Heavy oil sewage treatment device and method

Abstract

The invention relates to a heavy oil sewage treatment device. The device comprises a sewage treatment tank; comprising a heavy carrier and is arranged at the bottom of one side of the sewage treatment tank; the aeration device is arranged above the sludge; the flow pushing device is arranged at the bottom of the sewage treatment tank; the sewage inlet is formed in one side of the sewage treatment tank and is arranged above the aeration device; the sewage outlet is formed in the other side of the sewage treatment tank and is arranged above the aeration device. According to the heavy oil sewage treatment device and method provided by the invention, the sludge is formed by using the heavy carrier, the sludge is deposited at the bottom of the sewage treatment tank, and the sludge and the sewage are separated through the aeration device, so that the content of dissolved oxygen in the sludge is relatively low, and the content of dissolved oxygen in the sewage is relatively high; therefore, an aerobic biochemical reaction and an anaerobic biochemical reaction can be simultaneously carried out in the sewage treatment tank, and effective treatment of heavy oil sewage is realized.

Description

Technical Field

[0001] The present application relates to the field of environmental protection, and in particular to sewage treatment. Background Art

[0002] Heavy oil wastewater in oil fields is a product of the water system after the oil-water separation in the gathering and transportation system, and belongs to the series of mixtures of heavy oil production wastewater and associated water. In the process of heavy oil extraction, the development methods and approaches are diverse and basically accompanied by a high-temperature environment, resulting in the presence of a large amount of organic matter and a large amount of soluble inorganic metal ion compounds in the heavy oil wastewater. Due to the characteristics of heavy crude oil, most of the organic matter in the heavy oil wastewater is wax, asphaltene, colloid and other impurities. The widespread collection and separation characteristics of heavy oil wastewater are manifested in the macroscopic form of high emulsification, high mineralization, high salinity, and high ionicity. In addition, due to the complex geology and formations, the system of heavy oil wastewater is poor and the stability is not high. Therefore, it is extremely difficult for heavy oil wastewater to achieve compliance discharge. Summary of the invention

[0003] The embodiments of the present application provide a device and method for treating heavy oily wastewater to solve the technical problem that the treatment of heavy oily wastewater is difficult.

[0004] In a first aspect, an embodiment of the present application provides a heavy oil wastewater treatment device, the heavy oil wastewater treatment device comprising:

[0005] sewage treatment tanks;

[0006] The sludge including the heavy carrier is arranged at the bottom of one side of the sewage treatment tank;

[0007] an aeration device, arranged above the sludge;

[0008] A flow-pushing device is arranged at the bottom of the sewage treatment tank;

[0009] A sewage inlet is arranged on one side of the sewage treatment tank and above the aeration device;

[0010] The sewage outlet is arranged at the other side of the sewage treatment tank and above the aeration device.

[0011] In some embodiments of the present application, the heavy oil wastewater treatment device further includes a primary secondary sedimentation tank, and the sewage outlet is connected to the primary secondary sedimentation tank.

[0012] In some embodiments of the present application, the heavy oil wastewater treatment device also includes a secondary aerobic tank and a secondary secondary sedimentation tank connected to each other, the primary secondary sedimentation tank is connected to the secondary aerobic tank, and the secondary secondary sedimentation tank is connected to the sewage inlet.

[0013] In some embodiments of the present application, the heavy oil wastewater treatment device further includes a sludge circulation pipe, which is arranged at the bottom of one side of the wastewater treatment tank, and the primary secondary sedimentation tank is connected to the sludge circulation pipe.

[0014] In a second aspect, an embodiment of the present application provides a method for treating heavy oily wastewater, wherein the method for treating heavy oily wastewater is implemented by the heavy oily wastewater treatment device described in the first aspect, and the method for treating heavy oily wastewater comprises the following steps:

[0015] Introducing sewage from the sewage inlet into the sewage treatment tank, adding a heavy carrier into the sewage treatment tank, and forming sludge from the heavy carrier;

[0016] Running the aeration device to increase the oxygen content of the sewage above the aeration device so that the sewage above the aeration device undergoes an aerobic biochemical reaction;

[0017] Allowing the sludge below the ventilation device to undergo anaerobic biochemical reaction;

[0018] The sludge at the bottom of the sewage treatment tank is pushed to the upper part of the sewage treatment device by the flow pushing device, mixed with the sewage after aerobic biochemical reaction to form primary treated sewage, and discharged through the sewage outlet.

