Multi-stage purified water treatment and zero discharge system

Abstract

The invention discloses a multi-stage purified water treatment and zero discharge system, which comprises a system main body, the system main body comprises a countercurrent gradient washing module, a multi-stage filtration and purification module, an evaporation and crystallization module and an intelligent control platform, the countercurrent gradient washing module is used for countercurrent water supplement, the multi-stage filtration and purification module is used for multi-stage filtration, and the evaporation and crystallization module is used for evaporation and crystallization; the evaporative crystallization module is used for evaporative crystallization, and the intelligent control platform is used for controlling the countercurrent gradient washing module, the multi-stage filtering and purifying module and the evaporative crystallization module. The invention provides a multi-stage purified water treatment and zero discharge system. A countercurrent gradient washing module is used for countercurrent water replenishing, a multi-stage filtering and purifying module is used for multi-stage filtering, and an evaporative crystallization module is used for evaporative crystallization. By means of the structure, the pollutant removal efficiency can be improved, and the device is suitable for most pollutants; the water resource utilization rate can be improved, the wastewater treatment cost is reduced, and the environmental protection pressure is reduced.

Description

Technical Field

[0001] The present invention relates to the field of environmental protection technology and industrial water treatment technology, and more particularly to a multi-stage water purification and zero-discharge system. Background Art

[0002] In industries such as metal processing, automotive painting, and electronic electroplating, pre-treatment water washing processes consume significant amounts of water to remove grease, particles, and chemical residues from workpiece surfaces. Traditional water washing systems commonly suffer from the following issues: high water consumption: a single automotive painting line can consume tens of thousands of tons of water annually, with water resource utilization rates less than 30%; high wastewater treatment costs: wastewater containing oil, heavy metals, and high salinity requires multiple treatment steps, with operational and maintenance costs accounting for over 15% of total costs; and environmental pressures: wastewater discharge faces stringent regulatory restrictions.

[0003] Therefore, it is necessary to propose a multi-stage purified water treatment and zero discharge system to at least partially solve the problems existing in the prior art. Summary of the Invention

[0004] The Summary of the Invention introduces a series of simplified concepts that will be further described in the Detailed Description of the Invention. The Summary of the Invention is not intended to limit the key features and essential features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] In order to at least partially solve the above problems, the present invention provides a multi-stage purified water treatment and zero-discharge system, including: a system body, the system body including a countercurrent gradient water washing module, a multi-stage filtration and purification module, an evaporation and crystallization module and an intelligent control platform, the countercurrent gradient water washing module is used for countercurrent water replenishment, the multi-stage filtration and purification module is used for multi-stage filtration, the evaporation and crystallization module is used for evaporation and crystallization, and the intelligent control platform is used to control the countercurrent gradient water washing module, the multi-stage filtration and purification module, and the evaporation and crystallization module.

[0006] According to the multi-stage purified water treatment and zero-discharge system of an embodiment of the present invention, the countercurrent gradient water washing module includes a pre-wash tank, a main wash tank, and a final wash tank, and the pre-wash tank, the main wash tank, and the final wash tank are connected in sequence.

[0007] According to the multi-stage purified water treatment and zero-discharge system of an embodiment of the present invention, the multi-stage filtration and purification module includes a first-stage hydrocyclone separation section, a second-stage magnetic filter, a third-stage ceramic membrane ultrafiltration section, and a fourth-stage electrochemical demulsification section, and the first-stage hydrocyclone separation section, the second-stage magnetic filter, the third-stage ceramic membrane ultrafiltration section, and the fourth-stage electrochemical demulsification section are connected in sequence.

[0008] According to the multi-stage water purification and zero-discharge system of an embodiment of the present invention, the three-stage composite ceramic membrane is an Al2O3-ZrO2 composite ceramic membrane, and the surface of the three-stage composite ceramic membrane has a PEG hydrophilic coating.

[0009] According to the multi-stage water purification and zero-discharge system of an embodiment of the present invention, the four-stage electrochemical demulsification section has a three-dimensional porous electrode, and the Ti substrate surface of the three-dimensional porous electrode is coated with a PbO2-SnO2 composite catalytic layer.

[0010] According to the multi-stage purified water treatment and zero-discharge system of an embodiment of the present invention, the process flow of the system body is as follows: workpiece water washing → countercurrent water replenishment → three-stage filtration → evaporation crystallization → water recycling.

[0011] Compared with the prior art, the present invention has at least the following beneficial effects:

[0012] The present invention provides a multi-stage water purification and zero-discharge system, which includes a system body, including a countercurrent gradient water washing module, a multi-stage filtration and purification module, an evaporation and crystallization module, and an intelligent control platform. The countercurrent gradient water washing module is used for countercurrent water replenishment, the multi-stage filtration and purification module is used for multi-stage filtration, and the evaporation and crystallization module is used for evaporation and crystallization. The intelligent control platform is used to control the countercurrent gradient water washing module, the multi-stage filtration and purification module, and the evaporation and crystallization module. This structure can improve the efficiency of pollutant removal and is applicable to most pollutants. It can also improve water resource utilization, reduce wastewater treatment costs, and reduce environmental pressure.

[0013] The multi-stage purified water treatment and zero discharge system described in the present invention, and other advantages, objectives and features of the present invention will be reflected in part through the following description, and in part will be understood by those skilled in the art through research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0015] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments so that those skilled in the art can implement the invention with reference to the description.

