A method and system for removing heavy metals based on shunt regulation processing

Abstract

The application discloses a heavy metal removal method and system based on shunt adjustment processing, which comprises the following steps: setting a pH critical value, screening a heavy metal sample to be treated based on the pH critical value; setting a pH adjustment value, a precipitation duration and a product shunt ratio; performing primary cycle precipitation treatment on the screened heavy metal sample to be treated based on the pH adjustment value, the precipitation duration and the product shunt ratio to obtain a primary purification product; setting a flow speed threshold value and a space flow speed threshold value, performing secondary filtration treatment on the primary purification product based on the flow speed threshold value and the space flow speed threshold value to obtain a heavy metal removal finished product; the application can process heavy metal samples in multiple stages, flocculation and precipitation are treated through primary processing shunt cycle processing, reciprocal combination reactions are performed on the flocculation and precipitation, the concentration of the final precipitation product is improved, liquid products after solid-liquid separation are subjected to quartz sand filtration and heavy metal adsorption through secondary processing, and the heavy metal content of the products is strictly controlled.

Description

Technical Field

[0001] This invention relates to the field of heavy metal removal technology, and in particular to a method and system for heavy metal removal based on diversion and regulation. Background Technology

[0002] Current heavy metal removal processes include chemical reagent extraction, microbial rinsing, and flocculation sedimentation. However, these processes are all relatively simple and straightforward, resulting in low removal quality of heavy metals from the treated material. Furthermore, these processes are costly, with expensive raw materials and equipment, making them unsuitable for long-term application.

[0003] In summary, current heavy metal removal processes have high raw material and equipment costs, low heavy metal removal quality, narrow applicability, and low cost-effectiveness. Summary of the Invention

[0004] The present invention mainly addresses the problems of high raw material and equipment costs, low heavy metal removal quality, narrow applicability, and low cost-effectiveness of current heavy metal removal processes.

[0005] To solve the above-mentioned technical problems, one technical solution adopted by the present invention is to provide a method for removing heavy metals based on diversion and regulation treatment, comprising the following steps:

[0006] Sample screening steps:

[0007] Set a pH threshold value, and screen heavy metal samples to be treated based on the pH threshold value;

[0008] Primary purification steps for removing heavy metals:

[0009] Set the pH adjustment value, precipitation time, and product split ratio; based on the pH adjustment value, precipitation time, and product split ratio, perform a primary circulating precipitation treatment on the screened heavy metal samples to be treated to obtain a primary purified product;

[0010] Secondary purification steps for removing heavy metals:

[0011] Set a flow velocity threshold and a spatial flow velocity threshold, and perform secondary filtration on the primary purification product based on the flow velocity threshold and the spatial flow velocity threshold to obtain a finished product with heavy metals removed.

[0012] As an improved solution, the primary circulating precipitation treatment includes: step one, step two, and step three performed sequentially;

[0013] Step one includes: performing a sequential reaction step on the screened heavy metal samples to be treated based on the pH adjustment value to obtain samples to be flocculated;

[0014] Step two includes: performing flocculation and precipitation treatment on the sample to be flocculated according to the precipitation time to obtain heavy metal precipitation products;

[0015] Step three includes: adjusting the flow of the heavy metal precipitate based on the product split ratio to obtain the primary purified product.

[0016] As an improved solution, the pH adjustment value includes: a first adjustment value range and a second adjustment value range;

[0017] The sequential reaction steps include:

[0018] Set a first interval, place the heavy metal sample to be treated into a first adjustment container, and add a first adjustment reagent to the first adjustment container every first interval until the pH value of the heavy metal sample to be treated in the first adjustment container is within the first adjustment value range.

[0019] When the pH value of the heavy metal sample to be treated is within the first adjustment range, the heavy metal sample to be treated in the first adjustment container is extracted into the second adjustment container, and a second adjustment reagent is added to the second adjustment container until the pH value of the heavy metal sample to be treated in the second adjustment container is within the second adjustment range.

[0020] The heavy metal sample to be treated, whose pH value is within the second adjustment range, is extracted as the sample to be flocculated.

