Water mixing device for heavy oil discharge sewage

Abstract

The invention discloses a heavy oil discharge sewage water quality mixing device, and relates to the technical field of oil field produced water discharge. The top of the inner barrel is of an opening structure, and the inner barrel is used for mixing and adsorbing effluent and raw water; the outer barrel is used for outputting the mixed water; the first conveying pipeline is connected with the inner barrel and is used for conveying the adsorbed effluent to the inner barrel; the second transportation pipeline is connected with the inner cylinder body and is used for transporting the raw water to the inner cylinder body; the baffles are uniformly arranged on the side wall of the inner cylinder body and are used for enabling the adsorbed effluent and the raw water to form rotational flow; the stirrer is used for disturbing the adsorbed effluent and the raw water in the barrel; and the cover plate is arranged at the top of the outer cylinder. After the device is used for mixing water, the COD (Chemical Oxygen Demand) of the effluent is controlled between 40 and 50mg / L, which is close to the standard requirement. The adsorption performance of the activated carbon is fully utilized, so that the service life of the activated carbon is prolonged, the regeneration period is prolonged by 75%, and the sewage treatment cost of the activated carbon is reduced by 42.9%.

Description

Technical Field

[0001] The present invention relates to the technical field of external discharge of produced water in oilfields, and particularly relates to a device for mixing treated high-quality water and low-quality raw water. Background Art

[0002] In the thermal recovery development blocks of Liaohe Oilfield, there are generally situations of injection-production imbalance and excessive produced water, and there is an urgent need to develop sewage external discharge technology. After multiple technical demonstrations and on-site experiments, the "PACT" process of Siemens Company was finally adopted, and the up-to-standard external discharge of super heavy oil sewage was realized for the first time in China. However, its treatment cost is relatively high. To ensure the benefits of enterprises, it is necessary to continue to research and develop low-cost sewage external discharge technology.

[0003] Therefore, on the basis of fully learning from the experience and lessons of the "PACT" process, the process of "A / O biochemical + granular carbon adsorption" was independently developed and successfully applied to the external discharge project of common heavy oil in Xiaowa Oilfield. Compared with the "PACT" process, the same treatment process of biochemical + activated carbon adsorption is adopted, which not only retains the advantages of low biochemical treatment cost, good activated carbon adsorption performance, high COD removal rate, and stable effluent quality; at the same time, the A / O biochemical process is used to replace the simple aerobic biochemical process, so that long-chain organic matter is hydrolyzed and broken chain under anaerobic conditions, improving the B / C ratio of sewage, increasing biodegradability, and improving the efficiency of the biochemical process. Through actual engineering verification, the COD removal rate of the A / O biochemical process is nearly doubled compared with the simple aerobic process, increasing from 25-30% to 50-55%; at the same time, the fixed filling of activated carbon is used to replace manual dosing, keeping the amount of activated carbon used constant, avoiding the uncertainty of manual carbon dosing, and being able to effectively control the treatment cost, achieving the purpose of reducing the sewage treatment cost.

[0004] As Figure 1 shown, according to the adsorption breakthrough curve of activated carbon and the actual engineering situation, in the initial stage of using fresh or regenerated granular carbon, its adsorption capacity is the largest and the adsorption effect is the strongest. When the influent COD concentration is C 0 , the effluent COD concentration is below C a , and C a is much smaller than C 0 . According to the actual situation of the engineering site, the influent COD is about 100mg / L, and the effluent COD concentration in the initial stage of activated carbon operation is 10-20mg / L, and the removal rate is as high as over 80%. As the use time increases, the adsorption capacity of activated carbon gradually decreases, the effluent COD gradually increases, and it shows a linear growth relationship with the operation time of activated carbon. When reaching point a in the figure, that is, after the effluent COD concentration reaches C a , the effluent COD shows a sharp upward trend and reaches point b in a short time. At this time, the effluent COD concentration C b is the same as the influent COD concentration C 0The difference is not big, and with the increase of usage time, its concentration does not change and remains C b Point a in the curve is defined as the breakthrough point, indicating that the adsorption performance of activated carbon will drop sharply after reaching this point; point b is defined as the saturation point, indicating that the activated carbon has completely lost its usability after reaching this point and needs to be regenerated.

