A method and device for treating pulp wastewater in organosilicon production industry

Abstract

The present invention relates to the field of sewage treatment, and in particular to a method and device for treating pulp wastewater in the organosilicon production industry, wherein the wastewater is subjected to sedimentation pretreatment to remove silicon powder in the wastewater, and then the pH is adjusted to 6.5-8.5 in batches, and then a membrane device is used for mud-water separation, and the obtained sludge is dehydrated to obtain sludge with a copper taste of more than 30%, and the obtained water can also meet the "Comprehensive Sewage Discharge Standard" (GB8978-1996) after being treated by the membrane device. The advantages of the present invention are that while ensuring that the pulp wastewater in the organosilicon industry meets the discharge standards, silicon powder, heavy metals Cu, Zn, etc. in the sewage are recovered, achieving a win-win situation for the economy and the environment.

Description

Technical Field

[0001] The invention relates to the field of sewage treatment, and in particular to a method and device for treating pulp wastewater in the organosilicon production industry. Background Art

[0002] Waste slurry of organic silicon, referred to as slurry, refers to a liquid-solid mixture with fluidity obtained by wet dust removal during the synthesis of methylchlorosilane monomers. The material accounts for about 2% of the mass fraction of the mixed monomers, and the liquid-solid mass ratio is about 5:1. The liquid phase is mainly high-boiling substances, and the solid phase is mainly suspended silicon powder, high-content copper and other metals. If these materials are exposed to the air, they will burn and (or) form strong acid mist and liquid. Therefore, if they are directly discharged, they will cause serious pollution to the environment and must be harmlessly treated. The main components of the slurry are catalysts, silicon powder and some high-boiling substances. Generally, the high-boiling substances are extracted by sedimentation methods such as gravity sedimentation and centrifugal sedimentation. Then, the high-boiling substances utilization process mentioned above is used to produce monosilane by hydrogen chloride cracking. The remaining high-boiling substances residue, because it contains chlorine, will hydrolyze in the air to produce hydrogen chloride, which pollutes the air. Therefore, the residue is generally hydrolyzed in a hydrolysis kettle with concentrated sulfuric acid, and the generated hydrogen chloride is recovered. The remaining reaction products are separated into solid and liquid. The residue after hydrolysis and dechlorination no longer pollutes the environment and can be sold to brick and tile factories. The liquid phase is impregnated with acid or left for a long time to oxidize copper and recover copper. The remaining waste liquid is sent to the sewage station for treatment. The waste liquid has the characteristics of high suspended matter (SS 500mg / L), strong acidity (pH1~2), and heavy metals (Cu, Zn).

[0003] At present, there are few treatment processes for this waste liquid, and there is no dedicated device for treating this waste liquid. Therefore, domestic wastewater treatment plants currently mix this wastewater with other water and discharge it for comprehensive treatment. The waste residue or sludge produced by the wastewater will cause secondary pollution due to the large amount of heavy metals contained in it, and the heavy metal resources cannot be recovered, resulting in a waste of resources. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a method for treating pulp wastewater in the organosilicon production industry, which can transform copper and zinc ions in the wastewater into sludge containing heavy metals such as copper and zinc, separate the mud and water through a membrane separation system, and the effluent meets the discharge standards. It can also recover silicon powder, heavy metals Cu, Zn, etc. in the wastewater, thereby achieving a win-win situation for the economy and the environment.

[0005] One aspect of the present invention is to provide a method for treating pulp wastewater in the organosilicon production industry, comprising the following steps:

[0006] (1) Pre-treatment by sedimentation: The slurry wastewater from the organosilicon production industry is transferred to a sedimentation tank, and the sedimentation time is controlled at 9 to 12 hours. After the concentration of suspended solids in the supernatant is detected to be below 50 mg / L, the sludge and water are separated to obtain sludge and wastewater a; the sludge is dehydrated to obtain silicon powder sludge;

[0007] (2) First pH adjustment: the wastewater a obtained in step (1) is transferred to the primary reaction tank, and the pH of the wastewater a in the tank is adjusted to 4.0-5.0 by adding chemicals to obtain wastewater b;

[0008] (3) Second pH adjustment: The wastewater b obtained in step (2) is transferred to the secondary reaction tank, and the pH is adjusted to 6.5-8.5 to obtain wastewater c;

[0009] (4) Mud-water separation: Wastewater c is subjected to mud-water separation using a membrane assembly, and the resulting sludge is dehydrated to obtain copper-rich sludge.

