Photovoltaic sludge dewatering process and system

Abstract

The invention relates to a photovoltaic sludge dewatering process and system. The photovoltaic sludge dewatering process comprises the following steps: S1, conveying photovoltaic sludge to a sludge treatment tank; s2, adjusting the pH value of the photovoltaic sludge in the sludge treatment tank; s3, adding a flocculating agent into the sludge treatment tank to form flocculent sludge; and S4, carrying out filter-pressing dehydration on the photovoltaic sludge in the sludge treatment tank by using a plate-and-frame filter-pressing unit. Through the arrangement, an existing mode that other sludge and photovoltaic sludge are mixed and filter-pressed is changed into a mode that flocculent sludge is produced from the photovoltaic sludge by using the flocculating agent and then is subjected to filter-pressing dehydration by using the plate-and-frame filter-pressing unit, so that the dehydration rate of the photovoltaic sludge is improved, on one hand, the output of sludge residues is reduced, and on the other hand, the energy consumption is reduced; and on the other hand, the decomposition risk of the sludge residues with low water content is reduced, so that the risk of odor and leachate overflow is reduced, and the environmental protection requirement is met.

Description

Technical Field

[0001] The present application relates to the technical field of sludge dehydration, and in particular to a photovoltaic sludge dehydration process and system. Background Art

[0002] The photovoltaic industry or the semiconductor industry generates a large amount of wastewater during the production of silicon wafers, including high-concentration organic wastewater generated during the slicer cutting of raw materials, wastewater generated in the degumming area and cleaning area, workpiece cleaning wastewater, and cutting machine cylinder washing wastewater.

[0003] The system for treating the above wastewater usually adopts A2O (Anaerobic-Anoxic-Oxic, "anaerobic-anoxic-aerobic" sewage treatment process). During the operation of the system, the activated sludge in the aerobic tank is affected by factors such as the incoming water load or unbalanced nutrient ratio, resulting in poor sludge activity. The sludge needs to be dehydrated and discharged.

[0004] Currently, the common way to dehydrate photovoltaic sludge is to use plate and frame filter pressing technology, which is to mix photovoltaic sludge with other sludge without adding chemicals and filter press. However, the water content of photovoltaic sludge after filtration is high and the dehydration rate is low. Summary of the invention

[0005] Based on this, it is necessary to provide a photovoltaic sludge dehydration process and system to address the current problem of low efficiency of photovoltaic sludge dehydration.

[0006] A photovoltaic sludge dehydration process, characterized in that it comprises the following steps:

[0007] S1, transporting photovoltaic sludge to the sludge treatment pool;

[0008] S2. adjusting the pH value of the photovoltaic sludge in the sludge treatment tank;

[0009] S3, adding flocculant to the sludge treatment tank to form flocculent sludge;

[0010] S4. Utilizing a plate and frame filter press unit to filter press and dehydrate the photovoltaic sludge in the sludge treatment tank.

[0011] The photovoltaic sludge dehydration process is as follows: the photovoltaic sludge is transported to the sludge treatment pool to obtain the photovoltaic sludge treatment site through step S1; the pH value of the photovoltaic sludge in the sludge treatment pool is adjusted through step S2, so that the sludge treatment pool has a suitable acid-base environment; after adding flocculant to the sludge treatment pool in step S3, flocculent sludge is formed under a suitable acid-base environment; finally, the photovoltaic sludge in the sludge treatment pool is filtered and dehydrated by a plate and frame filter press unit. Through the above settings, the existing method of mixing other sludges with photovoltaic sludge for filtering is changed to a method of using a flocculant to make photovoltaic sludge produce flocculent sludge and then using a plate and frame filter press unit to filter and dehydrate the flocculent sludge, thereby improving the dehydration rate of photovoltaic sludge. On the one hand, the output of sludge residue is reduced, thereby reducing the subsequent disposal cost of sludge residue and saving storage space for sludge residue. On the other hand, the sludge residue with low water content reduces the risk of decay, thereby reducing the risk of odor and leachate overflow, meeting environmental protection requirements.

[0012] In one embodiment, the plate and frame filter press unit includes a plate and frame filter press and a sludge discharge pump. In step S4, the following steps are specifically included:

[0013] S41, using the sludge discharge pump to pump the photovoltaic sludge in the sludge treatment tank into the plate and frame filter press;

[0014] S42, the plate and frame filter press performs filter pressing and dehydration on the photovoltaic sludge.

