CN216273612U

CN216273612U - Sewage treatment system

Info

Publication number: CN216273612U
Application number: CN202122385202.0U
Authority: CN
Inventors: 张子涛
Original assignee: Shuifa Zhonglv Beijing Engineering Technology Co ltd
Current assignee: Shuifa Zhonglv Beijing Engineering Technology Co ltd
Priority date: 2021-09-29
Filing date: 2021-09-29
Publication date: 2022-04-12
Anticipated expiration: 2031-09-29

Abstract

The utility model discloses a sewage treatment system, which comprises a sewage pretreatment device, a primary sedimentation tank, an HPB biochemical tank, a secondary sedimentation tank, a secondary lift pump set, a magnetic coagulation sedimentation tank, an ozone contact tank, an active sand filter tank and a contact disinfection tank, wherein the sewage pretreatment device, the primary sedimentation tank, the HPB biochemical tank, the secondary sedimentation tank, the secondary lift pump set, the magnetic coagulation sedimentation tank, the ozone contact tank, the active sand filter tank and the contact disinfection tank are sequentially connected in the sewage flowing direction, the sewage treated by the HPB biochemical tank is sequentially divided into an anaerobic zone, an anoxic zone and an aerobic zone in the sewage flowing direction, and the HPB biochemical tank is connected with a composite powder carrier dosing device for dosing composite powder carriers to the anaerobic zone, the anoxic zone and the aerobic zone. The sewage treatment system improves the purification rate of sewage, ensures that the treated sewage reaches the standard of surface water environmental quality standard (GB3838-2002) standard IV water quality, and has the advantages of high treatment efficiency, good effluent quality, strong impact load resistance, safer and more stable operation and the like.

Description

Sewage treatment system

Technical Field

The utility model belongs to the technical field of sewage treatment, and particularly relates to a sewage treatment system.

Background

The sewage treatment device adopted by the existing sewage treatment plant comprises a pretreatment device, a dust outlet tank, an AAO biochemical tank, a secondary sedimentation tank, an active sand filter tank and a disinfection tank which are connected in sequence, inlet water is pretreated, primarily precipitated, AAO biochemical, secondarily precipitated, activated sand filtered and subjected to contact disinfection and then is discharged up to the standard, the water quality of outlet water can reach the first-class A standard of pollutant discharge standard of urban sewage treatment plant (GB18918-2002), but the water quality of outlet water is improved from the first-class A standard of pollutant discharge standard of urban sewage treatment plant (GB18918-2002) to the standard of quasi-IV-class water quality standard of surface water environment quality standard (GB3838-2002) with higher and higher environmental requirements. The effluent treated by the existing sewage treatment device can not reach the water quality standard.

Accordingly, further developments and improvements are still needed in the art.

SUMMERY OF THE UTILITY MODEL

In order to solve the above problems, a sewage treatment system is proposed, and the following technical solutions are provided:

a sewage treatment system comprises a sewage pretreatment device, a primary sedimentation tank, an HPB biochemical tank, a secondary sedimentation tank, a secondary lifting pump set, a magnetic coagulation sedimentation tank, an ozone contact tank, an active sand filter tank and a contact disinfection tank, wherein the sewage pretreatment device, the primary sedimentation tank, the HPB biochemical tank, the secondary sedimentation tank, the secondary lifting pump set, the magnetic coagulation sedimentation tank, the ozone contact tank, the active sand filter tank and the contact disinfection tank are sequentially connected in the sewage flowing direction, the secondary sedimentation tank is used for performing secondary solid-liquid separation on sewage treated by the HPB biochemical tank, the HPB biochemical tank is sequentially divided into an anaerobic zone, an anoxic zone and an aerobic zone in the sewage flowing direction, and composite powder carrier dosing equipment used for dosing composite powder carriers to the anaerobic zone, the anoxic zone and the aerobic zone is connected to the HPB biochemical tank.