[0010] After many experiments, the applicant found that in step (3), a pH in the range of 6.5 to 8.5 can produce heavy metal precipitation and is beneficial to the membrane assembly for mud-water separation.

[0011] Preferably, the membrane in the membrane assembly is an ultrafiltration membrane or a microfiltration membrane.

[0012] In the present invention, the dosing involved in step (2) and step (3) is the addition of a pH regulator; the wastewater c in step (3) is obtained by adding a drug to the wastewater b to adjust the pH, and the pH regulator added to the wastewater c and the wastewater b may be in a completely mixed state, an incompletely mixed state, or both; when a completely mixed state is required, the implementation scheme involved includes but is not limited to: ① adding the drug to the wastewater in the secondary reaction tank, and stopping the dosing after the pH of the wastewater reaches a predetermined value of 6.5 to 8.5; ② calculating the amount of drug required to adjust the pH to 6.5 to 8.5 based on the pH value and water volume of the wastewater b and adding the drug; the incompletely mixed state can avoid the generation of a large amount of heavy metal hydroxides, and the implementation scheme involved may be: calculating the amount of drug required to adjust the pH to 6.5 to 8.5 based on the pH value and water volume of the wastewater b and adding the drug, and then quickly transferring the wastewater to the next reaction tank.

[0013] As one aspect of the above scheme, the second pH adjustment in step (3) and the mud-water separation in step (4) are operated in the same tank. Specifically, the membrane assembly in step (4) is arranged in the secondary reaction tank. The present invention also provides a preferred mode of the scheme, wherein the secondary reaction tank is provided with an aeration device, and the aeration device can stir the water body. More preferably, the aeration volume of the aeration device is 200-300 L / min. The applicant has found that excessive aeration volume will lead to violent stirring, and the precipitated flocs will be broken, which is not conducive to mud-water separation. However, too small aeration volume will lead to slow reaction and insufficient reaction. An aeration volume of 200-300 L / min has a better effect.

[0014] Preferably, the primary reaction tank in step (2) is provided with an aeration device, and the aeration device can stir the water body so that the drug solution and wastewater a react more fully; more preferably, the aeration volume of the aeration device is 200 to 300 L / min.

[0015] As another aspect of the above scheme, the second pH adjustment in step (3) and the mud-water separation and sub-tank operation in step (4) specifically include the following steps:

[0016] (1) Pre-treatment by sedimentation: The slurry wastewater from the organosilicon production industry is transferred to a sedimentation tank, and the sedimentation time is controlled at 9 to 12 hours. After the concentration of suspended solids in the supernatant is detected to be below 50 mg / L, the sludge and water are separated to obtain sludge and wastewater a; the sludge is dehydrated to obtain silicon powder sludge;

[0017] (2) First pH adjustment: the wastewater a obtained in step (1) is transferred to the primary reaction tank, and the pH of the wastewater a in the tank is adjusted to 4.0-5.0 by adding chemicals to obtain wastewater b;

[0018] (3) Second pH adjustment: The wastewater b obtained in step (2) is transferred to the secondary reaction tank, and the amount of drug required to adjust the pH to 6.5-8.5 is quickly added to obtain wastewater c, which is quickly transferred to the tertiary reaction tank;

[0019] (4) Mud-water separation: A membrane assembly is provided in the tertiary reaction tank, and the wastewater c is further mixed in the tertiary reaction tank, and the mud-water separation is performed through the membrane assembly. The obtained sludge is dehydrated to obtain copper-rich sludge.

[0020] Preferably, the primary reaction tank in step (2) is provided with an aeration device, which can stir the water body so that the liquid medicine and wastewater a react more fully; more preferably, the aeration volume of the aeration device in step (2) is 200 to 300 L / min.

[0021] Preferably, the secondary reaction tank in step (3) is provided with an aeration device, which can stir the water body to prevent the precipitation and aggregation of hydroxides; more preferably, the aeration volume of the aeration device in step (3) is 200 to 300 L / min.

[0022] Preferably, the three-stage reaction tank in step (4) is provided with an aeration device, which can stir the water body, and the aeration volume is 300-400 L / min. The applicant has found that too much aeration volume will lead to violent stirring, and the precipitated flocs will be broken up, which is not conducive to mud-water separation. While too little aeration volume will lead to slow reaction and incomplete reaction.

