Simulation device and method for recycling treatment of production wastewater

Abstract

The invention discloses a production wastewater reuse treatment simulation device and method.The production wastewater reuse treatment simulation device comprises a mixing tank, a solution tank and a steel structure model frame, the steel structure model frame is divided into a pre-sedimentation tank and a sedimentation tank, and a first water outlet pipe communicated with the water outlet end of the mixing tank and the water inlet end of the pre-sedimentation tank are arranged between the water outlet end of the mixing tank and the water inlet end of the sedimentation tank; a second communicated water outlet pipe is arranged between the water outlet end of the mixing tank and the water inlet end of the sedimentation tank, a communicating water pipe is further arranged between the pre-sedimentation tank and the sedimentation tank in a communicating manner, and valves are arranged on the first water outlet pipe, the second water outlet pipe and the communicating water pipe; a multi-parameter analyzer is arranged at the water outlet end of each of the mixing tank and the sedimentation tank, and is used for analyzing the water quality index change condition before and after the backwashing water and the sludge water are recycled, further obtaining the upper limit or threshold value of the backwashing water and the sludge water recycling, and guiding the dosing to realize the water purification; therefore, when the device is applied to treatment of backwash water or sludge water generated by a water plant, water resources can be saved, and the device has extremely high popular science value.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and in particular to a production wastewater reuse treatment simulation device and method. Background Art

[0002] Increasingly severe water shortages and pollution pose new challenges for my country's water treatment plants. While continuously improving their water supply capacity and ensuring total water supply, water plants must also strictly control the volume and quality of wastewater generated during their production processes, minimizing the risk of exacerbated environmental pollution from direct discharge into water bodies. This situation has led to the emergence of wastewater reuse technologies for water treatment plants. Water treatment plant wastewater primarily consists of filter backwash wastewater and sludge water from the coagulation and sedimentation processes. These two streams can account for up to 10% of a water plant's total water production. Reusing these two streams can alleviate water supply pressure and generate significant water resource benefits for water treatment plants. Furthermore, sludge water and backwash wastewater contain significant amounts of suspended particles and residual coagulant that has not fully reacted during the coagulation stage. Reusing this wastewater can increase the probability of particle collisions during the flocculation process, improve coagulation effectiveness, and thus reduce coagulant usage and operating costs for water plants. Therefore, establishing and improving a safe and efficient waterworks wastewater reuse process can take into account both water conservation and chemical conservation, and has broad research and application prospects.

[0003] However, there are currently no relevant reuse standards in the industry. Therefore, a production wastewater reuse treatment simulation device and method are provided for reuse research. The device can simulate the water quality of backwash water and sludge water reused by different water plants in different seasons and with different Yangtze River water sources, and determine the reuse ratio, reuse limit and other parameters of the filter backwash water and sludge water, thereby providing a basis for the water plant to reuse backwash water and sludge water, and laying the foundation for the next step of research. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a production wastewater reuse treatment simulation device and method that can provide a basis for water plants to reuse backwash water and sludge water.

[0005] The technical solution is as follows: a production wastewater reuse treatment simulation device, including a mixing tank, a solution tank and a steel structure model frame. The key points are: the steel structure model frame is divided into a pre-sedimentation tank and a sedimentation tank by a partition, wherein the front side is a transparent glass partition, the water outlet end of the mixing tank is connected to the pre-sedimentation tank and the sedimentation tank at the same time, a first water outlet pipe is arranged between the water outlet end of the mixing tank and the water inlet end of the pre-sedimentation tank, a second water outlet pipe is arranged between the water outlet end of the mixing tank and the water inlet end of the sedimentation tank, a connecting water pipe is also arranged between the pre-sedimentation tank and the sedimentation tank, valves are arranged on the first water outlet pipe, the second water outlet pipe and the connecting water pipe, and multi-parameter analyzers are arranged at the water outlet ends of the mixing tank and the sedimentation tank. With the above structure, the mixing tank can be used to configure a certain proportion of backwash water and Yangtze River water, or a certain proportion of sludge water and Yangtze River water. After the configuration is completed, it is discharged into the pre-sedimentation tank and the sedimentation tank in sequence, or in special circumstances, the water in the mixing tank is directly discharged into the sedimentation tank for treatment, thereby removing impurities or suspended matter in the water. The various process parameters of the pre-sedimentation tank and the sedimentation tank are consistent with the production process of the water plant, simulating the production operation of the water plant. By collecting, counting and analyzing the experimental data of the above simulation device, a basis is provided for the reuse and purification treatment of the backwash water or sludge water of the water plant, thereby achieving the purpose of saving water resources and protecting the environment.

[0006] Preferably, the mixing tank includes a left mixing tank and a right mixing tank, the left and right mixing tanks being interconnected and of uniform size. An agitator is provided in the mixing tank, and the multi-parameter analyzer includes a first multi-parameter analyzer and a second multi-parameter analyzer, wherein the first multi-parameter analyzer is provided in the mixing tank. With the above structure, the agitator can evenly mix a certain proportion of backwash water and Yangtze River water, or a certain proportion of sludge water and Yangtze River water, entering the mixing tank. The left and right mixing tanks are interconnected and of uniform size, ensuring that the sludge water entering the pre-sedimentation tank and sedimentation tank at the same time is consistent. The first multi-parameter analyzer can detect various water quality parameters in the mixing tank.