And the sludge outlet of the secondary sedimentation tank is respectively communicated with the composite powder carrier cyclone separation and recovery device and the anaerobic zone of the HPB biochemical tank through the sludge reflux pump set.

Further, sewage pretreatment device includes that what connect gradually along sewage flow direction is used for holding back the thick grid of a large amount of suspended solids that waft in the sewage, the pump package of intaking, be arranged in removing the tiny suspended solids in the sewage in order to reduce the fine grid of biological treatment load, be arranged in the great inorganic sand grain's of separation proportion whirl grit chamber in the sewage, be provided with between whirl grit chamber and the HPB biochemical pond and be used for directly carrying the first pipe that surpasss in the HPB biochemical pond with sewage in the whirl grit chamber.

Furthermore, a second overrunning pipe and a third overrunning pipe are respectively arranged between the secondary lifting pump unit and the ozone contact tank as well as between the secondary lifting pump unit and the active sand filter tank, and a fourth overrunning pipe is arranged between the magnetic coagulation sedimentation tank and the active sand filter tank.

Further, the device also comprises a sludge treatment device, and a sludge outlet of the primary sedimentation tank and a sludge outlet of the magnetic coagulation sedimentation tank are respectively communicated with an inlet of the sludge treatment device.

Further, the sludge treatment device comprises a sludge homogenizing tank and a sludge dewatering device which are sequentially connected along the sludge treatment direction, and a sludge outlet of the sludge homogenizing tank is communicated with an inlet of the sludge dewatering device.

Furthermore, the top overflow ports of the sludge homogenizing pool and the sludge dewatering device are communicated with the water inlet of the sewage pretreatment device.

Furthermore, all be provided with agitating unit in anaerobic zone, anoxic zone and the aerobic zone, agitating unit includes agitator motor, speed reducer and the stirring rake that top-down connects gradually, and the stirring rake comprises the (mixing) shaft and a plurality of hollow blade of connecting on the (mixing) shaft.

Further, a backwashing water outlet of the active sand filter is communicated with a water inlet of the sewage pretreatment device.

Further, a water outlet of the secondary lifting pump set is communicated with a water inlet of the sewage pretreatment device.

In summary, compared with the prior art, the utility model has the following beneficial effects:

(1) the quality of the effluent is stable: by adopting the HPB technology, the sludge concentration (6000-10000 mg/L) of the biochemical tank can be effectively improved, the impact resistance of a biochemical system is improved, and the water outlet effect of the biochemical tank is ensured; meanwhile, the HPB technology is adopted, the effluent quality can be flexibly controlled by adjusting process parameters, and the main water quality index is ensured to stably reach the standard of quasi-IV water quality.

(2) The operation cost is lower: according to the existing condition that the C/N of the influent water quality is seriously low, the composite carrier is adopted, the utilization effect of a carbon source can be effectively improved, the dosage of the carbon source is reduced, the TN of the effluent of a biochemical section can be stabilized below 15mg/L, denitrification is not required to be considered in subsequent advanced treatment, and the total operation cost is reduced by about 15 percent compared with the conventional process.

(3) The impact load resistance is stronger: the double-sludge process has the characteristics of both an activated sludge process and a biofilm process, has stronger impact load resistance of the system, can adapt to the fluctuation of water quantity and water quality in a larger range, and ensures stable water outlet.

(4) Reserving capacity expansion capacity in a long period: the composite powder carrier is added, so that a good attachment growth condition is provided for activated sludge microorganisms, the sludge concentration of a biochemical pool is increased to 2-3 times of the original concentration, and the microbial biomass and the biological population number in a unit volume are greatly increased, so that the treatment efficiency of the traditional activated sludge method can be increased by more than 1 time, sufficient redundancy of the system is ensured, and reservation can be made for later-stage increment and capacity expansion.