[0023] Another aspect of the present invention is to provide the slurry wastewater treatment device of the silicone industry, including a primary reaction tank, a secondary reaction tank, a drug storage tank, a tertiary reaction tank, a sludge tank and an equipment room; the equipment room, the drug storage tank and the tertiary reaction tank are arranged in an "H" shape from west to east, a sludge tank is arranged to the north of the drug storage tank, and a primary reaction tank and a secondary reaction tank are arranged in sequence from west to east to the south of the drug storage tank, and a membrane component is arranged inside the tertiary reaction tank.

[0024] Preferably, the primary reaction tank, the secondary reaction tank, the drug storage tank, the tertiary reaction tank, the sludge tank and the equipment room are rectangular in shape, wherein the partition walls on the four sides of the tertiary reaction tank and the sludge tank are provided with slopes.

[0025] Preferably, the primary reaction tank is provided with a gas branch pipe 1 and a dosing pipe 1; an aeration device is also provided in the primary reaction tank, and the gas branch pipe 1 is connected to the aeration device; a water inlet pipe is connected to the west partition wall of the primary reaction tank;

[0026] The secondary reaction tank is provided with a second gas branch pipe and a second dosing pipe; an aeration device is provided in the secondary sedimentation tank, and the second gas branch pipe is connected to the aeration device; a drainage pipe is provided on the partition wall on the east side of the secondary reaction tank;

[0027] A gas branch pipe 3 is arranged inside the three-stage reaction pool; an aeration device is arranged inside the three-stage reaction pool, and the gas branch pipe 3 is connected to the aeration device; a sludge discharge pipe 1 is arranged on the partition wall adjacent to the sludge pool on the west side of the three-stage reaction pool, and a sludge pump is arranged at the bottom of the three-stage reaction pool, and the sludge pump is connected to the sludge discharge pipe 1;

[0028] A drug dispensing pipe is arranged on the west partition wall of the drug storage tank; a second mud discharge pipe is arranged on the west partition wall of the sludge tank, and the second mud discharge pipe is connected to the sludge dewatering machine;

[0029] The equipment room is provided with a sludge dewatering machine, a fan, a dosing pump, a dosing pump and a water production pump in sequence from north to south; the sludge dewatering machine is connected to the sludge discharge pipe 2 through a pipeline; the fan is connected to the air supply pipe, and the air supply pipe is provided with a gas supply branch pipe 1, a gas supply branch pipe 2 and a gas supply branch pipe 3; the dosing pump is arranged on the dosing pipe 1, and the two ends of the dosing pipe 1 are respectively connected to the drug storage tank and the primary reaction tank; the dosing pump is arranged on the dosing pipe 2, and the two ends of the dosing pipe 2 are respectively connected to the drug storage tank and the secondary reaction tank; the water production pump is arranged on the outlet pipe, and one end of the outlet pipe is connected to the membrane assembly, and the other end is connected to the clear water tank.

[0030] Preferably, the device further comprises a control system, which comprises a pH monitoring module, a dosing pump control module, a water production pump control module, and a fan control module, and controls the operation of the pulp and slag wastewater treatment device in the following manner:

[0031] S1: The pH monitoring module monitors the pH in the primary reaction tank. When the pH reaches the set value P0, the dosing pump stops running;

[0032] S2: Calculate the dosage required for the secondary reaction tank as Q0 based on the water volume, and control the second dosing pump to stop running after the dosage reaches Q0;

[0033] S3: By setting the water production cycle and intermittent time, the water production pump runs for T1 time every T0 time;

[0034] S4: The fan operation is controlled by setting the fan operation cycle, and the fan runs for T3 time every T2 time.

[0035] S4: Set the backwash cycle to T4. The system will backwash after every T4 time. Under the action of the water production pump, clean water will enter the membrane assembly from the clean water tank to flush the membrane assembly.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention discloses a method for treating pulp wastewater in the organosilicon production industry. The wastewater is subjected to sedimentation pretreatment to remove silicon powder in the wastewater, and then the pH is adjusted to neutral in batches, and then the sludge is separated from the water by a membrane device. The obtained sludge is dehydrated to obtain sludge with a copper taste of more than 30%. The obtained water can also meet the "Comprehensive Wastewater Discharge Standard" (GB8978-1996) after being treated by the membrane device. The advantages of the present invention are that while ensuring that the pulp wastewater in the organosilicon industry meets the discharge standards, the silicon powder, heavy metals Cu, Zn, etc. in the wastewater are recovered, achieving a win-win situation for the economy and the environment.

