CN105753271A - Biological filter-biological contact oxidation-steel slag absorption sewage treatment system and method for sewage treatment by utilizing system - Google Patents

Abstract

The invention provides a biofilter?biological contact oxidation?steel slag adsorption sewage treatment system and its method for sewage treatment. The system includes a biofilter, a biological contact oxidation pond, a hydraulic circulation pump, an aeration pipe, The pump and the sedimentation tank also include an adsorption phosphorus removal tank with a steel slag packing layer inside, the biological filter is provided with a water inlet, and the water outlet of the biological filter is connected with the biological contact oxidation tank, and the biological contact oxidation The pool includes an aerobic zone and an anaerobic zone, the hydraulic circulation pump is connected to the aerobic zone and the anaerobic zone, the aeration tube is arranged at the bottom of the aerobic zone, and the aeration pump is connected to the aeration zone The pipes are connected to realize aeration, the biological contact oxidation tank is connected with the water inlet of the sedimentation tank, the water outlet of the sedimentation tank is connected with the water inlet of the adsorption phosphorus removal tank, and the adsorption phosphorus removal tank is set There is a water outlet. The method uses the above-mentioned system to treat the sewage, so as to realize the effects of organic matter removal, nitrogen and phosphorus removal.

Description

A biofilter-biological contact oxidation-steel slag adsorption sewage treatment system and its method for sewage treatment

technical field

The invention belongs to the field of water environment protection research and application, and in particular relates to a biofilter-biological contact oxidation-steel slag adsorption sewage treatment system and a method for sewage treatment thereof.

Background technique

With the acceleration of my country's urbanization process and the rapid development of township enterprises, the discharge of urban sewage is also increasing. However, due to the old concept of "emphasizing construction and ignoring environmental protection" in the past, urban infrastructure construction lags far behind urban construction, lacking necessary sewage collection systems and sewage treatment facilities. The disorderly and turbulent flow of sewage not only directly pollutes the ecological environment of small towns, but also causes serious pollution of rivers and lakes, and has become an important source of pollution for the regional water environment.

At present, the applicable technology for urban sewage treatment in my country is still immature, and some relatively developed urban sewage treatment plants continue to use the technology of large and medium-sized urban sewage treatment plants. However, for small towns with backward development, it is difficult to practice these treatment processes in small towns due to problems such as large infrastructure costs, large investment in equipment, lack of experienced personnel in operation and management, and complex technological processes.

Therefore, in view of the characteristics of small town sewage discharge, wide dispersion, large changes in water quality and quantity, high difficulty in collection, high content of nitrogen, phosphorus and suspended solids, and basically free of heavy metal ions and other toxic and harmful substances, at the same time taking into account the objective economic technology In terms of personnel and management personnel, some small and medium-sized sewage integrated treatment equipment with their own characteristics have emerged as the times require, which have a good treatment effect on domestic sewage in small towns.

The existing small town sewage integration device combines multiple processes in the structure and combines them in the same equipment to treat sewage, which has the advantages of short construction period, less investment, less land occupation, good treatment effect and low energy consumption. , easy management and other advantages, mainly include: A/0 integrated device, SBR sequencing batch reactor, integrated membrane bioreactor, etc. However, most of the processes of these integrated devices still combine traditional treatment methods, and there are many process units, insufficiently compact structures, and many ancillary equipment; and most integrated devices mainly treat organic matter in sewage, while ignoring Phosphorus and nitrogen removal, facing the increasingly serious problem of water eutrophication, these devices are difficult to meet the treatment requirements.

Contents of the invention

Aiming at the above-mentioned deficiencies existing in the prior art, the technical problem to be solved by the present invention is: for the existing integrated sewage treatment device in small cities and towns, the organic matter in the sewage is mainly used as the processing object, and the deficiencies of phosphorus and nitrogen removal in the sewage are ignored, and the Provided is a biofilter-biological contact oxidation-steel slag adsorption sewage treatment system capable of simultaneously realizing the simultaneous treatment effects of organic matter removal, biological nitrification and denitrification, biological phosphorus removal and adsorption phosphorus removal, and a method for treating sewage.