[0015] In one embodiment, the filter cloth of the plate and frame filter press has a model of 750B, and the air permeability of the filter cloth is 80L.

[0016] In one embodiment, the flocculant is polyaluminium chloride.

[0017] In one embodiment, in step S2, the following steps are specifically included:

[0018] S21, detecting the pH value of the photovoltaic sludge;

[0019] S22. Using a pH value adjustment unit, add an acidic agent and / or an alkaline agent to the sludge treatment tank to adjust the pH value of the photovoltaic sludge to between 6.8 and 7.2.

[0020] In one embodiment, between step S3 and step S4, the following steps are also included:

[0021] Compressed gas is injected into the sludge treatment tank by using an aeration unit so that the photovoltaic sludge is evenly mixed with the flocculant, the acidic agent, and / or the alkaline agent.

[0022] In one embodiment, step S1 specifically includes the following steps:

[0023] The sludge feed pump pumps the photovoltaic sludge in the secondary sedimentation tank into the sludge treatment tank.

[0024] The present application also provides a photovoltaic sludge dehydration system for implementing the photovoltaic sludge dehydration process described in any of the above embodiments, the photovoltaic sludge dehydration system comprising:

[0025] Sludge treatment pool, used to provide a place for treating photovoltaic sludge;

[0026] A pH value adjustment unit, connected to the sludge treatment tank, for adjusting the pH value of the photovoltaic sludge in the sludge treatment tank;

[0027] A flocculation unit, connected to the sludge treatment tank, for adding a flocculant into the sludge treatment tank;

[0028] The plate and frame filter press unit is connected to the sludge treatment tank and is used for filter pressing the photovoltaic sludge in the sludge treatment tank after being treated by the pH value adjustment unit and the flocculation unit.

[0029] The above-mentioned photovoltaic sludge dewatering system improves the dewatering rate of photovoltaic sludge by changing the existing method of mixing other sludges with photovoltaic sludge for filter pressing to a method of using flocculants to produce flocculent sludge from photovoltaic sludge and then using a plate and frame filter press unit to filter press and dehydrate the flocculent sludge. On the one hand, it reduces the output of sludge residue, thereby reducing the subsequent disposal cost of sludge residue and saving storage space for sludge residue. On the other hand, sludge residue with low water content reduces the risk of decay, thereby reducing the risk of odor and leachate overflow, meeting environmental protection needs.

[0030] In one embodiment, the photovoltaic sludge dewatering system also includes an aeration unit, which is installed in the sludge treatment tank. The aeration unit is provided with an aeration inlet and an aeration outlet. The aeration inlet is externally connected to a compressed air source, and the aeration outlet is used to transmit the gas in the compressed air source to the sludge treatment tank.

[0031] In one embodiment, the plate and frame filter press unit includes a plate and frame filter press, a sludge discharge pipe and a sludge discharge pump, the two ends of the sludge discharge pipe are respectively connected to the sludge treatment tank and the plate and frame filter press, the sludge discharge pump is arranged on the sludge discharge pipe, and the plate and frame filter press is used to filter the photovoltaic sludge in the sludge treatment tank transported by the sludge discharge pump after being treated by the pH value adjustment unit and the flocculation unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a flowchart of the photovoltaic sludge dehydration process provided in this application.

[0033] Figure 2 Schematic diagram of the photovoltaic sludge dewatering system provided for this application.

[0034] Figure 3 for Figure 2 Schematic diagram of the structure of the aeration unit.

[0035] in:

[0036] 10. Photovoltaic sludge dewatering system;

[0037] 100. Sludge treatment tank;

[0038] 200, pH value adjustment unit; 210, acid adjustment module; 211, acid agent storage tank; 212, second delivery pipe; 213, second delivery pump; 220, alkaline adjustment module; 221, alkaline agent storage tank; 222, third delivery pipe; 223, third delivery pump;

[0039] 300, flocculation unit; 310, flocculation storage tank; 320, first delivery pipe; 330, first delivery pump;

[0040] 400, plate and frame filter press unit; 410, plate and frame filter press; 420, sludge discharge pipe; 430, sludge discharge pump;

[0041] 500, aeration unit; 510, aeration main pipe; 520, aeration branch pipe; 521, aeration outlet;

[0042] 600. sedimentation unit; 610. secondary sedimentation tank; 620. sludge feed pipe; 630. sludge feed pump. DETAILED DESCRIPTION

[0043] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0044] In the description of the present application, it should be understood that if 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", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0045] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0046] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0047] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the 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. The first feature being "below", "below" and "below" the 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.

