PET plastic product cleaning water treatment system
By adopting pre-treatment, AAO treatment and MBR membrane pool treatment methods in the PET plastic product cleaning water treatment system, the problem of difficulty in effectively treating cleaning water in the prior art is solved, and efficient utilization and cost control of water resources are achieved.
Patent Information
- Application Number
- CN202421253478.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-03
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-06-03
AI Technical Summary
The prior art is difficult to effectively treat PET plastic cleaning water while controlling the treatment cost and improve the utilization rate of water resources.
Using a system including a pretreatment system, an AAO treatment system and an MBR membrane cell, some COD and SS are removed through pretreatment, AAO treatment further removes COD, and MBR membrane cell treatment removes a variety of contaminants, and finally the treated moisture is Coarse filtered water and refined filtered water are used for different purposes.
It realizes efficient treatment of cleaning water under the premise of controlling treatment costs, improves the utilization rate of water resources, and reduces the cost of water treatment.
Smart Images
Figure CN222476390U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of sewage treatment, and in particular relates to a PET plastic product washing water treatment system. Background Art
[0002] For reasons of environmental protection and cost control, the raw materials of existing PET plastic products are generally discarded PET plastic bottles. In order to improve the purity of the raw materials, the discarded PET plastic bottles need to be cleaned during the crushing process. Since the discarded PET plastic bottles come from a wide range of sources and have various previous contents, the wastewater after cleaning contains a variety of impurities and cannot be discharged directly. It needs to be purified to meet the discharge standards before it can be discharged.
[0003] However, directly discharging the treated wastewater after it reaches the standard is too wasteful of water resources. Therefore, how to treat the cleaning water and improve the utilization rate of water resources under the premise of effectively controlling the treatment cost has become an urgent problem to be solved in this field. Utility Model Content
[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a PET plastic product washing water treatment system for solving the technical problem of how to treat washing water and improve water resource utilization under the premise of effectively controlling treatment costs.
[0005] The utility model solves the above technical problems with the following technical solutions: A PET plastic product washing water treatment system, comprising:
[0006] A pre-treatment system, the pre-treatment system is used to store and preliminarily treat the cleaning water;
[0007] An AAO treatment system, wherein the water inlet of the AAO treatment system is connected to the water outlet of the pre-treatment system;
[0008] The MBR membrane pool has a water inlet connected to a water outlet of the AAO treatment system, and a coarse filtration water pipeline and a fine filtration water pipeline are arranged at the water outlet of the MBR membrane pool.
[0009] The utility model processes the washing water after washing the discarded PET plastic bottles through a pre-treatment system and an AAO treatment system successively, and then utilizes an MBR membrane pool for treatment. Then, according to the actual use demand of water resources, the washing water treated by the MBR membrane pool is divided into two paths. The coarse filtered water is used to continue washing the discarded PET plastic bottles, and the fine filtered water is used as cooling circulating water for equipment such as injection molding machines. In this way, not only can water resources be reused, but also the washing water used for washing the discarded PET plastic bottles has a low cleanliness requirement, does not need fine filtration treatment, and can reduce the cost of water treatment.
[0010] Further: the pre-treatment system comprises a cleaning water collection tank, a drum microfilter, a pH reaction tank, an air flotation system and a primary sedimentation tank which are connected in sequence, and the water outlet of the primary sedimentation tank is connected to the AAO treatment system;
[0011] The sludge outlet end of the primary sedimentation tank is connected to a sludge tank, and the sludge tank is connected to a sludge dewatering system.
[0012] The beneficial effects of this step are as follows: the pre-treatment system can remove a small amount of COD in the cleaning water, and most of the SS and petroleum pollutants can be removed. Only TDS pollutants are difficult to remove.
[0013] Furthermore: the AAO treatment system comprises an anaerobic tank, an anaerobic tank, an aerobic tank and a final sedimentation tank which are connected in sequence, and the water outlet of the final sedimentation tank is connected to the water inlet of the MBR membrane tank.
[0014] The beneficial effect of adopting this step: AAO can remove most of the COD in the cleaning water.
[0015] Furthermore: the final sedimentation tank and the MBR membrane tank are both provided with pipelines bypassing the anaerobic tank.
[0016] The beneficial effect of adopting this step is that the cleaning water that does not meet the standards in the final sedimentation tank and the MBR membrane tank can re-enter the anaerobic tank through the bypass pipeline and be repeatedly purified.
[0017] Further: the coarse filtered water pipeline includes a sand carbon filter tank, an activated carbon adsorption tank, an ultraviolet disinfector and a reuse water pool A which are connected in sequence;
[0018] The fine filtered water pipeline includes an ultrafiltration system, an RO system and a reuse water pool B which are connected in sequence.
