Treatment system for wastewater containing high-boiling-point organic matters

Abstract

The utility model relates to the technical field of wastewater treatment, in particular to a treatment system for wastewater containing high-boiling-point organic matters, which comprises a stripping tower, a feed port of the stripping tower is connected with a wastewater feed pipe, a liquid outlet at the bottom of the stripping tower is connected with a first-effect evaporator through a pipeline, and the first-effect evaporator is connected with a second-effect evaporator through a pipeline. The second-effect evaporator is connected with a third-effect evaporator through a pipeline; the second-effect evaporator is used for receiving an evaporation concentrated solution of the first-effect evaporator, and the third-effect evaporator is used for receiving an evaporation concentrated solution of the second-effect evaporator; a gas outlet in the top of the stripping tower is connected with a condenser through a pipeline; the condenser is connected with a chromatography device through a pipeline; according to the device disclosed by the utility model, heavy components, light components and water can be finally separated and respectively recovered, heavy component materials concentrated by the triple-effect evaporator are rectified and recovered, the light components are waste oil to be sold, and the recovered water is secondarily utilized.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to a wastewater treatment system containing high-boiling organic substances. Background Art

[0002] The organic wastewater generated during aldol condensation contains organic substances with relatively high boiling points. Currently, the main wastewater treatment technologies for such wastewater include the air flotation method and the air catalytic oxidation method.

[0003] The air flotation method refers to the process of using highly dispersed minute bubbles as carriers to adhere to the pollutants in the wastewater, making their buoyancy greater than the gravity and the upward resistance, so that the pollutants float to the water surface to form foam, and then using a slag scraping device to scrape the foam from the water surface to achieve solid-liquid or liquid-liquid separation. The necessary conditions for the air flotation process are: in the wastewater to be treated, a large number of fine bubbles should be distributed, and the pollutants to be treated should be in a suspended state, and the surface of the suspended particles should be hydrophobic and easy to adhere to the bubbles and float. The oily wastewater containing high-boiling substances contains organic substances that are easily soluble in water, and the air flotation method has a low removal rate of organic substances with high boiling points.

[0004] The air catalytic oxidation method refers to the catalytic oxidation reaction of the pollutants in the wastewater by air. However, the air catalytic oxidation method has a low removal rate of the oil content in the wastewater.

[0005] The existing treatment technologies have low removal rates of organic substances and oil in the wastewater and cannot meet the treatment requirements. Summary of the Utility Model

[0006] The main purpose of the utility model is to provide a wastewater treatment system containing high-boiling organic substances to solve the problems in the above-mentioned existing technologies.

[0007] To achieve the above purpose, the utility model provides a wastewater treatment system containing high-boiling organic substances, including a stripping tower. The feed inlet of the stripping tower is connected to a wastewater feed pipe. The bottom liquid outlet of the stripping tower is connected to a first-effect evaporator through a pipeline. The first-effect evaporator is connected to a second-effect evaporator through a pipeline. The second-effect evaporator is connected to a third-effect evaporator through a pipeline. The second-effect evaporator is used to receive the evaporation concentrate of the first-effect evaporator, and the third-effect evaporator is used to receive the evaporation concentrate of the second-effect evaporator.

[0008] Further, a first-effect circulation pipe is connected between the first heat exchange medium inlet and the first heat exchange medium outlet of the first-effect evaporator. An first-effect gas-liquid separation tank and an first-effect circulation pump are connected to the first-effect circulation pipe. A second-effect circulation pipe is connected between the first heat exchange medium inlet and the first heat exchange medium outlet of the second-effect evaporator. A second-effect gas-liquid separation tank and a second-effect circulation pump are connected to the second-effect circulation pipe. A third-effect circulation pipe is connected between the first heat exchange medium inlet and the first heat exchange medium outlet of the third-effect evaporator. A third-effect gas-liquid separation tank, a third-effect circulation pump and a discharge pipe are connected to the third-effect circulation pipe.

[0009] Further, a steam inlet pipe is connected to the second heat exchange medium inlet of the triple-effect evaporator. The second heat exchange medium outlet of the triple-effect evaporator is connected to a triple-effect flash tank through a pipeline. The gas outlet at the top of the triple-effect flash tank is connected to the second heat exchange medium inlet of the double-effect evaporator through a pipeline. The second heat exchange medium outlet of the double-effect evaporator is connected to a double-effect flash tank through a pipeline. The gas outlet at the top of the double-effect flash tank is connected to the second heat exchange medium inlet of the single-effect evaporator through a pipeline. The second heat exchange medium outlet of the single-effect evaporator is connected to a single-effect flash tank through a pipeline.