[0021] As an improved solution, the flocculation and sedimentation treatment includes:

[0022] The sample to be flocculated is treated with aluminum salt or iron salt as a flocculant to obtain a sample to be precipitated; the sample to be precipitated is placed in a precipitation container for precipitation for a duration equal to the precipitation time to obtain the heavy metal precipitate.

[0023] As an improved solution, the shunt regulation process includes:

[0024] Set the second interval duration, sludge discharge volume, and volume threshold;

[0025] Every second interval, a sludge discharge and diversion step is performed on the heavy metal precipitate according to the sludge discharge volume and the product diversion ratio;

[0026] After each sludge discharge and diversion step, the first volume value of the heavy metal precipitate in the sedimentation container is measured; the first volume value is compared with the volume threshold. If the threshold is reached, the heavy metal precipitate in the sedimentation container is subjected to solid-liquid separation treatment; the liquid product after solid-liquid separation treatment is extracted as the primary purification product.

[0027] As an improved solution, the sludge discharge and diversion step includes: a sludge discharge step and a diversion step performed sequentially;

[0028] The sludge removal step includes: discharging the heavy metal precipitate product corresponding to the sludge removal amount from the sedimentation container outside the sedimentation container;

[0029] The diversion step includes: dividing the heavy metal precipitate in the precipitation container into a first precipitate to be adjusted and a second precipitate to be adjusted according to the product diversion ratio; extracting the first precipitate to be adjusted into the first adjustment container and extracting the second precipitate to be adjusted into the third reaction container; adding NaOH solution to the third reaction container until the pH value of the second precipitate to be adjusted in the third reaction container reaches a first target value; after the pH value of the second precipitate to be adjusted reaches the first target value, extracting both the first precipitate to be adjusted in the first adjustment container and the second precipitate to be adjusted in the third reaction container into the second adjustment container for reaction to obtain the diversion adjustment product; and returning the diversion adjustment product as the sample to be flocculated to step two of the primary circulating precipitation treatment.

[0030] As an improved solution, the secondary filtration process includes:

[0031] A first acidic regulator is added to the primary purified product until the pH value of the primary purified product reaches the second target value.

[0032] The primary purified product with a pH value reaching the second target value is filtered by a quartz sand filter with a flow velocity not greater than the flow velocity threshold to obtain a secondary purified product.

[0033] The secondary purification product is subjected to heavy metal adsorption treatment using a heavy metal resin tower with a spatial flow velocity not exceeding the spatial flow velocity threshold, to obtain the heavy metal-free finished product.

[0034] As an improved approach, the first adjustment value range is: pH 3.5 to pH 4.5;

[0035] The second adjustment range is: pH 8 to pH 9.5;

[0036] The first target value is: pH value 10;

[0037] The second target value is: pH 7;

[0038] The product split ratio corresponding to the first precipitate to be adjusted and the second precipitate to be adjusted is 1:2;

[0039] Both the first regulating reagent and the second regulating reagent include calcium oxide.

[0040] As an improved solution, the diversion step further includes:

[0041] When the first precipitate to be adjusted is extracted into the first adjustment container, the first adjustment reagent is added to the first adjustment container every first interval until the pH value of the first precipitate to be adjusted in the first adjustment container is within the first adjustment value range.

[0042] When the first precipitate to be adjusted in the first adjustment container and the second precipitate to be adjusted in the third reaction container are both extracted into the second adjustment container, the second adjustment reagent is added to the second adjustment container until the pH value of the reaction product of the first precipitate to be adjusted and the second precipitate to be adjusted in the second adjustment container is within the second adjustment value range.

[0043] The present invention also provides a heavy metal removal system based on diversion regulation, comprising:

[0044] The sample screening module is used to set the pH critical value and screen heavy metal samples to be treated based on the pH critical value.

[0045] The primary purification module is used to set the pH adjustment value, precipitation time, and product split ratio; based on the pH adjustment value, precipitation time, and product split ratio, the screened heavy metal samples to be treated undergo primary circulating precipitation treatment to obtain primary purified products.

[0046] The secondary purification module is used to set the flow velocity threshold and the spatial flow velocity threshold, and to perform secondary filtration on the primary purification product based on the flow velocity threshold and the spatial flow velocity threshold to obtain a finished product with heavy metals removed.