[0007] Preferably, the outlet of the left mixing tank is connected to the pre-sedimentation tank via a first outlet pipe, and the outlet of the left mixing tank is connected to the sedimentation tank via a second outlet pipe. The first and second outlet pipes are connected to one end of a dosing pipe, the other end of which is connected to the solution tank. Tubular static mixers are installed in both the first and second outlet pipes. With this structure, the liquid medicine in the solution tank can be directly added to the first and second outlet pipes leading to the pre-sedimentation tank and sedimentation tank via the dosing pipe. The static mixer ensures uniform mixing of the liquid medicine and muddy water, facilitating subsequent reactions and treatments.

[0008] Preferably, the pre-sedimentation tank includes a first flocculation zone, a first transition zone, and a first inclined tube sedimentation zone, with a first row of sludge hoppers disposed at the bottom of the pre-sedimentation tank. With this structure, the first flocculation zone aggregates suspended matter and colloidal particles in the mixing tank water into larger flocs, facilitating sedimentation and separation in the pre-sedimentation tank. Sedimentation occurs through the first transition zone and the first inclined tube sedimentation zone, and the sediment is discharged through the first row of sludge hoppers.

[0009] Preferably, the inlet of the pre-sedimentation tank communicates with the first flocculation zone, the outlet of the first flocculation zone is connected to the inlet of the first transition zone, the outlet of the first transition zone communicates with the inlet of the first inclined tube sedimentation tank, and the other end of the first inclined tube sedimentation tank is provided with a pre-sedimentation tank outlet. With this structure, the sequential connection of various sections of the pre-sedimentation tank allows for the removal of both settleable and floating matter from the wastewater, further reducing the load on subsequent treatment steps and enhancing the solid-liquid separation effect.

[0010] Preferably, the first flocculation zone of the pre-sedimentation tank is a perforated cyclone reaction tank, and the first flocculation zone includes a flocculation zone A1, a flocculation zone A2, a flocculation zone A3 and a flocculation zone A4 which are connected in sequence, wherein the areas of the flocculation zone A1 and the flocculation zone A4 are the same, and the areas of the flocculation zone A2 and the flocculation zone A3 are the same;

[0011] The first inclined tube sedimentation tank sequentially comprises a first clear water zone, a first inclined tube zone, and a first water distribution zone. The parameters of the inclined tube zone are: 1m in length, 35mm in margin, 0.4mm in tube thickness, and a 60° horizontal inclination angle. With this structure, water discharged from the mixing tank can sequentially pass through flocculation zones A1, A2, A3, and A4. The perforated cyclone reaction tank causes the muddy water to rotate at high speed, achieving high shear and impact forces, thereby improving reaction efficiency, accelerating reaction speed, and shortening reaction time. This can accelerate the settling rate of suspended particles in the raw water and achieve solid-liquid separation. The first inclined tube sedimentation zone can also improve sedimentation efficiency.

[0012] Preferably, the sedimentation tank includes a second flocculation zone, a second transition zone, and a second inclined tube sedimentation tank, with a second row of sludge hoppers disposed at the bottom of the sedimentation tank and a second multi-parameter analyzer disposed within the sedimentation tank. With this structure, sedimentation and separation are achieved within the sedimentation tank through the second flocculation zone, the second transition zone, and the second inclined tube sedimentation tank, and the sediment can be discharged through the second row of sludge hoppers. The water quality in the sedimentation tank can also be monitored using the second multi-parameter analyzer.

[0013] Preferably, the inlet of the sedimentation tank communicates with the second flocculation zone, the outlet of the second flocculation zone is connected to the inlet of the second transition zone, the outlet of the second transition zone communicates with the inlet of the second inclined tube sedimentation tank, and the other end of the second inclined tube sedimentation tank is provided with a pre-sedimentation tank outlet. With this structure, raw water from the mixing tank or treated water from the pre-sedimentation tank enters the sedimentation tank, and after sequentially passing through the second flocculation zone, the second transition zone, and the second inclined tube sedimentation zone, suspended solids are settled to the tank bottom, achieving separation and purification.

[0014] Preferably, the second flocculation zone is a grid cyclone reaction tank, and six sedimentation flocculation zones are arranged in an S-shape inside the second flocculation zone, including a flocculation zone B1, a flocculation zone B2, a flocculation zone B3, a flocculation zone B4, a flocculation zone B5 and a flocculation zone B6 that are connected in sequence, wherein the areas of the flocculation zones B1, B4 and B5 are the same, and the areas of the flocculation zones B2, B3 and B6 are the same;

[0015] The second inclined tube sedimentation tank sequentially comprises a second clear water zone, a second inclined tube zone, and a second water distribution zone. The parameters of the inclined tube zone are: 1 meter in length, 35 mm side spacing, 0.4 mm tube thickness, and a horizontal inclination angle of 60°. With the above structure, the grid serves to enhance hydraulic pressure, enabling the reagent and suspended particles in the water to form flocs.

