Release agent purification and recovery treatment system and method

Abstract

The invention discloses a release agent purification and recovery treatment system and method, and belongs to the technical field of die-casting wastewater treatment. A release agent purification and recovery treatment system comprises a wastewater collection pool and a treatment module, and the treatment module comprises a pre-filter connected with the wastewater collection pool; the paper tape filter is connected with the pre-filter; the treatment tank is connected with the paper tape filter and is used for storing filtrate filtered by the paper tape filter; the treatment tank is connected with the hydrodynamic cavitation device; a slag scraping mechanism is arranged above the treatment tank; the slag receiving tank is arranged on one side of the treatment tank and is positioned below the slag scraping mechanism; a liquid inlet pump is arranged between the pre-filter and the paper tape filter; and the treatment tank is provided with a clean liquid port. The invention provides a release agent purification and recovery treatment system which can effectively treat waste wax, floating oil and solid small particles in release agent wastewater and is compact in equipment structure.

Description

Technical Field

[0001] The invention relates to the technical field of die-casting wastewater treatment, and in particular to the field of a release agent purification and recovery treatment system. Background Art

[0002] The purification treatment of release agent is different from that of cutting fluid. The waste cutting fluid is generally recycled and purified at the bottom of the machine tool tank. After filtering and removing particulate matter, the cutting fluid can be directly returned to the top of the machine tool for use. The reuse rate of cutting fluid is relatively high. However, the use of release agent is one-time. Once the release agent is used in the die-casting process of the die-casting machine, it becomes waste liquid. Generally speaking, all waste liquid will enter the ditch of the die-casting workshop, be collected, and be treated centrally. At present, most die-casting workshops use sewage treatment methods to degrade the harmful components of the waste release agent liquid so that it can meet the emission requirements and be directly discharged into nature, which has a high treatment cost.

[0003] Because the release agent in die-casting production is a one-time agent and the loss of the release agent is large, in order to ensure the normal operation of die-casting production, it is necessary to continuously add the original liquid to configure new release agent for production, resulting in a large amount of waste liquid in the die-casting workshop, and high environmental protection treatment costs and pressure. Therefore, it is necessary to purify and reuse the release agent wastewater to reduce the use of the release agent original liquid and reduce the die-casting cost of the die-casting workshop. Release agent waste liquid often has problems such as microbial growth leading to odor, high content of solid wax and particulate matter, and mixing with miscellaneous oil after production.

[0004] At present, some enterprises use recycling equipment to purify the release agent and reuse it. The treatment method is to remove oil and then filter it in multiple stages. However, wax has the property of being deformable. If it is filtered with a filter element, the wax cannot be filtered out under the pressure of the inlet liquid, but will pass through the gaps in the filter bag or filter cloth. Because the solid wax is not completely removed from the release agent after multi-stage filtration, it will affect the die-casting quality of the workpiece, and cause problems such as blackening of the workpiece and even sticking to the mold and stripping of the mold.

[0005] Another method is to first precipitate and degrease the waste liquid, then flotate the degreased liquid, and remove the solid wax floating on the liquid surface through a wax remover. Flotation brings fine particles and solid wax and other impurities in the release agent waste liquid to the liquid surface through bubbles, but a lot of oil or wax in the liquid exists in the form of water-in-oil or oil-in-water. Simple flotation cannot completely remove the wax or oil in it. The oil is easy to breed bacteria. If it is used again on the die-casting equipment, it will make the die-casting workpiece black and affect the die-casting quality.

[0006] Some current treatment methods have poor release agent treatment effects and low treatment efficiency, and the pipeline connections are complicated and the equipment is bulky. Summary of the invention

[0007] In order to solve the above problems of existing release agent purification and recovery treatment, the present invention provides a release agent purification and recovery treatment system, which can effectively treat waste wax and floating oil in release agent wastewater, and the equipment structure is compact.

[0008] Based on the above problems, the solution is as follows:

[0009] A release agent purification and recovery system includes a wastewater collection tank and a processing module; the processing module includes:

[0010] A pre-filter connected to the wastewater collection tank;

[0011] A paper belt filter connected to the pre-filter;

[0012] A treatment tank connected to the paper belt filter and used to store the filtrate filtered by the paper belt filter; the treatment tank is connected to the hydraulic cavitation generating device; a scraping mechanism is provided above the treatment tank;

[0013] A slag receiving trough, which is arranged at one side of the treatment tank and is located below the slag scraping mechanism;

[0014] A liquid inlet pump is provided between the pre-filter and the paper belt filter;

[0015] The treatment pool is provided with a clean liquid outlet.