[0047] The beneficial effects of this invention are:

[0048] 1. The heavy metal removal method based on diversion and regulation treatment described in this invention can achieve multi-stage treatment of samples containing heavy metals. The first stage treatment is based on the design of diversion and circulation treatment for flocculation and precipitation, which carries out repeated chemical reactions on the flocculated precipitate, thereby increasing the concentration of the final precipitate product. This is more conducive to the removal of heavy metals from the product during solid-liquid separation in the final precipitation container. The second stage treatment performs quartz sand filtration and heavy metal adsorption on the liquid product after solid-liquid separation, further reducing the heavy metal content in the liquid product, thereby further improving the quality of heavy metal removal. This strictly controls the heavy metal content of the product. The whole method has high cost-effectiveness, low operating cost, and extremely high applicability, making up for the shortcomings of the prior art.

[0049] 2. The heavy metal removal system based on diversion and regulation processing described in this invention can achieve the heavy metal removal method based on diversion and regulation processing described in this invention through the cooperation of sample screening module, primary purification module and secondary purification module. It can then process samples containing heavy metals in a multi-stage manner, and the multi-stage processing continuously improves the quality of heavy metal removal, thereby strictly controlling the heavy metal content of the product. It has low operating cost and extremely high applicability, making up for the shortcomings of the prior art. Attached Figure Description

[0050] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0051] Figure 1 This is a flowchart of the heavy metal removal method based on diversion and regulation processing described in Embodiment 1 of the present invention;

[0052] Figure 2 This is a schematic diagram of the specific process of the heavy metal removal method based on diversion and regulation as described in Embodiment 1 of the present invention;

[0053] Figure 3 This is an architecture diagram of the heavy metal removal system based on diversion and regulation processing described in Embodiment 2 of the present invention. Detailed Implementation

[0054] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0055] In the description of this invention, it should be noted that the embodiments described in this invention are only some embodiments of this invention, not all embodiments; based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0056] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0057] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "pH critical value," "heavy metal sample to be treated," "pH adjustment value," "precipitation time," "product split ratio," "primary circulating precipitation treatment," "flow velocity threshold," "spatial flow velocity threshold," "secondary filtration treatment," "sequential reaction step," "flocculation precipitation treatment," "heavy metal precipitation product," "split adjustment treatment," "sludge discharge and splitting step," "solid-liquid separation treatment," "liquid product," "acidic regulator," "quartz sand filtration," "heavy metal adsorption treatment," "sample screening module," "primary purification module," and "secondary purification module" should be interpreted broadly. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0058] Example 1

[0059] This embodiment provides a method for removing heavy metals based on diversion and regulation processing, such as... Figure 1 and Figure 2 As shown, it includes the following steps:

[0060] S100, Sample screening steps, specifically including:

[0061] S110. Set a pH threshold value and screen heavy metal samples to be treated based on the pH threshold value;

[0062] Specifically, in this embodiment, the pH threshold is set to 2. In this embodiment, samples with a pH value less than 2 are selected as the heavy metal samples to be treated; the heavy metal samples to be treated are usually electroplating wastewater.

[0063] S200, the first-stage purification process for removing heavy metals, specifically includes:

[0064] S210. Set the pH adjustment value, precipitation time and product split ratio; based on the pH adjustment value, precipitation time and product split ratio, perform primary circulating precipitation treatment on the screened heavy metal samples to be treated to obtain primary purified products.

[0065] Specifically, the primary circulating precipitation treatment includes: steps one, two, and three performed sequentially; specifically, in this embodiment, the pH adjustment value includes: a first adjustment value range and a second adjustment value range; the first adjustment value range is: pH 3.5 to pH 4.5; the second adjustment value range is: pH 8 to pH 9.5; the precipitation time is 10 min, and the product split ratio is 1:2;

[0066] Specifically, step one includes: performing a sequential reaction step on the screened heavy metal samples to be treated based on the pH adjustment value to obtain a sample to be flocculated; the sequential reaction step involves using two reaction vessels to sequentially adjust the pH value of the initial heavy metal samples to be treated, thereby uniformly, efficiently and effectively adjusting the pH value.