[0048] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0049] The applicant's research found that the traditional way to dehydrate photovoltaic sludge is to use plate and frame filter pressing technology, specifically, the photovoltaic sludge is mixed with other sludges (such as silicon-containing sludge) without adding chemicals and filter pressed. However, the water content of the photovoltaic sludge after filtration is still very high. Testing has found that the water content of the photovoltaic sludge after filtration is about 85%. On the one hand, it increases the subsequent disposal costs of sludge residue, and on the other hand, a large amount of water-containing sludge residue will have the risk of rotting, and it is difficult to meet environmental protection needs.

[0050] To do this, see Figure 1 , Figure 1 The flowchart of the photovoltaic sludge dehydration process provided by the present application is shown. The photovoltaic sludge dehydration process provided by an embodiment of the present application is used to dehydrate photovoltaic sludge. The photovoltaic sludge dehydration process includes the following steps: Step S1, transporting the photovoltaic sludge to the sludge treatment tank. It is not difficult to understand that the sludge treatment tank provides a place for the treatment of photovoltaic sludge; Step S2, adjusting the pH value of the photovoltaic sludge in the sludge treatment tank to provide a suitable acid-base environment for the subsequent flocculation of the flocculant; Step S3, adding flocculant to the sludge treatment tank to form flocculent sludge; Step S4, using a plate and frame filter press unit to filter press and dehydrate the photovoltaic sludge in the sludge treatment tank. It should be noted that after the flocculent sludge is generated in the sludge treatment tank, the plate and frame filter press unit performs filter press and dehydration on the entire photovoltaic sludge in the sludge treatment tank, and the photovoltaic sludge produces separated liquid and sludge residue after the filter press and dehydration. The liquid can continue to be used in the manufacturing process of photovoltaic slices, and the sludge residue needs to be outsourced.

[0051] The photovoltaic sludge dehydration process is as follows: the photovoltaic sludge is transported to the sludge treatment pool to obtain the photovoltaic sludge treatment site through step S1; the pH value of the photovoltaic sludge in the sludge treatment pool is adjusted through step S2, so that the sludge treatment pool has a suitable acid-base environment; after adding flocculant to the sludge treatment pool in step S3, flocculent sludge is formed under a suitable acid-base environment; finally, the photovoltaic sludge in the sludge treatment pool is filtered and dehydrated by a plate and frame filter press unit. Through the above settings, the existing method of mixing other sludges with photovoltaic sludge for filtering is changed to a method of using a flocculant to make photovoltaic sludge produce flocculent sludge and then using a plate and frame filter press unit to filter and dehydrate the flocculent sludge, thereby improving the dehydration rate of photovoltaic sludge. On the one hand, the output of sludge residue is reduced, thereby reducing the subsequent disposal cost of sludge residue and saving storage space for sludge residue. On the other hand, the sludge residue with low water content reduces the risk of decay, thereby reducing the risk of odor and leachate overflow, meeting environmental protection requirements.

[0052] In order to more conveniently realize the plate-frame filter press unit to filter and dehydrate the photovoltaic sludge in the sludge treatment tank, a preferred embodiment is that the plate-frame filter press unit includes a plate-frame filter press and a sludge discharge pump, and in step S4, specifically includes the following steps: S41, using the sludge discharge pump to pump the photovoltaic sludge in the sludge treatment tank into the plate-frame filter press; S42, the plate-frame filter press performs filter press and dehydration on the photovoltaic sludge. Through the above settings, the present application uses the sludge discharge pump to pump the photovoltaic sludge into the plate-frame filter press to facilitate the plate-frame filter press to filter the photovoltaic sludge.