[0019] In some embodiments of the present application, the primary treated sewage enters the primary secondary sedimentation tank through the sewage outlet, then enters the secondary aerobic tank for aerobic biochemical reaction, then enters the secondary secondary sedimentation tank, and circulates back to the sewage treatment tank through the sewage inlet.

[0020] In some embodiments of the present application, the primary treated sewage enters the primary secondary sedimentation tank through the sewage outlet and then circulates back to the sewage treatment tank through the sludge circulation pipe.

[0021] In some embodiments of the present application, when the sewage is treated in a sewage treatment tank,

[0022] The hydraulic retention time is 13-15h; and / or,

[0023] COD load is 10.8-16.8kg / (m 3 d); and / or,

[0024] The liquid phase pH is 7.0-7.5; and / or,

[0025] The water temperature is 25-30°C; and / or,

[0026] The suspended sludge concentration is 11000-13000 mg / L.

[0027] In some embodiments of the present application, the dissolved oxygen concentration of the sewage above the aeration device is 6-8 mg / L; and / or,

[0028] The dissolved oxygen concentration in the anaerobic environment below the aeration device is lower than 0.2 mg / L.

[0029] In some embodiments of the present application, the high dissolved oxygen environment reflow ratio in the sewage treatment tank is 120%-135%; and / or,

[0030] The anaerobic internal circulation reflow ratio is 85%-100%.

[0031] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0032] The device and method for treating heavy oily wastewater provided in the embodiments of the present application use a heavy carrier to form sludge, which is deposited at the bottom of a wastewater treatment tank. The sludge and wastewater are separated by an aeration device, so that the dissolved oxygen content in the sludge is low and the dissolved oxygen content in the wastewater is high. This allows aerobic biochemical reactions and anaerobic biochemical reactions to be carried out simultaneously in the wastewater treatment tank, thereby achieving effective treatment of heavy oily wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0035] Figure 1 A schematic diagram of the structure of a sewage treatment pool provided in an embodiment of the present application;

[0036] Figure 2 A schematic diagram of the distribution of dissolved oxygen content in a sewage treatment pool provided in an embodiment of the present application;

[0037] Figure 3 A schematic structural diagram of a heavy oil wastewater treatment device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0039] Unless otherwise specified, the terms used herein should be understood as commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. In the event of a conflict, this specification takes precedence.

[0040] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0041] The existing treatment of heavy oil wastewater has difficult technical problems.

[0042] The technical solution provided by the embodiments of the present application is to solve the above technical problems, and the overall idea is as follows:

[0043] In the first aspect, the present application embodiment provides a heavy oil wastewater treatment device, please refer to Figure 1 , Figure 3 , the heavy oil wastewater treatment device comprises:

[0044] Sewage treatment tank 1;

[0045] The sludge including the heavy carrier is arranged at the bottom of one side of the sewage treatment tank 1;

[0046] an aeration device 2, arranged above the sludge;

[0047] A flow-pushing device 11 is arranged at the bottom of the sewage treatment tank 1;

[0048] A sewage inlet 12 is arranged at one side of the sewage treatment tank 1 and above the aeration device 2;

[0049] The sewage outlet 13 is arranged at the other side of the sewage treatment tank 1 and above the aeration device 2 .

[0050] The aeration device 2 is a conventional device in the art.

[0051] In the present application, the aeration device 2 includes a blower 21 and a ventilation pipe 22, and the ventilation pipe 22 is provided with an aeration port 222. The ventilation pipe 22 is arranged above the bottom of one side of the sewage treatment tank 1, and the blower 21 connected to the ventilation pipe 22 is arranged outside the sewage treatment tank 1, and the ventilation pipe 22 aerates the sewage treatment tank 1 through the aeration port 222.

[0052] Heavy carriers are conventional materials in the art. Heavy carriers can provide a growth site for microorganisms and adsorb pollutants and microbial metabolites in sewage.

[0053] Sludge is formed in an environment with low dissolved oxygen content through heavy carriers. The sludge itself has poor fluidity and low efficiency in material exchange with the outside world, which easily forms an anaerobic environment.

[0054] Heavy pollutants in sewage have a tendency to settle and form sludge. Heavy carriers can accelerate the formation of sludge, thereby enriching the anaerobic microbial community.

[0055] The reactions that occur in the sludge include but are not limited to the decomposition of long-chain, cyclic, and benzene-like organic pollutants; denitrification reactions. These reactions can increase the biodegradability of sewage.