[0067] Specifically, step two includes: performing flocculation and precipitation treatment on the sample to be flocculated according to the precipitation time to obtain heavy metal precipitation products; step two mainly involves performing flocculation and precipitation treatment on the sample after adjusting the pH value to precipitate impurities in the wastewater.

[0068] Specifically, step three includes: adjusting the flow of the heavy metal precipitate based on the product flow ratio to obtain the primary purified product; the flow adjustment process is the core of the primary treatment process of this method, used to reduce the difficulty of heavy metal removal and improve the quality of heavy metal removal.

[0069] Specifically, the sequential reaction steps include:

[0070] A first interval is set, and the heavy metal sample to be treated is placed in a first adjustment container. A first adjustment reagent is added to the first adjustment container every first interval until the pH value of the heavy metal sample in the first adjustment container is within the first adjustment value range. Specifically, the first interval is set according to a specific pH adjustment method; in this embodiment, the first interval is 10 seconds. Correspondingly, the first adjustment container is a pH adjustment container equipped with a stirring device to improve pH stirring efficiency. When the pH value of the heavy metal sample to be treated is within the first adjustment value range, then... The acidity of the heavy metal sample to be treated has been further reduced, so further adjustment steps can be performed. Therefore, the heavy metal sample to be treated in the first adjustment container is extracted into the second adjustment container, and a second adjustment reagent is added to the second adjustment container until the pH value of the heavy metal sample to be treated in the second adjustment container is within the second adjustment value range. In this embodiment, the second adjustment container is a conical reaction vessel, which is also equipped with a stirring device to improve the reaction efficiency. After this, the heavy metal sample to be treated with a pH value within the second adjustment value range is extracted as the sample to be flocculated.

[0071] Specifically, in this embodiment, both the first regulating reagent and the second regulating reagent include calcium oxide (i.e., CaO).

[0072] Specifically, the flocculation and precipitation treatment includes: using aluminum salt or iron salt as a flocculant to flocculate the sample to be flocculated to obtain a sample to be precipitated; placing the sample to be precipitated into a precipitation container for precipitation for a duration equal to the precipitation duration to obtain the heavy metal precipitation product; the heavy metal precipitation product is a solid-liquid mixed compound, wherein the solid compound is the precipitated impurity;

[0073] Specifically, the diversion adjustment process includes: setting a second interval duration, sludge discharge amount, and volume threshold; in this embodiment, the second interval duration is 15 seconds, which provides time for volume measurement of the heavy metal precipitate in the sedimentation container; the sludge discharge amount is set according to the specific situation, and in this embodiment, the sludge discharge amount is set to 8%~10% of the total amount of heavy metal precipitate in the sedimentation container; the volume threshold is set according to the internal volume of the sedimentation container, and in this embodiment, it is set to 2 / 3 of the sedimentation container volume; every second interval duration, a sludge discharge and diversion step is performed on the heavy metal precipitate according to the sludge discharge amount and the product diversion ratio. Step; after each sludge discharge and diversion step, i.e., within the second time interval, the first volume value of the heavy metal precipitate in the sedimentation container is measured; compare whether the first volume value reaches the volume threshold. If it does, it means that the precipitate has reached a certain size and cannot be further diverted. Therefore, the heavy metal precipitate in the sedimentation container is subjected to solid-liquid separation treatment; the liquid product after solid-liquid separation treatment is extracted as the primary purification product, i.e., sedimentation permeate; if it does not reach the threshold, the sludge discharge and diversion step is performed on the heavy metal precipitate every second time interval according to the sludge discharge amount and the product diversion ratio.