[0053] It should be noted that, in the process of filtering photovoltaic sludge by the plate and frame filter press, the filter cloth of the filter press is easy to clog, which makes the filter cloth replacement cycle short. When the photovoltaic sludge is mixed with other sludge for filtering without adding chemicals, the filter cloth generally needs to be replaced once every three months. In order to improve the use efficiency of the filter cloth, specifically, the filter cloth model of the plate and frame filter press is 750B, and the air permeability of the filter cloth is 80L. Through the above-mentioned arrangement, the problem of easy clogging of the filter cloth and long feeding time is solved, and the use efficiency of the filter cloth is improved. The filter cloth is replaced once every three months from the original replacement time to a maximum of 6 months. It should be noted that the model of the filter cloth of the plate and frame filter press is not limited to the above-mentioned 750B, and can also be other models such as 750A, 750C, etc. The preferred model of the filter cloth of the plate and frame filter press in this application is 750B.

[0054] It should be emphasized that in addition to the plate and frame filter press technology, the traditional method of dehydrating photovoltaic sludge is also the screw stack dehydration technology. The screw stack dehydration technology requires PAM (polyacrylamide) with a molecular weight of 8 million. On the one hand, the high cost of PAM leads to an increase in the cost of photovoltaic sludge filter press dehydration. On the other hand, the dehydration rate of the screw stack dehydration technology is low. It has been found that the moisture content of the photovoltaic sludge after filtration using the screw stack dehydration technology is about 95%.

[0055] Based on this, in order to reduce the moisture content of photovoltaic sludge after filtration, a preferred embodiment is that the flocculant is polyaluminium chloride (aluminium salt PAC). In the specific setting, the amount of polyaluminium chloride added is one thousandth of the mud-water mixture in the entire sludge treatment tank. Through the above setting, the photovoltaic sludge in the sludge treatment tank shows a good flocculation effect; and the cost of polyaluminium chloride is low, which will not lead to an increase in the cost of photovoltaic sludge filtration and dehydration; and when filtering the flocculent sludge, the flocculent sludge formed by polyaluminium chloride will not cause clogging of the filter cloth of the plate and frame filter press. It should be noted that the good flocculation effect of using polyaluminium chloride is the result obtained by the applicant based on repeated experiments, and when polyaluminium chloride is used as a flocculant, it is most appropriate to adjust the pH value in the sludge treatment tank to between 6.8-7.2.

[0056] It should be noted that the applicant found in the experiment that when PAM is selected as the flocculant, in addition to the high production cost, it is also easy to clog the filter cloth and the flocculation effect is not ideal; when the flocculant is selected as an iron salt PAC such as polyferrous chloride and polyferric chloride, the flocculation effect is not as good as polyaluminum chloride, and the liquid separated by the iron salt PAC is easy to reverse color. For example: when the mud and water mixture contains phosphorus, when the iron salt PAC is used as a flocculant, the separated liquid is red, which increases the subsequent processing cost.

[0057] In order to more conveniently adjust the pH value in the sludge treatment tank to a pH suitable for polyaluminium chloride to exert flocculation, in step S2, the following steps are specifically included: S21, detecting the pH value of the photovoltaic sludge; S22, using the pH value adjustment unit to add an acidic agent and / or an alkaline agent to the sludge treatment tank to adjust the pH value of the photovoltaic sludge to between 6.8 and 7.2. In the specific setting, the acidic agent can be sulfuric acid, but the acidic agent of the present application is not limited to the above sulfuric acid, and can be other acidic agents except sulfuric acid; the alkaline agent can be alkaline substances such as sodium hydroxide and sodium carbonate, but the alkaline agent of the present application is not limited to the above sodium hydroxide and sodium carbonate, and can also be other alkaline agents such as sodium bicarbonate and potassium hydroxide.

[0058] In order to make the flocculant, acidic agent, and / or alkaline agent mix evenly with the photovoltaic sludge, a preferred embodiment, between step S3 and step S4, further includes the following steps: using an aeration unit to inject compressed gas into the sludge treatment tank so that the photovoltaic sludge, flocculant, acidic agent, and / or alkaline agent are evenly mixed. In the specific setting, the aeration unit is installed in the sludge treatment tank and is 10 cm away from the bottom of the sludge treatment tank.

[0059] In order to more conveniently transport the photovoltaic sludge to the sludge treatment tank, a preferred implementation method, in step S1, specifically includes the following steps: the sludge feed pump pumps the photovoltaic sludge in the secondary sedimentation tank into the sludge treatment tank. It should be noted that in the process of using the A2O process to treat photovoltaic wastewater, the photovoltaic sludge will be discharged to the secondary sedimentation tank for sedimentation, which is convenient for the sludge feed pump to pump the photovoltaic sludge into the sludge treatment tank for related treatment.