[0016] A method for treating production wastewater for reuse comprises the following steps:

[0017] Step 1: Mix the sludge water and backwash water in a ratio of 4:1, and then mix them with the raw water in a certain ratio in the mixing tank;

[0018] Step 2: Detecting water quality data in the mixing tank and the sedimentation tank using a first multi-parameter analyzer and a second multi-parameter analyzer;

[0019] Step 3: Adjust the amount of coagulant in the solution pool according to the data in step 2, and add it into the sedimentation tank or pre-sedimentation tank through the dosing pipe.

[0020] Step 4: Determine the mixing ratio of the recycled sludge water and backwash water with the raw water and the amount of coagulant added.

[0021] The backwash water sampling method in step 1 is: During the filter backwash period, water samples are collected at the water outlet every 1 minute. The backwash period lasts for 12 minutes. The 12 water samples obtained are combined to obtain the backwash water test sample. The sludge water sampling method is: water samples are collected directly at the sludge tank outlet.

[0022] In step 3, the dosage of coagulant is determined by the drug saving rate.

[0023] Chemical saving rate (%) = (optimal raw water dosage - optimal mixed water dosage) / optimal raw water dosage

[0024] ×100%

[0025] In the formula, the optimal dosage unit for raw water and mixed water is mg / L.

[0026] By detecting the water quality before and after treatment with the first and second multi-parameter analyzers, it is possible to determine whether the treated water meets the usage standards, and to confirm the optimal dosage through the backwash water and sludge water with different reuse ratios and the measured data. This can not only save water, but also enhance the treatment effect, significantly reduce the amount of drugs consumed, and thus reduce the operating costs of the water plant.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: it can simulate the production operation of a water plant in different seasons and with different Yangtze River water sources, mix Yangtze River water with backwash water or sludge water, and pass the mixture into a pre-sedimentation tank and a sedimentation tank for effective treatment, and analyze the changes in water quality indicators before and after the reuse of backwash water and sludge water according to the parameters of a multi-parameter analyzer, and further derive the upper limit or threshold for the reuse of backwash water and sludge water, while guiding the dosing of drugs to achieve water purification, save water resources, and protect the environment; at the same time, the front side is separated by glass, so that the formation and sedimentation of alum flowers can be easily observed, avoiding the shortcomings of traditional process pools that can only observe the surface and beaker stirring that is only static observation; further, this scheme simulates various production experiments in a visual way, and has extremely high popular science value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a simplified schematic diagram of the present invention;

[0029] Figure 2 This is the plan view of the pre-sedimentation tank 2;

[0030] Figure 3 is a cross-sectional view of the pre-sedimentation tank 3;

[0031] Figure 4 is a plan view of sedimentation tank 3;

[0032] Figure 5 is a cross-sectional view of sedimentation tank 3;

[0033] Figure 6 Process comparison data chart. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0035] like Figure 1As shown, a production wastewater reuse treatment simulation device includes a mixing tank 1, a solution tank 5 and a steel structure model frame. The steel structure model frame is divided into a pre-sedimentation tank 2 and a sedimentation tank 3 by a partition, wherein the front side is a transparent glass partition. The various process parameters of the pre-sedimentation tank and the sedimentation tank are consistent with the production process of the water plant. The water outlet end of the mixing tank 1 is connected to the pre-sedimentation tank 2 and the sedimentation tank 3 at the same time. A first water outlet pipe 2a is provided between the water outlet end of the mixing tank 1 and the water inlet end of the pre-sedimentation tank 2. A second outlet pipe 2a is provided between the outlet end of the mixing tank 1 and the inlet end of the sedimentation tank 3. Valves are provided on the first outlet pipe 2a, the second outlet pipe 3a and the connecting water pipe 4. The diameter of the first outlet pipe 2a and the second outlet pipe 3a of the mixing tank 1 is DN100, and the pipe material is a plastic-lined pipe. There is no hydraulic height difference between the mixing tank 1 and the pre-sedimentation tank 2 and the sedimentation tank 3, and water is fed by gravity flow. A lifting pump is provided at the outlet pipe end of the mixing tank 1 to lift the water to the pre-sedimentation tank 2 and the sedimentation tank 3. The mixing tank 1 is composed of a certain proportion of Yangtze River water and backwash water or mud water. Therefore, the water in the mixing tank 1 contains a certain mixture of impurities and particulate matter. A booster water pump is installed outside the mixing tank 1. The selected water pump is a pipeline sewage pump. The height difference between the water outlet of the mixing tank 1 and the pre-sedimentation tank 2 / sedimentation tank 3 is 5m, and the pipeline sewage pump has a lift of 10m. A connecting water pipe 4 is also provided between the pre-sedimentation tank 2 and the sedimentation tank 3. The water in the pre-sedimentation tank 2 can be discharged into the sedimentation tank 3 through the connecting water pipe 4. Multi-parameter analyzers are provided at the water outlet ends of the mixing tank 1 and the sedimentation tank 3. The front side of the device adopts a glass structure and is transparent, which makes it easy to observe the formation and sedimentation of alum flowers in the device.