[0016] Preferably, the cavitation generating device includes a hemispherical container, a plurality of guide blades are provided in the hemispherical container, a liquid inlet is provided on the top of the hemispherical container, the cavitation generating device also includes a liquid outlet pipe inserted into the hemispherical container, a porous plate is provided in the liquid outlet pipe, the liquid outlet pipe is spaced a certain distance from the bottom of the hemispherical container, and an outwardly protruding inlet is provided on the lower side of the liquid outlet pipe.

[0017] Preferably, an air inlet pipe extending into the container and passing through the porous plate is provided at the bottom of the hemispherical container, and the air inlet pipe allows gas to enter the cavitation generating device. The inlet end of the air inlet pipe is the negative pressure port of the cavitation generating device; the negative pressure port is connected to a negative pressure gauge and a one-way valve.

[0018] Preferably, outside the treatment tank, the liquid inlet of the cavitation generating device is connected to a high-pressure pump, the upstream of the high-pressure pump is connected to the treatment tank, the liquid outlet pipe of the cavitation generating device is connected to the treatment tank, and a positive pressure gauge is connected between the cavitation generating device and the high-pressure pump.

[0019] Preferably, an ozone aeration head is provided in the treatment tank, and the ozone aeration head is connected to an ozone generator;

[0020] Alternatively, the negative pressure port of the cavitation generating device is connected to an ozone generator.

[0021] Preferably, the scraping mechanism comprises: a scraping plate and a driving assembly, wherein the driving assembly drives the scraping plate to scrape the scum on the surface of the treatment pool to the scum receiving groove.

[0022] Preferably, a baffle is provided between the treatment pool and the slag receiving trough, and a slag guiding portion inclined toward the slag receiving trough is provided above the baffle.

[0023] Preferably, a partition is provided in the slag receiving trough, and the partition divides the slag receiving trough into a slag trough and a waste liquid trough; a U-shaped pipe is provided between the slag trough and the waste liquid trough.

[0024] Preferably, an inclined surface is provided at the bottom of the slag trough, and a slag outlet is provided at the lower end of the inclined surface.

[0025] Preferably, the slag outlet is connected to a waste slag collecting device, and a slag extraction pump is connected between the slag outlet and the waste slag collecting device.

[0026] Preferably, the waste liquid tank is provided with a circulation loop connected to the upstream of the liquid inlet pump, and the circulation loop is connected between the pre-filter and the liquid inlet pump through a three-way valve.

[0027] Preferably, the clean liquid port is connected to a clean liquid pool, a precision filter is connected between the clean liquid port and the clean liquid pool, and a liquid outlet pump is connected between the clean liquid port and the precision filter.

[0028] According to the release agent purification and recovery treatment system, the present invention also provides a release agent purification and recovery treatment method, the treatment method comprises the following steps;

[0029] S1. The release agent wastewater is introduced from the wastewater collection tank through the liquid inlet pump, filtered by the pre-filter, and then filtered by the paper belt filter to the treatment tank to fill the treatment tank;

[0030] S2. Hydrodynamic cavitation treatment is carried out in the treatment tank, and ozone is introduced at the same time. The floating oil, waste wax and small solid particles in the wastewater float on the surface of the treatment tank, and the upper suspended matter is scraped out by the scraping mechanism;

[0031] S3, the scraped suspended matter with liquid enters the scum tank, and when the liquid level of the scum tank rises to the highest height of the U-shaped tube, the lower layer of waste liquid is introduced into the waste liquid tank, and the upper layer of suspended matter continues to stay in the scum tank, thereby achieving the separation of suspended matter and liquid;

[0032] S4, the waste liquid in the waste liquid tank passes through the circulation loop, is filtered by the paper belt filter, and is introduced into the treatment tank again to replenish the liquid level that drops after the scraping mechanism is operated;

[0033] S5. After multiple cycles of treatment, the treatment liquid in the treatment tank is introduced into a precision filter to further filter out a small amount of wax residue and then discharged into a clean liquid tank or recycled for formulation.

