CN106927640B - Sewage treatment method - Google Patents

Abstract

The invention provides a sewage treatment method, wherein a biochemical pool group comprises a plurality of biochemical pools which are communicated in sequence, and the bottom of each biochemical pool is provided with a sedimentation pool; the sewage treatment device comprises a biochemical tank group, a biochemical liquid pretreatment device connected with a biochemical liquid inlet, a sedimentation tank or a dehydration device connected with a heavy component outlet and a dosing device connected with a light component outlet; the sewage treatment method comprises the following steps: biochemical liquid enters the biochemical tank group through a biochemical liquid inlet, and under the action of the height drop of the biochemical tank, the biochemical liquid passes through the anaerobic biochemical tank, the anoxic biochemical tank and the four aerobic biochemical tanks in an overflow mode, and finally the light mud is discharged through a light component outlet; and the heavy mud flows from the first aerobic biochemical tank to the anaerobic biochemical tank under the action of the conveying equipment, and finally the heavy mud is discharged through a heavy component outlet. The invention has simple structure, low cost and small occupied area, and can ensure to achieve the expected effect of treatment.

Description

Sewage treatment method

Technical Field

The invention belongs to the technical field of sewage treatment, and particularly relates to a sewage treatment method.

Background

With the improvement of environmental requirements, the treatment and discharge of urban and industrial sewage are highly regarded, if the treatment is carried out by adopting the traditional sewage treatment method, the treatment effect is difficult to reach the stable effluent index, the treatment cost is higher, and the treatment is difficult to enlarge when the proportion of the industrial sewage is large.

The prior art generally adopts a biochemical tank and a secondary sedimentation tank (namely, a secondary sedimentation tank which is an important component of an activated sludge system and mainly has the functions of separating sludge, clarifying, concentrating and refluxing mixed liquid with activated sludge, and directly influencing the effluent quality and the concentration of the refluxed sludge of the activated sludge system) as a reaction tank and a sedimentation tank for biochemical reaction, and the prior art has the following defects:

the first sedimentation tank, the biochemical tank and the second sedimentation tank occupy too large area and have messy structures due to disordered placement.

Secondly, for the reasons, sludge is discharged from a single biochemical tank or a secondary sedimentation tank, organic matters in the sludge are difficult to fully utilize, the discharged heavy sludge is excessive, and the sludge treatment cost is too high.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

The object of the present invention is to provide a method for treating waste water, which solves at least one of the two problems to a large extent.

The invention aims to provide a biochemical pool group.

The second purpose of the invention is to provide a sewage treatment device.

The third purpose of the invention is to provide a sewage treatment method.

On one hand, the biochemical pool group provided by the invention comprises a plurality of biochemical pools which are communicated in sequence, and a sedimentation pool is arranged at the bottom of each biochemical pool.

Further, any two adjacent sedimentation tanks are communicated through conveying equipment.

Further, the conveying equipment comprises a conveying pipe and a conveying mechanism;

the conveying pipe is used for conveying the heavy mud in the sedimentation tank, and both ends of the conveying pipe are respectively provided with a heavy component suction inlet and a heavy component discharge outlet;

the conveying mechanism is arranged in the conveying pipe and comprises a driving mechanism and an impeller, the driving mechanism drives the impeller to rotate, and heavy mud is conveyed by negative pressure formed in the conveying pipe.

Furthermore, a biochemical pool positioned at the starting end of the biochemical pool group is provided with a biochemical liquid inlet and a heavy component outlet; the biochemical pool positioned at the tail end of the biochemical pool group is provided with a light component outlet;

the biochemical liquid inlet and the light component outlet are arranged above the mud-water separation line, and the heavy component outlet is arranged below the mud-water separation line.

Furthermore, the biochemical tank at the starting end of the biochemical tank group is an anaerobic biochemical tank, and the biochemical tank at the tail end of the biochemical tank group is an aerobic biochemical tank.

Further, along the direction from the biochemical liquid inlet to the light component outlet, the heights of the biochemical pool and the sedimentation pool are sequentially reduced.

Further, the device comprises six biochemical tanks which are sequentially connected, wherein the six biochemical tanks are an anaerobic biochemical tank, an anoxic biochemical tank and four aerobic biochemical tanks in sequence.

Furthermore, a plurality of stirrers and aeration pipes are arranged in the anaerobic biochemical tank and the anoxic biochemical tank; and a plurality of aeration pipes are arranged in the four aerobic biochemical tanks.

