Flash evaporation system for sewage pretreatment

Abstract

A flash evaporation system for sewage pretreatment comprises a flash evaporation tank and a steam preheater, a wastewater inlet of the steam preheater is connected with a steam condensate preheater through a pipeline, and a wastewater outlet of the steam preheater is connected with a wastewater inlet of the flash evaporation tank through a pipeline. A condensate water inlet of the steam preheater is connected with a dirty condensate water tank through a pipeline, a condensate water outlet of the steam preheater is connected with a low-pressure steam tank through a pipeline, and a waste water outlet of the flash tank is connected with a first-effect heater through a pipeline. And a secondary steam outlet of the flash tank is connected with a secondary steam inlet of the flash condenser through a pipeline. According to the sodium sulfate wastewater treatment system, the flash evaporation cooling device is arranged, so that the treatment capacity of sodium sulfate wastewater is improved, damage and corrosion of equipment caused by blockage of the equipment are not easily caused, and the system is more perfect, the labor consumption is reduced and the economic performance is improved by additionally arranging a data detector and various valves on each system.

Description

Technical Field

[0001] The utility model relates to the technical field related to flash evaporation technology, in particular to a flash evaporation system for sewage pretreatment. Background Art

[0002] In industries such as chemical industry, hazardous waste incineration, petroleum refining, textile and food processing, high-salt wastewater is usually generated during the production process. These high-salt wastewaters contain high concentrations of salt, generally including various organic and inorganic compounds such as sodium chloride, sodium sulfate, sodium nitrate, etc. If these wastewaters are discharged directly, they will have a certain impact on the environment.

[0003] The main technologies currently used to treat this type of high-salinity wastewater include mechanical compression evaporation (MVR) and multiple-effect evaporation (MED). Both technologies are based on the principle of evaporation. By heating the wastewater, dissolved salts and other non-volatile substances are separated from the water, forming salt crystals and other solids. These salt crystals and other solids easily form scale on the inner surface of the heat exchanger, resulting in reduced thermal efficiency and may even cause equipment blockage, which will cause certain corrosion and damage to the equipment, and ultimately may lead to instability or even paralysis of the entire production system. Utility Model Content

[0004] The purpose of the utility model is to provide a flash evaporation system for sewage pretreatment, aiming to solve the above-mentioned technical problems. The utility model improves the treatment capacity of sodium sulfate wastewater by providing a flash evaporation condenser, and the equipment is not easily damaged or corroded due to clogging. In addition, by adding data detectors and various valves to each system, the degree of automation is improved, labor consumption is reduced, and economic performance is improved.

[0005] In order to achieve the above-mentioned purpose, the present invention is implemented through the following technical solutions:

[0006] A flash evaporation system for sewage pretreatment comprises a flash tank and a steam preheater, wherein the wastewater inlet of the steam preheater is connected to the steam condensate preheater through a pipeline, the wastewater outlet of the steam preheater is connected to the wastewater inlet of the flash tank through a pipeline, the condensate inlet of the steam preheater is connected to the waste condensate tank through a pipeline, the condensate outlet of the steam preheater is connected to the low-pressure steam tank through a pipeline, the wastewater outlet of the flash tank is connected to the primary heater through a pipeline, and the secondary steam outlet of the flash tank is connected to the secondary steam inlet of the flash condenser through a pipeline.

[0007] Furthermore, the dirty condensed water outlet of the flash condenser is connected to the dirty condensed water tank through a pipeline, the non-condensable gas outlet of the flash condenser is connected to the vacuum pump through a pipeline, the cooling water inlet of the flash condenser is connected to the cooling water main through a pipeline, and the cooling water outlet of the flash condenser is connected to the cooling water return pipe through a pipeline. The flash tank can condense high-temperature and high-pressure gas or steam into low-temperature and low-pressure liquid, and the flash condenser can convert secondary steam into non-condensable steam.

[0008] Furthermore, a thermometer and a ball valve are provided between the steam preheater and the steam condensate preheater. The ball valve can control the flow of sodium sulfate wastewater. The steam preheater can increase the temperature of the air entering the system through a heat exchange process, thereby enhancing the thermal efficiency and energy-saving effect of the system.

[0009] Furthermore, a ball valve, a thermometer and a liquid level regulating valve are provided between the steam preheater and the flash tank, and the liquid level regulating valve can control the flow of the liquid level.

[0010] Furthermore, a steam trap and a ball valve are provided between the steam preheater and the dirty condensate water tank.

[0011] Furthermore, a ball valve and a pressure regulating valve are provided between the steam preheater and the low-pressure steam tank.

[0012] Furthermore, a thermometer is provided between the flash tank and the flash condenser.

[0013] Furthermore, a thermometer, a flash transfer pump and a pressure gauge are provided between the flash tank and the first-effect heater, and the flash transfer pump is located between the thermometer and the pressure gauge.

