system for the evaporation crystallization system according to claim 3, characterized in that: It also includes a control device. The pretreatment reuse water pipeline, the production water pipeline and the primary condensate pipeline are all provided with valves. Each of the valves is connected to the control device by signal. The control device is configured to control one valve to open and the other valves to close.

5. The mechanical sealing water system for the evaporation crystallization system according to claim 4, characterized in that: A three-way valve, a temperature sensor and a conductivity meter are arranged on the return pipeline of the machine-sealed water tank. Both ends of the three-way valve are respectively connected and communicated with the return pipeline of the machine-sealed water tank, and the other end is communicated with the drainage pipeline. The three-way valve is closer to the machine-sealed water tank than the temperature sensor and the conductivity meter. The three-way valve, the temperature sensor and the conductivity meter are all connected to the control device signal.

6. The mechanical sealing water system for the evaporation crystallization system according to claim 4, characterized in that: The water supply pipeline is provided with an automatic regulating valve for regulating the water inlet.

7. The mechanical sealing water system for the evaporation crystallization system according to claim 6, characterized in that: The automatic regulating valve is connected to the control device by signal.

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