Drawings

FIG. 1 is a schematic view showing the structure of a sewage treatment system according to embodiment 1 of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following description is given for clear and complete description of the technical solution of the present invention with reference to the embodiments of the present invention, and other similar embodiments obtained by those skilled in the art without creative efforts based on the embodiments of the present application shall fall within the protection scope of the present application. In addition, directional terms such as "upper", "lower", "left", "right", etc. in the following embodiments are directions with reference to the drawings only, and thus, the directional terms are used for illustrating the present invention and not for limiting the present invention.

Detailed description of the preferred embodiment 1

As shown in fig. 1, a sewage treatment system includes a sewage pretreatment device, a primary sedimentation tank 150 for performing primary solid-liquid separation on pretreated sewage, an HPB biochemical tank for performing biochemical treatment on sewage, a secondary sedimentation tank 170 for performing secondary solid-liquid separation on sewage treated by the HPB biochemical tank, a secondary lift pump set 180, a magnetic coagulation sedimentation tank 190, an ozone contact tank 210, an active sand filter 220, and a contact disinfection tank 230, which are sequentially connected in a sewage flow direction, the HPB biochemical tank is sequentially divided into an anaerobic zone 161, an anoxic zone 162, and an aerobic zone 163 in the sewage flow direction, and a composite powder carrier dosing device 260 for dosing composite powder carriers to the anaerobic zone 161, the anoxic zone 162, and the aerobic zone 163 is connected to the HPB biochemical tank. The sewage enters an HPB biochemical tank after being pretreated, a proper amount of composite powder carriers are required to be gradually introduced to be mixed with the activated sludge in the tank, the concentration of mixed liquid in the tank is improved, more carriers for growth of attached microorganisms are provided, the biological diversity in the activated sludge is increased, and the pollutants in the water are efficiently removed. And a composite powder carrier dosing device 260 is adopted to dose composite powder carriers into the anaerobic zone 161, the anoxic zone 162 and the aerobic zone 163, and the composite powder carriers are dosed into the HPB biochemical tank, so that a microbial system with symbiosis of suspended growth and attached growth of double mud is constructed while the concentration of mixed liquid in the biological tank is improved. Specifically, the composite powder carrier dosing device 260 is a doser.

The composite powder carrier means that powder carrier particles are compounded with particles of the alternative carbon source. According to the molar ratio of the electron donor needed by the reduction of the nitrate nitrogen, the mass of the particles of the alternative carbon source accounts for about 1 percent or more of the mass of the particles of the powder carrier. The method for preparing the composite powder carrier can adopt a dry method or a wet method, wherein the dry method is generally used for compounding the organic alternative carbon source, and the wet method is generally used for compounding the inorganic alternative carbon source. The composite mechanism mainly utilizes the mass difference and the surface energy of the powder carrier particles and the alternative carbon source particles, and the alternative carbon source particles can be adsorbed when the alternative carbon source particles can overcome the repulsion energy peak and are close to the surfaces of the powder carrier particles. Most of the attached microorganisms in the sewage biological treatment process are nitrifying bacteria, denitrifying bacteria, facultative bacteria, other functional bacteria and the like, and the bacteria grow into dominant bacteria and need attached carriers for growth, longer sludge age and electron donors of carbon sources or alternative carbon sources for promoting the denitrification process. After the composite powder carrier is put into the HPB biochemical pool, a growth platform and an alternative carbon source are mainly provided for the attached microorganisms. Due to the fact that a large number of composite powder carriers are added (VSS/SS is 0.3-0.4), a microbial system with symbiosis of 'double mud' in suspension growth and attachment growth is constructed in the biochemical pool, and biological diversity and microbial abundance of the system are improved.