[0034] Further, in S2, ozone is introduced into the treatment tank or ozone is inhaled through the negative pressure port of the cavitation generator.

[0035] Further, in S3, the concentrated floating oil, waste wax, and solid small particles in the scum tank are pumped to a waste residue collection device by a slag pumping pump.

[0036] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0037] 1. The nanoscale bubbles generated by the hydrodynamic cavitation technology will implode instantaneously to generate a large amount of energy, thereby generating high temperature, high pressure, and micro-jet flow, causing the oil, waste wax, and solid small particles existing in the emulsified system to demulsify, which is beneficial to subsequent scum scraping treatment; flotation can only continuously generate micron-scale bubbles, entraining oil droplets to float, and cannot break the emulsified system formed by the combination of water, oil, wax, and solid small particles.

[0038] 2. The liquid-carrying scum is scraped into the slag receiving tank, and through a U-shaped tube, the bottom layer of waste liquid is introduced into the waste liquid tank, so that relatively dry, thick floating oil, waste wax, and solid small particles are continuously accumulated in the scum tank; the bottom of the scum tank is inclined, and the scum can flow from one end to the other end, and finally is pumped out to the waste residue collection device by a slag pumping pump; the separation of liquid and scum of the liquid-carrying scum can be realized, improving the solid waste collection rate and the waste liquid recycling rate.

[0039] 3. The waste liquid in the waste liquid tank is pumped back to the paper belt filter again. At this time, the waste liquid is relatively clean because most of the waste residue has been separated. Compared with the method of directly separating the waste liquid and waste residue through the paper belt filter, the loss of the paper belt of the paper belt filter is reduced, saving consumables.

[0040] 4. Combining ozone with hydrodynamic cavitation, while performing hydrodynamic cavitation treatment, ozone is introduced into the treatment tank. The cavitation effect can accelerate the decomposition of O 3 so that more OH· is generated by the decomposition of ozone in the cavitation bubbles. In addition, the turbulence in the cavitation region increases the mass transfer rate of O 3 in the aqueous phase, and the sterilization effect is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic structural diagram of the treatment system of the present invention.

[0042] Figure 2 It is a schematic structural diagram of the equipment of the treatment system.

[0043] Figure 3 It is a schematic structural diagram of the treatment tank and the scum scraping mechanism.

[0044] Figure 4 This is a cross-sectional view of the treatment tank.

[0045] Figure 5 It is a cross-sectional view of the slag trough.

[0046] Figure 6 It is a cross-sectional view of the center of the cavitation generating device.

[0047] In the figure: wastewater collection tank 1, pre-filter 2, liquid inlet pump 3, paper belt filter 4, treatment tank 5, slag receiving tank 6, scum tank 60, inclined surface 600, slag outlet 601, waste liquid tank 61, baffle 62, slag guide part 620, partition 63, U-shaped tube 64, slag scraping mechanism 7, slag scraping plate 70, power 71, high-pressure pump 8, cavitation generating device 9, positive pressure gauge 90, negative pressure gauge 91, hemispherical container 900, guide vane 901, liquid inlet 902, liquid outlet pipe 903, inlet 9030, porous plate 904, air inlet pipe 905, precision filter 10, slag extraction pump 11, liquid outlet pump 12, ozone generator 13, aeration head 130, three-way valve 14, clean liquid tank 15. DETAILED DESCRIPTION

[0048] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0049] like Figure 1 As shown, a release agent purification and recovery treatment system includes a wastewater collection tank 1, a treatment tank 5, and a clean liquid tank 15. A pre-filter 2 and a paper belt filter 4 are arranged in sequence between the treatment tank 5 and the wastewater collection tank 1, a liquid inlet pump 3 is connected between the pre-filter 2 and the paper belt filter 4, and a three-way valve 14 is connected between the liquid inlet pump 3 and the pre-filter 2.