[0074] Specifically, the sludge discharge and diversion step includes: a sludge discharge step and a diversion step performed sequentially; the sludge discharge step includes: discharging the heavy metal precipitate corresponding to the sludge discharge volume from the sedimentation container to prepare for diversion treatment; the diversion step includes: dividing the heavy metal precipitate in the sedimentation container into a first precipitate to be adjusted and a second precipitate to be adjusted according to the product diversion ratio; in this embodiment, the product diversion ratio is the first precipitate to be adjusted: the second precipitate to be adjusted = 1:2; therefore, the first precipitate to be adjusted is extracted into the first adjustment container, and the second precipitate to be adjusted is extracted into the third reaction container; when the second precipitate to be adjusted is extracted into the third reaction container, NaOH solution is added to the third reaction container until the pH value of the second precipitate to be adjusted in the third reaction container reaches the first pH value. The target value is: pH 10. The third reaction vessel is a chemical reaction vessel, and the running time of the chemical reaction vessel is 2-3 minutes. When the pH value of the second precipitate to be adjusted reaches the first target value, the first precipitate to be adjusted in the first adjustment vessel and the second precipitate to be adjusted in the third reaction vessel are both extracted into the second adjustment vessel for reaction to obtain a split adjustment product. The split adjustment product is returned to step two of the first-stage circulating sedimentation treatment as the sample to be flocculated, that is, flocculation and sedimentation are carried out again, and this process is repeated. Correspondingly, the purpose of this step is to repeatedly adjust the precipitate in the reaction sedimentation vessel. On the one hand, the precipitate is subjected to repeated chemical reactions to improve the flocculation quality of the final precipitate. On the other hand, it is beneficial to improve the removal quality of heavy metals and improve the water quality of the liquid product after solid-liquid separation.

[0075] Specifically, the diversion step further includes: when the first precipitate to be adjusted is extracted into the first adjustment container, the first adjustment reagent is added to the first adjustment container at first intervals until the pH value of the first precipitate to be adjusted in the first adjustment container is within the first adjustment value range; when both the first precipitate to be adjusted in the first adjustment container and the second precipitate to be adjusted in the third reaction container are extracted into the second adjustment container, the second adjustment reagent is added to the second adjustment container until the pH value of the reaction product of the first precipitate to be adjusted and the second precipitate to be adjusted in the second adjustment container is within the second adjustment value range; that is, when the first precipitate to be adjusted and the second precipitate to be adjusted return to their respective first and second adjustment containers, the relevant pH adjustment operation in the sequential reaction step is performed again to improve the precipitation quality of the precipitate and facilitate re-flocculation in the reciprocating process.

[0076] S300, the secondary purification process for removing heavy metals specifically includes:

[0077] S310. Set a flow velocity threshold and a spatial flow velocity threshold, and perform secondary filtration on the primary purification product based on the flow velocity threshold and the spatial flow velocity threshold to obtain a heavy metal-free finished product. In this embodiment, the secondary purification heavy metal removal step is to further ensure the quality of heavy metal removal. Correspondingly, for example, in electroplating represented by nickel, even after alkaline flocculation and precipitation, under the action of heavy metal capture agents, the heavy metal content of the primary purification product, i.e., the precipitated water, is generally between 0.3 and 0.5 mg / L, which still cannot guarantee to meet the GB electroplating table three standard of less than 0.1 mg / L. Therefore, further heavy metal removal treatment is required.

[0078] Specifically, the secondary filtration process includes:

[0079] A first acidic adjuster is added to the primary purified product until the pH value of the primary purified product reaches a second target value; specifically, the second target value is pH 7. After adjustment, the primary purified product with the pH value reaching the second target value is filtered through a quartz sand filter at a flow rate not exceeding the flow rate threshold to obtain a secondary purified product. Specifically, quartz sand filtration can trap some suspended metal particles in the primary purified product, further reducing the heavy metal concentration. Then, the secondary purified product is subjected to heavy metal adsorption treatment through a heavy metal resin tower at a spatial flow rate not exceeding the spatial flow rate threshold to obtain the heavy metal-free finished product. Correspondingly, the heavy metal resin tower can ensure that the content of heavy metal ions in the treated secondary purified product is less than 0.02 mg / L, until the content of heavy metal ions in the secondary purified product is less than 0.01 mg / L. In this embodiment, the flow rate threshold is 10 m / h, and the spatial flow rate threshold is 30 m / h. 3 / h.

[0080] Example 2

[0081] This embodiment is based on the same inventive concept as the heavy metal removal method based on diversion regulation described in Embodiment 1, and further provides a heavy metal removal system based on diversion regulation, such as... Figure 3 As shown, it includes:

[0082] The sample screening module is used to set the pH critical value and screen heavy metal samples to be treated based on the pH critical value.