[0019] The beneficial effects of this step are as follows: the operation and maintenance cost of the coarse filtration water pipeline is low, and the effluent quality is low, but it meets the requirements for washing discarded PET plastic bottles. The operation and maintenance cost of the fine filtration water pipeline is high, and the effluent quality is high, which can be used for circulating cooling water of the equipment. Both take into account practicality and economy, and differentiate the water treated by the MBR membrane pool to achieve cost control and improve water resource utilization.
[0020] Furthermore: the RO system is also connected to a discharge tank.
[0021] Beneficial effects of this step: Waste generated by the RO system is collected in the discharge pool and treated uniformly.
[0022] The beneficial effects of the utility model are:
[0023] The cleaning water after washing the discarded PET plastic bottles is pre-treated, AAO treated and MBR membrane pool treated. Then, according to the quality requirements of the water used, the water treated by the MBR membrane pool is divided into two paths, one for coarse filtration water and the other for fine filtration water. In this way, the water treated by the MBR membrane pool does not need to be completely finely filtered. Under the premise of being able to control the cost of purified water, water resources can be reasonably used and the utilization rate of water resources can be improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0025] Figure 1 The utility model provides a work flow chart of a PET plastic product cleaning water treatment system.
[0026] Reference numerals:
[0027] 1-pretreatment system; 2-AAO treatment system; 3-MBR membrane pool; 4-fine filtration water pipeline; 5-coarse filtration water pipeline;
[0028] 11-cleaning water collection tank; 12-drum microfilter; 13-PH reaction tank; 14-flotation system; 15-primary sedimentation tank; 21-anaerobic tank; 22-anaerobic tank; 23-aerobic tank; 24-final sedimentation tank; 41-ultrafiltration system; 42-RO system; 51-sand carbon filter tank; 52-activated carbon adsorption tank; 53-ultraviolet disinfector. DETAILED DESCRIPTION
[0029] The following embodiments of the technical solution of the utility model are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.
[0030] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which the utility model belongs.
[0031] In the description of the present application, 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 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, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0032] In addition, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present utility model, the meaning of "plurality" is more than two, unless otherwise clearly and specifically limited.
[0033] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.
[0034] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0035] Example
[0036] like Figure 1 As shown, the utility model provides a PET plastic product cleaning water treatment system, comprising:
[0037] A pre-treatment system 1, wherein the pre-treatment system 1 is used for storing and preliminarily treating cleaning water;
[0038] AAO treatment system 2, the water inlet end of the AAO treatment system 2 is connected to the water outlet end of the pre-treatment system 1;
[0039] The MBR membrane pool 3 has a water inlet connected to a water outlet of the AAO treatment system 2 , and a coarse filtration water pipeline 5 and a fine filtration water pipeline 4 are provided at the water outlet of the MBR membrane pool 3 .
[0040] The utility model processes the washing water after washing the discarded PET plastic bottles through a pre-treatment system 1 and an AAO treatment system 2, and then processes it through an MBR membrane pool 3. Then, according to the actual use demand of water resources, the washing water processed by the MBR membrane pool 3 is divided into two paths, the coarsely filtered water is used to continue washing the discarded PET plastic bottles, and the finely filtered water is used as cooling circulating water for equipment such as injection molding machines. In this way, not only can water resources be reused, but also the washing water used for washing the discarded PET plastic bottles has a low cleanliness requirement, does not need fine filtration treatment, and can reduce the cost of water treatment.
[0041] On the basis of the above technical solution, the pre-treatment system 1 includes a cleaning water collection tank 11, a drum microfilter 12, a PH reaction tank 13, an air flotation system 14 and a primary sedimentation tank 15 which are connected in sequence, and the outlet end of the primary sedimentation tank 15 is connected to the AAO treatment system 2;
[0042] The sludge outlet end of the primary sedimentation tank 15 is connected to a sludge tank, and the sludge tank is connected to a sludge dewatering system, which includes a filter press and the like.
[0043] Among them, the cleaning water collection tank 11 is used to store cleaning water. Most of the SS (suspended solids) can be removed through centrifugal filtration by the drum microfilter 12. A small amount of COD (chemical oxygen demand) in the cleaning water can be removed through chemical reaction in the PH reaction tank 13, and SS in the cleaning water can be further removed. Most of the petroleum pollutants are removed through the flotation system 13 (the specific technology is recorded in the patent with application number 2006101124365, named Pressure Vessel Flotation System). Only TDS pollutants are difficult to remove.