Further, the sewage treatment system also comprises a composite powder carrier cyclone separation and recovery device 240 for recovering the powder carriers, a sludge outlet of the secondary sedimentation tank 170 is connected with a sludge reflux pump set 250, and a sludge outlet of the secondary sedimentation tank 170 is respectively communicated with the composite powder carrier cyclone separation and recovery device 240 and the HPB biochemical tank anaerobic zone 161 through the sludge reflux pump set 250. The concentration and separation of the secondary sedimentation tank 170 and the recovery and circulation of the composite powder carrier in the discharged excess sludge realize the double sludge age and synchronously improve the biological nitrogen and phosphorus removal efficiency. The microbial population structure of the biochemical system can be regulated and optimized by the composite powder carrier cyclone separation and recovery device 240. The double sludge ages can be synchronously realized by utilizing the composite powder carrier cyclone separation and recovery device 240. The microorganisms attached to the composite powder carrier are continuously circulated to realize the sludge growth, which is beneficial to strengthening the biological denitrification of the system; and the suspended active sludge (short sludge age microorganisms) is discharged according to the requirement of phosphorus removal every time, so that the biological phosphorus removal of the system can be enhanced. The composite powder carrier can be recycled through the composite powder carrier cyclone separation and recovery device 240, and the operation cost is saved.

Further, the sewage pretreatment device comprises a coarse grating 110, a water inlet pump set 120, a fine grating 130 and a cyclone grit chamber 140, wherein the coarse grating 110, the water inlet pump set 120, the fine grating 130 and the cyclone grit chamber 140 are sequentially connected along the flowing direction of the sewage and are used for intercepting a large amount of floating suspended matters in the sewage so as to reduce the biological treatment load, the cyclone grit chamber 140 is used for separating inorganic sand grains with large specific gravity in the sewage, and a first surpassing pipe 270 is arranged between the cyclone grit chamber 140 and the HPB biochemical tank and is used for directly conveying the sewage in the cyclone grit chamber 140 into the HPB biochemical tank.

Specifically, the sewage pretreatment device adopts a physical and chemical treatment method, and mainly removes solid pollutants in a suspended state in the sewage. The coarse grating 110 is of a rotary type, and the coarse grating 110 is used for intercepting large floating objects and protecting the water inlet pump unit 120. The fine grid 130 further removes fine suspended matters in the sewage, reducing the biological treatment load. The cyclone grit chamber 140 has a simple structure and occupies less land, and has the function of separating inorganic sand grains with higher specific gravity in sewage to avoid abrasion to subsequent sewage treatment equipment. The effluent of the fine grid 130 automatically flows into a cyclone grit chamber 140 to remove inorganic sand with larger particle size in the sewage and then enters a primary settling tank 150, and the wastewater can be subjected to primary solid-liquid separation in the primary settling tank 150.

Further, a second overrunning pipe 280 and a third overrunning pipe 290 are respectively arranged between the secondary lifting pump group 180 and the ozone contact tank 210 and between the secondary lifting pump group 180 and the active sand filter tank 220, and a fourth overrunning pipe 310 is arranged between the magnetic coagulation sedimentation tank 190 and the active sand filter tank 220. The magnetic coagulation sedimentation tank 190, the ozone contact tank 210 and the sand filter tank can be surpassed, and when the water inlet quality is better, the magnetic coagulation sedimentation tank 190, the ozone contact tank 210 and the sand filter tank can be surpassed according to the water quality condition.

Further, the sewage treatment system further comprises a sludge treatment device, and a sludge outlet of the primary sedimentation tank 150 and a sludge outlet of the magnetic coagulation sedimentation tank 190 are respectively communicated with an inlet of the sludge treatment device.

Further, the sludge treatment device comprises a sludge homogenizing tank 320 and a sludge dewatering device 330 which are sequentially connected along the sludge treatment direction, and a sludge outlet of the sludge homogenizing tank 320 is communicated with an inlet of the sludge dewatering device 330.

Further, the top overflow ports of the sludge homogenizing tank 320 and the sludge dewatering device 330 are both communicated with the water inlet of the sewage pretreatment device.

Furthermore, stirring devices are arranged in the anaerobic zone 161, the anoxic zone 162 and the aerobic zone 163 and comprise a stirring motor, a speed reducer and a stirring paddle which are sequentially connected from top to bottom, the stirring paddle consists of a stirring shaft and a plurality of hollow blades connected to the stirring shaft, the biological reaction efficiency of the HPB biochemical pool is ensured, the deposition of composite powder carriers is prevented from being initially added, the convective mass transfer is enhanced, the utilization rate of dissolved oxygen is improved, and the stirring motor, the speed reducer and the stirring paddle are vertically mounted in a suspension manner from top to bottom.