[0050] like Figure 1-Figure 2 As shown, the paper belt filter 4 is provided with a liquid inlet 40 leading to a treatment tank 5, and the treatment tank 5 is used to store the filtrate filtered by the paper belt filter 4; Figure 1 As shown, the treatment tank 5 is connected to the hydrodynamic cavitation generating device 9, the upstream of the hydrodynamic cavitation generating device 9 is connected to the high-pressure pump 8, the upstream of the high-pressure pump is connected to the treatment tank 5, and the downstream of the hydrodynamic cavitation generating device 9 is connected to the treatment tank 5; a positive pressure gauge 90 is provided between the high-pressure pump 8 and the hydrodynamic cavitation generating device 9, and the hydrodynamic cavitation generating device 9 is provided with a negative pressure port, the negative pressure port is connected to a negative pressure gauge 91, and the negative pressure port is connected to a one-way valve.

[0051] like Figure 4 As shown, an aeration head 130 of an ozone generator 13 is provided in the treatment pool 5, or the ozone generator 13 is connected to the negative pressure port of the cavitation generating device.

[0052] like Figure 6As shown, the cavitation generating device 9 includes a hemispherical container 900, a plurality of guide blades 901 are arranged in the hemispherical container, a liquid inlet 902 is arranged above the hemispherical surface, and the cavitation generating device 9 also includes a liquid outlet pipe 903 inserted into the hemispherical closed container, a porous plate 904 is arranged in the liquid outlet pipe, the liquid outlet pipe 903 is spaced a certain distance from the bottom of the hemispherical container 900, and an outwardly protruding inlet 9030 is arranged at the lower side of the liquid outlet pipe.

[0053] An air inlet pipe 905 extending into the container and passing through the porous plate 904 is provided at the bottom of the hemispherical container 900. The air inlet pipe 905 can introduce gas into the cavitation generating device. The inlet end of the air inlet pipe is the negative pressure port of the cavitation generating device. The negative pressure port is provided with a one-way valve, which is connected to the ozone generating device.

[0054] like Figure 3 , Figure 4 As shown, a scraping mechanism 7 is provided above the treatment tank 5, and the scraping mechanism 7 includes a scraping plate 70 and a power 71. The power 71 drives the driving wheel to rotate, and the driving wheel drives the driven wheel through a transmission belt. The driven wheels are connected to each other through a transmission belt. The scraping plate 70 is arranged on the transmission belt, and the transmission belt drives the scraping plate 70 to scrape the suspended wax residue and part of the waste liquid from one side of the treatment tank 5 to the residue receiving tank 6.

[0055] like Figure 4 As shown, a baffle 62 is provided between the treatment pool 5 and the slag receiving tank 6, and a slag guide portion 620 inclined toward the slag receiving tank 6 is provided on the upper part of the baffle 62. A partition 63 is provided in the slag receiving tank 6, and the partition 63 divides the slag receiving tank 6 into a slag tank 60 and a waste liquid tank 61. A U-shaped pipe 64 is provided in the slag tank 60 and communicated with the waste liquid tank 61. The liquid in the lower layer of the slag tank 60 enters the waste liquid tank 61 through the U-shaped pipe, and the concentrated floating oil, waste wax and small solid particles are retained in the slag tank 60. Figure 5 As shown, an inclined surface 600 is provided at the bottom of the slag trough 60, and a slag outlet 601 is provided at the lower side of the inclined surface. Figure 1 The slag outlet 601 extracts the concentrated floating oil, waste wax and solid small particles to the waste wax collection device through the slag extraction pump 11.

[0056] like Figure 1 As shown, the waste liquid tank 61 is provided with a circulation loop connected to the upstream of the liquid inlet pump 3, and the circulation loop is connected between the pre-filter 2 and the liquid inlet pump 3 through a three-way valve 14, and the three-way valve 14 switches the liquid inlet flow path and the liquid return flow path.

[0057] The treatment pool 5 is also provided with a liquid purification port, which is connected to the liquid purification pool 15 , and a liquid outlet pump 12 and a precision filter 10 are provided between the liquid purification port and the liquid purification pool 15 in sequence.

[0058] Liquid level meters are provided in the wastewater collection tank 1 , the treatment tank 5 , and the waste liquid tank 61 .