[0044] On the basis of the above technical solution, the AAO treatment system 2 includes an anaerobic tank 21, an anaerobic tank 22, an aerobic tank 23 and a final sedimentation tank 24 which are connected in sequence, and the outlet end of the final sedimentation tank 24 is connected to the inlet end of the MBR membrane tank 3.
[0045] Specific:
[0046] 1. Principle of anaerobic denitrification in anaerobic tank 21:
[0047] (1) Ammoniation reaction: organic nitrogen compounds are decomposed and converted into ammoniacal nitrogen under the action of ammonifying bacteria;
[0048] (2) Nitrification reaction: Under the action of nitrifying bacteria, ammonia nitrogen is further decomposed and oxidized. This is divided into two stages. In the first stage, under the action of nitrifying bacteria, ammonia (NH+4) is converted into nitrite nitrogen. In the second stage, nitrite nitrogen is further converted into nitrate nitrogen under the action of nitrifying bacteria.
[0049] (3) Denitrification reaction refers to the process in which nitrate nitrogen and nitrite nitrogen are reduced to gaseous nitrogen under the action of denitrifying bacteria.
[0050] After the hydrolysis and acidification treatment, the macromolecular organic matter in the wastewater is removed and decomposed to a large extent. In the hydrolysis and acidification zone, the long-chain organic matter of the macromolecular is broken by facultative bacteria, and decomposed into small-molecule organic matter that is easily biodegradable. The wastewater after hydrolysis and acidification flows into the anoxic zone and the aerobic zone in turn, and a reflux is set in the aerobic zone to the anoxic zone. After the metabolism of the domesticated nitrification and denitrification bacteria, the easily degradable organic matter in the wastewater is decomposed into carbon dioxide and water, and the ammonia nitrogen is converted into nitrogen gas.
[0051] 2. Oxygen pool 22
[0052] This section mainly carries out biological denitrification, which includes two processes: nitrification and denitrification.
[0053] The nitrification process is the conversion of ammonia nitrogen into nitrate nitrogen under the action of nitrifying bacteria.
[0054] The denitrification process is the reduction of nitrate nitrogen and nitrite nitrogen into nitrogen gas under the action of denitrifying bacteria. Nitrifying bacteria are chemoautotrophic bacteria, and their physiological activities do not require organic nutrients. They obtain carbon sources from carbon dioxide and energy from the oxidation of inorganic substances.
[0055] Denitrifying bacteria use the oxygen in nitrate and nitrite ions to breathe in the absence of molecular oxygen to reduce nitrate. The denitrification process is to reduce nitrate nitrogen and nitrite nitrogen to nitrogen gas under the action of denitrifying bacteria. Denitrifying bacteria are heterotrophic facultative anaerobic bacteria. They can only use the oxygen in nitrate and nitrite ions to breathe in the absence of molecular oxygen to reduce nitrate. The main function of the anoxic zone is to carry out the denitrification process.
[0056] At the same time, the circulating mixed liquid in the aerobic tank flows back to the anoxic zone, and the denitrifying bacteria in the return sludge use the organic matter in the sewage as a carbon source to reduce a large amount of nitrate nitrogen in the return mixed liquid into nitrogen gas, thereby achieving the purpose of denitrification.
[0057] The anaerobic hydrolysis digestate is subjected to anoxic aeration before entering the aerobic activated sludge treatment process. During the anoxic process, the dissolved oxygen is controlled below 0.5 mg / L. Facultative denitrifying bacteria use the COD in the influent as a hydrogen donor to reduce the nitrate and nitrite in the mixed liquor of the aerobic tank into nitrogen gas and discharge it into the atmosphere. At the same time, the acid production process in the anaerobic biological treatment reaction process is used to decompose some complex large-molecular polycyclic compounds into low-molecular organic matter.
[0058] 3. Aerobic pool 23
[0059] The mixed liquid enters the aerobic reaction zone from the anoxic reaction zone. This reaction zone unit is multifunctional. BOD5 removal, nitrification and phosphorus absorption reactions are all carried out in this reactor. These three reactions are all important. The mixed liquid contains NO3-N, the sludge contains excess phosphorus, and the BOD5 in the sewage is removed. The mixed liquid of the aerobic tank is returned to the anoxic reactor at 200% of the original sewage volume.