[0005] According to the above-mentioned activated carbon characteristics, considering that in the "A / O biochemical + granular carbon adsorption" process, the activated carbon is fixedly loaded in the treatment container, that is, the amount of activated carbon used is fixed. Therefore, there must be excellent treatment effects in the initial use, and the effluent water quality is much better than the discharge standard requirements (Liaoning Province requires COD≤50mg / L), but due to process limitations, the purpose of adjusting water quality cannot be achieved by adjusting the amount of activated carbon used, resulting in a waste of adsorption capacity and an increase in unnecessary sewage treatment costs.

[0006] Therefore, it is urgent to study a water quality mixing device, which can flexibly adjust the amount of water treated by activated carbon according to the usage time of activated carbon under the premise of fixed activated carbon usage, and then evenly mix the treated sewage with the raw water so that the COD of the mixed sewage just meets the emission standard requirements (40-50mg / L), so as to fully utilize the adsorption capacity of activated carbon, prolong the saturation time of activated carbon, and reduce the cost of sewage treatment. Summary of the invention

[0007] The present invention provides a water quality mixing device for heavy oil discharged sewage, which can maximize the use of the adsorption capacity of activated carbon, reduce the frequency of activated carbon regeneration as much as possible, and effectively control the sewage treatment cost.

[0008] To achieve the above purpose, the technical solution of the present application is: a heavy oil wastewater mixing device, comprising:

[0009] The inner cylinder has an open top for mixing the adsorbed water and the raw water;

[0010] An outer cylinder, used for outputting mixed water;

[0011] A first transport pipeline is connected to the inner cylinder and is used to transport the adsorbed water to the inner cylinder;

[0012] A second transport pipeline is connected to the inner cylinder and is used to transport raw water to the inner cylinder;

[0013] Baffles are evenly arranged on the side wall of the inner cylinder to form a swirling flow of the adsorbed water and the raw water;

[0014] Agitator, which disturbs the adsorbed water and raw water in the cylinder;

[0015] The cover plate is arranged on the top of the outer cylinder.

[0016] Further, regulating valves and flow meters are provided on both the first transport pipeline and the second transport pipeline.

[0017] Further, an overflow pipe is provided between the inner cylinder and the outer cylinder, and the top end of the overflow pipe is higher than the top end of the inner cylinder.

[0018] Further, a water outlet is provided at the lower part or the bottom of the outer cylinder, and the water outlet is connected to a drainage pipeline.

[0019] Further, regulating valves and an on-line COD detector are provided on the drainage pipeline.

[0020] Even further, the mixed water of the adsorbed effluent and the raw water overflows from the top of the inner cylinder into the outer cylinder.

[0021] Even further, the inner cylinder and the outer cylinder are concentrically arranged, and the height of the inner cylinder is lower than the height of the outer cylinder.

[0022] Even further, the stirrer is a top-mounted paddle stirrer, which is fixed on the cover plate.

[0023] Even further, the baffle is connected to the inner wall of the inner cylinder by bolts.

[0024] Even further, a manhole and a ventilation hole are provided on the cover plate.

[0025] Due to the adoption of the above technical solutions, the present invention can achieve the following technical effects: Before the device is used, the COD of the discharged sewage is between 10 - 20 mg / L, far better than the standard requirements. After the water quality is mixed using this device, the COD of the effluent is controlled between 40 - 50 mg / L, approaching the standard requirements. Since the adsorption performance of the activated carbon is fully utilized, the service life of the activated carbon is extended, the regeneration period is extended by 75%, and the cost of treating sewage with activated carbon is reduced by 42.9%. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the adsorption breakthrough curve graph of activated carbon in the prior art;

[0027] Figure 2 is the top view of the heavy oil discharged sewage water quality mixing device;

[0028] Figure 3 is the side view of the heavy oil discharged sewage water quality mixing device;

[0029] Explanation of the numbers in the figure: 1 - regulating valve; 2 - flow meter; 3 - stirrer; 4 - manhole; 5 - baffle; 6 - on-line COD detector. DETAILED DESCRIPTION OF THE INVENTION

[0030] The principles of the present disclosure will be described below with reference to several exemplary embodiments shown in the accompanying drawings. Although the preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the description of these embodiments is only for enabling those skilled in the art to better understand and then implement the present disclosure, rather than limiting the scope of the present disclosure in any way.