On the other hand, the invention also provides a sewage treatment device, which comprises the biochemical tank group, a biochemical liquid pretreatment device connected with the biochemical liquid inlet, a sedimentation tank or a dehydration device connected with the heavy component outlet and a dosing device connected with the light component outlet.

Finally, the invention provides a sewage treatment method using the sewage treatment device, which comprises the following steps:

biochemical liquid enters the biochemical pool group through a biochemical liquid inlet;

under the action of the height difference of the biochemical tanks, the biochemical liquid flows through the anaerobic biochemical tank, the anoxic biochemical tank and the four aerobic biochemical tanks in an overflow mode, and finally the light mud is discharged through the light component outlet and enters the front end of the dosing device;

and the heavy mud is conveyed from the sedimentation tank at the bottom of the first aerobic biochemical tank to the sedimentation tank at the bottom of the anaerobic biochemical tank under the action of the conveying equipment, and finally the heavy mud is discharged through a heavy component outlet and enters the sedimentation tank or the dehydration device.

The invention has the beneficial effects that:

on one hand, the invention provides a biochemical pool group, which consists of a plurality of biochemical pools communicated in sequence, wherein a sedimentation pool is arranged at the bottom of each biochemical pool; the whole system consists of a plurality of biochemical tanks, and a sedimentation tank is arranged in each biochemical tank, so that the traditional biochemical tank and the secondary sedimentation tank are completely integrated, the floor area is small, the whole system is uniformly arranged, and the space is saved;

in addition, as the plurality of biochemical tanks are connected in sequence and the sedimentation tank is arranged in the biochemical tanks, the sludge can be fully decomposed in the whole system, the organic matters (such as carbon sources and the like) in the biochemical tanks can be fully utilized in the reaction, and the system does not need to additionally increase the organic matters (such as carbon sources and the like);

finally, because the organic matters in the heavy mud can be fully utilized in the reaction process, the mud discharge amount of the whole system can be greatly reduced, the sludge amount to be treated is also greatly reduced, the cost for treating the sludge can be reduced, and the economic benefit is good.

On the other hand, the invention also provides a sewage treatment device, which comprises the biochemical tank group, a biochemical liquid pretreatment device connected with the biochemical liquid inlet, a sedimentation tank or a dehydration device connected with the heavy component outlet and a dosing device connected with the light component outlet.

Finally, the biochemical liquid conveying method provided by the invention has all the advantages of the sewage treatment device due to the application of the sewage treatment device, in addition, the light component outlet and the heavy component outlet are adopted, so that the light mud and the heavy mud are respectively discharged, the light mud can be continuously subjected to mud-water separation at the front end of the reaction, the heavy mud can be directly treated, the treatment efficiency of the system is improved, the light mud and the heavy mud are separately treated, the mud-water ratio and the mud production quality are not required to be manually monitored, and the cost is saved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic structural diagram of a biochemical pool according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a first internal structure of a biochemical pool according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a second internal structure of a biochemical pool according to an embodiment of the invention;

FIG. 4 is a schematic diagram of a third internal structure of a biochemical pool according to an embodiment of the invention;

FIG. 5 is a schematic diagram illustrating a connection relationship between any two biochemical pools according to a first embodiment of the present invention;

FIG. 6 is a schematic structural view of a biochemical tank set applied in a sewage treatment device according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a conveying apparatus according to an embodiment of the present invention shown in fig. 1.

Icon: 100-biochemical pool group; 101-a biochemical pool; 1011-aerobic biochemical tank; 1012-anoxic biochemical tank; 1013-anaerobic biochemical pool; 102-an aerator pipe; 103-a stirrer; 104-biochemical fluid inlet; 105-a heavies outlet; 106-light fraction outlet; 107-a conveying device; 1071-delivery tube; 1072-impeller; 1073 — a drive mechanism; 108-a transport channel; 200-a mud-water separation line.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example one

As shown in fig. 1 to 6, the biochemical pool 100 provided by the present invention provided by this embodiment is composed of a plurality of biochemical pools 101 communicated in sequence, and a sedimentation pool (not shown) is provided at the bottom of each biochemical pool 101.

It should be noted that, in the embodiment, the traditional biochemical tank 101 and the secondary sedimentation tank system are integrated, so that the occupied area is small, the arrangement is uniform on the whole, and the space is saved;

in addition, as the plurality of biochemical tanks 101 are connected in sequence and the sedimentation tank is arranged in the biochemical tanks, the sludge can be fully decomposed in the whole system, the organic substances (such as carbon sources and the like) in the biochemical tanks can be fully utilized in the reaction in the biochemical tanks, and the system does not need to additionally increase the organic substances (such as carbon sources and the like);

finally, because the organic matters in the heavy mud can be fully utilized in the reaction process, the mud discharge amount of the whole system can be greatly reduced, the sludge amount to be treated is also greatly reduced, the cost for treating the sludge can be reduced, and the economic benefit is good.