[0056] As an example, the heavy carrier may be activated carbon. After a large number of microorganisms are generated on the surface of the activated carbon and pollutants and microbial metabolites are adsorbed, the density of the activated carbon will increase and the activated carbon will be deposited at the bottom of the sewage treatment tank 1 to form sludge.

[0057] The presence of the aeration device 2 makes the dissolved oxygen content above the aeration device 2 in the sewage treatment tank 1 significantly higher than that below. This divides the sewage treatment tank 1 into a high dissolved oxygen area and a low dissolved oxygen area. The high dissolved oxygen area is conducive to aerobic biochemical reactions of sewage, and the low dissolved oxygen area is conducive to anaerobic biochemical reactions of sludge.

[0058] The flow pushing device 11 is used to push the sludge from one side of the bottom of the sewage treatment tank 1 to the other side. After the sludge moves to the other side of the sewage treatment tank 1, it is mixed with the sewage after the aerobic biochemical reaction. The mixed sewage is discharged through the sewage outlet 13.

[0059] As the flow-pushing device 11 pushes the sludge, the sludge at the bottom of the sewage treatment tank 1 gradually moves from one side of the sewage treatment tank 1 to the other side. In this process, as the oxygen in the sludge is continuously consumed and the dissolved oxygen content is continuously reduced, the environment in the sludge gradually transitions from an aerobic environment to a facultative environment, and then from a facultative environment to an anaerobic environment. Please refer to Figure 2Based on the dissolved oxygen content, the sludge can be divided into aerobic zone, facultative zone and anaerobic zone from one side to the other side of the sewage treatment tank 1. The top of the aeration device 2 is a high dissolved oxygen zone. Figure 2 The direction indicated by the arrow in the middle is the direction of movement of sludge or sewage. The coexistence of aerobic, facultative and anaerobic environments is conducive to the formation of a comprehensive microbial system and the enhancement of microbial diversity. High dissolved oxygen areas can efficiently decompose organic pollutants and total phosphorus.

[0060] The present application forms sludge by using a heavy carrier, so that the sludge is deposited at the bottom of the sewage treatment tank 1, and the sludge and sewage are separated by an aeration device 2, so that the dissolved oxygen content in the sludge is low and the dissolved oxygen content in the sewage is high. This allows aerobic biochemical reactions and anaerobic biochemical reactions to be carried out simultaneously in the sewage treatment tank 1, thereby achieving effective treatment of heavy oil sewage.

[0061] In addition, the present application realizes a two-phase (sewage phase, sludge phase) three-state (aerobic, facultative, anaerobic) biochemical treatment system in the same structure, which can realize integrated process links, reduce process sequences, and reduce process footprint.

[0062] In some embodiments of this application, please refer to Figure 1 , Figure 3 The heavy oil wastewater treatment device also includes a primary secondary sedimentation tank 3, and the sewage outlet 13 is connected to the primary secondary sedimentation tank 3.

[0063] In some embodiments of the present application, the primary secondary sedimentation tank 3 is connected to a first water purification agent dosing device 31 .

[0064] The first water purifying agent dosing device 31 is used to add water purifying agent to the primary secondary sedimentation tank 3 .

[0065] In some embodiments of the present application, the heavy oil wastewater treatment device also includes a secondary aerobic tank 4 and a secondary secondary sedimentation tank 5 connected to each other, the primary secondary sedimentation tank 3 is connected to the secondary aerobic tank 4, and the secondary secondary sedimentation tank 5 is connected to the sewage inlet 12.

[0066] The sewage discharged from the sewage outlet 13 can be circulated back to the sewage treatment tank 1 after passing through the primary secondary sedimentation tank 3, the secondary aerobic tank 4 and the secondary secondary sedimentation tank 5 in sequence to further deepen the aerobic biochemical reaction.

[0067] In some embodiments of the present application, the primary secondary sedimentation tank 3 is connected to the secondary aerobic tank 4 via a first pumping mechanism 32 .

[0068] The first pumping mechanism 32 can pump the sewage in the primary secondary sedimentation tank 3 to the secondary aerobic tank 4 .

[0069] In some embodiments of the present application, the secondary settling tank 5 is connected to the sewage inlet 12 via a second pumping mechanism 51 .

[0070] The second pumping mechanism 51 can pump the sewage in the secondary settling tank 5 to the sewage inlet 12 .

[0071] In some embodiments of the present application, the secondary settling tank 5 is connected to a second water purification agent dosing device 52 .