[0060] Combination Figure 2 As shown, Figure 2 This is a schematic diagram of the photovoltaic sludge dewatering system provided in the present application. In some embodiments, the present application also provides a photovoltaic sludge dewatering system 10 for implementing the photovoltaic sludge dewatering process described in any of the above embodiments. The photovoltaic sludge dewatering system 10 includes a sludge treatment tank 100, a pH adjustment unit 200, a flocculation unit 300 and a plate and frame filter press unit 400.

[0061] The sludge treatment tank 100 is used to provide a place for treating photovoltaic sludge. It should be understood that the sludge treatment tank 100 contains photovoltaic sludge to be treated; the pH value adjusting unit 200 is connected to the sludge treatment tank 100, and the pH value adjusting unit 200 is used to adjust the pH value of the photovoltaic sludge in the sludge treatment tank 100. During specific operation, the pH value adjusting unit 200 is used to add acidic agents and / or alkaline agents to the sludge treatment tank 100. It is not difficult to understand that the pH value of the photovoltaic sludge is adjusted to provide a suitable flocculation environment for the subsequent flocculation unit 300; the flocculation unit 300 is connected to the sludge treatment tank 100, and the flocculation unit 300 It is used to add flocculants into the sludge treatment tank 100, and the flocculants make the photovoltaic sludge form flocculent sludge under a suitable acid-base environment; the plate and frame filter press unit 400 is connected to the sludge treatment tank 100, and the plate and frame filter press unit 400 is used to filter press the photovoltaic sludge in the sludge treatment tank 100 after being treated by the pH value adjustment unit 200 and the flocculation unit 300. During specific operation, after flocculent sludge is generated in the sludge treatment tank 100, the entire photovoltaic sludge in the sludge treatment tank 100 is filtered and dehydrated, and after the photovoltaic sludge is filtered and dehydrated, separated liquid and sludge residue are generated. The liquid can continue to be used in the manufacturing process of photovoltaic slices, and the sludge residue needs to be outsourced for treatment.

[0062] The above-mentioned photovoltaic sludge dewatering system 10, by setting a pH value adjustment unit 200 connected to the sludge treatment tank 100, makes the photovoltaic sludge in the sludge treatment tank 100 be in a suitable acid-base environment, which is convenient for the subsequent flocculation unit 300 to add flocculants into the sludge treatment tank 100 to make the photovoltaic sludge produce flocculent sludge, and then use the plate and frame filter press unit 400 to filter and dehydrate the flocculent sludge to improve the dehydration rate of the photovoltaic sludge. It has been found through testing that after the photovoltaic sludge is filtered by the above-mentioned photovoltaic sludge dewatering system 10, the moisture content of the photovoltaic sludge is less than 75%. Through the above arrangement, the existing method of mixing other sludges with photovoltaic sludge for filter pressing is changed to a method of using flocculants to produce flocculent sludge from photovoltaic sludge and then using a plate and frame filter press unit 400 to filter and dehydrate the flocculent sludge. This improves the dehydration rate of photovoltaic sludge. On the one hand, it reduces the output of sludge residue, thereby reducing the subsequent disposal costs of sludge residue and saving storage space for sludge residue. On the other hand, sludge residue with low water content reduces the risk of decay, thereby reducing the risk of odor and leachate overflow, thereby meeting environmental protection needs.

[0063] Combination Figure 3 As shown, Figure 3 for Figure 2 Schematic diagram of the structure of the aeration unit 500 in the aeration unit 500. In some embodiments, in order to make the flocculant, acidic agent, and / or alkaline agent mixed evenly with the photovoltaic sludge, the photovoltaic sludge dehydration system 10 also includes an aeration unit 500, which is installed in the sludge treatment tank 100. The aeration unit 500 is provided with an aeration inlet and an aeration outlet 521. The aeration inlet is externally connected to a compressed air source, and the aeration outlet 521 is used to transmit the gas in the compressed air source to the sludge treatment tank 100. In the specific setting, the aeration inlet and the outlet of the external compressed air source are connected through an aeration valve. In the specific operation, after the flocculation unit 300 adds the flocculant to the sludge treatment tank 100, flocculent sludge is formed in the sludge treatment tank 100, and then the aeration valve is opened.