The sludge treatment method mainly comprises the following four steps:

sanitary landfill

The advantages of sanitary landfill include low investment, quick implementation, simple method and large treatment scale, and the disadvantages include high requirement on soil mechanical property of sludge, large area of field and large transport degree, and need of anti-seepage treatment for ground to prevent groundwater pollution. At present, landfill is one of the important methods for sludge treatment in China, but in the long run, conventional landfill is an irreversible final treatment mode, large-area land is needed, and the application proportion of the conventional landfill is gradually reduced. And (3) landfill cost: 250 yuan per ton, wherein the curing treatment cost (including investment) is 110 yuan.

Secondly, sludge composting

An important aspect of sludge composting in agriculture is the process of fermentation using microorganisms in the sludge. This technology was successfully developed in europe as early as the 20 th century and was only used for municipal waste treatment, and this method was introduced later for sludge treatment and application to agricultural fields.

Land utilization (sludge agricultural)

The method is a treatment method which accords with the national conditions of China and is based on the fertilizer efficiency utilization factor regardless of economic factors in China. Sludge agriculture is the most feasible and realistic disposal scheme from the detailed situation of China. The sludge can be treated in a large amount in agriculture, and can be used for farmlands only when the sludge reaches the relevant national scale in principle; the sludge is involved in the natural substance recycling process of the farmland, and nitrogen, phosphorus, potassium, organic matters and trace elements in the sludge are good agricultural fertilizers and have the effect of increasing the yield of crops; organic matters and humus in the sludge can improve the soil structure, and the sludge is a good soil modifier; the agricultural utilization of the sludge reduces the output utilization degree and is suitable for the current economic development condition of China.

Fourthly, sludge incineration

After the sludge is incinerated, the reduction is greatly realized. In addition, heavy metals contained in the sludge are oxidized into oxides which are not disordered at high temperature, and the heavy metals are excellent materials for manufacturing products such as ceramic grains, ceramic tiles and the like. In recent years, the burning method has been greatly developed, and compared with other methods, the burning method has the following advantages: the volume and weight of the sludge are greatly reduced, so that substances which need to be treated in the end are very small, and sometimes incineration ash can be made into useful products; the sludge treatment speed is high, and long-term storage is not needed; the sludge can be incinerated on site without long interval transportation; energy can be recovered for power generation and heat supply. Cost of incineration: the total cost is 245-.

It should be noted that, with the biochemical tank 100 of this embodiment, the sludge output can be reduced by at least about 50%, thereby greatly reducing the cost of sludge treatment.

Specifically, the following is a detailed description of each specific structure of the biochemical liquid delivering apparatus 107 in the present embodiment:

in this embodiment, as shown in fig. 7, any two adjacent sedimentation tanks are communicated with each other through a conveying device 107. The conveying device 107 comprises a conveying pipe 1071 and a conveying mechanism; a conveying pipe 1071 for conveying heavy mud in the sedimentation tank, both ends of which are respectively provided with a heavy component suction port and a heavy component discharge port; conveying mechanism establishes inside conveyer pipe 1071, including actuating mechanism 1073 and impeller 1072, actuating mechanism 1073 drives the impeller 1072 and rotates to conveying pipe 1071 is inside to form the negative pressure and carry heavy mud.

It should be pointed out that the conveying mechanism of this embodiment has adopted the impeller to replace the water pump, and the impeller rotates, and the inside negative pressure that forms of conveyer pipe 1071, the inside vacuum state that becomes of conveyer pipe 1071, the heavy mud that needs to transport inhales through the heavy ends sunction inlet, discharges through the heavy ends discharge port, and the lift that whole process needs is lower, and because the impeller does not need complicated seal structure, the energy that its consumed also greatly reduced, consequently, it has low energy consumption and space-saving effect.

It should also be noted that the conveying equipment 107 is responsible for connecting two adjacent sedimentation tanks, and the conveying equipment 107 with low energy consumption is used for conveying heavy mud in the sedimentation tank to a front sedimentation tank in the counter-current direction, so that the internal and external refluxes of the mud are combined, and no external reflux is realized.