[0083] The primary purification module is used to set the pH adjustment value, precipitation time, and product split ratio; based on the pH adjustment value, precipitation time, and product split ratio, the screened heavy metal samples to be treated undergo primary circulating precipitation treatment to obtain primary purified products.

[0084] Specifically, the primary circulating precipitation treatment includes three steps performed sequentially by the primary purification module: Step 1, Step 2, and Step 3; Step 1 includes: the primary purification module performs a sequential reaction step on the screened heavy metal samples to be treated based on the pH adjustment value to obtain samples to be flocculated; Step 2 includes: the primary purification module performs flocculation and precipitation treatment on the samples to be flocculated according to the precipitation time to obtain heavy metal precipitation products; Step 3 includes: the primary purification module performs diversion adjustment treatment on the heavy metal precipitation products based on the product diversion ratio to obtain the primary purified product.

[0085] Specifically, the pH adjustment value includes: a first adjustment value range and a second adjustment value range;

[0086] Specifically, the sequential reaction steps include: a primary purification module sets a first interval; the primary purification module places the heavy metal sample to be treated into a first adjustment container; the primary purification module adds a first adjustment reagent to the first adjustment container every first interval until the pH value of the heavy metal sample to be treated in the first adjustment container is within the first adjustment value range; when the pH value of the heavy metal sample to be treated is within the first adjustment value range, the primary purification module extracts the heavy metal sample to be treated from the first adjustment container into a second adjustment container and adds a second adjustment reagent to the second adjustment container until the pH value of the heavy metal sample to be treated in the second adjustment container is within the second adjustment value range; the primary purification module extracts the heavy metal sample to be treated whose pH value is within the second adjustment value range as the flocculation sample.

[0087] Specifically, the flocculation and precipitation treatment includes: the primary purification module uses aluminum salt or iron salt as a flocculant to flocculate the sample to be flocculated to obtain a sample to be precipitated; the primary purification module places the sample to be precipitated into a precipitation container for precipitation treatment for a duration equal to the precipitation time to obtain the heavy metal precipitate product.

[0088] Specifically, the diversion and adjustment process includes: the primary purification module setting a second interval duration, sludge discharge volume, and volume threshold; the primary purification module performing a sludge discharge and diversion step on the heavy metal precipitate product every second interval duration according to the sludge discharge volume and the product diversion ratio; after each sludge discharge and diversion step, the primary purification module measuring a first volume value of the heavy metal precipitate product in the precipitation container; the primary purification module comparing whether the first volume value reaches the volume threshold, and if it does, the primary purification module performing solid-liquid separation treatment on the heavy metal precipitate product in the precipitation container; and the primary purification module extracting the liquid product after solid-liquid separation treatment as the primary purification product.

[0089] Specifically, the sludge discharge and diversion step includes: the primary purification module sequentially executing the sludge discharge step and the diversion step; the sludge discharge step includes: the primary purification module discharging the heavy metal precipitate corresponding to the sludge discharge volume from the sedimentation container; the diversion step includes: the primary purification module dividing the heavy metal precipitate in the sedimentation container into a first precipitate to be adjusted and a second precipitate to be adjusted according to the product diversion ratio; the primary purification module extracting the first precipitate to be adjusted into the first adjustment container, and the primary purification module extracting the second precipitate to be adjusted into the third reaction container; the primary purification module adding NaOH solution to the third reaction container until the pH value of the second precipitate to be adjusted in the third reaction container reaches a first target value; when the pH value of the second precipitate to be adjusted reaches the first target value, the primary purification module extracting both the first precipitate to be adjusted in the first adjustment container and the second precipitate to be adjusted in the third reaction container into the second adjustment container for reaction, obtaining the diversion adjustment product; the primary purification module returning the diversion adjustment product as the flocculation sample to step two in the primary circulating sedimentation treatment.