[0064] In order to simplify the structure of the aeration unit 500, specifically, the aeration unit 500 includes an aeration main pipe 510 and an aeration branch pipe 520 connected to the aeration main pipe 510, an aeration air inlet is provided in the aeration main pipe 510, and an aeration air outlet 521 is provided in the aeration branch pipe 520. In specific settings, the aeration main pipe 510 and the aeration branch pipe 520 are connected at a set angle, and the specific angle can be any value between 0° and 180°. In the present application, it is preferred that the aeration main pipe 510 and the aeration branch pipe 520 are arranged at 90°, that is, perpendicular to each other.

[0065] In order to ensure that compressed gas can be filled into each position in the sludge treatment tank 100 , more specifically, there are multiple aeration branch pipes 520 , which are spaced apart along the length direction of the aeration main pipe 510 . In the specific setting, an aeration branch pipe 520 is arranged at a set distance in the length direction of the aeration main pipe 510, and the specific set distance can be any value such as 20 cm, 30 cm, etc.; the aeration main pipe 510 and the aeration branch pipe 520 can both be made of UPVC (Unplasticized PolyvinylChloride) or stainless steel; and the aeration main pipe 510 extends along the length direction of the sludge treatment tank 100, that is, the length direction of the aeration main pipe 510 is parallel to the length direction of the sludge treatment tank 100, and multiple aeration branch pipes 520 are arranged along the length direction of the aeration main pipe 510, that is, multiple aeration branch pipes 520 are arranged at intervals along the length direction of the sludge treatment tank 100, and each aeration branch pipe 520 is provided with an aeration outlet, so that compressed gas can be filled into the sludge treatment tank 100 at each set distance.

[0066] In order to increase the amount of compressed gas charged, more specifically, the number of aeration outlets 521 is multiple, and the multiple aeration outlets 521 are arranged at intervals along the length direction of the aeration branch pipe 520. In the specific arrangement, the multiple aeration outlets 521 can be distributed at equal intervals along the length direction of the aeration branch pipe 520, and the distance between two adjacent aeration outlets 521 is 10 cm, but is not limited to the above 10 cm. The distance between two adjacent aeration outlets 521 can be any value set according to the length of the aeration branch pipe 520; the shape of the aeration outlet 521 can be any geometric shape such as circular, elliptical, rectangular, prismatic, etc., and the preferred shape of the aeration outlet 521 in the present application is circular.

[0067] In order to more conveniently realize the filtration of photovoltaic sludge by the plate and frame filter press unit 400, a preferred embodiment is that the plate and frame filter press unit 400 includes a plate and frame filter press 410, a sludge discharge pipe 420 and a sludge discharge pump 430, the two ends of the sludge discharge pipe 420 are respectively connected to the sludge treatment tank 100 and the plate and frame filter press 410, the sludge discharge pump 430 is arranged on the sludge discharge pipe 420, and the plate and frame filter press 410 is used for filtering the photovoltaic sludge treated by the pH adjustment unit 200 and the flocculation unit 300 in the sludge treatment tank 100 and transported by the sludge discharge pump 430.

[0068] The sludge discharge pump 430 is used to transport the photovoltaic sludge treated by the pH adjustment unit 200 and the flocculation unit 300 to the plate and frame filter press 410 along the sludge discharge pipe 420. In order to ensure the efficiency of the filtration, the sludge discharge pump 430 is generally set as a screw pump, and the pumping pressure of the screw pump is not less than 7 kg / cm2 to ensure the efficiency of the screw pump feeding; and when the pressure of the plate and frame filter press 410 reaches 7 kg / cm2, the filtration program of the plate and frame filter press 410 is started. It should be noted that the sludge discharge pump 430 is not limited to the above-mentioned screw pump, and can also be a pneumatic diaphragm pump to reduce energy consumption; it can be a ceramic plunger pump to obtain a large pumping power. In order to improve the efficiency of pumping photovoltaic sludge, a plunger pump can be set to feed two plate and frame filter presses 410 at the same time.