[0038] 2. The present invention discloses a treatment device for pulp wastewater in the silicone production industry. Each reaction tank and functional area is arranged according to the flow direction of wastewater treatment. The compact structure reduces the space occupied, is beneficial to wastewater treatment, and is beneficial to the layout of aeration and dosing pipelines. It can greatly reduce construction costs and is very practical.

[0039] 3. The device of the present invention can be automated by setting up a control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 : A process flow chart of the method for treating pulp wastewater in the organosilicon production industry according to the present invention;

[0041] Figure 2 : A schematic diagram of the structure of the treatment device for slurry wastewater in the organosilicon production industry according to the present invention; 1-primary reaction tank, 11-water inlet pipe, 12-overflow gap, 2-secondary reaction tank, 22-drain pipe, 3-drug storage tank, 31-drug dispensing pipe, 4-tertiary reaction tank, 41-membrane module, 42-sludge pump, 43-sludge discharge pipe 1, 5-sludge tank, 52-sludge discharge pipe 2, 6-equipment room, 61-sludge dewatering machine, 62-blower, 63-dosing pump 1, 64-water production pump, 65-dosing pump 2, 7-gas transmission pipe, 71-gas transmission branch pipe 1, 72-gas transmission branch pipe 2, 73-gas transmission branch pipe 3, 81-dosing pipe 1, 82-dosing pipe 2, 9-water outlet pipe;

[0042] Figure 3 : Schematic diagram of the control system for pulp wastewater in the organosilicon production industry according to the present invention. DETAILED DESCRIPTION

[0043] The present invention discloses a method and device for treating pulp wastewater in the organosilicon production industry. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It should be particularly pointed out that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The method and device of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0044] In the present invention, unless otherwise specified, the detection methods involved are all conventional detection methods, and unless otherwise specified, the raw materials and equipment involved are common commercial products and can be purchased on the market.

[0045] It should be noted that the slurry wastewater in the organosilicon production industry mentioned in the present invention refers to the wastewater produced after the high-boiling substances in the organosilicon waste slurry are treated. The general characteristics of this wastewater are: high suspended matter (SS about 500 mg / L), strong acidity (pH about 1-2), and high heavy metal content (Cu and Zn).

[0046] In order to further understand the present invention, a method for treating pulp wastewater in the organosilicon production industry provided by the present invention is described in detail below in conjunction with embodiments.

[0047] Example 1: Treatment method for pulp wastewater in organosilicon production industry

[0048] The method for treating pulp wastewater in the organosilicon production industry of the present invention comprises the following steps:

[0049] (1) Pretreatment by sedimentation: The slurry wastewater from the organosilicon production industry is transferred to a sedimentation tank, and the sedimentation time is controlled at 9-12 hours. After the suspended solid concentration (SS) of the supernatant is detected to be below 50 mg / L, the sludge and water are separated to obtain sludge and wastewater a; the sludge precipitated at the bottom is pumped out by a sludge pump, and the sludge is filtered to obtain silicon powder sludge, and the upper wastewater a is treated in the next step.

[0050] (2) First pH adjustment: the wastewater a obtained in step (1) is transferred to the primary reaction tank 1, and the pH of the wastewater a in the tank is adjusted to 4.0-5.0 to obtain wastewater b. The water in the primary reaction tank is stirred by blowing air into the tank through an aeration pipe; the aeration rate is controlled at 200-300 L / min;

[0051] (3) Second pH adjustment: The wastewater b obtained in step (2) is transferred to a secondary reaction tank, and the pH of the wastewater b in the tank is adjusted to 6.5-8.5 to obtain wastewater c. The water in the secondary reaction tank is stirred by blowing air into the tank through an aeration pipe; the aeration rate is preferably 200-300 L / min.

[0052] (4) Mud-water separation: Wastewater c is separated from wastewater by a membrane assembly. The secondary reaction tank is equipped with a membrane assembly, and the membrane of the membrane assembly is an ultrafiltration membrane or a microfiltration membrane. The effluent is tested to meet the "Comprehensive Wastewater Discharge Standard" (GB8978-1996), and the obtained sludge enters the next step;

[0053] (5) The sludge obtained in step (4) is dehydrated to obtain copper-rich sludge. The copper content of the copper-rich sludge is above 30% after testing.

