CN106587306B

CN106587306B - High-speed coagulation reactor for water supply treatment

Info

Publication number: CN106587306B
Application number: CN201611260881.6A
Authority: CN
Inventors: 王全勇; 韩雯雯; 王新伟; 解宝民
Original assignee: Shandong Huacheng Engineering Technology Co ltd
Current assignee: Shandong Huacheng Engineering Technology Co ltd
Priority date: 2016-12-30
Filing date: 2016-12-30
Publication date: 2023-08-08
Anticipated expiration: 2036-12-30
Also published as: CN106587306A

Abstract

The invention particularly relates to a high-speed coagulation reactor for water supply treatment. The high-speed coagulation reactor for water supply treatment comprises a reactor tank body, a water inlet pipe and a water outlet pipe, wherein an L-shaped feed pipe is arranged at the upper part of the reactor tank body, a stirrer and a turbulent flow cylinder are also arranged in the reactor tank body, and the stirrer is arranged in the center of the reactor tank body and is connected to a motor through a speed reducer; the turbulent flow cylinder is fixed at the top end of the reactor tank body and is arranged between the stirrer and the reactor tank body; the water inlet pipe and the water outlet pipe are respectively embedded on the outer walls of the left side and the right side of the reactor tank body. The high-speed coagulation reactor for water supply treatment can improve the mixing rate, reduce the mixing time, improve the removal rate of coagulating sedimentation on organic matters, further improve the subsequent flocculation, sedimentation and filtration effects, and obviously improve the water quality of effluent after a filter tank; meanwhile, the coagulant consumption can be reduced, the volume of the mixing tank is reduced, and the running cost and engineering construction investment are reduced.

Description

High-speed coagulation reactor for water supply treatment

Technical Field

The invention relates to the technical field of water treatment, in particular to a high-speed coagulation reactor for water treatment.

Background

At present, the turbidity of the effluent of a sedimentation tank of a water purification plant adopting a conventional treatment process in China is mostly 1-3 NTU, and the turbidity of the effluent of a filter tank is generally not more than 1NTU; the turbidity of the effluent of a sedimentation tank of an advanced foreign water purification plant adopting similar process flows is not higher than 1NTU, the turbidity of the effluent of a filter tank is not higher than 0.1NTU, and the standard of direct drinking water can be achieved without advanced treatment. After the membrane filtration advanced treatment is added after the domestic conventional treatment process, the turbidity of the water supply can reach the level not higher than 0.1 NTU. In order to ensure that the quality of the water supply reaches 106 domestic drinking water quality standards newly issued by the nation under the condition of not increasing the running cost, a plurality of water supply treatment technologies are developed from the aspects of pretreatment, strengthening of the conventional process, advanced treatment and the like at home and abroad.

The coagulation process is an indispensable front-end key link in the water treatment process flow, and the quality of the effect often determines the operation condition, the final water outlet quality and the cost of the subsequent process flow, so that the coagulation is one of important research and development fields in the water treatment engineering.

At present, the reinforced coagulation process generally takes the improvement of coagulant performance, the increase of dosage, the prolongation of flocculation time, the adjustment of the hydraulic conditions of a flocculation reactor and the like as main improvement directions, and the optimization research on the mixing, which is the first step of the coagulation process, is less. As a preceding process in the water supply treatment, the degree of mixing of the agents directly affects the subsequent flocculation, precipitation, and filtration effects. Based on this, the present invention provides a high-speed coagulation reactor for water treatment.

Disclosure of Invention

In order to make up the defects of the prior art, the invention provides a high-speed coagulation reactor for water supply treatment with high desulfurization rate.

The invention is realized by the following technical scheme:

a high-speed coagulation reactor for water treatment is characterized in that: the reactor comprises a reactor tank body, a water inlet pipe and a water outlet pipe, wherein an L-shaped feed pipe is arranged at the top of the reactor tank body, and a stirrer and a turbulent flow cylinder are also arranged in the reactor tank body; the turbulent flow cylinder is fixed at the top end of the reactor tank body and is arranged between the stirrer and the reactor tank body; the water inlet pipe and the water outlet pipe are respectively embedded on the outer walls of the left side and the right side of the reactor tank body.

The water inlet pipe is positioned at the bottom of the reactor tank body, and the water outlet pipe is positioned at the upper part of the reactor tank body.

The diameter of the turbulent flow cylinder is 2-3 times of the outer diameter of the stirrer blade, holes are uniformly distributed on the turbulent flow cylinder body, and the aperture ratio is not less than 50%.

The outer diameter of the stirrer blade is 200-400 mm, the blade angle is 5-20 degrees, and the rotation speed of the stirrer is 800-1200 r/min.

The L-shaped feeding pipe is positioned inside the turbulent flow cylinder, and a discharge hole of the L-shaped feeding pipe is positioned at a position 10-30 mm below the stirrer.