[0069] In order to make the sludge discharge pipe 420 resistant to corrosion and not easy to break, the sludge discharge pipe 420 is generally made of stainless steel. The above arrangement also makes the sludge discharge pipe 420 have a strong pressure bearing capacity. When the sludge discharge pipe 420 is specifically arranged, one end of the sludge discharge pipe 420 is arranged in the sludge treatment tank 100 and is within a range of 20cm-50cm from the bottom of the sludge treatment tank 100. The specific position of the sludge discharge pipe 420 from the bottom of the sludge treatment tank 100 is adjusted according to the height of the sludge treatment tank 100, so that the sludge discharge pump 430 can pump the photovoltaic sludge in the sludge treatment tank 100.

[0070] In order to more conveniently implement the addition of flocculants from the flocculation unit 300 to the sludge treatment tank 100, in a preferred embodiment, the flocculation unit 300 includes a flocculation storage tank 310, a first delivery pipe 320, and a first delivery pump 330. The flocculation storage tank 310 stores flocculants, and the two ends of the first delivery pipe 320 are respectively connected to the flocculation storage tank 310 and the sludge treatment tank 100, and the first delivery pump 330 is arranged on the first delivery pipe 320. When in use, the first delivery pump 330 is used to deliver the flocculants in the flocculation storage tank 310 to the sludge treatment tank 100 along the first delivery pipe 320. Through the above arrangement, the flocculants can be quickly added to the sludge treatment tank 100 by turning on the first delivery pump 330.

[0071] In order to more conveniently realize that the pH value adjusting unit 200 adjusts the pH value of the photovoltaic sludge in the sludge treatment tank 100, in a preferred embodiment, the pH value adjusting unit 200 includes an acidic adjusting module 210 and an alkaline adjusting module 220 connected to the sludge treatment tank 100, the acidic adjusting module 210 is used to transport the acidic agent to the sludge treatment tank 100, and the alkaline adjusting module 220 is used to transport the alkaline agent to the sludge treatment tank 100. Through the above configuration, the acidic agent can be added to the sludge treatment tank 100 through the acidic adjusting module 210, and / or the alkaline agent can be added to the sludge treatment tank 100 through the alkaline adjusting module 220, so as to adjust the pH in the sludge treatment tank 100 to the required pH value.

[0072] In the specific setting, the acid adjustment module 210 includes an acid agent storage tank 211, a second delivery pipe 212 and a second delivery pump 213, wherein: the acid agent storage tank 211 stores an acid agent, and the acid agent can specifically be sulfuric acid, but the acid agent of the present application is not limited to the above-mentioned sulfuric acid, and can be other acid agents except sulfuric acid; the two ends of the second delivery pipe 212 are respectively connected to the acid agent storage tank 211 and the sludge treatment tank 100, and the second delivery pump 213 is arranged on the second delivery pipe 212. The second delivery pump 213 is used to transport the acid agent in the acid agent storage tank 211 along the second delivery pipe 212 to the sludge treatment tank 100. Through the above setting, turning on the second delivery pump 213 can quickly add the acid agent to the sludge treatment tank 100 to adjust the pH value of the sludge treatment tank 100.

[0073] The alkaline adjustment module 220 includes an alkaline agent storage tank 221, a third delivery pipe 222 and a third delivery pump 223, wherein: the alkaline agent storage tank 221 stores an alkaline agent, and the alkaline agent can specifically be an alkaline substance such as sodium hydroxide and sodium carbonate, but the alkaline agent of the present application is not limited to the above-mentioned sodium hydroxide and sodium carbonate, and can also be other alkaline agents such as sodium bicarbonate and potassium hydroxide; both ends of the third delivery pipe 222 are respectively connected to the alkaline agent storage tank 221 and the sludge treatment tank 100, and the third delivery pump 223 is arranged on the third delivery pipe 222. The third delivery pump 223 is used to transport the alkaline agent in the alkaline agent storage tank 221 along the third delivery pipe 222 to the sludge treatment tank 100. Through the above arrangement, turning on the third delivery pump 223 can quickly add alkaline agent to the sludge treatment tank 100 to adjust the pH value of the sludge treatment tank 100.

