Automatic sludge discharge method for water purification plant

Abstract

A kind of automatic sludge discharge method of water purification plant, it is characterized in that, including the following steps:1: construct automatic sludge discharge system;2: mud amount distribution ratio calculation: according to sludge discharge total quantity data and the sludge discharge amount data of each sludge discharge valve, calculate sludge discharge total quantity in each sedimentation tank mud amount distribution ratio;3: construct automatic sludge discharge model: according to the operation data of automatic sludge discharge system, construct automatic sludge discharge model;4: real-time calculation current mud amount: the automatic sludge discharge model real-time calculation current sludge discharge total quantity data in automatic sludge discharge system, then combine mud amount distribution ratio calculation obtains current mud amount data in each sedimentation tank;5: automatic sludge discharge: when the current mud amount data in certain sedimentation tank calculated by automatic sludge discharge model reaches preset sludge discharge mud amount threshold, start sludge discharge.Effect: can guarantee water quality under the premise, try to optimize the sludge discharge time and sludge discharge cycle of each sludge discharge port, reduce sludge discharge water consumption, reduce sludge discharge water cost.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, in particular to an automatic sludge discharge method for a water purification plant. Background Art

[0002] The water resources of the water purification plant come from the direct extraction of river water, which contains a large amount of sediment. Therefore, in the process of water quality treatment, the water purification plant first needs to discharge the sediment in the raw water and meet the sediment discharge standards.

[0003] During the sludge discharge process, the sludge water in the sludge bucket at the bottom of the sedimentation tank is generally discharged through the sludge discharge valve by the deadweight of the water in the sedimentation tank. The control of the sludge discharge time and the sludge discharge cycle is very important. If the sludge discharge time is too short or the sludge discharge cycle is too long, insufficient sludge discharge will occur, affecting the effluent water quality. If the sludge discharge time is too long or the sludge discharge cycle is too short, a large amount of water resources will be wasted, and the sludge discharge cost will increase.

[0004] Disadvantages of existing technology: mud discharge time and mud discharge cycle are difficult to control, and mud discharge cost is high. Summary of the Invention

[0005] The present invention provides an automatic sludge discharge method for a water purification plant, which can optimize the sludge discharge time and sludge discharge cycle of each sludge discharge port as much as possible under the premise of ensuring water quality, reduce the water consumption for sludge discharge, and reduce the water cost for sludge discharge.

[0006] To achieve the above-mentioned object, the present invention provides an automatic sludge discharge method for a water purification plant, the key of which is to include the following steps:

[0007] Step 1: Construct an automatic mud discharge system: The automatic mud discharge system includes a grid water distribution well and M groups of reaction sedimentation tanks;

[0008] Step 2: Calculate the mud volume distribution ratio: Test the automatic mud discharge system, calculate the total amount of mud discharge data based on the inlet water quality data, outlet water quality data and water intake data of the automatic mud discharge system, and calculate the mud volume distribution ratio of the total amount of mud discharge in each sedimentation tank based on the mud discharge volume data of each mud discharge valve;

[0009] Step 3: Build an automatic mud discharge model: Based on the operating data of the automatic mud discharge system, build an automatic mud discharge model, and combine the mud water turbidity data to optimize the mud discharge time and cycle, and reduce the amount of water used for mud discharge;

[0010] Step 4: Real-time calculation of current mud volume: Using a detection device to measure the inlet water quality data, outlet water quality data and intake water volume data of the automatic mud discharge system in real time, and transmit the data to the automatic mud discharge model. The automatic mud discharge model calculates the current total amount of mud discharged in the automatic mud discharge system in real time, and then calculates the current mud volume data in each sedimentation tank based on the mud volume distribution ratio;

[0011] Step 5: Automatic sludge discharge: when the current sludge amount data of a certain sedimentation tank calculated by the automatic sludge discharge model reaches the preset sludge discharge amount threshold, an order is given to the controller, which controls the sludge discharge equipment of the sedimentation tank to open and start sludge discharge; the sludge discharge equipment completes sludge discharge within the set sludge discharge time and then finishes.

[0012] Through the above design, an automatic sludge discharge system is constructed and tested, and then an automatic sludge discharge model is constructed according to the test data, and the sludge discharge time and sludge discharge cycle of each sludge discharge port are continuously optimized under the premise of ensuring water quality, thereby reducing the amount of sludge discharge water and the cost of sludge discharge water.

[0013] As preferred: in the step 1, the water inlet of the grid water distribution well is connected with the water supply pump house through the raw water supply pipe, the water outlet of the grid water distribution well is communicated with the water inlet of the first group of reaction sedimentation tanks through the dosing room, the M groups of reaction sedimentation tanks have consistent structures and are connected in sequence, and the water outlet of the Mth group of reaction sedimentation tanks is connected with the water storage tank.