To achieve the above object, the present invention adopts the following technical scheme: a biofilter-biological contact oxidation-steel slag adsorption sewage treatment system, including a biofilter, a biological contact oxidation tank, a hydraulic circulation pump, an aeration pipe, an aeration pump and a sedimentation The pool also includes an adsorption dephosphorization pool with a steel slag packing layer inside; the biofilter is provided with a water inlet, and the water outlet of the biofilter communicates with the biological contact oxidation pool, and the biological contact oxidation pool includes a good anaerobic zone and anaerobic zone, the hydraulic circulation pump communicates with the aerobic zone and anaerobic zone, the aeration tube is arranged at the bottom of the aerobic zone, and the aeration pump is connected with the aeration tube for To realize aeration, the biological contact oxidation tank is connected with the water inlet of the sedimentation tank, the water outlet of the sedimentation tank is connected with the water inlet of the adsorption phosphorus removal tank, and the adsorption phosphorus removal tank is provided with a water outlet .

When the sewage treatment system of the present invention is in use, the sewage enters the biofilter, and after removing part of the organic matter in the sewage under the degradation of microorganisms on the suspended filler in the biofilter, it is pumped into the biological contact oxidation tank, and is carried out under the circulation of the hydraulic circulation pump. Alternate anaerobic-aerobic reaction, through the action of aerobic bacteria and anaerobic bacteria to remove organic matter, nitrogen and phosphorus in sewage, introduce the effluent from the biological contact oxidation tank into the sedimentation tank to achieve mud-water separation, and clean water after mud-water separation Introduced into the adsorption phosphorus removal tank, under the action of steel slag filler, the phosphorus in the sewage is deeply removed, so that the phosphorus in the sewage can be effectively removed, and the treated water is discharged through the outlet pipe to complete the sewage treatment process.

Further, a perforated water distribution pipe is arranged above the biological filter, and the perforated water distribution pipe communicates with the water inlet of the biological filter. In this way, the sewage to be treated can be evenly distributed on the surface of the biofilter, has a larger contact area with the suspended filler in the biofilter, and can be better degraded by microorganisms to remove organic matter.

As an optimization, the biological filter is arranged above the biological contact oxidation tank. In this way, the water can be directly introduced into the biological contact oxidation tank through the gravity of the effluent without using a water pump, and the biological filter is placed on the top, which saves the floor space of the whole set of equipment and is more suitable for in-situ collection and treatment of sewage.

As another optimization, the biological contact oxidation tank is an overall central island-like annular oxidation ditch structure, and the central island is provided with the sedimentation tank and the adsorption phosphorus removal tank. In this way, the contact oxidation tank, the sedimentation tank, and the adsorption phosphorus removal tank can be collected in one treatment tank, which saves the floor space, and the use of such a central island structure can form an aerobic-anaerobic system around the central island. The flow can promote the continuous circulation of sewage for anaerobic-aerobic reaction.

Further, multiple rows of steel slag packing layers are sequentially arranged along the direction from the water inlet to the water outlet of the adsorption dephosphorization tank. In this way, multiple rows of steel slag packing layers are arranged along the water flow direction, which can reduce the bulk density of steel slag, make the contact area between sewage and steel slag larger, effectively improve the phosphorus removal efficiency, and make the phosphorus removal effect better.

As an optimization, the steel slag filled in the adsorption dephosphorization tank is the modified steel slag obtained after soaking in alkali solution for 24 hours and drying at 700°C for 1 hour. The modified steel slag treated in this way is loose and porous, has a large specific surface area, and has a better adsorption and removal effect on phosphorus in sewage.

The method for sewage treatment using the above biofilter-biological contact oxidation-steel slag adsorption sewage treatment system comprises the following steps:

1) Introduce the sewage into the scum removal device to remove the suspended impurities in the sewage;

2) Transfer the sewage treated in step 1) into the regulating tank for regulation and storage;

3) Pump the effluent from step 2) into the biofilter, and remove some organic matter in the water through the degradation of microorganisms on the suspended filler in the biofilter;

4) The effluent treated in step 3) is introduced into the biological contact oxidation tank, and the alternating anaerobic-aerobic reaction is carried out under the action of the hydraulic circulation pump, and the denitrification of nitrogen is completed under the action of anaerobic bacteria in the anaerobic zone reaction and anaerobic phosphorus release reaction, under the action of aerobic bacteria in the aerobic zone, nitrogen nitrification reaction, aerobic excess phosphorus uptake reaction and organic matter degradation reaction are completed, and organic matter, nitrogen and phosphorus in sewage are removed;

5) Introduce the effluent treated in step 4) into the sedimentation tank to realize the separation of mud and water;

6) The effluent treated in step 5) is introduced into the adsorption phosphorus removal tank, and the phosphorus in the sewage is subjected to deep adsorption treatment by using steel slag filler.