[0054] This process is used to treat pulp wastewater in the silicone production industry. The water quality of the inlet and outlet water is shown in Table 1:

[0055] Table 1: Comparison of water quality of influent and effluent of the process of the present invention

[0056] COD(mg / L) pH Cu(mg / L) Zn(mg / L) Water Intake ～200 ～2 ～200 ～200 Water <100 6～9 <0.5 <1.0

[0057] From the above content, it can be seen that the method for treating pulp wastewater in the silicone production industry of the present invention can transform the copper and zinc ions in the wastewater into sludge containing heavy metals such as copper and zinc, separate the mud and water through a membrane separation system, and discharge the effluent in compliance with the standards. Silicon powder, heavy metals Cu and Zn, etc. in the wastewater can also be recovered, achieving a win-win situation for the economy and the environment.

[0058] Example 2: Treatment method for pulp wastewater in the organosilicon production industry

[0059] The method for treating pulp wastewater in the organosilicon production industry of the present invention comprises the following steps:

[0060] (1) Pretreatment by sedimentation: The slurry wastewater from the organosilicon production industry is transferred to a sedimentation tank, and the sedimentation time is controlled at 9-12 hours. After the suspended solid concentration (SS) in the supernatant is detected to be below 50 mg / L, the sludge and water are separated to obtain sludge and wastewater a; the sludge precipitated at the bottom is pumped out by a sludge pump, and the sludge is filtered to obtain silicon powder sludge, and the upper wastewater a is treated in the next step.

[0061] (2) First pH adjustment: the wastewater a obtained in step (1) is transferred to the primary reaction tank 1, and the pH of the wastewater a in the tank is adjusted to 4.0-5.0 to obtain wastewater b. The water in the primary reaction tank is stirred by blowing air into the tank through an aeration pipe; the aeration rate is controlled at 200-300 L / min;

[0062] (3) Second pH adjustment: The wastewater b obtained in step (2) is transferred to the secondary reaction tank 2, and the pH of the wastewater b in the tank is adjusted to 6.5-8.5 to obtain wastewater c. The water in the secondary reaction tank is stirred by blowing air into the tank through an aeration pipe; the aeration rate is 200-300 L / min.

[0063] (4) Mud and water separation: Wastewater c is transferred to the tertiary reaction tank 4, and the membrane assembly installed in the tank is used for mud and water separation. The membrane of the membrane assembly is an ultrafiltration membrane or a microfiltration membrane, and the aeration volume is 300-400L / min. The effluent is tested to meet the "Comprehensive Wastewater Discharge Standard" (GB8978-1996), and the obtained sludge enters the next step;

[0064] (5) The sludge obtained in step (4) is dehydrated to obtain copper-rich sludge. The copper content of the copper-rich sludge is above 30% after testing.

[0065] Example 3: Silicone industry slurry wastewater treatment device

[0066] Please refer to Figure 2 The slurry wastewater treatment device for the organic silicon industry of the present invention comprises a primary reaction tank 1, a secondary reaction tank 2, a drug storage tank 3, a tertiary reaction tank 4, a sludge tank 5, an equipment room 6, an air pipe 7 for providing stirring for each reaction tank, and a drug adding pipe for adding drugs to each reaction tank;

[0067] The device is rectangular in layout; specifically, the equipment room 6, the drug storage tank 3 and the tertiary reaction tank 4 are arranged in an "H" shape from west to east, a sludge tank 5 is arranged to the north of the drug storage tank 3, and a primary reaction tank 1 and a secondary reaction tank 2 are arranged to the south of the drug storage tank 3 from west to east in sequence; specifically, each reaction tank and functional area is described as follows:

[0068] The primary reaction tank 1 is used to treat wastewater a pre-treated by a sedimentation tank (the sedimentation tank is not shown in the figure, and the sedimentation tank can be set according to the conventional method in the field without special restrictions). The wastewater a undergoes the first pH adjustment in the primary reaction tank 1. The primary reaction tank 1 is rectangular in shape, and a gas branch pipe 71 and a dosing pipe 81 are correspondingly arranged inside the primary reaction tank 1; an aeration device is arranged in the primary reaction tank 1 (not shown in the figure, and there are no special requirements for the selection and installation of the aeration device, and it can be arranged according to the conventional method in the field). The gas branch pipe 71 is connected to the aeration device; the west partition wall of the primary reaction tank 1 is connected to a water inlet pipe 11;