Further, a backwashing water outlet of the activated sand filter 220 is communicated with a water inlet of the sewage pretreatment device. The active sand filter 220 has the advantages of high efficiency, low operating cost, simple and convenient maintenance, good filtering effect, stable effluent quality and the like.

Further, the water outlet of the secondary lift pump unit 180 is communicated with the water inlet of the sewage pretreatment device.

The sewage treatment system selects an ozone oxidation method to remove organic matters which are difficult to degrade by biological oxidation. The ozone catalytic oxidation technology is an efficient advanced sewage treatment technology and is a research hotspot in the field of sewage treatment in recent years. The main mechanism is that ozone forms hydroxyl free radicals under the action of a catalyst, the hydroxyl free radicals have extremely high oxidation potential (2.80EV) and extremely strong oxidation capability, can perform rapid chain reaction with most organic matters, and can oxidize harmful substances into CO2, H2O or mineral salts without selectivity and secondary pollution. The ozone oxidation method has strong capabilities of decoloring and removing organic pollutants, but has high operation cost, selectivity on the oxidation of organic matters, can not completely mineralize the pollutants in low dosage and short time, and the intermediate products generated by decomposition can prevent the oxidation process of ozone.

The working principle of the sewage treatment system is as follows: the sewage is collected by a sewage pipe network and is conveyed to a pretreatment device of a sewage treatment plant, the sewage pretreatment device comprises a coarse grating 110, a fine grating 130, a rotational flow grit chamber 140 and a primary settling chamber 150, and various suspended matters in the sewage are mainly removed. The sewage firstly enters the coarse grating 110, larger floating objects in the sewage are cut off, and the normal operation of subsequent mechanical equipment such as a water pump and the like is protected. The water from the coarse screen 110 is pumped to the fine screen 130 by the sewage pump to remove the smaller floating materials in the sewage. The gate slag cut off by the coarse gate 110 and the fine gate 130 is conveyed to a screw press by a conveyor to be dehydrated and then incinerated. The effluent of the fine grid 130 automatically flows into a rotational flow grit chamber 140 to remove inorganic sand with larger particle size in the sewage and then enters a primary sedimentation tank 150. The sewage automatically flows into an HPB biochemical tank after primary solid-liquid separation is carried out in a primary sedimentation tank 150, the HPB biochemical tank is sequentially divided into an anaerobic zone 161, an anoxic zone 162 and an aerobic zone 1633, and by adopting an HPB process and adding a composite powder carrier into the HPB biochemical tank, a microorganism system with symbiosis of suspended growth and attached growth of 'double mud' is constructed while the concentration of mixed liquor in the biological tank is improved; and the concentration and separation of the secondary sedimentation tank 170 and the recovery and circulation of the composite powder carrier in the discharged excess sludge are carried out, thereby realizing double sludge age, synchronously improving the biological nitrogen and phosphorus removal efficiency, and carrying out solid-liquid separation in the secondary sedimentation tank 170. The effluent treated by the secondary sedimentation tank 170 is subjected to magnetic coagulation sedimentation, ozone contact oxidation and active sand filtration, is subjected to contact disinfection by sodium hypochlorite in the contact disinfection tank 230, and is discharged through a drainage pipeline to reach the standard.

Sludge treatment process: the sludge in the magnetic coagulation sedimentation tank 190 and the residual sludge in the primary sedimentation tank 150 and the secondary sedimentation tank 170 are discharged into a sludge homogenizing tank 320, the sludge in the sludge homogenizing tank 320 is conveyed to a sludge dewatering device 330 through a sludge feeding pump, the moisture content of the dewatered sludge can reach below 80%, and the dewatered sludge is conveyed to a sludge piling shed through a conveyor to be collected and then disposed.