[0014] As preferred: the reaction sedimentation tank is a hole chamber cyclone flocculation inclined pipe sedimentation tank, or a grid flocculation inclined pipe sedimentation tank, or a combination of the two.

[0015] Each group of hole chamber cyclone flocculation inclined pipe sedimentation tanks is composed of a hole chamber cyclone flocculation tank at the front and an inclined pipe sedimentation tank at the rear, and each group of grid flocculation inclined pipe sedimentation tanks is composed of a grid flocculation tank at the front and an inclined pipe sedimentation tank at the rear.

[0016] Through the above design, the hole chamber cyclone flocculation tank is used to strengthen stirring through cyclone and fine hole perforation technology, promote the aggregation and sedimentation of coagulant particles, the inclined pipe sedimentation tank is used for solid-liquid separation, and the grid flocculation tank is used to capture suspended matter, sediment and organic matter from the suspended pollutants using a grid and separate them from the water, further, the suspended matter and sediment can be collected in the tank and deposited at the bottom to form sediment, so as to achieve the purpose of purifying water quality.

[0017] As preferred: the dosing amount of the dosing room is dynamically adjusted according to the change of raw water turbidity. It can effectively avoid the situation that too much dosing causes faster accumulation of sludge in front and less sludge in rear, and too little dosing causes slower accumulation of sludge in front and more sludge in rear.

[0018] As preferred: in the step 1, at least two rotary screen machines are arranged in the grid water distribution well. The rotary screen machine is used to remove floating matter greater than 5 mm in the raw water.

[0019] As preferred: in the step 2, the calculation formula of the total sludge discharge amount is as follows:

[0020] f(x)=(x-x1)×B

[0021] Among them, x represents the current inlet water quality data, x1 represents the current outlet water quality data; B represents the water intake data at that time;

[0022] The calculation formula for the mud distribution ratio is as follows:

[0023]

[0024]

[0025] Among them, f(η n ) represents the proportion of sludge discharge from the nth sedimentation tank, N represents the total number of sedimentation tanks, x n represents the amount of mud in the mud water discharged from the nth sedimentation tank, t represents the mud discharge time, Q n The amount of sludge water discharged from the nth sedimentation tank, D represents the diameter of the mud discharge pipe, and υ represents the flow velocity.

[0026] Preferably, in step 4, the detection device includes but is not limited to a turbidity meter and a flow rate sensor. The turbidity meter is used to measure the water quality data of the inlet and outlet water, and the flow rate sensor is used to calculate the water intake data and the mud discharge data.

[0027] Preferably, in step 5, the mud discharge device is either a pool bottom valve or a rotary angle-sweeping mud scraper, which can be selected according to actual use.

[0028] The beneficial effects of the present invention are: being able to optimize the mud discharge time and mud discharge cycle of each mud discharge port as much as possible under the premise of ensuring water quality, reducing the mud discharge water consumption and lowering the mud discharge water cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall process of the present invention;

[0030] Figure 2 It is a simplified structural diagram of the present invention;

[0031] Figure 3 This is a configuration diagram of the pre-sedimentation tank and sedimentation tank in the embodiment. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific examples. The following examples or drawings are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0033] like Figure 1 As shown: A method for automatic sludge discharge in a water purification plant, the key of which is to include the following steps:

[0034] Step 1: Construct an automatic mud discharge system: The automatic mud discharge system includes a grid water distribution well and M groups of reaction sedimentation tanks;

[0035] Step 2: Calculate the mud volume distribution ratio: Test the automatic mud discharge system, calculate the total amount of mud discharge data based on the inlet water quality data, outlet water quality data and water intake data of the automatic mud discharge system, and calculate the mud volume distribution ratio of the total amount of mud discharge in each sedimentation tank based on the mud discharge volume data of each mud discharge valve;

[0036] Step 3: Build an automatic mud discharge model: Based on the operating data of the automatic mud discharge system, build an automatic mud discharge model, and combine the mud water turbidity data to optimize the mud discharge time and cycle, and reduce the amount of water used for mud discharge;

[0037] Step 4: Real-time calculation of current mud volume: Using a detection device to measure the inlet water quality data, outlet water quality data and intake water volume data of the automatic mud discharge system in real time, and transmit the data to the automatic mud discharge model. The automatic mud discharge model calculates the current total amount of mud discharged in the automatic mud discharge system in real time, and then calculates the current mud volume data in each sedimentation tank based on the mud volume distribution ratio;

[0038] Step 5: Automatic mud discharge: When the current mud volume data in a sedimentation tank calculated by the automatic mud discharge model reaches the preset mud discharge volume threshold, a command is issued to the controller, and the controller controls the mud discharge equipment of the sedimentation tank to open and start mud discharge; the mud discharge equipment completes the mud discharge within the set mud discharge time.