[0069] The secondary reaction tank 2 is used to dosing the wastewater b transferred into the primary reaction tank 1 for the second time. The secondary reaction tank 2 is rectangular in shape, and its volume is equivalent to or appropriately increased from the primary reaction tank 1. The secondary reaction tank 2 is provided with a second gas branch pipe 72 and a second dosing pipe 82; an aeration device is provided in the secondary sedimentation tank 2 (not shown in the figure, there are no special requirements for the selection and installation of the aeration device, and it can be set according to the conventional methods in the field). The second gas branch pipe 72 is connected to the aeration device; a drainage pipe 22 is provided on the partition wall on the east side of the secondary reaction tank 2, and the drainage pipe 22 is used to discharge the wastewater c into the third reaction tank 4; in order to increase the drainage speed, preferably, the secondary reaction tank 2 is also provided with a water pump, which is connected to the drainage pipe 22 to quickly discharge the wastewater c into the tertiary reaction tank 4. Preferably, in order to transfer wastewater into the secondary reaction tank 2, it can be selected to transfer through overflow or water pump. Preferably, an overflow gap 12 is provided on the partition wall between the primary reaction tank 1 and the secondary reaction tank 2;

[0070] The partition walls on the four sides of the tertiary reaction tank 4 are provided with slopes, a membrane assembly 41 is provided inside the tertiary reaction tank 4, and a gas branch pipe 3 73 is provided accordingly; an aeration device is provided inside the tertiary reaction tank 4 (the purpose of the aeration device is to stir and prevent membrane fouling) (not shown in the figure, there are no special requirements for the selection and installation of the aeration device, and it can be set up according to the conventional methods in the field), and the gas branch pipe 3 73 is connected to the aeration device; a sludge pipe 1 43 is provided on the partition wall adjacent to the sludge tank 5 on the west side of the tertiary reaction tank 4, and a sludge pump 42 is provided at the bottom of the tertiary reaction tank 4, and the sludge pump 42 is connected to the sludge pipe 1 43 to pump sludge into the sludge tank 5.

[0071] The medicine storage tank 3 is rectangular in shape, and a medicine dispensing pipe 31 is arranged on the west partition wall of the medicine storage tank 3. The medicine storage tank 3 is used to store the prepared medicine solution. In the present invention, the medicine solution is usually a pH regulating liquid. According to the strong acidity of the wastewater of the present invention, the medicine solution is a conventional alkaline liquid, including but not limited to NaOH, KOH and ammonia water;

[0072] The sludge pool 5 is used to store sludge. The partition walls on the four sides of the sludge pool 4 are provided with slopes. A sludge discharge pipe 52 is provided on the west partition wall of the sludge pool 5. The sludge discharge pipe 52 is connected to a sludge dewatering machine 61. After the sludge is dehydrated, copper-enriched sludge is obtained.

[0073] The equipment room 6 is provided with a sludge dewatering machine 61, a fan 62, a dosing pump 63, a dosing pump 65 and a water production pump 64 in sequence from north to south; the sludge dewatering machine 61 is used to dewater the sludge in the sludge tank 5, the fan 62 is connected to the air pipe 7, and the air pipe 7 is provided with a gas branch pipe 1 71, a gas branch pipe 2 72 and a gas branch pipe 3 73; wherein the gas branch pipe 1 71 is connected to the aeration device at the bottom of the primary reaction tank 1; the gas branch pipe 2 72 is connected to the aeration device at the bottom of the secondary reaction tank 2; the gas branch pipe 3 73 is connected to the aeration device at the bottom of the tertiary reaction tank 2; The aeration device at the bottom of the pool 4; the dosing pump 63 is arranged on the dosing pipe 81, and the two ends of the dosing pipe 81 are respectively connected to the drug storage tank 3 and the primary reaction tank 1; the dosing pump 65 is arranged on the dosing pipe 82, and the two ends of the dosing pipe 82 are respectively connected to the drug storage tank 3 and the secondary reaction tank 2; the water production pump 64 is arranged on the outlet pipe 9, one end of the outlet pipe 9 is connected to the membrane assembly 41, and the other end leads to the clean water tank (not marked in the figure, the function of the clean water tank is to collect the clean water separated by the membrane assembly and provide a water source for backwashing of the membrane assembly).

[0074] Example 4: Operation control of slurry wastewater treatment device in the silicone industry

[0075] The automation of the device is realized by setting a control system and a corresponding detection module on the device described in Example 3. Figure 3Specifically, the control system of the present invention includes a pH monitoring module, a dosing pump control module, a water production pump control module, and a fan control module;

[0076] Specifically, the pH monitoring module includes a pH probe, a pH signal acquisition system, and an associated dosing pump control system. The pH signal acquisition system acquires the pH value measured by the probe, and when it reaches the set value, it issues an instruction for the dosing pump to stop dosing.