In this embodiment, the biochemical pool 101 located at the beginning of the biochemical pool 100 is provided with a biochemical liquid inlet 104 and a heavy component outlet 105; the biochemical pool 101 at the tail end of the biochemical pool 100 is provided with a light component outlet 106. The heights of the biochemical tank 101 and the sedimentation tank are sequentially reduced along the direction from the biochemical solution inlet 104 to the light component outlet 106.

It should be pointed out that, biochemical liquid is through the mode of overflow forward discharge against the water flow direction, utilizes the setting of natural difference in height, and biochemical liquid need not external energy loss, can automatic overflow transport, and to a great extent has reduced the energy consumption.

It should also be pointed out that the sludge discharged into the biochemical system after treatment has good settling property, fast settling speed and good activity, can effectively remove organic pollutants and pollutants difficult to degrade in the wastewater, has strong capability of adsorbing and oxidizing organic matters, and the tank body is perforated, and heavy sludge is conveyed in the reverse water flow direction by the low-energy sludge conveying equipment 107, so that the activated sludge is recycled and fully utilized until the dead sludge and the heavy sludge are discharged.

In an alternative of this embodiment, the biochemical pool 100 includes six biochemical pools 101 connected in sequence, and the six biochemical pools 101 are an anaerobic biochemical pool 1013, an anoxic biochemical pool 1012 and four aerobic biochemical pools 1011 in sequence.

Wherein, two heavy component outlets 105 are arranged in the anaerobic biochemical tank 1013, and heavy mud and dead mud are discharged from the heavy component outlets; light mud and mud with high activity are continuously left in the system for cyclic utilization, and an inclined plate is additionally arranged in a nitrifying liquid reflux area to form internal reflux, so that nitrifying liquid and active mud are continuously and circularly and fully utilized, and a design method of the low-energy-consumption multistage biological reaction tank without external reflux and a secondary sedimentation tank is formed.

Wherein, a plurality of stirrers 103 and aeration pipes 102 (denitrification) are arranged in the anaerobic biochemical tank 1013 and the anoxic biochemical tank 1012.

Wherein, a plurality of aeration pipes 102 (for removing BOD, nitrifying and absorbing phosphorus) are arranged in the four aerobic biochemical tanks 1011.

It is to be noted that aeration refers to a process of forcibly transferring oxygen in the air into the liquid, with the purpose of obtaining sufficient dissolved oxygen. In addition, the aeration also can prevent the suspension in the tank from sinking and strengthen the contact of the organic matters in the tank with microorganisms and dissolved oxygen. Thereby ensuring the oxidative decomposition of the organic matters in the sewage by the microorganisms in the tank under the condition of sufficient dissolved oxygen.

It should be noted that the construction of the traditional process leads the sludge and sewage to enter the anaerobic reaction tank of the biochemical system after being pretreated, the sewage and the phosphorus-containing return sludge in the system enter synchronously, the main function of the sewage treatment device of the embodiment is to release phosphorus, and simultaneously part of nitrogen-containing organic matters are aminated; the first function of the anoxic biochemical tank 1012 and the anaerobic biochemical tank 1013 is denitrification, and nitrate nitrogen is sent from the aerobic biochemical tank 1011 through internal circulation; the aerobic biochemical tank 1011 (aeration pipe 102) is multifunctional, and BOD removal, nitrification, phosphorus absorption, and the like are all performed therein. The purpose of this embodiment is to improve the traditional process, preserve and perfect to achieve better treatment effect. In the embodiment, the nitrogen and phosphorus removal capability is enhanced by means of circulation in the biochemical tank 101, so that the activated sludge can be fully utilized.

It should be further noted that, in this embodiment, each of the biochemical tanks 101 is internally provided with a sedimentation tank, which is an independent purification system, and the plurality of biochemical tanks 101 are connected, so that the biochemical tanks are strong in impact resistance and good in stability, and the effluent quality can reach the monitoring-free effect, and can reach the standard stably, thereby reducing the cost.

Example two

On the basis of the first embodiment, the present embodiment further provides a sewage treatment apparatus, which includes the biochemical tank set 100, a biochemical liquid pretreatment apparatus connected to the biochemical liquid inlet 104, a sedimentation tank or a dehydration apparatus connected to the heavy component outlet 105, and a chemical adding apparatus connected to the light component outlet 106.