The sewage is treated in this way: firstly, the large suspended solids contained in the sewage are removed through the scum removal device, so as to prevent the suspended solids from clogging the pores between the water pipes and fillers in the subsequent treatment; then the sewage after the suspended solids are removed is introduced into the regulating tank After adjusting the inflow and water quality, it is passed into the biofilter, and the organic matter and nitrogen in the sewage are removed by the function of the biofilter and the biological contact oxidation pond, and a small part of phosphorus is removed; the sewage after contact oxidation is further passed into the The sludge in the sewage is removed in the sedimentation tank to realize the separation of mud and water; finally, the sewage is passed into the adsorption phosphorus removal tank, and the phosphorus element in the sewage is deeply removed by the adsorption of steel slag, and most of the phosphorus element in the sewage is removed . This method is used to realize the simultaneous removal of organic matter, biological nitrification and denitrification denitrification treatment, biological phosphorus removal and adsorption phosphorus removal, so that the treated sewage can meet the first-level A discharge standard of "Pollutant Discharge Standards for Urban Sewage Treatment Plants".

Further, the hydraulic retention time of the biofilter in step 3) is 2 to 6 hours. In this way, the organic matter in the sewage can be degraded more thoroughly under the action of microorganisms in the biofilter, and a better sewage treatment effect can be achieved.

Further, step 4) The hydraulic retention time of the biological contact oxidation tank is 10-24 hours, the operating air-water ratio is 9-15, and the hydraulic load is 0.075-0.175m³/(m ² ·h). The use of such conditions in the biological contact oxidation tank can make the impurities in the sewage undergo a sufficient aerobic-anaerobic cycle reaction, which is more conducive to the completion of nitrogen denitrification reaction and anaerobic phosphorus release reaction in the anaerobic zone. Under the action of aerobic bacteria in the oxygen zone, nitrogen nitrification and aerobic overabsorption of phosphorus were completed.

As an optimization, in step 6) in the adsorption dephosphorization tank, 1-5 g of steel slag is used to fill the steel slag filler layer for every 100 mL of wastewater treated. With such a usage amount of steel slag, the phosphorus element in the sewage can be more fully adsorbed, so that the content of phosphorus element in the effluent is lower, and there is no need for subsequent complicated phosphorus removal process.

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

1. The present invention combines microbial degradation, precipitation separation, and steel slag adsorption in a circular island rectangular reactor, so that the removal of organic matter, biological nitrification and denitrification, biological phosphorus removal and adsorption phosphorus removal can be carried out simultaneously, giving full play to their respective advantages and realizing Distributed sewage collection and treatment in small towns, so that the quality of the treated effluent meets the "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB 18918-2002) Tier A emission standard.

2. The sewage treatment system of the present invention can adopt an integrated module design, which can flexibly respond to the treatment requirements of different treatment scales and topographical conditions, with convenient operation and management, low capital investment and operating equipment costs, and a wide range of process applications.

3. The fillers of the biofilter and the biological contact oxidation tank in the sewage treatment system of the present invention are respectively suspended fillers and three-dimensional elastic fillers, which have the advantages of easy film formation, high biological activity, large specific surface area, and not easy to be blocked, so the reactor is resistant to clogging. Strong impact load capacity, good sewage treatment effect, suitable for urban sewage treatment with large daily variation coefficient of water quality and quantity.

4. The sewage treatment system of the present invention has less sludge output, no fear of sludge bulking, and no need to set up sludge backflow, which reduces the concerns of difficult sludge disposal in the later stage, and also reduces operating costs.