[0077] Dosing pump control module: The dosing pump control module includes a signal receiver and a switch controller. The signal receiver receives the signal from the pH monitoring module and transmits it to the switch controller to control the start and operation of the dosing pump;

[0078] Water production pump control module: The water production pump control module includes a switch controller for setting the operation cycle and a signal receiver. The equipment produces water according to the set cycle. The signal receiver is connected to the liquid level gauge in the third reaction tank. When the liquid level is low, no water is produced.

[0079] Fan control module: The fan control module includes a switch controller with a set operating cycle for intermittent operation.

[0080] The operation of the equipment is controlled by:

[0081] S1: The pH monitoring module monitors the pH in the primary reaction tank 1. When the pH reaches the set value P0, the dosing pump 63 stops running;

[0082] S2: Calculate the dosage required for the secondary reaction tank 2 as Q0 according to the water volume, and control the dosing pump 265 to stop running after the dosage reaches Q0;

[0083] S3: By setting the water production cycle and the intermittent time, the water production pump 64 runs for T1 time every T0 time;

[0084] S4: The operation of the fan 62 is controlled by setting the operation cycle of the fan 62, and the fan 62 runs for T3 time every T2 time.

[0085] S4: the backwashing cycle is set to T4. The system performs backwashing every T4 time. Clean water enters the membrane assembly 41 from the clean water tank under the action of the water production pump 64 to wash the membrane assembly 41.

[0086] The working principle of the automatic wastewater treatment device is as follows: the wastewater a that has been pre-treated by precipitation to remove silicon powder sludge enters the primary reaction tank 1, the secondary reaction tank 2 and the tertiary reaction tank 4 in turn. After the reaction is complete, it is separated and produced water through the membrane component 41. When the wastewater a passes through the first reaction tank, the dosing pump 1 63 is turned on to add medicine to the first reaction tank 1 through the dosing pipe 1 81. The pH monitoring module monitors the pH value of the wastewater online. After reaching the set value P0, the dosing pump 1 63 stops running, and the wastewater b enters the secondary reaction tank 2. The dosing pump 2 65 on the dosing pipe 2 82 is turned on, and the agent enters the secondary reaction tank 2 through the dosing pump 2 65. The dosing pump 2 65 is turned on according to the set dosing amount Q0. After the secondary dosing is quickly completed, the wastewater c enters the tertiary reaction tank 4 for full reaction to form heavy metal sludge precipitation. Water is produced according to the set water production cycle T0, and mud and water separation is achieved at the same time. The sludge in the tertiary reaction tank 4 is pumped into the sludge tank 5 for storage through the sludge pump 4.

[0087] For the convenience of expression, the descriptions of the directions such as "east", "west", "south", "north", "up", "down", "left", "right", "front", "back", "longitudinal", and "lateral" referred to herein are consistent with the directions of the drawings themselves, but do not limit the structure of the present invention; the specific embodiments of the present invention are described in detail above, but they are only used as examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions made to the present invention are also within the scope of the present invention. Therefore, equivalent changes and modifications made without departing from the spirit and scope of the present invention are all covered within the scope of the present invention.