[0090] Specifically, the diversion step further includes: when the first precipitate to be adjusted is extracted into the first adjustment container, the primary purification module adds the first adjustment reagent to the first adjustment container every first interval until the pH value of the first precipitate to be adjusted in the first adjustment container is within the first adjustment value range; when both the first precipitate to be adjusted in the first adjustment container and the second precipitate to be adjusted in the third reaction container are extracted into the second adjustment container, the primary purification module adds the second adjustment reagent to the second adjustment container until the pH value of the reaction product of the first precipitate to be adjusted and the second precipitate to be adjusted in the second adjustment container is within the second adjustment value range;

[0091] The secondary purification module is used to set the flow velocity threshold and the spatial flow velocity threshold, and to perform secondary filtration on the primary purification product based on the flow velocity threshold and the spatial flow velocity threshold to obtain a finished product with heavy metals removed.

[0092] Specifically, the secondary filtration process includes: a secondary purification module adding a first acidic regulator to the primary purification product until the pH value of the primary purification product reaches a second target value; the secondary purification module performing quartz sand filtration on the primary purification product with the pH value reaching the second target value using a quartz sand filter with a flow rate not exceeding the flow rate threshold to obtain a secondary purification product; and the secondary purification module performing heavy metal adsorption treatment on the secondary purification product using a heavy metal resin tower with a spatial flow rate not exceeding the spatial flow rate threshold to obtain the heavy metal-free finished product.

[0093] Specifically, in this embodiment, the sample screening module, primary purification module, and secondary purification module in the heavy metal removal system based on diversion and regulation are all intelligent modules composed of relevant mechanical mechanisms, several electrically controlled regulating containers, electrically controlled reaction containers, electrically controlled flocculation and sedimentation containers, relevant industrial control host equipment, and manual assistance.

[0094] Unlike existing technologies, the heavy metal removal method and system based on diversion and regulation in this application can achieve multi-stage treatment of samples containing heavy metals. The first stage is based on a diversion and circulation flocculation precipitation design, which performs repeated chemical reactions on the flocculated precipitate to increase the concentration of the final precipitate product. This is more conducive to the removal of heavy metals during solid-liquid separation of the product in the final precipitation container. The second stage filters the liquid product after solid-liquid separation with quartz sand and adsorbs heavy metals to further reduce the heavy metal content in the liquid product, thereby further improving the quality of heavy metal removal and strictly controlling the heavy metal content of the product. This application has high cost-effectiveness, low operating cost, and extremely high applicability, making up for the shortcomings of existing technologies.

[0095] The embodiment numbers disclosed in the above embodiments of the present invention are merely for description and do not represent the superiority or inferiority of the embodiments.

[0096] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for removing heavy metals based on diversion and regulation, characterized in that, Includes the following steps: Sample screening steps: Set a pH threshold value, and screen heavy metal samples to be treated based on the pH threshold value; Primary purification steps for removing heavy metals: Set the pH adjustment value, precipitation time, and product split ratio; based on the pH adjustment value, precipitation time, and product split ratio, perform a primary circulating precipitation treatment on the screened heavy metal samples to be treated to obtain a primary purified product; The primary circulating sedimentation process includes: step one, step two, and step three performed sequentially; Step one includes: performing a sequential reaction step on the screened heavy metal samples to be treated based on the pH adjustment value to obtain samples to be flocculated; Step two includes: performing flocculation and precipitation treatment on the sample to be flocculated according to the precipitation time to obtain heavy metal precipitation products; Step three includes: adjusting the flow of the heavy metal precipitate based on the product split ratio to obtain the primary purified product; Secondary purification steps for removing heavy metals: Set a flow velocity threshold and a spatial flow velocity threshold, and perform secondary filtration on the primary purification product based on the flow velocity threshold and the spatial flow velocity threshold to obtain a finished product with heavy metals removed; The diversion and adjustment process includes: setting a second interval duration, sludge discharge volume, and volume threshold; and performing a sludge discharge and diversion step on the heavy metal precipitate product every second interval duration according to the sludge discharge volume and the product diversion ratio. The sludge discharge and diversion step includes: a sludge discharge step and a diversion step performed sequentially; the diversion step includes: dividing the heavy metal precipitate in the sedimentation container into a first precipitate to be regulated and a second precipitate to be regulated according to the product diversion ratio; extracting the first precipitate to be regulated into a first regulating container, and extracting the second precipitate to be regulated into a third reaction container; adding NaOH solution to the third reaction container until the pH value of the second precipitate to be regulated in the third reaction container reaches a first target value; after the pH value of the second precipitate to be regulated reaches the first target value, extracting both the first precipitate to be regulated in the first regulating container and the second precipitate to be regulated in the third reaction container into a second regulating container for reaction to obtain a diversion adjustment product; and returning the diversion adjustment product as the flocculation sample to step two of the primary circulating sedimentation treatment.