5. The present invention uses industrial waste steel slag as the dephosphorization adsorbent, taking advantage of its good adsorption performance and wide sources, compared with the prior art that only uses biological contact oxidation method for dephosphorization, it has achieved better dephosphorization effect , and steel slag as a wastewater treatment agent not only saves the cost of steel slag disposal, reduces environmental pollution, enables steel slag to be used as a resource, but also realizes sewage treatment, which can be said to kill two birds with one stone.

6. The sewage treatment method of the present invention does not require special pre-treatment or post-treatment steps for the sewage, and only the sewage is introduced into the sewage treatment system of the present invention, and the treatment conditions during the operation are controlled to achieve high-quality water treatment effects , the water treatment process is simpler and more convenient.

Description of drawings

Fig. 1 is the schematic plan view of sewage treatment system;

Figure 2 is a cross-sectional view of the sewage treatment system.

detailed description

The present invention will be described in further detail below in conjunction with specific embodiments and accompanying drawings. This implementation case is carried out on the premise of the technology of the present invention, and the detailed implementation and specific operation process are given to illustrate the inventiveness of the present invention, but the protection scope of the present invention is not limited to the following examples.

During specific implementation, as shown in Figures 1 to 2, a biofilter-biological contact oxidation-steel slag adsorption sewage treatment system includes a biofilter 1, a biological contact oxidation tank 2, a hydraulic circulation pump 3, and an aeration pipe 4 , aeration pump 5, sedimentation tank 6, also includes the adsorption dephosphorization tank 7 that the inside is provided with steel slag filler layer, the water inlet place of described biofilter 1 can be provided with water inlet pipe 8, and the water outlet of biofilter 1 passes through The pipeline communicates with the biological contact oxidation tank 2, the biological contact oxidation tank 2 is divided into an aerobic zone 9 and an anaerobic zone 10, and the hydraulic circulation pump 3 communicates with the aerobic zone 9 and anaerobic zone 10, The aeration pipe 4 is arranged at the bottom of the aerobic zone 9, the aeration pump 5 is connected to the aeration pipe 4 to realize aeration, and the biological contact oxidation tank 2 is connected to the sedimentation tank 6 through the pipeline. The water inlet is connected, and the water outlet of the sedimentation tank 6 is connected with the water inlet of the adsorption dephosphorization tank 7 , and the bottom of the adsorption dephosphorization tank 7 is provided with an outlet pipe 11 .

Considering that the sewage to be treated contains large suspended solids, and in order to allow the sewage to flow into the biofilter for sewage treatment without interruption, a scum removal device 12 (preferably a grid pool) and a regulating pool 13 can also be provided, so The water outlet of the scum removing device 12 is connected with the water inlet of the adjustment tank 13 , and the water outlet of the adjustment tank 13 is connected with the biological filter 1 through the water inlet pipe 8 .

In order to make the sewage to be treated evenly distributed on the surface of the biofilter 1, and have a larger contact area with the suspended filler in the biofilter 1, a perforated water distribution pipe 14 is set above the biofilter 1, and the perforated The water distribution pipe 14 communicates with the water inlet pipe 8 .

In order to make the contact area between the sewage and the steel slag larger in the adsorption dephosphorization tank, reduce the bulk density of the steel slag, and effectively improve the phosphorus removal efficiency, multiple rows of steel slag fillers are sequentially arranged along the direction from the water inlet to the water outlet of the adsorption dephosphorization tank 7 Layer 15 makes the phosphorus removal effect better.

In order to further remove phosphorus in sewage, the steel slag in the adsorption dephosphorization tank 7 can be modified steel slag obtained after soaking in alkaline solution for 24 h and drying at 700°C for 1 h. Such modified steel slag is loose Porous, large specific surface area, better adsorption and phosphorus removal effect.

In order to avoid the use of water pumps and save the floor area of the whole set of equipment, making it more suitable for the in-situ collection and treatment of sewage, the biological filter 1 is arranged above the biological contact oxidation tank 2, so that only the biological filter The gravity of the water out of the pool 1 can directly introduce the water into the biological contact oxidation pool 2, which saves energy and space.

In order to further save space and make the contact oxidation reaction more complete, the biological contact oxidation tank 2 is designed as an overall central island-like ring-shaped oxidation ditch structure, and the central island is provided with the sedimentation tank 6 and the The adsorption dephosphorization pool 7 is described, so that the contact oxidation pool, sedimentation tank, and adsorption dephosphorization pool can be collected in one treatment pool, and an aerobic-anaerobic flow that contacts the oxidation pool can be formed around the central island, which can promote the continuous circulation of sewage Anaerobic-Aerobic Reaction.