The working principle of the embodiment is as follows:

after being treated by the biochemical liquid pretreatment device, the biochemical liquid is sequentially conveyed to an anaerobic biochemical tank 1013, an anoxic biochemical tank 1012 and four aerobic biochemical tanks 1011 through an overflow conveying mode (liquid or mixture flows from a high position to a low position and is called as overflow), sedimentation is performed in each biochemical tank 101 to realize sludge-water separation, light sludge on the upper layer is discharged through a light component outlet 106 and enters the front end of the chemical adding device, heavy sludge is sequentially conveyed to the anaerobic biochemical tank 1013 from the last aerobic biochemical tank 1011 under the action of a conveying device 107, and heavy sludge is discharged through a heavy component outlet 105 of the anaerobic biochemical tank 1013 through the conveying device 107 to be treated.

With continued reference to fig. 5, the heavy component outlet 105 is disposed below the muddy water separation line 200, the light component outlet 106 and the biochemical liquid inlet 104 are disposed above the muddy water separation line 200, and the conveying device 107 is disposed below the muddy water separation line 200.

It should be noted that the sewage treatment apparatus provided by this embodiment includes the biochemical tank set 100, so that it has all the advantages of the biochemical liquid delivery device 107, and thus will not be described herein.

EXAMPLE III

As shown in fig. 1 to 4, on the basis of the second embodiment, the present embodiment provides a sewage treatment method using the sewage treatment apparatus, which includes the following steps:

s001: biochemical fluid enters the biochemical reservoir 100 through a biochemical fluid inlet 104;

s002: under the action of height drop, the biochemical liquid flows through an anaerobic biochemical tank 1013, an anoxic biochemical tank 1012 and four aerobic biochemical tanks 1011 in an overflow manner, and finally the light mud is discharged through a light component outlet 106 and enters the front end of the dosing device;

s003: the heavy mud is conveyed from the sedimentation tank at the bottom of the first aerobic biochemical tank 1011 to the sedimentation tank at the bottom of the anaerobic biochemical tank 1013 through the conveying device 107 under the action of the conveying device 107, and finally the heavy mud is discharged through the heavy component outlet 105 and enters the sedimentation tank or the dehydration device.

It should be noted that the sewage treatment method provided by the embodiment employs the sewage treatment apparatus, so that the method has all the advantages of the sewage treatment apparatus, and thus, the details are not repeated herein.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (1)

1. A sewage treatment method is characterized by being applied to a sewage treatment device, wherein the sewage treatment device comprises a biochemical tank group, the biochemical tank group comprises a plurality of biochemical tanks which are sequentially communicated, a sedimentation tank is arranged at the bottom of each biochemical tank, any two adjacent sedimentation tanks are communicated through conveying equipment, and the conveying equipment comprises a conveying pipe and a conveying mechanism; the conveying pipe is used for conveying heavy mud in the sedimentation tank, and both ends of the conveying pipe are respectively provided with a heavy component suction inlet and a heavy component discharge outlet; the conveying mechanism is arranged in the conveying pipe and comprises a driving mechanism and an impeller, and the driving mechanism drives the impeller to rotate so as to form negative pressure in the conveying pipe to convey heavy mud;

the number of the biochemical tanks is six, the six biochemical tanks are an anaerobic biochemical tank, an anoxic biochemical tank and four aerobic biochemical tanks in sequence, the biochemical tank at the starting end of the biochemical tank group is the anaerobic biochemical tank, and the biochemical tank at the tail end of the biochemical tank group is the aerobic biochemical tank; the biochemical pool positioned at the starting end of the biochemical pool group is provided with a biochemical liquid inlet and a heavy component outlet; the biochemical pool positioned at the tail end of the biochemical pool group is provided with a light component outlet; the biochemical liquid inlet and the light component outlet are arranged above a mud-water separation line, and the heavy component outlet is arranged below the mud-water separation line; the heights of the biochemical pool and the sedimentation pool are sequentially reduced along the direction from the biochemical liquid inlet to the light component outlet;

the sewage treatment device also comprises a biochemical liquid pretreatment device connected with the biochemical liquid inlet, a sedimentation tank or a dehydration device connected with the heavy component outlet and a dosing device connected with the light component outlet;

the sewage treatment method comprises the following steps:

biochemical liquid enters the biochemical pool group through a biochemical liquid inlet;

under the action of the height difference of the biochemical tanks, the biochemical liquid flows through the anaerobic biochemical tank, the anoxic biochemical tank and the four aerobic biochemical tanks in an overflow mode, and finally the light mud is discharged through the light component outlet and enters the front end of the dosing device;

and the heavy mud is conveyed from the sedimentation tank at the bottom of the first aerobic biochemical tank to the sedimentation tank at the bottom of the anaerobic biochemical tank under the action of the conveying equipment, and finally the heavy mud is discharged through a heavy component outlet and enters the sedimentation tank or the dehydration device.

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