[0010] Further, the gas outlets at the tops of the single-effect flash tank, the double-effect flash tank, and the triple-effect flash tank are all connected to a second vapor outlet pipe through pipelines. A vapor outlet cooler is connected to the second vapor outlet pipe. The liquid outlets at the bottoms of the single-effect flash tank, the double-effect flash tank, and the triple-effect flash tank are all connected to a flash liquid pipe through pipelines. Both the second vapor outlet pipe and the flash liquid pipe are connected to a storage tank, and the storage tank (9) is connected to a liquid outlet pump.

[0011] Further, the gas outlet at the top of the stripping column is connected to a condenser through a pipeline. The condenser is connected to a chromatograph through a pipeline. The liquid outlet at the bottom of the chromatograph is connected to an oil-phase centrifugal pump and an aqueous-phase centrifugal pump through pipelines. The oil-phase centrifugal pump is connected to an oil-phase recovery tank through a pipeline. The aqueous-phase centrifugal pump is connected to an aqueous-phase recovery tank through a pipeline.

[0012] Further, the gas outlets at the tops of the single-effect evaporator, the double-effect evaporator, the triple-effect evaporator, and the chromatograph are all connected to a first vapor outlet pipe through pipelines. A vacuum pump is connected to the first vapor outlet pipe. The first vapor outlet pipe is connected to a storage tank.

[0013] Further, the bottom of the stripping column is connected to a reboiler. A first feed pump and a preheater are connected to the pipeline between the stripping column and the single-effect evaporator.

[0014] The beneficial effects of the present utility model are as follows:

[0015] By providing a stripping column, organic substances with light components in the wastewater can be distilled out. By providing a single-effect evaporator, a double-effect evaporator, and a triple-effect evaporator, water in the wastewater can be distilled out, separating high-boiling-point heavy-component organic substances from water. Thus, water is recycled and waste is treated.

[0016] Ultimately, the present utility model can separate heavy components, light components, and water and recycle them separately. The heavy-component material concentrated by the triple-effect evaporator is subjected to rectification and recovery. The light components are sold as waste oil, and the recycled water is reused. Description of the Drawings

[0017] The accompanying drawings of the specification, which form a part of this application, are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and shall not constitute an improper limitation to the present utility model.

[0018] Figure 1 It is a schematic structural diagram of a high-boiling organic matter wastewater treatment system in the embodiment.

[0019] In the figure: 1. Stripping tower; 1.1. Condenser; 1.2. Chromatograph; 1.3. Oil-phase centrifugal pump; 1.4. Water-phase centrifugal pump; 1.5. Oil-phase recovery tank; 1.6. Water-phase recovery tank; 1.7. Reboiler; 1.8. First-effect feed pump; 1.9. Preheater; 2. First-effect evaporator; 2.1. First-effect gas-liquid separation tank; 2.2. First-effect circulation pump; 2.3. First-effect flash tank; 3. Second-effect evaporator; 3.1. Second-effect gas-liquid separation tank; 3.2. Second-effect circulation pump; 3.3. Second-effect flash tank; 4. Third-effect evaporator; 4.1. Third-effect gas-liquid separation tank; 4.2. Third-effect circulation pump; 4.3. Third-effect flash tank; 5. Steam inlet pipe; 6. First vapor discharge pipe; 6.1. Vacuum pump; 7. Second vapor discharge pipe; 7.1. Vapor discharge cooler; 8. Flash liquid pipe; 9. Liquid storage tank; 10. Discharge pipe; 11. Wastewater feed pipe; 12. Liquid discharge pump. Detailed implementation manners

[0020] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments may be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0021] Embodiment of a high-boiling organic matter wastewater treatment system

[0022] As Figure 1 shown, a high-boiling organic matter wastewater treatment system is provided, which includes a stripping tower 1. The feed inlet of the stripping tower 1 is connected to the wastewater feed pipe 11. The bottom liquid outlet of the stripping tower 1 is connected to the first-effect evaporator 2 through a pipeline. The first-effect evaporator 2 is connected to the second-effect evaporator 3 through a pipeline. The second-effect evaporator 3 is connected to the third-effect evaporator 4 through a pipeline. The second-effect evaporator 3 is used to receive the evaporation concentrate of the first-effect evaporator 2, and the third-effect evaporator 4 is used to receive the evaporation concentrate of the second-effect evaporator 3.