[0014] Furthermore, a thermometer and a butterfly valve are provided between the flash condenser and the cooling water main pipe; a pressure gauge and a butterfly valve are provided between the flash condenser and the cooling water return pipe.

[0015] The utility model provides a flash evaporation system for sewage pretreatment, which has the following beneficial effects:

[0016] 1. The utility model provides a flash evaporation system for sewage pretreatment. This system forms a high-salinity wastewater treatment loop by combining a preheater, a flash tank, and a condenser. After being heated in the preheater, the high-salinity wastewater enters the flash tank, where it is effectively concentrated. Furthermore, the flash tank has no internal components, minimizing the risk of saline wastewater clogging within the equipment. This avoids the risk of equipment fouling and clogging, which could lead to instability or even paralysis of the overall production system.

[0017] 2. This utility model is a flash evaporation system for sewage pretreatment. It mainly relies on the flash steam from the flash tank to be introduced into the condenser to realize the transfer and utilization of steam heat, effectively reducing operating costs. At the same time, the condensed fresh water generated by the system can be supplemented to other process water consumption, achieving the effect of energy saving and emission reduction.

[0018] 3. The utility model is a flash evaporation system for sewage pretreatment. By adding various data detection devices and various valves to each system, the system is made more complete, eliminating the need for manual monitoring of the system at all times, reducing labor consumption, and contributing to cost reduction and efficiency improvement.

[0019] 4. The utility model provides a flash evaporation system for sewage pretreatment. The system structure is set to operate for a period of 4 months, which originally required the system to be stopped for high-pressure cleaning. Now it has been in operation for 4 months and there has been no significant decrease in heat exchange efficiency, which greatly improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an overall schematic diagram of the flash evaporation system for sewage pretreatment of the utility model;

[0021] Figure 2 This is a schematic diagram of the connection relationship between the steam preheater and the flash tank of the present invention;

[0022] Figure 3 This is a schematic diagram of the connection relationship between the flash tank and the flash feed pump of the present invention;

[0023] Figure 4 This is a schematic diagram of the connection relationship between the flash tank and the flash condenser of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in further detail below with reference to the embodiments and accompanying drawings.

[0025] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element; when an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended solely for the purpose of describing specific embodiments and are not intended to limit this invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] like Figures 1 to 4 As shown, a flash evaporation system for sewage pretreatment includes a flash tank 2 and a steam preheater 1, the wastewater inlet of the steam preheater 1 is connected to the steam condensate preheater 7 through a pipeline, the wastewater outlet of the steam preheater 1 is connected to the wastewater inlet of the flash tank 2 through a pipeline, the condensate inlet of the steam preheater 1 is connected to the waste condensate tank 6 through a pipeline, the condensate outlet of the steam preheater 1 is connected to the low-pressure steam tank 9 through a pipeline, the wastewater outlet of the flash tank 2 is connected to the primary heater 4 through a pipeline, and the secondary steam outlet of the flash tank 2 is connected to the secondary steam inlet of the flash condenser 3 through a pipeline.

[0028] It should be noted that: in this embodiment, after the sodium sulfate wastewater is produced from the steam condensate preheater 7, it enters the steam preheater 1 through a pipeline for heating. The heated sodium sulfate wastewater then enters the flash tank 2 through a pipeline for flash evaporation treatment. After treatment in the flash tank 2, secondary steam is formed. The secondary steam enters the flash condenser 3 through a pipeline for cooling treatment, and the sodium sulfate wastewater after treatment in the flash tank 2 is transported to the first-effect heater 4 through the flash transfer pump 175 for subsequent treatment.

[0029] like Figure 1 and Figure 4 As shown, the dirty condensed water outlet of the flash condenser 3 is connected to the dirty condensed water tank 6 through a pipeline, the non-condensable gas outlet of the flash condenser 3 is connected to the vacuum pump 5 through a pipeline, the cooling water inlet of the flash condenser 3 is connected to the cooling water main pipe 11 through a pipeline, and the cooling water outlet of the flash condenser 3 is connected to the cooling water return pipe 10 through a pipeline.

[0030] It should be noted that: in this embodiment, the secondary steam enters the flash condenser 3 for cooling treatment, the formed non-condensable gas is transported to the vacuum pump 5 through a pipeline, and the formed dirty condensed water is transported to the dirty condensed water tank 6 through a pipeline.

[0031] like Figure 1 and Figure 2As shown, a thermometer 12 and a ball valve 13 are provided between the steam preheater 1 and the steam condensate preheater 7. The ball valve 13 can control the flow rate of the pipeline liquid. The steam preheater 1 can increase the temperature of the liquid entering the system through the heat exchange process, thereby enhancing the thermal efficiency and energy-saving effect of the system.

[0032] like Figure 1 and Figure 2 As shown, a ball valve 13, a thermometer 12 and a liquid level regulating valve 14 are provided between the steam preheater 1 and the flash tank 2. The liquid level regulating valve 14 can control the flow of the liquid level.