[0059] The working principle of the release agent purification and recovery system of the present invention is as follows:

[0060] The three-way valve 14 is switched to the liquid inlet mode, and the release agent wastewater is pumped out from the wastewater collection tank 1 through the liquid inlet pump 3. After being filtered by the pre-filter 2 and the paper belt filter 4, the filtrate enters the treatment tank 5. The treatment tank 5 is subjected to hydraulic cavitation treatment, and ozone is introduced into the treatment tank 5 at the same time. The floating oil, waste wax and small solid particles in the sewage float on the surface of the treatment tank. The upper suspended matter is scraped out to the scum tank 60 by the scraping mechanism 7. When the liquid level of the scum tank reaches the highest height of the U-shaped tube, the lower waste liquid is introduced into the waste liquid tank 61, and the upper suspended matter continues to remain in the scum tank 60; when the waste liquid tank 61 reaches a certain liquid level, the three-way valve 14 is switched to the liquid return mode, and the waste liquid is pumped to the top of the paper belt filter, and is introduced into the treatment tank 5 again after filtration. The sewage in the treatment tank 5 is continuously cavitated and ozone-generated to purify the sewage in the treatment tank. When there is less scum on the surface, the cavitation treatment and ozone-generating are stopped, the inlet pump 3 is turned off, the outlet pump 12 is turned on, and the treated liquid is filtered through a precision filter to remove a small amount of wax scum and discharged to the clean liquid tank 15, or used for release agent mixing and recycling. The concentrated floating oil, wax scum and other solid particles in the scum tank 60 are pumped to the waste scum collection device by the scum pump 11.

[0061] Based on a release agent purification and recycling system, the present invention also provides a release agent purification and recycling method, which comprises the following steps:

[0062] S1. The release agent wastewater is introduced from the wastewater collection tank into the treatment tank through the liquid inlet pump, firstly through the pre-filter for coarse filtration, then through the paper belt filter for fine filtration;

[0063] S2. Hydrodynamic cavitation treatment is carried out in the treatment tank, and ozone is introduced at the same time. Floating oil, waste wax and small solid particles in the wastewater float on the surface of the treatment tank, and the upper suspended matter is scraped out by the scraping mechanism; ozone is introduced into the treatment tank or inhaled through the negative pressure port of the cavitation generating device;

[0064] S3, the scraped suspended matter with liquid enters the scum tank, and when the scum liquid level in the scum tank rises to the highest height of the U-shaped tube, the lower layer of waste liquid is introduced into the waste liquid tank, and the upper layer of suspended matter continues to stay in the scum tank; the waste slag in the scum tank is pumped out to the waste slag collection device by the slag pump at irregular intervals;

[0065] S4, the waste liquid in the waste liquid tank is filtered through a paper belt filter through a circulation loop and introduced into the treatment tank again to replenish the liquid level that drops after the scraping mechanism is operated; it is treated with hydraulic cavitation and ozone again;

[0066] S5. After multiple cycles of treatment, the treated liquid in the treatment tank is introduced into a precision filter to further filter out a small amount of wax residue and then discharged into a clean liquid tank or proportioned for reuse.

[0067] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the present invention to solve basically the same technical problems and achieve basically the same technical effects are all included in the protection scope of the present invention.

Claims

1. A release agent purification and recovery system, comprising a wastewater collection tank and a processing module. It is characterized in that The processing module comprises: A pre-filter connected to the wastewater collection tank; A paper belt filter connected to the pre-filter; A treatment tank connected to the paper belt filter and used to store the filtrate filtered by the paper belt filter; the treatment tank is connected to the hydraulic cavitation generating device; a scraping mechanism is provided above the treatment tank; A slag receiving trough, which is arranged at one side of the treatment tank and is located below the slag scraping mechanism; A liquid inlet pump is provided between the pre-filter and the paper belt filter; The treatment pool is provided with a clean liquid outlet.

2. A release agent purification and recovery system according to claim 1, It is characterized in that The cavitation generating device includes a hemispherical container, a plurality of guide blades are arranged in the hemispherical container, a liquid inlet is arranged on the top of the hemispherical container, the cavitation generating device also includes a liquid outlet pipe inserted into the hemispherical container, a porous plate is arranged in the liquid outlet pipe, a certain distance is left between the liquid outlet pipe and the bottom of the hemispherical container, and an inlet protruding outward is arranged on the lower side of the liquid outlet pipe.