In order to improve the sedimentation treatment efficiency and further make the equipment occupy a small area, a sloping plate sedimentation tank can be selected. The effluent after biological contact oxidation treatment enters from the water distribution area 16 of the sloping plate sedimentation tank, and realizes mud-water separation through the sloping plate area 17. The separated clean water enters the clean water area 18, and is further introduced into the adsorption dephosphorization tank 7 through pipelines, and the mud is separated and stored in the mud storage hopper 19, which is provided with a sludge discharge pipe for discharging sludge.

The biofilter 1 is filled with suspended fillers that have the advantages of large specific surface area, strong impact resistance, easy film formation, and high biological activity. In order to prevent the suspended fillers 20 filled in the biofilter from being taken away by the water flow during treatment and effluent , the bottom of the biological filter 1 is provided with a support layer 21 for supporting the suspended filler 20; to further ensure the aeration effect during the treatment process of the biological filter 1, several rows of natural ventilation holes are arranged on the side of the biological filter 1 In order to realize natural ventilation and aeration, as an optimization, the total area of the natural ventilation holes accounts for 3% of the cross-sectional area of the biofilter 1, so as to provide dissolved oxygen required for microbial growth and ensure better biological treatment effect.

Both the aerobic zone 9 and the anaerobic zone 10 of the biological contact oxidation tank 2 are equipped with three-dimensional elastic fillers 22 that are easy to hang film, withstand high load impact, have good treatment effect, long service life, and are not easy to be blocked. Aerobic microorganisms are hung in the oxygen zone, and anaerobic microorganisms are hung in the anaerobic zone to realize the cyclic aerobic-anaerobic reaction of sewage in the biological contact oxidation tank.

The following is a detailed description of the method of using the equipment of this embodiment to treat sewage. In the following embodiment, domestic sewage from student dormitories is used for treatment. During the treatment process, the rated displacement of the aeration pump is set to 300 L/min.

Example 1

Using the method of the present invention to treat domestic sewage in student dormitories, the raw water quality of sewage: CODcr: 283mg/L, NH ⁺ -N: 34mg/L, TN: 53 mg/L, TP: 3.6mg/L.

1) The domestic sewage in the student dormitory is uniformly collected by the pipeline system and then poured into the septic tank for preliminary filtration, sedimentation and hydrolysis, and then the septic tank effluent is drained to the grid tank through the pipeline;

2) After the suspended impurities in the sewage are removed in the grid pool, it is poured into the regulating pool for regulation and storage;

3) Use a water pump to lift the sewage in the regulating tank to the biofilter, and spread it evenly on the surface of the biofilter through perforated water pipes. The HRT of the biofilter is 5.5 hours, and it is degraded by microorganisms attached to the suspended filler. Removal of some organic matter in sewage;

4) The effluent of the biological filter enters the biological contact oxidation tank under the action of gravity, and the body of the biological contact oxidation tank is equipped with three-dimensional elastic fillers, which are divided into anaerobic and aerobic sections. The anaerobic section mainly performs denitrification and phosphorus release Reaction, the aerobic section mainly carries out nitrification, excessive phosphorus uptake and organic matter degradation reactions. The HRT of the biological contact oxidation tank is 24 hours, the gas-water ratio is 12, and the hydraulic load is 0.075 m³/(m ² ·h).

5) The effluent from the biological contact oxidation tank enters the inclined plate sedimentation tank through the pipeline, and the water flows from bottom to top to realize the separation of mud and water;

6) The effluent of the supernatant from the inclined plate sedimentation tank enters the adsorption phosphorus removal tank, and the filling amount of the modified steel slag is 5 g/100 mL of sewage, and the advanced treatment of phosphorus is realized under the adsorption of the steel slag.

After the sewage is treated by the method of this embodiment, the effluent water quality is: CODcr: 19mg/L, NH ⁺ -N: 2.9mg/L, TN: 8.7 mg/L, TP: 0.15mg/L. It meets the first-class A discharge standard of "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB 18918-2002).