[0039] like Figure 2 As shown: in the step 1, the water inlet of the grid water distribution well is connected to the water supply pump room through the raw water pipe, and the water outlet of the grid water distribution well is connected to the water inlet of the first group of reaction sedimentation tanks through the dosing room. The M groups of reaction sedimentation tanks have the same structure and are connected end to end in sequence. The water outlet of the M group of reaction sedimentation tanks is connected to the water storage tank.

[0040] The dosage of the dosing room is dynamically adjusted according to the change of raw water turbidity. This can effectively avoid the situation where excessive dosage causes faster accumulation of mud in the front section and less mud in the back section, and too little dosage causes slower accumulation of mud in the front section and more mud in the back section.

[0041] In step 2, the calculation formula for the total amount of sludge discharged is as follows:

[0042] f(x)=(x-x1)×B

[0043] Among them, x represents the current inlet water quality data, x1 represents the current outlet water quality data; B represents the water intake data at that time;

[0044] The calculation formula for the mud distribution ratio is as follows:

[0045]

[0046]

[0047] Among them, f(η n ) represents the proportion of sludge discharge from the nth sedimentation tank, N represents the total number of sedimentation tanks, x n represents the amount of mud in the mud water discharged from the nth sedimentation tank, t represents the mud discharge time, Q n The amount of sludge water discharged from the nth sedimentation tank, D represents the diameter of the mud discharge pipe, and υ represents the flow rate. υ is usually 1.0 to 3.0 m / s at the current pressure. Since it is a mixture of mud and water, the value is 1.5 m / s.

[0048] The present invention is implemented in the water purification plant of Fengshouba Water Plant, including the water source water intake head, gravity water diversion pipe (including water diversion tunnel), water intake pump house and raw water transmission pipe of Fengshouba Water Plant.

[0049] The water purification plant of Fengshouba Water Plant includes water purification structures, backwash pump room, water supply pump room, dosing room, recovery water tank and recovery pump room, production scheduling building and other auxiliary buildings.

[0050] The water purification plant includes the following water purification structures:

[0051] The grid water distribution well is equipped with three rotary screens to remove floating debris larger than 5mm from the raw water. A bottom valve is used for sludge removal. The grid water distribution well has plan dimensions of 12.3 x 14.8, and a depth of 5.75m.

[0052] Porous chamber cyclone flocculation, inclined tube sedimentation tank, two tanks per group, single tank design capacity 50,000 m 3 / d. The flocculation time in the chamber cyclone flocculation tank is 10 minutes, with sludge discharged through a bottom valve. The rising velocity in the inclined tube area of ​​the inclined tube sedimentation tank is 3.0 mm / s, with sludge discharged through a bottom valve. The plan dimensions of each chamber cyclone flocculation and inclined tube sedimentation tank are 43.98 x 22.93. The flocculation tank is 5.65 meters deep, the inlet reaction tank is 5.65 meters deep, and the sedimentation tank is 5.25 meters deep.

[0053] Grid flocculation inclined tube sedimentation tank, two tanks per group, single tank design capacity 50,000 m 3 / d. The grid flocculation tank has a flocculation time of 15 minutes, with sludge discharged via a bottom valve. The inclined tube sedimentation tank has an upward flow velocity of 2.2 mm / s in the inclined tube area, and uses a rotary angle-sweeping scraper for sludge removal. The plan dimensions of each grid flocculation and inclined tube sedimentation tank are 43.98 x 28.65 m, with a flocculation tank depth of 5.65 m and a sedimentation tank depth of 5.35 m.

[0054] The grid water distribution well includes 9 bottom valves for mud discharge, the pre-sedimentation tank includes 44 bottom valves for mud discharge, and the sedimentation tank includes 22 mud discharge valves. The configuration diagram of the pre-sedimentation tank and sedimentation tank is as follows Figure 3 As shown.

[0055] In this embodiment, the orifice chamber cyclone flocculation and inclined tube sedimentation tank are used as the pre-sedimentation tank, and the grid flocculation inclined tube sedimentation tank is used as the sedimentation tank.