3. A release agent purification and recovery system according to claim 2, It is characterized in that An air inlet pipe extending into the container and penetrating the porous plate is provided at the bottom of the hemispherical container. The air inlet pipe allows gas to enter the cavitation generating device. The inlet end of the air inlet pipe is the negative pressure port of the cavitation generating device. The negative pressure port is connected to a negative pressure gauge and a one-way valve.

4. A release agent purification and recovery system according to claim 1 or 2, It is characterized in that Outside the treatment tank, the liquid inlet of the cavitation generating device is connected to a high-pressure pump, the upstream of the high-pressure pump is connected to the treatment tank, and the liquid outlet pipe of the cavitation generating device is connected to the treatment tank; a positive pressure gauge is connected between the cavitation generating device and the high-pressure pump.

5. A release agent purification and recovery system according to claim 1, It is characterized in that An ozone aeration head is provided in the treatment tank, and the ozone aeration head is connected to an ozone generator; Alternatively, the negative pressure port of the cavitation generating device is connected to an ozone generator.

6. A release agent purification and recovery system according to claim 1, It is characterized in that The scraping mechanism comprises a scraping plate and a driving assembly, wherein the driving assembly drives the scraping plate to scrape the floating scum on the surface of the treatment pool to the scum receiving groove.

7. A release agent purification and recovery system according to claim 1, It is characterized in that A baffle is provided between the treatment pool and the slag receiving trough, and a slag guiding portion inclined toward the slag receiving trough is provided above the baffle.

8. A release agent purification and recovery system according to claim 1, It is characterized in that A partition is provided in the slag receiving trough, and the partition divides the slag receiving trough into a slag trough and a waste liquid trough; a U-shaped pipe is provided between the slag trough and the waste liquid trough.

9. A release agent purification and recovery system according to claim 8, It is characterized in that The bottom of the slag trough is provided with an inclined surface, and a slag outlet is provided at the lower end of the inclined surface.

10. A release agent purification and recovery system according to claim 9, It is characterized in that The slag outlet is connected to a waste slag collecting device, and a slag extraction pump is connected between the slag outlet and the waste slag collecting device.

11. A release agent purification and recovery system according to claim 8, It is characterized in that The waste liquid tank is provided with a circulation loop connected to the upstream of the liquid inlet pump, and the circulation loop is connected between the pre-filter and the liquid inlet pump through a three-way valve.

12. A release agent purification and recovery system according to claim 1, It is characterized in that The clean liquid port is connected to the clean liquid pool, a precision filter is connected between the clean liquid port and the clean liquid pool, and a liquid outlet pump is connected between the clean liquid port and the precision filter.

13. A release agent purification and recovery method according to any one of claims 1 to 12, It is characterized in that The processing method comprises the following steps: S1, the release agent wastewater is introduced from the wastewater collection tank into the treatment tank through the liquid inlet pump, after preliminary filtration by the pre-filter, and then filtered by the paper belt filter; S2. Hydrodynamic cavitation treatment is carried out in the treatment tank, and ozone is introduced at the same time. The floating oil, waste wax and small solid particles in the wastewater float on the surface of the treatment tank, and the upper suspended matter is scraped out by the scraping mechanism; S3, the scraped suspended matter with liquid enters the scum tank, and when the liquid level of the scum tank rises to the highest height of the U-shaped tube, the lower layer of waste liquid is introduced into the waste liquid tank, and the upper layer of suspended matter continues to stay in the scum tank, thereby achieving the separation of suspended matter and liquid; S4, the waste liquid in the waste liquid tank passes through the circulation loop, is filtered by the paper belt filter, and is introduced into the treatment tank again to replenish the liquid level that drops after the scraping mechanism is operated; S5. After multiple cycles of treatment, the treated liquid in the treatment tank is introduced into a precision filter to further filter out a small amount of wax residue and then discharged into a clean liquid tank or proportioned for reuse.

14. A release agent purification and recovery method according to claim 13, It is characterized in that In S2, ozone is introduced into the treatment pool or is sucked in through the negative pressure port of the cavitation generating device.

15. A release agent purification and recovery method according to claim 13, It is characterized in that In S3, the solid small particles such as floating oil and waste wax concentrated in the scum tank are pumped to the waste slag collection device by a slag pump.

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