Example 2

The method of the present invention is used to treat domestic sewage in student dormitories. The raw water quality of sewage is: CODcr: 354mg/L, NH ⁺ -N: 46mg/L, TN: 62 mg/L, TP: 4.8mg/L.

1) The domestic sewage in the student dormitory is uniformly collected by the pipeline system and then poured into the septic tank for preliminary filtration, sedimentation and hydrolysis, and then the septic tank effluent is drained to the grid tank through the pipeline;

2) After the suspended impurities in the sewage are removed in the grid pool, it is poured into the regulating pool for regulation and storage;

3) Use a water pump to lift the sewage in the regulating tank to the biofilter, and spread it evenly on the surface of the biofilter through perforated water pipes. The HRT of the biofilter is 3.3 hours, and it is degraded by microorganisms attached to the suspended filler. Removal of some organic matter in sewage;

4) The effluent of the biological filter enters the biological contact oxidation tank under the action of gravity, and the body of the biological contact oxidation tank is equipped with three-dimensional elastic fillers, which are divided into anaerobic and aerobic sections. The anaerobic section mainly performs denitrification and phosphorus release Reaction, the aerobic section mainly carries out nitrification, excess phosphorus uptake, and organic matter degradation reactions. The HRT of the biological contact oxidation tank is 14.4 hours, the gas-water ratio is 9, and the hydraulic load is 0.125 m³/(m ² ·h).

5) The effluent from the biological contact oxidation tank enters the inclined plate sedimentation tank through the pipeline, and the water flows from bottom to top to realize the separation of mud and water;

6) The effluent of the supernatant from the inclined plate sedimentation tank enters the adsorption phosphorus removal tank, and the filling amount of the modified steel slag is 5 g/100 mL of sewage, and the advanced treatment of phosphorus is realized under the adsorption of the steel slag.

After the sewage is treated by the method of this embodiment, the effluent water quality is: CODcr: 24mg/L, NH ⁺ -N: 4.1mg/L, TN: 10.5 mg/L, TP: 0.18mg/L. It meets the first-class A discharge standard of "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB 18918-2002).

Example 3

Using the method of the present invention to treat domestic sewage in student dormitories, the raw water quality of the sewage: CODcr: 420mg/L, NH ⁺ -N: 52mg/L, TN: 75 mg/L, TP: 5.2mg/L.

1) The domestic sewage in the student dormitory is uniformly collected by the pipeline system and then poured into the septic tank for preliminary filtration, sedimentation and hydrolysis, and then the septic tank effluent is drained to the grid tank through the pipeline;

2) After the suspended impurities in the sewage are removed in the grid pool, it is poured into the regulating pool for regulation and storage;

3) Use a water pump to lift the sewage in the regulating tank to the biofilter, and spread it evenly on the surface of the biofilter through perforated water pipes. The HRT of the biofilter is 3.3 hours, and it is degraded by microorganisms attached to the suspended filler. Removal of some organic matter in sewage;

4) The effluent of the biological filter enters the biological contact oxidation tank under the action of gravity, and the body of the biological contact oxidation tank is equipped with three-dimensional elastic fillers, which are divided into anaerobic and aerobic sections. The anaerobic section mainly performs denitrification and phosphorus release Reaction, the aerobic section mainly carries out nitrification, excessive phosphorus uptake and organic matter degradation reactions. The HRT of the biological contact oxidation tank is 14.4 hours, the gas-water ratio is 12, and the hydraulic load is 0.125 m³/(m ² ·h).

5) The effluent from the biological contact oxidation tank enters the inclined plate sedimentation tank through the pipeline, and the water flows from bottom to top to realize the separation of mud and water;

6) The effluent of the supernatant from the inclined plate sedimentation tank enters the adsorption phosphorus removal tank, and the filling amount of the modified steel slag is 3 g/100 mL sewage, and the advanced treatment of phosphorus is realized under the adsorption of the steel slag.

After the sewage is treated by the method of this embodiment, the effluent water quality is: CODcr: 22mg/L, NH ⁺ -N: 3.8mg/L, TN: 10.2 mg/L, TP: 0.24mg/L. It meets the first-class A discharge standard of "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB 18918-2002).

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.