[0074] In order to more conveniently transport the photovoltaic sludge to the sludge treatment tank 100 for related treatment, the photovoltaic sludge dehydration system 10 includes a sedimentation unit 600, which includes a secondary sedimentation tank 610, a sludge feed pipe 620 and a sludge feed pump 630. The secondary sedimentation tank 610 has photovoltaic sludge, and the two ends of the sludge feed pipe 620 are respectively connected to the secondary sedimentation tank 610 and the sludge treatment tank 100. The sludge feed pump 630 is arranged on the sludge feed pipe 620, and the sludge feed pump 630 is used to pump the photovoltaic sludge in the secondary sedimentation tank 610 into the sludge treatment tank 100. It is not difficult to understand that the sludge feed pump 630 pumps the photovoltaic sludge in the secondary sedimentation tank 610 into the sludge treatment tank 100 along the sludge feed pipe 620.

[0075] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A photovoltaic sludge dehydration process, characterized in that: The steps include: S1, transporting photovoltaic sludge to the sludge treatment pool; S2. adjusting the pH value of the photovoltaic sludge in the sludge treatment tank; S3, adding flocculant to the sludge treatment tank to form flocculent sludge; S4. Utilizing a plate and frame filter press unit to filter press and dehydrate the photovoltaic sludge in the sludge treatment tank.

2. The photovoltaic sludge dehydration process according to claim 1, characterized in that: The plate-frame filter press unit includes a plate-frame filter press and a sludge discharge pump. In step S4, the steps are specifically as follows: S41, using the sludge discharge pump to pump the photovoltaic sludge in the sludge treatment tank into the plate and frame filter press; S42, the plate and frame filter press performs filter pressing and dehydration on the photovoltaic sludge.

3. The photovoltaic sludge dehydration process according to claim 2, characterized in that: The model of the filter cloth of the plate and frame filter press is 750B, and the air permeability of the filter cloth is 80L.

4. The photovoltaic sludge dehydration process according to claim 1, characterized in that: The flocculant is polyaluminium chloride.

5. The photovoltaic sludge dehydration process according to claim 1, characterized in that: In step S2, the following steps are specifically included: S21, detecting the pH value of the photovoltaic sludge; S22. Using a pH value adjustment unit, add an acidic agent and / or an alkaline agent to the sludge treatment tank to adjust the pH value of the photovoltaic sludge to between 6.8 and 7.

2.

6. The photovoltaic sludge dehydration process according to claim 5, characterized in that: Between step S3 and step S4, the following steps are also included: Compressed gas is injected into the sludge treatment tank by using an aeration unit so that the photovoltaic sludge is evenly mixed with the flocculant, the acidic agent, and / or the alkaline agent.

7. The photovoltaic sludge dehydration process according to claim 1, characterized in that: In step S1, the following steps are specifically included: The sludge feed pump pumps the photovoltaic sludge in the secondary sedimentation tank into the sludge treatment tank.

8. A photovoltaic sludge dehydration system for implementing the photovoltaic sludge dehydration process according to any one of claims 1 to 7, characterized in that: The photovoltaic sludge dewatering system comprises: Sludge treatment pool, used to provide a place for treating photovoltaic sludge; A pH value adjustment unit, connected to the sludge treatment tank, for adjusting the pH value of the photovoltaic sludge in the sludge treatment tank; A flocculation unit, connected to the sludge treatment tank, for adding a flocculant into the sludge treatment tank; The plate and frame filter press unit is connected to the sludge treatment tank and is used for filter pressing the photovoltaic sludge in the sludge treatment tank after being treated by the pH value adjustment unit and the flocculation unit.

9. The photovoltaic sludge dehydration system according to claim 8, characterized in that: The photovoltaic sludge dehydration system also includes an aeration unit, which is installed in the sludge treatment tank. The aeration unit is provided with an aeration inlet and an aeration outlet. The aeration inlet is externally connected to a compressed air source, and the aeration outlet is used to transmit the gas in the compressed air source to the sludge treatment tank.

10. The photovoltaic sludge dehydration system according to claim 8, characterized in that: The plate and frame filter press unit includes a plate and frame filter press, a sludge discharge pipe and a sludge discharge pump. The two ends of the sludge discharge pipe are respectively connected to the sludge treatment tank and the plate and frame filter press. The sludge discharge pump is arranged on the sludge discharge pipe. The plate and frame filter press is used to filter the photovoltaic sludge in the sludge treatment tank transported by the sludge discharge pump after being treated by the pH value adjustment unit and the flocculation unit.

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