[0023] The bottom of the stripping tower 1 is connected with a reboiler 1.7, and a first-effect feed pump 1.8 and two preheaters 1.9 are connected to the pipeline between the stripping tower 1 and the first-effect evaporator 2.

[0024] A first heat exchange medium inlet and a first heat exchange medium outlet of the first-effect evaporator 2 are connected by a first-effect circulation pipe, and a first-effect gas-liquid separation tank 2.1 and a first-effect circulation pump 2.2 are connected to the first-effect circulation pipe; a first heat exchange medium inlet and a first heat exchange medium outlet of the second-effect evaporator 3 are connected by a second-effect circulation pipe, and a second-effect gas-liquid separation tank 3.1 and a second-effect circulation pump 3.2 are connected to the second-effect circulation pipe; a first heat exchange medium inlet and a first heat exchange medium outlet of the third-effect evaporator 4 are connected by a third-effect circulation pipe, and a third-effect gas-liquid separation tank 4.1, a third-effect circulation pump 4.2 and a discharge pipe 10 are connected to the third-effect circulation pipe.

[0025] A steam inlet pipe 5 is connected to a second heat exchange medium inlet of the third-effect evaporator 4, a third-effect flash tank 4.3 is connected to a second heat exchange medium outlet of the third-effect evaporator 4 through a pipeline, and a second heat exchange medium inlet of the second-effect evaporator 3 is connected to a top gas outlet of the third-effect flash tank 4.3 through a pipeline; a second-effect flash tank 3.3 is connected to a second heat exchange medium outlet of the second-effect evaporator 3 through a pipeline, and a second heat exchange medium inlet of the first-effect evaporator 2 is connected to a top gas outlet of the second-effect flash tank 3.3 through a pipeline; a first-effect flash tank 2.3 is connected to a second heat exchange medium outlet of the first-effect evaporator 2 through a pipeline.

[0026] Top gas outlets of the first-effect flash tank 2.3, the second-effect flash tank 3.3 and the third-effect flash tank 4.3 are all connected to a second vapor discharge pipe 7 through pipelines, and a vapor discharge cooler 7.1 is connected to the second vapor discharge pipe 7; bottom liquid outlets of the first-effect flash tank 2.3, the second-effect flash tank 3.3 and the third-effect flash tank 4.3 are all connected to a flash liquid pipe 8 through pipelines; both the second vapor discharge pipe 7 and the flash liquid pipe 8 are connected to a liquid storage tank 9, and a liquid discharge pump 12 is connected to the liquid storage tank 9.

[0027] A top gas outlet of the stripping column 1 is connected to a condenser 1.1 through a pipeline, and the condenser 1.1 is connected to a chromatograph 1.2 through a pipeline; a bottom liquid outlet of the chromatograph 1.2 is connected to an oil-phase centrifugal pump 1.3 and an aqueous-phase centrifugal pump 1.4 through pipelines, the oil-phase centrifugal pump 1.3 is connected to an oil-phase recovery tank 1.5 through a pipeline, and the aqueous-phase centrifugal pump 1.4 is connected to an aqueous-phase recovery tank 1.6 through a pipeline.

[0028] Top gas outlets of the first-effect evaporator 2, the second-effect evaporator 3, the third-effect evaporator 4 and the chromatograph 1.2 are all connected to a first vapor discharge pipe 6 through pipelines, a vacuum pump 6.1 is connected to the first vapor discharge pipe 6, and the first vapor discharge pipe 6 is connected to the liquid storage tank 9.

[0029] Example 1 of the treatment method for wastewater containing high-boiling-point organic substances

[0030] A treatment method for wastewater containing high-boiling-point organic substances, using the above-mentioned wastewater treatment system containing high-boiling-point organic substances, includes the following steps:

[0031] S1. Feed the wastewater containing high-boiling organic substances into the stripping column 1. The composition of the wastewater containing high-boiling organic substances includes: water, methanol, isobutyraldehyde, trimethylamine, and neopentyl glycol. Among them, the mass percentage of water is 87.1% - 90%, and the mass percentage of neopentyl glycol is 8.9% - 11.4%. Control the pressure inside the stripping column 1 to be 4.5 kPa, and control the temperature of the wastewater inside the stripping column 1 to be 90 °C. Let the vast majority of light-component organic substances and part of the water be discharged from the top of the column. The light-component organic substances include methanol, isobutyraldehyde, and trimethylamine. After discharge, enter the chromatograph 1.2 to separate the light-component organic substances and water, and then recover them.