2. The method for removing heavy metals based on diversion and regulation processing according to claim 1, characterized in that: The pH adjustment value includes: a first adjustment value range and a second adjustment value range; The sequential reaction steps include: Set a first interval, place the heavy metal sample to be treated into a first adjustment container, and add a first adjustment reagent to the first adjustment container every first interval until the pH value of the heavy metal sample to be treated in the first adjustment container is within the first adjustment value range. When the pH value of the heavy metal sample to be treated is within the first adjustment range, the heavy metal sample to be treated in the first adjustment container is extracted into the second adjustment container, and a second adjustment reagent is added to the second adjustment container until the pH value of the heavy metal sample to be treated in the second adjustment container is within the second adjustment range. The heavy metal sample to be treated, whose pH value is within the second adjustment range, is extracted as the sample to be flocculated.

3. The method for removing heavy metals based on diversion and regulation processing according to claim 2, characterized in that: The flocculation and sedimentation treatment includes: The sample to be flocculated is treated with aluminum salt or iron salt as a flocculant to obtain a sample to be precipitated; the sample to be precipitated is placed in a precipitation container for precipitation for a duration equal to the precipitation time to obtain the heavy metal precipitate.

4. The method for removing heavy metals based on diversion and regulation processing according to claim 3, characterized in that: The diversion and regulation process also includes: After each sludge discharge and diversion step, the first volume value of the heavy metal precipitate in the sedimentation container is measured; the first volume value is compared with the volume threshold. If the threshold is reached, the heavy metal precipitate in the sedimentation container is subjected to solid-liquid separation treatment; the liquid product after solid-liquid separation treatment is extracted as the primary purification product.

5. The method for removing heavy metals based on diversion and regulation processing according to claim 4, characterized in that: The sludge removal step includes: discharging the heavy metal precipitate corresponding to the sludge removal amount from the sedimentation container outside the sedimentation container.

6. The method for removing heavy metals based on diversion and regulation processing according to claim 5, characterized in that: The secondary filtration process includes: A first acidic regulator is added to the primary purified product until the pH value of the primary purified product reaches the second target value. The primary purified product with a pH value reaching the second target value is filtered by a quartz sand filter with a flow velocity not greater than the flow velocity threshold to obtain a secondary purified product. The secondary purification product is subjected to heavy metal adsorption treatment using a heavy metal resin tower with a spatial flow velocity not exceeding the spatial flow velocity threshold, to obtain the heavy metal-free finished product.

7. The method for removing heavy metals based on diversion and regulation processing according to claim 6, characterized in that: The first adjustment range is: pH 3.5 to pH 4.5; The second adjustment range is: pH 8 to pH 9.5; The first target value is: pH value 10; The second target value is: pH 7; The product split ratio corresponding to the first precipitate to be adjusted and the second precipitate to be adjusted is 1:2; Both the first regulating reagent and the second regulating reagent include calcium oxide.

8. The method for removing heavy metals based on diversion and regulation processing according to claim 7, characterized in that: The diversion step further includes: When the first precipitate to be adjusted is extracted into the first adjustment container, the first adjustment reagent is added to the first adjustment container every first interval until the pH value of the first precipitate to be adjusted in the first adjustment container is within the first adjustment value range. When the first precipitate to be adjusted in the first adjustment container and the second precipitate to be adjusted in the third reaction container are both extracted into the second adjustment container, the second adjustment reagent is added to the second adjustment container until the pH value of the reaction product of the first precipitate to be adjusted and the second precipitate to be adjusted in the second adjustment container is within the second adjustment value range.

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