[0017] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0018] like Figure 1 As shown, the present invention provides a multi-stage water purification and zero-discharge system, comprising: a system body 100, wherein the system body 100 includes a countercurrent gradient water washing module 1, a multi-stage filtration and purification module 2, an evaporation and crystallization module 3, and an intelligent control platform (not shown). The countercurrent gradient water washing module 1 is used for countercurrent water replenishment, the multi-stage filtration and purification module 2 is used for multi-stage filtration, and the evaporation and crystallization module 3 is used for evaporation and crystallization. The intelligent control platform is used to control the countercurrent gradient water washing module 1, the multi-stage filtration and purification module 2, and the evaporation and crystallization module 3. The above structure can improve the removal efficiency of pollutants and is applicable to most pollutants; it can also improve water resource utilization, reduce wastewater treatment costs, and reduce environmental pressure.

[0019] Specifically, the process flow of the system main body 100 is as follows: workpiece water washing → countercurrent water replenishment → three-stage filtration → evaporation crystallization → water recycling.

[0020] Furthermore, the above-mentioned countercurrent gradient water washing module 1 includes a pre-wash tank 11, a main washing tank 12, and a final washing tank 13. The pre-wash tank 11, the main washing tank 12, and the final washing tank 13 are connected in sequence to form a three-stage series water washing tank, and the final washing tank 13 is replenished with fresh water and overflows in reverse to the main washing tank 12 and the pre-wash tank 11 in the front section; the water-saving mechanism of the above-mentioned three-stage series water washing tank: through the graded utilization of water quality gradient, the water saving rate can be increased to 60% to 70%.

[0021] Furthermore, the multi-stage filtration and purification module 2 includes a first-stage hydrocyclone 21, a second-stage magnetic filter 22, a third-stage ceramic membrane ultrafiltration 23, and a fourth-stage electrochemical demulsification 24, which are sequentially connected. The first-stage hydrocyclone 21 can remove particles > 50 μm with an efficiency > 95%; the second-stage magnetic filter 22 can remove particles > 5 μm, reducing subsequent membrane contamination; and the third-stage composite ceramic membrane 23 is an Al2O3-ZrO2 composite ceramic membrane with a PEG hydrophilic coating on the surface of the Al2O3-ZrO2 matrix, a pore size of 0.1 μm, and acid and alkali resistance of pH 2 to 12.

[0022] Furthermore, the above-mentioned four-stage electrochemical demulsification section 24 has a three-dimensional porous electrode, and the duty cycle of the pulse current when in use is 30% to 50%; and the Ti substrate surface of the three-dimensional porous electrode is coated with a PbO2-SnO2 composite catalytic layer, so that the demulsification efficiency reaches an emulsified oil removal rate of >98% and COD is reduced by 80% to 90%.

[0023] Furthermore, the steam recompression ratio of the evaporation crystallization module 3 during use is 1:2.5, and the evaporation temperature is 70-90°C; the purity of the crystallized salt in the condensed water returning to the process tank is ≥99.5%; HEDP (hydroxyethylidene diphosphonic acid) is added during scale inhibition to inhibit CaSO4 scaling.

[0024] For example, the present invention is described by taking the sudden increase in the oil content of the wastewater in the pre-wash tank 11 as an example.

[0025] When the oil content of the wastewater in the pre-wash tank 11 increases suddenly, the sensor installed in the pre-wash tank 11 is triggered, that is, the infrared oil analyzer detects that the oil concentration is greater than 100ppm; then the intelligent control platform controls the response and increases the current in the four-stage electrochemical demulsification section 24 to 50mA / cm 2 ; Start the backflush program of the three-stage ceramic membrane ultrafiltration section 23 to prevent oil blockage; adjust the feed pump speed of the evaporation crystallization module 3 to slow down and avoid high-load operation; Results: Within 30 minutes, the oil concentration returned to <20ppm and the system was stable.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 understood as limiting the present invention.

[0027] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0028] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A multi-stage water purification and zero discharge system, characterized in that: include: The system body includes a countercurrent gradient water washing module, a multi-stage filtration and purification module, an evaporation crystallization module and an intelligent control platform. The countercurrent gradient water washing module is used for countercurrent water replenishment, the multi-stage filtration and purification module is used for multi-stage filtration, the evaporation crystallization module is used for evaporation crystallization, and the intelligent control platform is used to control the countercurrent gradient water washing module, the multi-stage filtration and purification module, and the evaporation crystallization module.

2. A multi-stage water purification and zero discharge system according to claim 1, characterized in that: The countercurrent gradient water washing module includes a pre-wash tank, a main wash tank, and a final wash tank, and the pre-wash tank, the main wash tank, and the final wash tank are connected in sequence.

3. A multi-stage water purification and zero discharge system according to claim 1, characterized in that: The multi-stage filtration and purification module includes a first-stage hydrocyclone separation part, a second-stage magnetic filter, a third-stage ceramic membrane ultrafiltration part and a fourth-stage electrochemical demulsification part, and the first-stage hydrocyclone separation part, the second-stage magnetic filter, the third-stage ceramic membrane ultrafiltration part and the fourth-stage electrochemical demulsification part are connected in sequence.

4. A multi-stage water purification and zero discharge system according to claim 3, characterized in that: The three-level composite ceramic membrane is an Al2O3-ZrO2 composite ceramic membrane, and the surface of the three-level composite ceramic membrane has a PEG hydrophilic coating.

5. The multi-stage water purification and zero discharge system according to claim 3, characterized in that: The four-stage electrochemical demulsification part is provided with a three-dimensional porous electrode, and the surface of the Ti substrate of the three-dimensional porous electrode is coated with a PbO2-SnO2 composite catalytic layer.

6. The multi-stage water purification and zero discharge system according to claim 1, characterized in that: The process flow of the main body of the system is as follows: workpiece water washing → countercurrent water replenishment → three-stage filtration → evaporation crystallization → water recycling.

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