[0036] The multi-parameter analyzer can detect a variety of water quality parameters, such as temperature, turbidity, pH, dissolved oxygen, conductivity, ammonia nitrogen, nitrate, color, suspended solids, residual chlorine, total chlorine, combined chlorine, chlorine dioxide, phosphate, chromium, iron, manganese, etc. These parameters together constitute a comprehensive assessment of water quality and provide data support for the subsequent dosing of backwash water or sludge water reuse treatment.

[0037] The mixing tank 1 includes a left mixing tank 1a and a right mixing tank 1b, which are interconnected and have the same size. A stirrer is provided in the mixing tank 3. The multi-parameter analyzer includes a first multi-parameter analyzer and a second multi-parameter analyzer, wherein the first multi-parameter analyzer is provided in the mixing tank 1, and the water conditions of various parts of the mixing tank are made consistent by stirring with the stirrer, and the various water quality parameters in the mixing tank 1 can be detected in real time by the first multi-parameter analyzer. The outlet end of the left mixing tank 1a is connected to the pre-sedimentation tank 2 through the first outlet pipe 2a, and the outlet end of the mixing tank 1 is connected to the sedimentation tank 3 through the second outlet pipe 3a. The first outlet pipe 2a and the second outlet pipe 3a are connected to one end of the dosing pipe 5a, and the other end of the dosing pipe 5a is connected to the solution tank 5 equipped with a liquid level gauge. A dosing metering pump is also provided on the dosing pipe 5a, and a tubular static mixer 6 is provided in both the first outlet pipe 4a and the second outlet pipe 5a.

[0038] like Figure 2 and Figure 3 As shown, the interior of the pre-sedimentation tank 2 is divided into multiple reaction chambers by transparent partitions, including a first flocculation zone 201, a first transition zone 202 and a first inclined tube sedimentation zone 203. A first row of mud hoppers is provided at the bottom of the pre-sedimentation tank 2.

[0039] The water inlet end of the pre-sedimentation tank 2 is connected to the first flocculation zone 201, the outlet end of the first flocculation zone 201 is connected to the inlet end of the first transition zone 202, the outlet end of the first transition zone 202 is connected to the inlet end of the first inclined tube sedimentation tank 203, and the other end of the first inclined tube sedimentation tank 203 is provided with a pre-sedimentation tank outlet 204.

[0040] The first flocculation zone 201 of the pre-sedimentation tank 2 is a perforated cyclone reaction tank. The first flocculation zone 201 includes a flocculation zone A1 201a, a flocculation zone A2 201b, a flocculation zone A3 201c, and a flocculation zone A2 201d, which are sequentially connected. The flocculation zones A1 201a and A2 201d have the same area, and the flocculation zones A2 201b and A3 201c have the same area. When the water flows through the perforated plate, it is dispersed into multiple small streams, increasing the turbulence of the water flow. Subsequently, the water flow enters the cyclone device and forms a rotating flow under the action of centrifugal force. This rotating flow causes suspended particles in the water to be subjected to a greater inertial force, making it easier for them to separate from the water flow and settle. The first inclined tube sedimentation tank 203 sequentially includes a first clear water zone, a first inclined tube zone, and a first water distribution zone.

[0041] Design scale of the pre-sedimentation tank 2: 700m 3 / d=29.2m 3 / h=0.0082m3 / s, and the first flocculation zone of the pre-sedimentation tank 2 is divided into four parts, which are perforated cyclone reaction tanks. The dimensions of flocculation zone A1 201a and flocculation zone A4 201d are 950×900mm, and the dimensions of flocculation zone A2 201b and flocculation zone A3 201c are 950×980mm. The total area of ​​the flocculation zone is 3.572㎡, the effective water depth is 2.5m, and the super height is 0.2m. The dimensions of the first transition zone 202 are 950×1880mm. The dimensions of the first inclined tube sedimentation tank area 203 are 2850×1000mm, with an area of ​​2.85㎡, an effective water depth of 2.2m, and a super height of 0.3m. The inclined tube parameters are (length L=1m, side distance d=35mm, tube thickness 0.4mm, horizontal inclination angle 60°)

[0042] Based on the above parameters and dimensions, the flocculation time of the first flocculation zone 201, the flow rate in the vertical shaft of a single flocculation tank, the flow rate and sedimentation time of the first inclined tube sedimentation zone 203, the volume of the first row of mud hoppers and the diameter of the drainage pipe of the pre-sedimentation tank 2 can be calculated.