Claims (10)

1. biofilter-bio-contact oxidation-slag adsorption sewage treatment system, including biofilter, biological contact oxidation pond, Hydraulic Circulation pump, aeration tube, aeration pump and sedimentation tank, it is characterized in that: also include being internally provided with the adsorption and dephosphorization pond of slag packing layer, described biofilter is provided with water inlet, the outlet of biofilter is connected with described biological contact oxidation pond, described biological contact oxidation pond includes aerobic zone and anaerobic zone, described Hydraulic Circulation pump connects described aerobic zone and anaerobic zone, described aeration tube is arranged on bottom described aerobic zone, described aeration pump is connected to realize aeration with described aeration tube, described biological contact oxidation pond is connected with the water inlet of sedimentation tank, the outlet of described sedimentation tank is connected with the water inlet in described adsorption and dephosphorization pond, described adsorption and dephosphorization pond is provided with outlet.

Biofilter-bio-contact oxidation-slag adsorption sewage treatment system the most according to claim 1, it is characterised in that: described biofilter is provided above water distributor of boring a hole, and described perforation water distributor is connected with the water inlet of biofilter.

Biofilter-bio-contact oxidation-slag adsorption sewage treatment system the most according to claim 1, it is characterised in that: described biofilter is arranged on the top of described biological contact oxidation pond.

Biofilter-bio-contact oxidation-slag adsorption sewage treatment system the most according to claim 1, it is characterized in that: described biological contact oxidation pond is the overall annular oxidation ditch structure in central authorities' island, and described Center Island is provided with described sedimentation tank and described adsorption and dephosphorization pond.

Biofilter-bio-contact oxidation-slag adsorption sewage treatment system the most according to claim 1, it is characterised in that: multiple rows of slag packing layer it is disposed with along described adsorption and dephosphorization pond water inlet to outlet direction.

Biofilter-bio-contact oxidation-slag adsorption sewage treatment system the most according to claim 1, it is characterised in that: the slag filled in described adsorption and dephosphorization pond is for processing 24 h, and the modified steel scoria obtained after dry 1 h at 700 DEG C through aqueous slkali soaking.

7. use the method that the arbitrary described biofilter-bio-contact oxidation-slag adsorption sewage treatment system of claim 1 ~ 6 carries out sewage disposal, it is characterised in that comprise the steps:

1) sewage is introduced dross removing device and removes the suspended impurity in sewage；

2) sewage after step 1) being processed imports in regulating reservoir and regulates and stores；

3) by step 2) regulate and store after water outlet pump in described biofilter, remove partial organic substances in water by the Degradation of microorganism on floating stuffing in biofilter；

4) water outlet after step 3) being processed introduces in described biological contact oxidation pond, alternately anaerobic-aerobic reaction is carried out under the Circulation of Hydraulic Circulation pump, anti-nitration reaction and the anaerobic phosphorus release reaction of nitrogen is completed under the anaerobe effect of anaerobic zone, complete the nitration reaction of nitrogen under the aerobic bacteria effect of aerobic zone, aerobic excess inhales phosphorus reaction and organic matter degradation reaction, removes Organic substance, nitrogen and the phosphorus in sewage；

5) water outlet after step 4) being processed introduces in sedimentation tank, it is achieved mud-water separation；

6) water outlet after step 5) being processed introduces in described adsorption and dephosphorization pond, utilizes slag filler that the phosphorus in sewage is carried out degree of depth removal.

Use the method that biofilter-bio-contact oxidation-slag adsorption sewage treatment system carries out sewage disposal the most according to claim 7, it is characterised in that in step 3), the hydraulic detention time of biofilter is 2 ~ 6 hours.

Use the method that biofilter-bio-contact oxidation-slag adsorption sewage treatment system carries out sewage disposal the most according to claim 7, it is characterized in that, the hydraulic detention time of step 4) biological contact oxidation pond is 10 ~ 24 hours, running gas-water ratio is 9 ~ 15, and hydraulic load is 0.075 ~ 0.175m/(m²H).

Use the method that biofilter-bio-contact oxidation-slag adsorption sewage treatment system carries out sewage disposal the most according to claim 7, it is characterized in that, step 6) adsorption and dephosphorization pond uses 1 ~ 5 g slags to carry out the filling of slag packing layer according to often processing 100 mL waste water.