[0033] like Figure 1 and Figure 2 As shown, a steam trap 15 and a ball valve 13 are provided between the steam preheater 1 and the dirty condensed water tank 6 , and the steam trap 15 and the ball valve 13 can control the flow of the dirty condensed water.

[0034] like Figure 1 and Figure 2 As shown, a ball valve 13 and a pressure regulating valve 16 are provided between the steam preheater 1 and the low-pressure steam tank 9. The low-pressure steam passes through the pressure regulating valve 16 to the steam preheater 1 for preheating and conversion into waste condensate.

[0035] like Figure 1 and Figure 4 As shown, a thermometer 12 is provided between the flash tank 2 and the flash condenser 3 .

[0036] like Figure 1 and Figure 3 As shown, a thermometer 12 , a flash transfer pump 17 and a pressure gauge 8 are provided between the flash tank 2 and the first-effect heater 4 , and the flash transfer pump 17 is located between the thermometer 12 and the pressure gauge 8 .

[0037] like Figure 1 and Figure 4 As shown, a thermometer 12 and a butterfly valve 18 are provided between the flash condenser 3 and the cooling water main pipe 11 ; a pressure gauge 8 and a butterfly valve 18 are provided between the flash condenser 3 and the cooling water return pipe 10 .

[0038] It should be noted that: in this embodiment, taking the treatment of sodium sulfate wastewater as an example, the sodium sulfate wastewater generated from the steam condensate preheater 7 is discharged to the steam preheater 1 through a pipeline, and heat exchange is achieved with the low-pressure steam on the steam preheater 1, so that the sodium sulfate wastewater is heated and then discharged to the flash tank 2 through a pipeline, and the flash tank 2 is flashed to form secondary steam, which is discharged from the upper part of the flash tank 2 to the flash condenser 3 for heat exchange and cooling, forming non-condensable steam and discharged to the vacuum pump 5 through a pipeline; and the sodium sulfate wastewater after passing through the flash tank 2 is discharged to the primary heater 4 through the flash feed pump 17.

[0039] In this embodiment, the secondary steam produced in the flash tank 2 is transferred to the flash condenser 3 through a pipeline. After the action of the flash condenser 3, the secondary steam is converted into non-condensable steam and transferred to the vacuum pump 5 through a pipeline. The flash condenser 3 requires a large amount of cooling water during operation. The cooling water flows from the cooling water main pipe 11 through a pipeline into the flash cooler, and then through a pipeline to the cooling water return pipe 10. After reaching the cooling water return pipe 10, the cooling water circulation loop achieves the purpose of cooling the flash condenser 3. The dirty condensed water condensed in the flash condenser 3 flows into the dirty condensed water tank 6 through a pipeline.

[0040] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any ordinary technician in the industry can smoothly implement the present invention as shown in the drawings and described above. However, any technician familiar with the profession can make some changes, modifications and equivalent changes made by using the technical content disclosed above without departing from the scope of the technical solution of the present invention, which are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention still belong to the technical solution of the present invention.

Claims

1. A flash evaporation system for sewage pretreatment, characterized by: It includes a flash tank and a steam preheater, the wastewater inlet of the steam preheater is connected to the steam condensate preheater through a pipeline, the wastewater outlet of the steam preheater is connected to the wastewater inlet of the flash tank through a pipeline, the condensate inlet of the steam preheater is connected to the dirty condensate tank through a pipeline, the condensate outlet of the steam preheater is connected to the low-pressure steam tank through a pipeline, the wastewater outlet of the flash tank is connected to the first-effect heater through a pipeline, and the secondary steam outlet of the flash tank is connected to the secondary steam inlet of the flash condenser through a pipeline.

2. A flash evaporation system for sewage pretreatment according to claim 1, characterized in that: The dirty condensed water outlet of the flash condenser is connected to the dirty condensed water tank through a pipeline, the non-condensable gas outlet of the flash condenser is connected to the vacuum pump through a pipeline, the cooling water inlet of the flash condenser is connected to the cooling water main pipe through a pipeline, and the cooling water outlet of the flash condenser is connected to the cooling water reflux pipe through a pipeline.

3. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A thermometer and a ball valve are provided between the steam preheater and the steam condensate preheater.

4. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A ball valve, a thermometer and a liquid level regulating valve are provided between the steam preheater and the flash tank.

5. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A steam trap and a ball valve are provided between the steam preheater and the dirty condensed water tank.

6. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A ball valve and a pressure regulating valve are provided between the steam preheater and the low-pressure steam tank.

7. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A thermometer is provided between the flash tank and the flash condenser.

8. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A thermometer, a flash distillation feed pump and a pressure gauge are provided between the flash tank and the first-effect heater, and the flash distillation feed pump is located between the thermometer and the pressure gauge.

9. The flash evaporation system for sewage pretreatment according to claim 1, characterized in that: A thermometer and a butterfly valve are provided between the flash condenser and the cooling water main pipe; a pressure gauge and a butterfly valve are provided between the flash condenser and the cooling water return pipe.

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