[0043] The flocculation time is: t1 = V ÷ Q = (3.572 × 2.5) ÷ 0.0082m 3 / s=18.15min

[0044] Flow rate in a single flocculation tank shaft:

[0045] Flow rate of flocculation zone A1 201a and flocculation zone A4 201d: v1 = Q ÷ A 单 =0.0082m3 / s÷0.855㎡=0.0096m / s

[0046] Flow rate of flocculation zone A2 201b and flocculation zone A3 201c: v2 = Q ÷ A 单 =0.0082m3 / s÷0.931㎡=0.0088m / s

[0047] Flow rate in the inclined tube sedimentation zone: v3 = 0.0082 m3 / s ÷ 2.85 m2 = 2.9 mm / s

[0048] Water flow velocity in the first inclined tube area: v4 = v3 ÷ sin 60° = 2.9 mm / s ÷ 0.866 = 3.35 mm / s

[0049] Sedimentation time: t2 = L ÷ v4 = 1000 ÷ 3.35 = 4.98 min

[0050] The number of mud buckets in the first row is 3, and their sizes and volumes are as follows:

[0051] ①a=0.95, b=0.9, a1=0.218, b1=0.218, h=0.6;

[0052] V1=(2ab+2a1b1+ab1+a1b)×h×1 / 6=0.22083m 3 ;

[0053] ②a=0.95, b=0.98, a1=0.218, b1=0.218, h=0.6;

[0054] V2=(2ab+2a1b1+ab1+a1b)×h×1 / 6=0.2378m 3 ;

[0055] ③a=0.95, b=1, a1=0.218, b1=0.218, h=0.6;

[0056] V3=(2ab+2a1b1+ab1+a1b)×h×1 / 6=0.24201m 3 ;

[0057] If the drainage time t of the pre-sedimentation tank sludge hopper is controlled according to 20s, according to the flow formula: Q=V÷t

[0058] Then the flow rate Q1=V1÷t=0.22083÷20=0.011m3 / s

[0059] Q2=V2÷t=0.2378÷20=0.012m 3 / s

[0060] Q3=V3÷t=0.24201÷20=0.012m 3 / s

[0061] According to the formula Q = vA = uA (2gH) 0.5 and A = π(R / 2) 2 , calculate R:

[0062] where u = 0.62 ψ =0.62 0.98 , H=2.85m;

[0063] R1=0.0566m; R2=0.054m; R3=0.054m;

[0064] The diameters R are 56.6, 54, and 54 mm. It is recommended that the diameter of the drainage pipes in the pre-sedimentation tank 2 should all be 50 mm, and the valve should be a DN50 electric ball valve. The drainage time t of the first row of mud hoppers will be slightly greater than 20 s.

[0065] The interior of the sedimentation tank 3 is divided into multiple reaction chambers by transparent partitions, including a second flocculation zone 301, a second transition zone 302 and a second inclined tube sedimentation tank 302. A second row of mud hoppers is provided at the bottom of the sedimentation tank 3, and a second multi-parameter analyzer is provided in the sedimentation tank 3.

[0066] The water inlet end of the sedimentation tank 3 is connected to the second flocculation zone 301, the outlet end of the second flocculation zone 301 is connected to the inlet end of the second transition zone 302, the outlet end of the second transition zone 302 is connected to the inlet end of the second inclined tube sedimentation tank 303, and the other end of the second inclined tube sedimentation tank 303 is provided with a pre-sedimentation tank outlet 304.

[0067] The second flocculation zone 301 is a grid cyclone reaction tank, and six sedimentation flocculation zones are arranged along an S shape inside the second flocculation zone 301, including flocculation zone B1 301a, flocculation zone B2 301b, flocculation zone B3 301c, flocculation zone B4 301d, flocculation zone B3 301e and flocculation zone B6 301f connected in sequence, wherein the areas of the flocculation zone B1 301a, flocculation zone B4 301d and flocculation zone B3 301e 201e are consistent; wherein the grid cyclone reaction tank divides the water flow through multiple horizontal grids to form local vortices and turbulence, promote particle collision and combination, and produce a "contraction-diffusion" effect when the water flow passes through the grid, and the flow velocity and vortex intensity of each section decrease, forming a progressive flocculation environment, thereby improving the sedimentation efficiency.

[0068] The second inclined tube sedimentation tank 303 includes a second clear water area, a second inclined tube area and a second water distribution area in sequence, wherein the parameters of the inclined tube area are: length 1m, side distance 35mm, tube thickness 0.4mm, and horizontal inclination angle 60°.

[0069] Sedimentation tank 3 is designed for a flow rate of 1000 m³ / d = 41.67 m³ / h = 0.0116 m³ / s. The second flocculation zone 301 is divided into six sections: flocculation zones B1 301a, B4 301d, and B5 301e 201e measure 950 x 970 mm, while flocculation zones B2 301b, B3 301c, and B6 301f measure 950 x 950 mm. The total area of ​​the second flocculation zone 301 is 5.472 m², with an effective water depth of 2.5 m and an overhang of 0.2 m. The second transition zone 302 measures 850 x 2850 mm. The second inclined tube sedimentation area 303 has a size of 1170×2850 mm, an area of ​​3.3345 m2, an effective water depth of 2.5 m, an extra height of 0.3 m, and inclined tube parameters of (length L=1 m, side distance d=35 mm, tube thickness 0.4 mm, horizontal inclination angle 60°).

[0070] Based on the above parameters and dimensions, the flocculation time of the second flocculation zone 301 of the sedimentation tank, the flow velocity in the vertical shaft of a single flocculation tank, the flow velocity and sedimentation time of the second inclined tube sedimentation zone 303, the volume of the second row of mud hoppers and the diameter of the drainage pipe of the sedimentation tank can be calculated.