[0032] S2. The concentrated liquid at the bottom of the stripping column 1 successively enters the first-effect evaporator 2, the second-effect evaporator 3, and the third-effect evaporator 4 to evaporate water. Control the pressure of the first-effect evaporator 2 to be -48 kPa and the temperature to be 82 °C; control the pressure of the second-effect evaporator 3 to be 12 kPa and the temperature to be 102.5 °C; control the pressure of the third-effect evaporator 4 to be 58 kPa and the temperature to be 121.2 °C. The final concentrated liquid is discharged from the third-effect evaporator. The final concentrated liquid is an aqueous solution of neopentyl glycol containing a very small amount of light-component organic substances, and the mass percentage of neopentyl glycol in the aqueous solution of neopentyl glycol is 60% - 65%.

[0033] Example 2 of the treatment method for wastewater containing high-boiling organic substances

[0034] A treatment method for wastewater containing high-boiling organic substances, using the above-mentioned treatment system for wastewater containing high-boiling organic substances, includes the following steps:

[0035] S1. Feed the wastewater containing high-boiling organic substances into the stripping column 1. The composition of the wastewater containing high-boiling organic substances includes: water, methanol, isobutyraldehyde, trimethylamine, and neopentyl glycol. Among them, the mass percentage of water is 87.1% - 90%, and the mass percentage of neopentyl glycol is 8.9% - 11.4%. Control the pressure inside the stripping column 1 to be 3.5 kPa, and control the temperature of the wastewater inside the stripping column 1 to be 85 °C. Let the vast majority of light-component organic substances and part of the water be discharged from the top of the column. The light-component organic substances include methanol, isobutyraldehyde, and trimethylamine. After discharge, enter the chromatograph 1.2 to separate the light-component organic substances and water, and then recover them.

[0036] S2. The concentrated liquid at the bottom of the stripping column 1 successively enters the first-effect evaporator 2, the second-effect evaporator 3, and the third-effect evaporator 4 to evaporate water. Control the pressure of the first-effect evaporator 2 to be -46 kPa and the temperature to be 82.5 °C; control the pressure of the second-effect evaporator 3 to be 10 kPa and the temperature to be 100.8 °C; control the pressure of the third-effect evaporator 4 to be 55 kPa and the temperature to be 120.7 °C. The final concentrated liquid is discharged from the third-effect evaporator. The final concentrated liquid is an aqueous solution of neopentyl glycol containing a very small amount of light-component organic substances, and the mass percentage of neopentyl glycol in the aqueous solution of neopentyl glycol is 60% - 65%.

[0037] Example 3 of the Wastewater Treatment Method Containing High-Boiling Organics

[0038] A wastewater treatment method containing high-boiling organics, using the above-mentioned wastewater treatment system containing high-boiling organics, includes the following steps:

[0039] S1. Feed the wastewater containing high-boiling organics into the stripping tower 1. The composition of the wastewater containing high-boiling organics includes water, methanol, isobutyraldehyde, trimethylamine, and neopentyl glycol. Among them, the mass percentage of water is 87.1% - 90%, and the mass percentage of neopentyl glycol is 8.9% - 11.4%. Control the pressure in the stripping tower 1 to be 3.8 kPa, and control the temperature of the wastewater in the stripping tower 1 to be 86.8 °C. Let the vast majority of light-component organics and part of the water be discharged from the top of the tower. The light-component organics include methanol, isobutyraldehyde, and trimethylamine. After being discharged, enter the chromatograph 1.2 to separate the light-component organics and water, and then recover them.

[0040] S2. The concentrated liquid at the bottom of the stripping tower 1 successively enters the first-effect evaporator 2, the second-effect evaporator 3, and the third-effect evaporator 4 to evaporate water. Control the pressure of the first-effect evaporator 2 to be -47 kPa and the temperature to be 82.8 °C; control the pressure of the second-effect evaporator 3 to be 10.5 kPa and the temperature to be 100.9 °C; control the pressure of the third-effect evaporator 4 to be 53 kPa and the temperature to be 120.1 °C. The final concentrated liquid is discharged from the third-effect evaporator. The final concentrated liquid is an aqueous solution of neopentyl glycol containing a very small amount of light-component organics, and the mass percentage of neopentyl glycol in the aqueous solution of neopentyl glycol is 60% - 65%.