[0056] Because the turbidity of the Yangtze River system is low at present, only part of the reaction sedimentation tank is put into operation in the Fengshou Dam Water Plant. According to the field test, the specific test results are described in the following table:

[0057]

[0058] Table 1.1 The sludge discharge time and period of each sludge discharge valve of the pre-sedimentation tank

[0059]

[0060]

[0061] Table 1.2 The sludge discharge time and period of each sludge discharge valve of the pre-sedimentation tank

[0062]

[0063] Table 1.3 The sludge discharge time and period of each sludge discharge valve of the pre-sedimentation tank

[0064]

[0065] Table 2 The sludge discharge time and period of each sludge discharge valve of the sedimentation tank

[0066] According to the test results, the original design data is that the sludge discharge time of the valve at the bottom of the reaction zone of the reaction sedimentation tank is 30s, the sludge discharge time of the valve at the bottom of the sedimentation zone is 10s, and the sludge discharge water volume of each series is 1000m 3 / d. The Fengshou Dam Water Plant has 6 series at present, and the annual sludge discharge water volume is Q1=1000×365×6=2190000m 3 .

[0067] After the test of the automatic sludge discharge method of the water plant, the annual sludge discharge water volume is calculated as Q2=5862734m 3 .

[0068] The annual sludge discharge water volume saved is:

[0069] △Q=Q1-Q2=2190000-5862734=1,603,727(m 3 )

[0070] The proportion of sludge discharge saved is:

[0071]

[0072] In summary, the present invention not only improves the water production efficiency of the water purification plant, but also reduces the amount of water used for sludge discharge and the consumption of water treatment materials while ensuring water quality requirements, thereby reducing the operating costs of the water purification plant.

[0073] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for automatic sludge discharge in a water purification plant, characterized in that: The following steps are involved: Step 1: Construct an automatic mud discharge system: The automatic mud discharge system includes a grid water distribution well and M groups of reaction sedimentation tanks; Step 2: Calculate the mud volume distribution ratio: Test the automatic mud discharge system, calculate the total amount of mud discharge data based on the inlet water quality data, outlet water quality data and water intake data of the automatic mud discharge system, and calculate the mud volume distribution ratio of the total amount of mud discharge in each sedimentation tank based on the mud discharge volume data of each mud discharge valve; Step 3: Build an automatic mud discharge model: Based on the operating data of the automatic mud discharge system, build an automatic mud discharge model, and combine the mud discharge water turbidity data to optimize the mud discharge time and cycle, and reduce the amount of mud discharged; Step 4: Real-time calculation of current mud volume: Using a detection device to measure the inlet water quality data, outlet water quality data and intake water volume data of the automatic mud discharge system in real time, and transmit the data to the automatic mud discharge model. The automatic mud discharge model calculates the current total amount of mud discharged in the automatic mud discharge system in real time, and then calculates the current mud volume data in each sedimentation tank based on the mud volume distribution ratio; Step 5: Automatic mud discharge: When the current mud volume data in a sedimentation tank calculated by the automatic mud discharge model reaches the preset mud discharge volume threshold, a command is issued to the controller, which controls the mud discharge device of the sedimentation tank to open and start mud discharge. The mud discharge device completes the mud discharge within the set mud discharge time; The calculation formula for the total amount of sludge discharged is as follows: f(x)=(x-x1)×B Among them, x represents the current inlet water quality data, x1 represents the current outlet water quality data; B represents the water intake data at that time; The calculation formula for the mud distribution ratio is as follows: Among them, f(η n ) represents the proportion of sludge discharge from the nth sedimentation tank, N represents the total number of sedimentation tanks, x n represents the amount of mud in the mud water discharged from the nth sedimentation tank, t represents the mud discharge time, Q n The amount of sludge water discharged from the nth sedimentation tank, D represents the diameter of the mud discharge pipe, and υ represents the flow velocity.

2. The automatic sludge discharge method for a water purification plant according to claim 1, characterized in that: In step 1, the water inlet of the grid water distribution well is connected to the water supply pump room through the raw water pipe, and the water outlet of the grid water distribution well is connected to the water inlet of the first group of reaction sedimentation tanks through the dosing room. The M groups of reaction sedimentation tanks have the same structure and are connected end to end in sequence. The water outlet of the M group of reaction sedimentation tanks is connected to the water storage tank.

3. The automatic sludge discharge method for a water purification plant according to claim 2, characterized in that: The reaction sedimentation tank is either a chamber cyclone flocculation inclined tube sedimentation tank; or a grid flocculation inclined tube sedimentation tank; or a combination of the two.

4. The automatic sludge discharge method for a water purification plant according to claim 2, characterized in that: The dosage of the dosing room is dynamically adjusted according to the change of raw water turbidity.

5. The automatic sludge discharge method for a water purification plant according to claim 1, characterized in that: In step 1, at least two rotary screen machines are provided in the grid water distribution well.

6. The automatic sludge discharge method for a water purification plant according to claim 1, characterized in that: In step 4, the detection device includes but is not limited to a turbidity meter and a flow rate sensor.

7. The automatic sludge discharge method for a water purification plant according to claim 1, characterized in that: In step 5, the mud discharge equipment adopts either a pool bottom valve or a rotary sweeping angle scraper.

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