[0071] The flocculation time of the second flocculation zone 301 is:

[0072] t1`=V`÷Q`=(5.472×2.5)÷0.0116m 3 / s=19.66min

[0073] Flow rate in a single flocculation tank shaft:

[0074] The flow rates of flocculation zone B1 501a, flocculation zone B4 501d and flocculation zone B5 501e201e are:

[0075] v1`=Q`÷A 单 `=0.0116m 3 / s÷0.9215㎡=0.0126m / s

[0076] The flow rates of flocculation zone B2 501b, flocculation zone B3 501c, and flocculation zone B6 501f are:

[0077] v2`=Q`÷A 单 `=0.0116m 3 / s÷0.9025㎡=0.0129m / s

[0078] Flow rate in the second inclined tube sedimentation zone: v3`=0.0116m / s÷3.3345m 2 =3.48mm / s

[0079] Water flow velocity in the inclined tube: v4`=v3`÷sin60°=3.48mm / s÷0.866=4.02mm / s

[0080] Sedimentation time: t2`=L÷v4`=1000÷4.02=4.15min

[0081] There are four second-row hoppers in sedimentation tank 3, and their sizes and volumes are as follows:

[0082] ①a=0.95, b=0.97, a1=0.208, b1=0.208, H=0.45;

[0083] V1=(2ab+2a1b1+ab1+a1b)×H×1 / 6=0.1747m 3 ;

[0084] ②a=0.95, b==0.95, a1=0.208, b1=0.208, H=0.45;

[0085] V2=[S1+S2+(S1+S2) 0.5 ]×H×1 / 3=0.3134m 3 ;

[0086] ③a=0.95, b=0.85, a1=0.208, b1=0.208, H=0.45;

[0087] V3=(2ab+2a1b1+ab1+a1b)×H×1 / 6=0.1557m 3 ;

[0088] ④a=0.95, b=1.17, a1=0.208, b1=0.208, H=0.45;

[0089] V4=(2ab+2a1b1+ab1+a1b)×H×1 / 6=0.2063m 3 ;

[0090] The drainage time t of the second row of mud buckets is controlled according to 20s, according to the flow formula: Q=V÷t

[0091] Then Q1`=0.0087m 3 / s; Q2`=0.0157m 3 / s; Q3`=0.0078m 3 / s; Q4`=0.0103m 3 / s;

[0092] According to the formula Q = vA = uA (2gH) 0.5 and A = π(R / 2) 2 , calculate R:

[0093] Where u = 0.62ψ = 0.620.98, H = 2.85m;

[0094] R1`=0.0486m; R2`=0.0654m; R3`=0.0465m; R4`=0.0529m;

[0095] The diameters R' are 48.6, 65.4, 46.5, and 52.9 mm. It is recommended that the drainage pipes of sedimentation tank 3 be 50, 65, 50, and 50 mm (3 of each), and the valves be DN50, 65, 50, and 50 electric ball valves (3 of each). The drainage time t of the sludge hopper will be about 20s.

[0096] A method for treating production wastewater reuse, comprising a production wastewater reuse treatment simulation device, comprising the following steps:

[0097] Step 1: Mix the sludge water and backwash water in a ratio of 4:1, and then mix them with the raw water in a certain ratio in the mixing tank 1;

[0098] Step 2: Detecting water quality data in the mixing tank 1 and the sedimentation tank 3 by a first multi-parameter analyzer and a second multi-parameter analyzer;

[0099] Step 3: Adjust the amount of coagulant added in the solution tank 5 according to the data in step 2, and add it into the sedimentation tank 3 or pre-sedimentation tank 2 through the dosing pipe 5a.

[0100] Step 4: Determine the mixing ratio of the recycled sludge water and backwash water with the raw water and the amount of coagulant added.

[0101] The backwash water sampling method in step 1 is: During the filter backwash period, water samples are collected at the water outlet every 1 minute. The backwash period lasts for 12 minutes. The 12 water samples obtained are combined to obtain the backwash water test sample. The sludge water sampling method is: water samples are collected directly at the sludge tank outlet.

[0102] In step 3, the coagulant dosage is determined by the drug saving rate. The turbidity of the settled water is defined as the standard turbidity of ≤2NTU in the coagulation sedimentation experiment. The corresponding minimum dosage is defined as the optimal dosage. The drug saving rate can be expressed as the formula:

[0103] Chemical saving rate (%) = (optimal raw water dosage - optimal mixed water dosage) / optimal raw water dosage

[0104] ×100%

[0105] In the formula, the optimal dosage unit for raw water and mixed water is mg / L.

[0106] The above-mentioned sludge water and backwash water are mixed with raw water in proportions of 0%, 2%, 4%, 6%, 8%, 10%, 12%, 14% and 20% respectively.