[0041] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wastewater treatment system containing high-boiling organic substances, comprising a stripping column (1), characterized in that, The feed inlet of the stripping column (1) is connected to the wastewater feed pipe (11). The bottom liquid outlet of the stripping column (1) is connected to the first-effect evaporator (2) through a pipeline. The first-effect evaporator (2) is connected to the second-effect evaporator (3) through a pipeline. The second-effect evaporator (3) is connected to the third-effect evaporator (4) through a pipeline. The second-effect evaporator (3) is used to receive the evaporation concentrate of the first-effect evaporator (2), and the third-effect evaporator (4) is used to receive the evaporation concentrate of the second-effect evaporator (3).

2. The wastewater treatment system containing high-boiling organic substances as described in claim 1, characterized in that, An first-effect circulation pipe is connected between the first heat exchange medium inlet and the first heat exchange medium outlet of the first-effect evaporator (2). An first-effect gas-liquid separation tank (2.1) and an first-effect circulation pump (2.2) are connected to the first-effect circulation pipe. A second-effect circulation pipe is connected between the first heat exchange medium inlet and the first heat exchange medium outlet of the second-effect evaporator (3). A second-effect gas-liquid separation tank (3.1) and a second-effect circulation pump (3.2) are connected to the second-effect circulation pipe. A third-effect circulation pipe is connected between the first heat exchange medium inlet and the first heat exchange medium outlet of the third-effect evaporator (4). A third-effect gas-liquid separation tank (4.1), a third-effect circulation pump (4.2) and a discharge pipe (10) are connected to the third-effect circulation pipe.

3. The high-boiling organic compound-containing wastewater treatment system according to claim 2, wherein The second heat exchange medium inlet of the third-effect evaporator (4) is connected to a steam inlet pipe (5). The second heat exchange medium outlet of the third-effect evaporator (4) is connected to a third-effect flash tank (4.3) through a pipeline. The top gas outlet of the third-effect flash tank (4.3) is connected to the second heat exchange medium inlet of the second-effect evaporator (3) through a pipeline. The second heat exchange medium outlet of the second-effect evaporator (3) is connected to a second-effect flash tank (3.3) through a pipeline. The top gas outlet of the second-effect flash tank (3.3) is connected to the second heat exchange medium inlet of the first-effect evaporator (2) through a pipeline. The second heat exchange medium outlet of the first-effect evaporator (2) is connected to a first-effect flash tank (2.3) through a pipeline.

4. The wastewater treatment system containing high-boiling organic substances according to claim 3, characterized in that, The top gas outlets of the first-effect flash tank (2.3), the second-effect flash tank (3.3) and the third-effect flash tank (4.3) are all connected to a second vapor discharge pipe (7) through pipelines. A vapor discharge cooler (7.1) is connected to the second vapor discharge pipe (7). The bottom liquid outlets of the first-effect flash tank (2.3), the second-effect flash tank (3.3) and the third-effect flash tank (4.3) are all connected to a flash liquid pipe (8) through pipelines. The second vapor discharge pipe (7) and the flash liquid pipe (8) are both connected to a storage tank (9), and the storage tank (9) is connected to a liquid discharge pump (12).

5. The high-boiling organic compound-containing wastewater treatment system according to claim 1, wherein The top gas outlet of the stripping column (1) is connected to a condenser (1.1) through a pipeline. The condenser (1.1) is connected to a chromatograph (1.2) through a pipeline. The bottom liquid outlet of the chromatograph (1.2) is connected to an oil-phase centrifugal pump (1.3) and a water-phase centrifugal pump (1.4) through pipelines. The oil-phase centrifugal pump (1.3) is connected to an oil-phase recovery tank (1.5) through a pipeline. The water-phase centrifugal pump (1.4) is connected to a water-phase recovery tank (1.6) through a pipeline.

6. The wastewater treatment system containing high-boiling organic substances according to claim 5, characterized in that, The top air outlets of the first-effect evaporator (2), the second-effect evaporator (3), the third-effect evaporator (4) and the chromatograph (1.2) are all connected with a first vapor discharge pipe (6) through pipelines. A vacuum pump (6.1) is connected to the first vapor discharge pipe (6), and the first vapor discharge pipe (6) is connected to a liquid storage tank (9).

7. The wastewater treatment system containing high-boiling organic substances as described in claim 1, characterized in that, The bottom of the stripping column (1) is connected with a reboiler (1.7), and a first-effect feed pump (1.8) and a preheater (1.9) are connected to the pipeline between the stripping column (1) and the first-effect evaporator (2).

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