The beneficial effects of the invention are as follows: the high-speed coagulation reactor for water supply treatment can improve the mixing rate, reduce the mixing time, ensure that the coagulant and the colloid particles in water are rapidly and uniformly mixed in the shortest time, improve the removal rate of organic matters by coagulating sedimentation, further improve the subsequent flocculation, sedimentation and filtration effects, and ensure that the water quality of the effluent after the filter tank is obviously improved; meanwhile, the coagulant consumption can be reduced, the volume of the mixing tank is reduced, and the running cost and engineering construction investment are reduced.

Drawings

FIG. 1 is a schematic diagram of a high-speed coagulation reactor for water treatment according to the present invention.

FIG. 2 is a schematic view of a sectional structure of a high-speed coagulation reactor A-A for water treatment according to the present invention.

FIG. 3 is a schematic diagram showing the sectional structure of a high-speed coagulation reactor B-B for water treatment according to the present invention.

In the drawing, a reactor 1, a motor 2, a speed reducer 3, a stirrer blade 4, a turbulence barrel 5, a water inlet pipe 6, a water outlet pipe 7 and a dosing pipe 8 are arranged.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the specific embodiments described herein are for the purpose of illustrating the invention only and are not to be construed as limiting the invention.

The high-speed coagulation reactor for water supply treatment comprises a reactor tank body 1, a water inlet pipe 6 and a water outlet pipe 7, wherein an L-shaped feed pipe 8 is arranged at the top of the reactor tank body, a stirrer 4 and a turbulent flow cylinder 5 are also arranged in the reactor tank body 1, and the stirrer 4 is arranged in the center of the reactor tank body 1 and is connected to a motor 2 through a speed reducer 3; the turbulent flow cylinder 5 is fixed at the top end of the reactor tank 1 and is arranged between the stirrer 4 and the reactor tank 1; the water inlet pipe 6 and the water outlet pipe 7 are respectively embedded on the outer walls of the left side and the right side of the reactor tank body 1.

The water inlet pipe 6 is positioned at the bottom of the reactor tank body 1, and the water outlet pipe 7 is positioned at the upper part of the reactor tank body 1.

The diameter of the turbulence tube 5 is 2-3 times of the outer diameter of the blade of the stirrer 4, holes are uniformly distributed on the tube body of the turbulence tube 5, and the aperture ratio is not less than 50%.

The outer diameter of the blades of the stirrer 4 is 200-400 mm, the angles of the blades are 5-20 degrees, and the rotating speed of the stirrer 4 is 800-1200 r/min.

The L-shaped feeding pipe 8 is positioned in the turbulent flow cylinder 5, and a discharge hole of the L-shaped feeding pipe is positioned at a position 10-30 mm below the stirrer 4.

Example 1

The stirrer 4 is installed in a fully immersed type vertical mode, the rotating speed is 960r/min, the outer diameter of the blade is 400mm, and the angle is 15 degrees; the diameter of the turbulence tube 5 is 2 times of the outer diameter of the blade of the stirrer 4, the mesh holes on the turbulence tube 5 are round holes, and the aperture ratio is 70%; the discharge hole of the L-shaped feeding pipe 8 is arranged below the blade of the stirrer 4 by 15mm. The source water mixed by adding the polyaluminium chloride enters a high-speed stirring and mixing reactor, the high-speed stirring equipment is driven by a driving device to stir the water body, the reaction time is 10s, and then the water body enters an original flocculation tank, an original sedimentation tank and an original sand filter tank in sequence.

Example 2

The stirrer 4 is installed in a fully immersed type vertically, the rotating speed is 800r/min, the outer diameter of the blade is 360mm, and the angle is 20 degrees; the diameter of the turbulence tube 5 is 2.5 times of the outer diameter of the blade of the stirrer 4, the mesh holes on the turbulence tube 5 are round holes, and the aperture ratio is 50%; the discharge hole of the L-shaped feeding pipe 8 is arranged below the blade of the stirrer 4 by 10mm. The source water mixed by adding the polyaluminium chloride enters a high-speed stirring and mixing reactor, the high-speed stirring equipment is used for stirring the water body under the driving of a driving device, the reaction time is 8s, and then the water enters an original flocculation tank, an original sedimentation tank and an original sand filter tank in sequence.

Example 3

The stirrer 4 is installed in a fully immersed type vertically, the rotating speed is 1200r/min, the outer diameter of the blade is 200mm, and the angle is 5 degrees; the diameter of the turbulence tube 5 is 3 times of the outer diameter of the blade of the stirrer 4, the mesh holes on the turbulence tube 5 are round holes, and the aperture ratio is 80%; the discharge hole of the L-shaped feeding pipe 8 is arranged below the blade of the stirrer 4 by 30mm. The source water mixed by adding the polyaluminium chloride enters a high-speed stirring and mixing reactor, the high-speed stirring equipment is used for stirring the water body under the driving of a driving device, the reaction time is 5s, and then the water enters an original flocculation tank, an original sedimentation tank and an original sand filter tank in sequence.

The high-speed coagulation reactor for water supply treatment optimizes mixing from two aspects of improving diffusion speed and forming micro vortex diffusion.