[0072] The second water purifying agent dosing device 52 is used to add water purifying agent to the secondary secondary sedimentation tank 5 .

[0073] In some embodiments of the present application, the secondary aerobic tank 4 is connected to a heavy carrier dosing device 41 .

[0074] The heavy carrier dosing device 41 is used to add heavy carriers to the secondary aerobic tank 4. The heavy carrier is added to the secondary aerobic tank 4, can absorb more oxygen, and after being pumped back to the sewage treatment tank 1 by the second pumping mechanism 51, it is quickly deposited to the bottom of one side of the sewage treatment tank 1 to form sludge in the aerobic zone. This is conducive to increasing the dissolved oxygen content in the aerobic zone, so that the dissolved oxygen content can form a gradient distribution mode of aerobic zone, facultative zone, and anaerobic zone.

[0075] In some embodiments of the present application, a ventilation pipe 22 is provided in the secondary aerobic tank 4 , and the ventilation pipe 22 in the sewage treatment tank 1 and the ventilation pipe 22 in the secondary aerobic tank 4 are connected to the same blowing device 21 .

[0076] In some embodiments of the present application, the heavy oil wastewater treatment device further includes a sludge circulation pipe 14 , which is disposed at the bottom of one side of the wastewater treatment tank 1 , and the primary secondary sedimentation tank 3 is connected to the sludge circulation pipe 14 .

[0077] The sewage discharged from the sewage outlet 13 can be circulated back to the sewage treatment tank 1 after passing through the primary secondary sedimentation tank 3 to further deepen the anaerobic biochemical reaction.

[0078] In some embodiments of the present application, the primary secondary sedimentation tank 3 is connected to the sludge circulation pipe 14 via a third pumping mechanism 33 .

[0079] The third pumping mechanism 33 can pump the sewage in the primary secondary sedimentation tank 3 to the sludge circulation pipe 14 .

[0080] In a second aspect, an embodiment of the present application provides a method for treating heavy oily wastewater, wherein the method for treating heavy oily wastewater is implemented by the heavy oily wastewater treatment device according to the first aspect, and the method for treating heavy oily wastewater comprises the following steps:

[0081] S1: introducing sewage from the sewage inlet 12 into the sewage treatment tank 1, adding a heavy carrier into the sewage treatment tank 1, and forming sludge from the heavy carrier;

[0082] S2: operating the aeration device 2 to increase the oxygen content of the sewage above the aeration device 2, so that the sewage above the aeration device 2 undergoes an aerobic biochemical reaction;

[0083] S3: allowing the sludge below the ventilation device to undergo anaerobic biochemical reaction;

[0084] S4: The sludge at the bottom of the sewage treatment tank 1 is pushed to the upper part of the sewage treatment device by the flow pushing device 11, and is mixed with the sewage that has undergone aerobic biochemical reaction to form primary treated sewage, which is then discharged through the sewage outlet 13.

[0085] In some embodiments of the present application, the primary treated sewage enters the primary secondary sedimentation tank 3 through the sewage outlet 13, then enters the secondary aerobic tank 4 for aerobic biochemical reaction, then enters the secondary secondary sedimentation tank 5, and circulates back to the sewage treatment tank 1 through the sewage inlet 12.

[0086] In some embodiments of the present application, the primary treated sewage enters the primary secondary sedimentation tank 3 through the sewage outlet 13 and then circulates back to the sewage treatment tank 1 through the sludge circulation pipe 14 .

[0087] In some embodiments of the present application, when the sewage is treated in the sewage treatment tank 1,

[0088] The hydraulic retention time is 13-15h; and / or,

[0089] COD load is 10.8-16.8kg / (m 3 d); and / or,

[0090] The liquid phase pH is 7.0-7.5; and / or,

[0091] The water temperature is 25-30°C; and / or,

[0092] The suspended sludge concentration is 11000-13000 mg / L.

[0093] In some embodiments of the present application, the dissolved oxygen concentration of the sewage above the aeration device 2 is 6-8 mg / L; and / or,

[0094] The dissolved oxygen concentration in the anaerobic environment below the aeration device 2 is lower than 0.2 mg / L.

[0095] In some embodiments of the present application, the high dissolved oxygen environment reflow ratio in the sewage treatment pool 1 is 120%-135%; and / or,

[0096] The anaerobic internal circulation reflow ratio is 85%-100%.