[0031] The principles of the present disclosure will be described below with reference to several exemplary embodiments shown in the accompanying drawings. Although the preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the description of these embodiments is only for enabling those skilled in the art to better understand and then implement the present disclosure, rather than limiting the scope of the present disclosure in any way.

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the specification of the embodiments of the present application. Obviously, the described embodiments are some, rather than all, of the embodiments of the present application. Generally, the components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0034] It should be noted that like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0035] It should be noted that in this document, the term "comprising", "including" or any other variation thereof is intended to cover a non-exclusive inclusion, such that an article or device including a series of elements includes not only those elements but also other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device including the element.

[0036] In the description of the present application, the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is customarily placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0037] In the description of the present application, it should also be noted that unless otherwise clearly specified and defined, the terms "set" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. Terms such as "first", "second", etc. can refer to different or the same objects. There may also be other explicit and implicit definitions below.

[0038] This embodiment provides a heavy oil discharged sewage water quality mixing device to solve the waste phenomenon that the treated water quality is too good due to the good adsorption performance of activated carbon in the initial stage of use. On the premise of a fixed amount of activated carbon used, according to the use time of the activated carbon, the treated water volume is flexibly regulated, and the treated sewage is evenly mixed with the remaining raw water so that the water quality of the mixed water just meets the standard requirements. It includes an inner cylinder and an outer cylinder, and the inner cylinder and the outer cylinder are concentrically arranged, and the height of the inner cylinder is lower than the height of the outer cylinder. Among them:

[0039] The inner cylinder has an open top structure and is used for mixing the adsorbed effluent and the raw water;

[0040] The outer cylinder is used for outputting the mixed water;

[0041] The first transport pipeline is connected to the inner cylinder and is used for transporting the adsorbed effluent to the inner cylinder. A regulating valve and a flow meter are provided on this pipeline;

[0042] The second transport pipeline is connected to the inner cylinder and is used for transporting the raw water to the inner cylinder. A regulating valve and a flow meter are provided on this pipeline;

[0043] The baffle plates are evenly arranged on the side wall of the inner cylinder and are used for forming a swirling flow of the adsorbed effluent and the raw water;

[0044] The stirrer disturbs the adsorbed effluent and the raw water in the cylinder;

[0045] The cover plate is arranged on the top of the outer cylinder.

[0046] The external shape of the above-mentioned heavy oil discharged sewage quality mixing device can be processed into a cylindrical shape or a columnar shape according to the actual situation. The top of its outer cylinder body is provided with a cover plate, and a manhole and a ventilation hole are reserved on the cover plate. The inner cylinder body is a mixing chamber, and the top is not capped. In order to ensure the mixing effect, it is preferred that the inner cylinder body is cylindrical to avoid the formation of dead water areas and short circuits. The effective volume of the mixing chamber should ensure that the mixing time is between 10 and 60 seconds; 4 baffles are evenly arranged in the cylinder, and the baffles have a detachable function and are bolted to the inner wall of the mixing chamber; a top-mounted paddle stirrer is arranged in the center of the mixing chamber, and the top-mounted paddle stirrer is fixedly installed on the cover plate. The rotation speed and power of the stirrer should ensure that the mixing velocity gradient is between 600 and 1000 s -1 -1. The outer cylinder body is an outlet chamber, and its effective volume should ensure that the buffering time is more than 30 seconds. An outlet is arranged at the lower side or bottom of the outer cylinder body for discharging the mixed water.