[0107] The data in the mixing tank 1 detected by the first multi-parameter analyzer and the data in the sedimentation tank 3 detected by the second multi-parameter analyzer are shown in the following table:

[0108] Table 1 Comparison of various data of mixing tank and sedimentation tank

[0109]

[0110] The data in the table above shows that the turbidity of the recycled backwash and sludge water increases significantly after mixing with the raw water. This is because the production wastewater contains a large amount of particulate matter. Reuse increases the concentration of particulate matter in the raw water, causing an increase in turbidity. However, the turbidity of the effluent from sedimentation tank 3 after treatment is significantly lower than that from mixing tank 1, indicating that the return of backwash and sludge water does not cause significant changes in the turbidity of the settled water and the factory water. In addition, the Fe, KMnO4, and ammonia contents in the treated settled water are significantly reduced, meeting the usage standards. It can also be seen that controlling the reuse ratio to 12% not only does not affect the turbidity of the settled water, but actually strengthens coagulation and reduces the turbidity of the effluent.

[0111] The proportion of backwash and sludge water reused in mixing tank 1 affects the dosage of chemicals in pre-sedimentation tank 2 or sedimentation tank 3. The recycled backwash and sludge water contain a large number of flocculent particles that can serve as the core for raw water coagulation, making the flocs more compact and making it easier for impurities in the water to be adsorbed and removed. At the same time, the production wastewater contains some residual flocculant from conventional treatment. This incompletely reacted flocculant will hydrolyze and condense to form positively charged polymers, which promote the removal of impurities in the water through double electron layer compression, net capture and sweeping, and thus enhance coagulation. However, if the recycle ratio continues to increase, once the particulate matter in the mixed water exceeds a certain limit, the charge interaction between the large number of particles will interfere with the sedimentation process, thereby affecting the coagulation effect. At this point, the increased process load of the reuse exceeds the benefit of the increased probability of particle collisions, resulting in an increase in final chemical consumption. Therefore, the dosage needs to be adjusted according to the reuse ratio to avoid excessive dosing, which in turn leads to poor water treatment results.

[0112] At the same time, while maintaining a constant overall wastewater reuse ratio, varying proportions of backwash water and sludge water can affect the coagulation effectiveness of water treatment. A key parameter controlling this process is mixed water turbidity. Within a certain range, the dosage decreases as turbidity increases. However, excessive increases in turbidity beyond this range are detrimental to strengthening the coagulation process and conserving reagents.

[0113] Therefore, reusing production wastewater within a certain reuse ratio and turbidity range can not only save water, but also enhance the coagulation effect, significantly reduce the water plant's drug consumption, and thus reduce the water plant's operating costs.

[0114] like Figure 6As shown in the figure, the relationship between dosage and turbidity over a certain period of time is recorded for both conventional process G-I and reuse process G-II, respectively. A comparative analysis of the two processes reveals that during the long-term operation of backwash water and sludge water reuse, the dosage fluctuations for both processes are relatively uniform. The dosage for reuse process G-II is significantly lower overall than that for conventional process G-I. As can be seen from the figure, the turbidity of the settled water from the G-II reuse process is generally lower than that of the conventional process G-I, remaining stable below 2 NTU. Under the conditions of controlling appropriate reuse parameters, reuse of production wastewater can effectively enhance the coagulation process and improve the coagulation effect. Reuse process G-II can consistently meet the water plant's internal control requirements for a turbidity of less than 2 NTU.

[0115] Finally, it should be noted that the above description is only a preferred embodiment of the present invention. Under the guidance of the present invention, ordinary technicians in this field can make various similar expressions without violating the purpose and claims of the present invention. Such changes fall within the scope of protection of the present invention.

Claims

1. A production wastewater reuse treatment simulation device, comprising a mixing tank (1), a solution tank (5) and a steel structure model frame, characterized in that: The steel structure model frame is divided into a pre-sedimentation tank (2) and a sedimentation tank (3) by a partition, wherein the front side is a transparent glass partition, the water outlet end of the mixing tank (1) is connected to the pre-sedimentation tank (2) and the sedimentation tank (3), a first water outlet pipe (2a) is provided between the water outlet end of the mixing tank (1) and the water inlet end of the pre-sedimentation tank (2), a second water outlet pipe (3a) is provided between the water outlet end of the mixing tank (1) and the water inlet end of the sedimentation tank (3), a connecting water pipe (4) is also provided between the pre-sedimentation tank (2) and the sedimentation tank (3), valves are provided on the first water outlet pipe (2a), the second water outlet pipe (3a) and the connecting water pipe (4), and a multi-parameter analyzer is provided at the water outlet end of the mixing tank (1) and the sedimentation tank (3).

2. The production wastewater reuse treatment simulation device according to claim 1, characterized in that: The mixing tank (1) comprises a left mixing tank (1a) and a right mixing tank (1b), wherein the left mixing tank (1a) and the right mixing tank (1b) are interconnected and have the same size. An agitator is provided at the water outlet end of the mixing tank (1). The multi-parameter analyzer comprises a first multi-parameter analyzer and a second multi-parameter analyzer, wherein the first multi-parameter analyzer is provided in the mixing tank (1).