[0097] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0098] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the present application specification, the terms "including", "comprising", etc. refer to "including but not limited to". Moreover, the terms "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the sentence "including..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. For the association relationship of more than three associated objects described by "and / or", it means that any one of these three associated objects can exist alone, or any at least two of them exist at the same time. For example, for A, and / or B, and / or C, it can be represented that any one of A, B, and C exists alone, or any two of them exist at the same time, or three of them exist at the same time. In this article, "at least one" refers to one or more, and "multiple" refers to two or more. "At least one", "the following at least one (individual)" or similar expressions refer to any combination of these items, including any combination of single (individual) or plural (individual). For example, "at least one (individual) of a, b, or c", or "at least one (individual) of a, b, and c", can all represent: a, b, c, ab (i.e. a and b), ac, bc, or abc, wherein a, b, and c can be single or multiple, respectively.

[0099] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A heavy oil wastewater treatment device, characterized in that: The heavy oil wastewater treatment device comprises: sewage treatment tanks; The sludge including the heavy carrier is arranged at the bottom of one side of the sewage treatment tank; an aeration device, arranged above the sludge; A flow-pushing device is arranged at the bottom of the sewage treatment tank; A sewage inlet is arranged on one side of the sewage treatment tank and above the aeration device; The sewage outlet is arranged at the other side of the sewage treatment tank and above the aeration device.

2. The heavy oil wastewater treatment device according to claim 1, characterized in that: The heavy oil wastewater treatment device also includes a primary secondary sedimentation tank, and the sewage outlet is connected to the primary secondary sedimentation tank.

3. The heavy oil wastewater treatment device according to claim 2 is characterized in that: The heavy oil wastewater treatment device further comprises a secondary aerobic tank and a secondary secondary sedimentation tank which are connected to each other. The primary secondary sedimentation tank is connected to the secondary aerobic tank, and the secondary secondary sedimentation tank is connected to the sewage inlet.

4. The heavy oil wastewater treatment device according to claim 2, characterized in that: The thick oil wastewater treatment device also includes a sludge circulation pipe, which is arranged at the bottom of one side of the wastewater treatment tank, and the primary secondary sedimentation tank is connected to the sludge circulation pipe.

5. A method for treating heavy oil wastewater, characterized in that: The method for treating heavy oily wastewater is implemented by the heavy oily wastewater treatment device according to any one of claims 1 to 4, and the method for treating heavy oily wastewater comprises the following steps: Introducing sewage from the sewage inlet into the sewage treatment tank, adding a heavy carrier into the sewage treatment tank, and forming sludge from the heavy carrier; Running the aeration device to increase the oxygen content of the sewage above the aeration device so that the sewage above the aeration device undergoes an aerobic biochemical reaction; Allowing the sludge below the ventilation device to undergo anaerobic biochemical reaction; The sludge at the bottom of the sewage treatment tank is pushed to the upper part of the sewage treatment device by the flow pushing device, mixed with the sewage after aerobic biochemical reaction to form primary treated sewage, and discharged through the sewage outlet.

6. The method for treating heavy oily wastewater according to claim 5, characterized in that: The primary treated sewage enters the primary secondary sedimentation tank through the sewage outlet, enters the secondary aerobic tank for aerobic biochemical reaction, then enters the secondary secondary sedimentation tank, and circulates back to the sewage treatment tank through the sewage inlet.

7. The method for treating heavy oily wastewater according to claim 5, characterized in that: After the primary treated sewage enters the primary secondary sedimentation tank through the sewage outlet, it circulates back to the sewage treatment tank through the sludge circulation pipe.

8. The method for treating heavy oily wastewater according to claim 5, characterized in that: When the sewage is treated in the sewage treatment tank, The hydraulic retention time is 13-15h; and / or, COD load is 10.8-16.8kg / (m 3 d); and / or, The liquid phase pH is 7.0-7.5; and / or, The water temperature is 25-30°C; and / or, The suspended sludge concentration is 11000-13000 mg / L.

9. The method for treating heavy oily wastewater according to claim 5, characterized in that: The dissolved oxygen concentration of the sewage above the aeration device is 6-8 mg / L; and / or, The dissolved oxygen concentration in the anaerobic environment below the aeration device is lower than 0.2 mg / L.

10. The method for treating heavy oil wastewater according to claim 5, characterized in that: The high dissolved oxygen environment reflow ratio in the sewage treatment tank is 120%-135%; and / or, The anaerobic internal circulation reflow ratio is 85%-100%.

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