1. Increase the diffusion rate

The coagulation effect is closely related to the diffusion speed of the medicament in water. After coagulant is added into raw water, two effects are produced: (1) the coagulant is diffused and mixed in the water; (2) the coagulant is hydrolyzed, and the hydrolysis product acts on the colloid particles to destabilize the colloid particles. Because the rate of hydrolysis and destabilization is far greater than the diffusion rate of the coagulant in water, if the coagulant cannot be mixed rapidly and uniformly in water, colloid particles are rapidly destabilized and large at more positions of the coagulant, and colloid particles lack conditions of large coagulation at the positions of insufficient coagulant, so that colloid particles in water cannot be destabilized uniformly, and the flocculation effect is poor.

The hydrolyzed monomer morphology, e.g., aluminum salts, can be in the range of microseconds (-10) ^-4 s) while some oligomerization and morphology can form within 1s, the charge neutralization coacervation must be completed before the hydrolysis reaction and hydroxide precipitation, thus requiring a short rapid mixing time to mix the coagulant with the colloidal particles in a minimum amount of time. The mixing stage requires intense stirring of the water body so that the coagulant is quickly and uniformly mixed with the water body.

The mixing time of the mixing section of the existing water purification plant is usually 30s, a folded paddle type stirrer is adopted for mechanical stirring equipment, and the rotating speed of the stirring equipment is 100-200 r/min; the outer diameter of the stirrer blade is 500-1500 mm.

According to the high-speed coagulation reactor for water supply treatment, the high-gradient rapid mixing after dosing in the mixing reactor is realized by reducing the outer diameter of the stirrer blade to 200-400 mm, increasing the rotating speed of the stirrer to 800-1200 r/min and shortening the distance between a dosing outlet and the blade to 10-30 mm, the stirring intensity is reasonably adjusted, and the water flow structure required for collision and aggregation of initial particles is ensured to be formed in a short time. The time of the mixing reaction is shortened to 5-10 s, the reaction of the mixing section is controlled within the most effective time, the subsequent invalid mixing reaction of 20s is avoided, and the coagulant and the colloid particles are uniformly mixed within the shortest time, so that the destabilizing effect of the subsequent colloid particles is improved. Meanwhile, the mixing time is shortened, so that the volume of the mixing pool is reduced, and the engineering construction investment is reduced.

2. Forming micro-vortex diffusion

In the mixing reaction process, blade energy rotated by the stirrer is transferred to the water body, so that the liquid in the reactor generates local shearing flow, large and small vortex groups with different dimensions are generated, and rapid and turbulent convection movement of the water body in a local range is formed. Such convective diffusion in a local region caused by the swirling motion is called vortex diffusion. The vortex diffusion rate depends on the turbulence state of the body of water being stirred. The higher the turbulence, the faster the mixing rate.

According to the high-speed coagulation reactor for water supply treatment, the mesh turbulence barrel is arranged on the periphery of the high-speed stirrer, when the blades of the turbine stirrer rotate, fluid flows outwards through meshes of the turbulence barrel, a high-turbulence full mixing area is formed between the stirrer and the turbulence barrel, a high-speed jet flow is generated at the outflow position of the meshes, so that the fluid has a higher pressure head, liquid is pushed to circulate in the reactor, micro-vortex diffusion is further formed, the turbulence degree of a flow field in the reactor is increased, mixing on the microscopic scale of materials is promoted, and the stirring effect is improved. Under the flow guiding effect of the turbulent flow cylinder, water flows into the cylinder from the top and the bottom of the cylinder to form a circulation, high-speed radial flow and axial flow are generated, tangential flow is reduced, the problems of uneven flow field and easy generation of swirling phenomenon of the original stirrer are solved, and the mixing is faster and more uniform.

Claims

1. A high-speed coagulation reactor for water treatment is characterized in that: the reactor comprises a reactor tank body (1), a water inlet pipe (6) and a water outlet pipe (7), wherein an L-shaped feed pipe (8) is arranged at the top of the reactor tank body (1), a stirrer (4) and a turbulence barrel (5) are also arranged in the reactor tank body (1), and the stirrer (4) is arranged in the center of the reactor tank body (1) and is connected to a motor (2) through a speed reducer (3); the turbulent flow cylinder (5) is fixed at the top end of the reactor tank body (1) and is arranged between the stirrer (4) and the reactor tank body (1); the water inlet pipe (6) and the water outlet pipe (7) are respectively embedded on the outer walls of the left side and the right side of the reactor tank body (1);

the L-shaped feeding pipe (8) is positioned in the turbulent flow cylinder (5), and a discharge hole of the L-shaped feeding pipe is positioned at a position 10-30 mm below the stirrer (4);

the water inlet pipe (6) is positioned at the bottom of the reactor tank body (1), and the water outlet pipe (7) is positioned at the upper part of the reactor tank body (1);

the diameter of the turbulence tube (5) is 2-3 times of the outer diameter of a blade of the stirrer (4), holes are uniformly distributed on the tube body of the turbulence tube (5), and the aperture ratio is not less than 50%;

the outer diameter of the blade of the stirrer (4) is 200-400 mm, the angle of the blade is 5-20 degrees, and the rotating speed of the stirrer (4) is 800-1200 r/min.