Claims

1. A method for treating pulp wastewater in the organosilicon production industry, characterized in that: The following steps are involved: (1) Pre-treatment by sedimentation: The slurry wastewater from the organosilicon production industry is transferred to a sedimentation tank, and the sedimentation time is controlled at 9 to 12 hours. After the concentration of suspended solids in the supernatant is detected to be below 50 mg / L, the sludge and water are separated to obtain sludge and wastewater a; the sludge is dehydrated to obtain silicon powder sludge; (2) First pH adjustment: the wastewater a obtained in step (1) is transferred to the primary reaction tank, and the pH of the wastewater a in the tank is adjusted to 4.0-5.0 by adding chemicals to obtain wastewater b; (3) Second pH adjustment: The wastewater b obtained in step (2) is transferred to the secondary reaction tank, and the amount of the drug required to adjust the pH to 6.5-8.5 is calculated based on the pH value and water volume of the wastewater b. The amount of the drug required to adjust the pH to 6.5-8.5 is quickly added to obtain wastewater c, which is quickly transferred to the tertiary reaction tank; (4) Mud-water separation: A membrane assembly is provided in the tertiary reaction tank, and the wastewater c is further mixed in the tertiary reaction tank, and the membrane assembly is used to separate the mud and water, and the obtained sludge is dehydrated to obtain copper-rich sludge; The primary reaction tank of step (2) is provided with an aeration device, and the aeration volume of the aeration device is 200-300 L / min; the secondary reaction tank of step (3) is provided with an aeration device, and the aeration volume of the aeration device is 200-300 L / min; The slurry wastewater treatment device of the organic silicon industry includes a primary reaction tank, a secondary reaction tank, a drug storage tank, a tertiary reaction tank, a sludge tank and an equipment room; the equipment room, the drug storage tank and the tertiary reaction tank are arranged in an "H" shape from west to east, a sludge tank is arranged to the north of the drug storage tank, and a primary reaction tank and a secondary reaction tank are arranged to the south of the drug storage tank from west to east in sequence, and a membrane module is arranged inside the tertiary reaction tank; The primary reaction tank is provided with a gas branch pipe 1 and a dosing pipe 1; an aeration device is also provided in the primary reaction tank, and the gas branch pipe 1 is connected to the aeration device; a water inlet pipe is connected to the west partition wall of the primary reaction tank; The secondary reaction tank is provided with a second gas branch pipe and a second dosing pipe; an aeration device is provided in the secondary reaction tank, and the second gas branch pipe is connected to the aeration device; a drainage pipe is provided on the partition wall on the east side of the secondary reaction tank; A gas branch pipe 3 is arranged inside the three-stage reaction pool; an aeration device is arranged inside the three-stage reaction pool, and the gas branch pipe 3 is connected to the aeration device; a sludge discharge pipe 1 is arranged on the partition wall adjacent to the sludge pool on the west side of the three-stage reaction pool, and a sludge pump is arranged at the bottom of the three-stage reaction pool, and the sludge pump is connected to the sludge discharge pipe 1; A drug dispensing pipe is arranged on the west partition wall of the drug storage tank; a second mud discharge pipe is arranged on the west partition wall of the sludge tank, and the second mud discharge pipe is connected to the sludge dewatering machine; The equipment room is provided with a sludge dewatering machine, a fan, a dosing pump, a dosing pump and a water production pump in sequence from north to south; the sludge dewatering machine is connected to the sludge discharge pipe 2 through a pipeline; the fan is connected to the air supply pipe, and the air supply pipe is provided with a gas supply branch pipe 1, a gas supply branch pipe 2 and a gas supply branch pipe 3; the dosing pump is arranged on the dosing pipe 1, and the two ends of the dosing pipe 1 are respectively connected to the drug storage tank and the primary reaction tank; the dosing pump is arranged on the dosing pipe 2, and the two ends of the dosing pipe 2 are respectively connected to the drug storage tank and the secondary reaction tank; the water production pump is arranged on the outlet pipe, and one end of the outlet pipe is connected to the membrane assembly, and the other end is connected to the clear water tank.

2. The method for treating pulp wastewater in the organosilicon production industry according to claim 1, characterized in that: The membrane in the membrane assembly in step (4) is an ultrafiltration membrane or a microfiltration membrane.

3. The method for treating pulp wastewater in the organosilicon production industry according to claim 1, characterized in that: The three-stage reaction tank in step (4) is provided with an aeration device, and the aeration volume of the aeration device is 300 to 400 L / min.

4. The method for treating pulp wastewater in the organosilicon production industry according to claim 1, characterized in that: The primary reaction tank, the secondary reaction tank, the drug storage tank, the tertiary reaction tank, the sludge tank, and the equipment room are rectangular in shape, wherein the partition walls on the four sides of the tertiary reaction tank and the sludge tank are provided with slopes.

5. A method for treating pulp wastewater in the organosilicon production industry according to claim 4, characterized in that: The device also includes a control system, which includes a pH monitoring module, a dosing pump control module, a water production pump control module, and a fan control module, and controls the operation of the pulp and slag wastewater treatment device in the following manner: S1: The pH monitoring module monitors the pH in the primary reaction tank. When the pH reaches the set value P0, the dosing pump stops running; S2: Calculate the dosage required for the secondary reaction tank as Q0 based on the water volume, and control the second dosing pump to stop running after the dosage reaches Q0; S3: By setting the water production cycle and intermittent time, the water production pump runs for T1 time every T0 time; S4: Control the operation of the fan by setting the fan operation cycle, and the fan runs for T3 time every T2 time; S4: Set the backwash cycle to T4. The system will backwash after every T4 time. Under the action of the water production pump, clean water will enter the membrane assembly from the clean water tank to flush the membrane assembly.

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