[0060] The main function of the aerobic pool is to remove the residual organic matter in the sewage through aerobic biochemical processes, further degrade COD, and convert ammonia nitrogen into nitrates through the nitrification process. The organic matter in the sewage is oxidized and decomposed by the aerobic absorption and anaerobic release of phosphorus by polyphosphate bacteria (small Gram-negative short rods). At the same time, the phosphorus in the sewage is stored in the bacteria in the form of polyphosphate to form high-phosphorus sludge, which is discharged through the residual sludge, with a good phosphorus removal effect.
[0061] The AAO treatment system 2 can remove most of the COD in the wash water.
[0062] On the basis of the above technical solution, the final sedimentation tank 24 and the MBR membrane tank 3 are both provided with pipelines bypassing the anaerobic tank 21 .
[0063] The cleaning water that does not meet the standards in the final sedimentation tank 24 and the MBR membrane tank 3 can re-enter the anaerobic tank 21 through the bypass pipeline and be repeatedly purified.
[0064] On the basis of the above technical solution, the coarse filtered water pipeline 5 includes a sand carbon filter tank 51, an activated carbon adsorption tank 52, an ultraviolet disinfector 53 and a reuse water pool A which are connected in sequence;
[0065] The fine filtration water pipeline 4 includes an ultrafiltration system 41 (a membrane separation technology that can purify and separate solutions. The ultrafiltration membrane system is a solution separation device that uses ultrafiltration membrane fibers as filtration media and the pressure difference on both sides of the membrane as a driving force. The ultrafiltration membrane only allows the solvent (such as water molecules), inorganic salts and small molecular organic matter in the solution to pass through, while intercepting macromolecular substances such as suspended matter, colloids, proteins and microorganisms in the solution, thereby achieving the purpose of purification or separation), an RO system 42 (reverse osmosis) and a reuse water pool B that are connected in sequence.
[0066] The coarse filtration water pipeline 5 has low operation and maintenance costs, and the effluent quality is low, but it meets the requirements for washing discarded PET plastic bottles. The fine filtration water pipeline 4 has high operation and maintenance costs, and the effluent quality is high, which can be used for circulating cooling water of the equipment. Both take into account practicality and economy, and differentiate and treat the water treated by the MBR membrane pool 3 to achieve cost control and improve water resource utilization.
[0067] On the basis of the above technical solution, the RO system 42 is also connected to a discharge tank.
[0068] The waste generated by the RO system 42 is collected in the discharge pool for unified treatment.
[0069] The following lists the water quality of cleaning water, discharge pool water, reuse water A and reuse water B through multiple tables:
[0070]
[0071] Table 1 Cleaning water quality
[0072]
[0073] Table 2 Discharge pool water quality
[0074]
[0075] Table 3 Recycled water quality
[0076] The effect table of each part of a PET plastic product washing water treatment system provided by this application on the treatment of washing water is as follows:
[0077]
[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.
Claims
1. A PET plastic product cleaning water treatment system, characterized in that: include: A pre-treatment system, the pre-treatment system is used to store and preliminarily treat the cleaning water; An AAO treatment system, wherein the water inlet of the AAO treatment system is connected to the water outlet of the pre-treatment system; The MBR membrane pool has a water inlet connected to a water outlet of the AAO treatment system, and a coarse filtration water pipeline and a fine filtration water pipeline are arranged at the water outlet of the MBR membrane pool.
2. The PET plastic product cleaning water treatment system according to claim 1, characterized in that: The pre-treatment system includes a cleaning water collection tank, a drum microfilter, a pH reaction tank, an air flotation system and a primary sedimentation tank which are connected in sequence, and the water outlet of the primary sedimentation tank is connected to the AAO treatment system; The sludge outlet end of the primary sedimentation tank is connected to a sludge tank, and the sludge tank is connected to a sludge dewatering system.
3. The PET plastic product cleaning water treatment system according to claim 2, characterized in that: The AAO treatment system comprises an anaerobic tank, an anaerobic tank, an aerobic tank and a final sedimentation tank which are connected in sequence, and the water outlet of the final sedimentation tank is connected to the water inlet of the MBR membrane tank.
4. The PET plastic product washing water treatment system according to claim 3, characterized in that: The final sedimentation tank and the MBR membrane tank are both provided with pipelines bypassing the anaerobic tank.
5. The PET plastic product cleaning water treatment system according to claim 1, characterized in that: The coarse filtered water pipeline includes a sand carbon filter tank, an activated carbon adsorption tank, an ultraviolet disinfector and a reuse water pool A which are connected in sequence; The fine filtered water pipeline includes an ultrafiltration system, an RO system and a reuse water pool B which are connected in sequence.
6. The PET plastic product washing water treatment system according to claim 5, characterized in that: The RO system is also connected to a discharge tank.