3. The production wastewater reuse treatment simulation device according to claim 2, characterized in that: The water outlet end of the left mixing tank (1a) is connected to the pre-sedimentation tank (2) via a first water outlet pipe (2a), and the water outlet end of the left mixing tank (1b) is connected to the sedimentation tank (3) via a second water outlet pipe (3a). The first water outlet pipe (2a) and the second water outlet pipe (3a) are connected to one end of a dosing pipe (5a), and the other end of the dosing pipe (5a) is connected to a solution tank (5). Tubular static mixers (6) are provided in both the first water outlet pipe (4a) and the second water outlet pipe (5a).

4. A production wastewater reuse treatment simulation device according to claim 1 or 3, characterized in that: The pre-sedimentation tank (2) comprises a first flocculation zone (201), a first transition zone (202) and a first inclined tube sedimentation zone (203), and a first row of mud hoppers is provided at the bottom of the pre-sedimentation tank (2).

5. The production wastewater reuse treatment simulation device according to claim 4, characterized in that: The water inlet end of the pre-sedimentation tank (2) is connected to the first flocculation zone (201), the outlet end of the first flocculation zone (201) is connected to the inlet end of the first transition zone (202), the outlet end of the first transition zone (202) is connected to the inlet end of the first inclined tube sedimentation tank (203), and the other end of the first inclined tube sedimentation tank (203) is provided with a pre-sedimentation tank outlet (204).

6. The production wastewater reuse treatment simulation device according to claim 5, characterized in that: The first flocculation zone (201) of the pre-sedimentation tank (2) is a perforated cyclone reaction tank, and the first flocculation zone (201) includes a flocculation zone A1 (201a), a flocculation zone A2 (201b), a flocculation zone A3 (201c) and a flocculation zone A2 (201d) which are connected in sequence, wherein the areas of the flocculation zone A1 (201a) and the flocculation zone A2 (201d) are the same, and the areas of the flocculation zone A2 (201b) and the flocculation zone A3 (201c) are the same; The first inclined tube sedimentation tank (203) comprises a first clear water area, a first inclined tube area and a first water distribution area in sequence, wherein the parameters of the inclined tube area are: length 1m, side distance 35mm, tube thickness 0.2mm, and horizontal inclination angle 60°.

7. The production wastewater reuse treatment simulation device according to claim 1 or 3, characterized in that: The sedimentation tank (3) comprises a second flocculation zone (301), a second transition zone (302) and a second inclined tube sedimentation tank (302); a second row of mud hoppers is provided at the bottom of the sedimentation tank (3); and a second multi-parameter analyzer is provided at the water outlet of the sedimentation tank (3); The water inlet of the sedimentation tank (3) is connected to the second flocculation zone (301), the outlet of the second flocculation zone (301) is connected to the inlet of the second transition zone (302), the outlet of the second transition zone (302) is connected to the inlet of the second inclined tube sedimentation tank (303), and the other end of the second inclined tube sedimentation tank (303) is provided with a pre-sedimentation tank outlet (304); The second flocculation zone (301) is a grid cyclone reaction tank, and six sedimentation flocculation zones are arranged in an S-shape inside the second flocculation zone (301), including a flocculation zone B1 (301a), a flocculation zone B2 (301b), a flocculation zone B3 (301c), a flocculation zone B4 (301d), a flocculation zone B3 (301e) and a flocculation zone B6 (301f) connected in sequence, wherein the areas of the flocculation zone B1 (301a), the flocculation zone B4 (301d) and the flocculation zone B3 (301e) (201e) are consistent, and the areas of the flocculation zone B2 (301b), the flocculation zone B3 (301c) and the flocculation zone B6 (301f) are consistent; The second inclined tube sedimentation tank (303) includes a second clear water area, a second inclined tube area and a second water distribution area in sequence, wherein the parameters of the inclined tube area are: length 1m, side distance 33mm, tube thickness 0.4mm, and horizontal inclination angle 60°.

8. A method for recycling production wastewater, characterized by: The method comprises a production wastewater reuse treatment simulation device as claimed in any one of claims 1 to 7, wherein the steps are as follows: Step 1: Mix the sludge water and backwash water in a ratio of 4:1, and then mix them with the raw water in a certain ratio in the mixing tank (1); Step 2: detecting water quality data in the mixing tank (1) and the sedimentation tank (3) by using a first multi-parameter analyzer and a second multi-parameter analyzer; Step 3: Adjust the amount of coagulant added in the solution tank (5) according to the data in step 2, and add it into the sedimentation tank (3) or pre-sedimentation tank (2) through the dosing pipe (5a). Step 4: Determine the mixing ratio of the recycled sludge water and backwash water with the raw water and the amount of coagulant added.

9. The process for recycling production wastewater according to claim 8, wherein: The backwash water sampling method in step 1 is: During the filter backwash period, water samples are collected at the water outlet every 1 minute. The backwash period lasts for 12 minutes. The 12 water samples obtained are combined to obtain the backwash water test sample. The sludge water sampling method is: water samples are collected directly at the sludge tank outlet.

10. The method for recycling production wastewater according to claim 8, characterized in that: In step 3, the dosage of coagulant is determined by the drug saving rate. Chemical saving rate (%) = (optimal raw water dosage - optimal mixed water dosage) / optimal raw water dosage × 100% In the formula, the optimal dosage unit for raw water and mixed water is mg / L.

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