The present invention has been described in detail, and it should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the utility model, are intended for purposes of illustration only and are not intended to limit the scope of the utility model.

Claims

1. A sewage treatment system is characterized in that: the device comprises a sewage pretreatment device, a primary sedimentation tank, an HPB biochemical tank, a secondary sedimentation tank, a secondary lift pump set, a magnetic coagulation sedimentation tank, an ozone contact tank, an active sand filter tank and a contact disinfection tank, wherein the sewage pretreatment device is sequentially connected along the sewage flow direction, the primary sedimentation tank is used for performing primary solid-liquid separation on pretreated sewage, the HPB biochemical tank is used for performing biochemical treatment on the sewage, the secondary sedimentation tank is used for performing secondary solid-liquid separation on the sewage treated by the HPB biochemical tank, the HPB biochemical tank is sequentially divided into an anaerobic zone, an anoxic zone and an aerobic zone along the sewage flow direction, and the HPB biochemical tank is connected with composite powder carrier dosing equipment for dosing composite powder carriers into the anaerobic zone, the anoxic zone and the aerobic zone.

2. The wastewater treatment system according to claim 1, wherein: the device also comprises a composite powder carrier cyclone separation and recovery device for recovering the powder carrier, a sludge outlet of the secondary sedimentation tank is connected with a sludge reflux pump set, and the sludge outlet of the secondary sedimentation tank is respectively communicated with the composite powder carrier cyclone separation and recovery device and the anaerobic zone of the HPB biochemical tank through the sludge reflux pump set.

3. The wastewater treatment system according to claim 1, wherein: the sewage pretreatment device comprises a coarse grating, a water inlet pump set, a fine grating and a cyclone grit chamber, wherein the coarse grating is used for intercepting a large amount of floating suspended matters in sewage, the water inlet pump set is used for removing fine suspended matters in the sewage so as to reduce biological treatment load, the cyclone grit chamber is used for separating inorganic sand grains with large specific gravity in the sewage, and a first overrunning pipe is arranged between the cyclone grit chamber and the HPB biochemical chamber and used for directly conveying the sewage in the cyclone grit chamber into the HPB biochemical chamber.

4. The wastewater treatment system according to claim 1, wherein: and a second overrunning pipe and a third overrunning pipe are respectively arranged between the secondary lifting pump group and the ozone contact tank as well as between the secondary lifting pump group and the active sand filter tank, and a fourth overrunning pipe is arranged between the magnetic coagulation sedimentation tank and the active sand filter tank.

5. The wastewater treatment system according to claim 1, wherein: the device also comprises a sludge treatment device, and a sludge outlet of the primary sedimentation tank and a sludge outlet of the magnetic coagulation sedimentation tank are respectively communicated with an inlet of the sludge treatment device.

6. The wastewater treatment system according to claim 5, wherein: the sludge treatment device comprises a sludge homogenizing tank and a sludge dewatering device which are sequentially connected along the sludge treatment direction, and a sludge outlet of the sludge homogenizing tank is communicated with an inlet of the sludge dewatering device.

7. The wastewater treatment system according to claim 6, wherein: and the top overflow ports of the sludge homogenizing tank and the sludge dewatering device are communicated with a water inlet of the sewage pretreatment device.

8. The wastewater treatment system according to claim 1, wherein: all be provided with agitating unit in anaerobic zone, anoxic zone and the aerobic zone, agitating unit includes agitator motor, speed reducer and the stirring rake that top-down connects gradually, and the stirring rake comprises (mixing) shaft and a plurality of hollow blade of connecting on the (mixing) shaft.

9. The wastewater treatment system according to claim 1, wherein: and a backwashing water outlet of the active sand filter is communicated with a water inlet of the sewage pretreatment device.

10. The wastewater treatment system according to claim 1, wherein: and the water outlet of the secondary lifting pump set is communicated with the water inlet of the sewage pretreatment device.