[0047] The working principle of the above-mentioned heavy oil discharged sewage quality mixing device is that the adsorbed effluent and the raw water enter the mixing chamber inside the device in two ways. The purpose of adjusting the water inflow is achieved by adjusting the opening degree of the valve, and the flow rates of the two-way influent water are obtained through a flow meter so as to accurately adjust the water volume in real time according to the water quality; after the two waters with different water qualities enter the mixing chamber, under the action of the stirrer and the baffle, the water in the inner cylinder body forms a swirling flow with intense disturbance, which is conducive to the mixing and transfer of substances in the sewage. The two sewage waters are evenly mixed here, ensuring the stability of the effluent water quality. The water in the inner cylinder body overflows from the top into the outer cylinder body and enters the next process through the drainage pipeline of the outer cylinder body. A COD on-line detector is arranged on the drainage pipeline to automatically monitor the effluent COD in real time on-line to ensure that the mixed water quality is controlled within the requirements of the discharge standard. Once an abnormality occurs, the effluent water quality is adjusted by adjusting the flow rates of the two-way influent water. An overflow pipe is also arranged in the outer cylinder body. When the water level in the outer cylinder body is too high, the excess water is discharged from the overflow pipe and recycled for re-treatment to avoid the occurrence of tank overflow accidents.

[0048] The above device is used in the project of discharging ordinary heavy oil sewage in Xiaowa Oilfield. The adsorbed tower effluent (COD between 10 and 20 mg / L) and the raw water (COD about 90 mg / L) are mixed in a certain proportion so that the effluent COD after mixing is between 40 and 50 mg / L, approaching the requirements of the sewage discharge standard in Liaoning Province, and then flows to the discharge point and is discharged into the natural water body.

[0049] Since the device was put into operation, the regeneration cycle of activated carbon in Wa-1 has been extended by 75%, and the cost of treating sewage with activated carbon has been reduced by 42.9%.

[0050] Table 1 Water volume ratio table under different water qualities

[0051]

[0052] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. For those skilled in the art, the present disclosure can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.

[0053] Although the claims in this application have been formulated for specific combinations of features, it should be understood that the scope of the present disclosure also includes any novel feature or any novel combination of features that are explicit or implicit or any generalization thereof disclosed herein, whether or not it relates to the same solution in any of the currently claimed claims.

Claims

1. A device for mixing the quality of produced sewage from heavy oil external discharge, characterized in that, it includes: An inner cylinder body, the top of which is an open structure for mixing and adsorbing effluent and raw water; An outer cylinder body for outputting mixed water; A first transportation pipeline connected to the inner cylinder body for transporting the adsorbed effluent to the inner cylinder body; A second transportation pipeline connected to the inner cylinder body for transporting raw water to the inner cylinder body; Baffles evenly arranged on the side wall of the inner cylinder body for forming a swirl of the adsorbed effluent and raw water; A stirrer for disturbing the adsorbed effluent and raw water in the cylinder body; A cover plate arranged on the top of the outer cylinder body.

2. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, Regulating valves and flow meters are provided on both the first transportation pipeline and the second transportation pipeline.

3. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, An overflow pipe is provided between the inner cylinder body and the outer cylinder body, and the top end of the overflow pipe is higher than the top end of the inner cylinder body.

4. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, A water outlet is arranged at the lower part or bottom of the outer cylinder body, and the water outlet is connected to a drainage pipeline.

5. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 4, characterized in that, Regulating valves and an on-line COD detector are provided on the drainage pipeline.

6. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, The mixed water of the adsorbed effluent and raw water overflows from the top of the inner cylinder body into the outer cylinder body.

7. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, The inner cylinder body and the outer cylinder body are concentrically arranged, and the height of the inner cylinder body is lower than the height of the outer cylinder body.

8. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, The stirrer is a top-mounted paddle stirrer, which is fixed on the cover plate.

9. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, The baffle is connected to the inner wall of the inner cylinder body by bolts.

10. The device for mixing the quality of produced sewage from heavy oil external discharge according to claim 1, characterized in that, Manholes and ventilation holes are provided on the cover plate.

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