Oily wastewater treatment device in MTO (methanol to olefin) process

Abstract

The utility model provides an oily wastewater treatment device in an MTO (Methanol To Olefins) process, and solves the technical problem that a sewage treatment device has a poor separation effect on oil in water. The device comprises a first-stage separator, a second-stage separator and a third-stage separator which are sequentially connected through a pipeline, and the first-stage separator is filled with mechanical filler and is used for filtering a solid phase; a water outlet of the first-stage separator is communicated with a water inlet of the second-stage separator through a pipeline, and an oleophylic and hydrophobic part is arranged in the second-stage separator and is used for capturing oil drops; a water outlet of the second-stage separator is communicated with a water inlet of the third-stage separator through a pipeline, a filter element is arranged in the third-stage separator, and the filter element is filled with an oleophylic and hydrophobic material and is used for further separating oil from water; the second-stage separator and the third-stage separator are respectively provided with an oil outlet, and the oil outlets are communicated with an oil tank; oil can be well separated from water through the triple separator, the separated oil enters the oil tank to be treated, and the treated water can be recycled.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical equipment, in particular to an oily wastewater treatment device in an MTO process. Background Art

[0002] The MTO process is a chemical process technology that uses methanol as raw material and uses a fluidized bed reaction in a catalytic cracking unit to produce low-carbon olefins (ethylene, propylene). The main process is that methanol is first dehydrated to dimethyl ether (DME), and the resulting equilibrium mixture includes methanol, dimethyl ether and water, and then converted into low-carbon olefins. The low-carbon olefins are converted into alkanes, aromatics, cycloalkanes and higher-level olefins through hydrogen transfer, alkylation and polycondensation reactions. Methanol is dehydrated to dimethyl ether under the action of a solid acid catalyst, and the intermediate is a protonated surface methoxy group; low-carbon olefins are converted into alkanes, aromatics, cycloalkanes and higher-level olefins. Various by-products will be produced in this process, such as dimethyl ether, propionaldehyde, acetone, oxygen-containing compounds, etc. Among them, aldehydes and ketones will undergo condensation reactions under high temperature conditions to form oil substances dispersed in water.

[0003] The water in the MTO process contains the above substances and can only be treated as wastewater and cannot be recycled in the process system. Therefore, the oil substances need to be removed and the treated water can be recycled.

[0004] The applicant has found that the prior art has at least the following technical problems: the treatment device in the prior art has a poor removal effect on oil substances, which affects the recycling of water quality. Utility Model Content

[0005] The purpose of the utility model is to provide an oily wastewater treatment device in the MTO process to solve the technical problem that the wastewater treatment device in the prior art has a poor separation effect on oil in water; the many technical effects that can be produced by the preferred technical solution among the many technical solutions provided by the utility model are described in detail below.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] The oily wastewater treatment device in the MTO process provided by the utility model comprises a primary separator, a secondary separator and a tertiary separator which are sequentially connected by pipelines, wherein:

[0008] The first-stage separator is filled with mechanical fillers for filtering the solid phase;

[0009] The water outlet of the primary separator is connected to the water inlet of the secondary separator through a pipeline, and an oleophilic and hydrophobic part is provided in the secondary separator, and the oleophilic and hydrophobic part is used to capture oil droplets;

[0010] The water outlet of the secondary separator is connected to the water inlet of the tertiary separator through a pipeline. The tertiary separator is provided with a filter element filled with oleophilic and hydrophobic materials for further separating oil from water.

[0011] The secondary separator and the tertiary separator are both provided with an oil outlet, and the oil outlet is connected to an oil tank.

[0012] Preferably, at least two mounting plates are fixed on the inner wall of the primary separator, and adjacent mounting plates are spaced apart along the length direction of the primary separator. The mechanical filler is loaded between two adjacent mounting plates, and liquid can flow through the mounting plates.

[0013] Preferably, the mounting plate is provided with mesh holes for fluid to pass through.

[0014] Preferably, the number of the secondary separators is two, and the two secondary separators are interconnected and allow the oily wastewater to pass through in sequence.

[0015] Preferably, a containing chamber is provided in the secondary separator, a liquid inlet is provided at the bottom of the containing chamber, a liquid outlet is provided at the top of the containing chamber, and the liquid inlet and the liquid outlet are respectively connected to the water inlet and the water outlet of the secondary separator;

[0016] The oleophilic and hydrophobic part is an oleophilic and hydrophobic filler and is filled in the containing cavity.

[0017] Preferably, the filter element is arranged vertically.

[0018] Preferably, the number of the filter elements is 20-80, and all the filter elements are arranged in parallel.

[0019] Preferably, a supporting mesh plate is fixed inside the three-stage separator, and the bottoms of all the filter elements are fixed on the same supporting mesh plate.

[0020] Preferably, a pump body is provided between the primary separator and the secondary separator.

[0021] Compared with the prior art, the oil-containing wastewater treatment device in the MTO process provided by the utility model has the following beneficial effects: the wastewater to be treated passes through the primary separator, and the solid phase can be filtered by mechanical filler to prolong the residence time of the heavy oil; the oil-containing wastewater after preliminary treatment enters the secondary separator, and the oil droplets are captured by the oleophilic and hydrophobic part in the secondary separator to further separate the oil; the water containing a small amount of oil enters the tertiary separator, and the filter element therein is used to further separate the oil from the water; after passing through the triple separator, the oil can be better separated from the water, so that the separated oil enters the oil tank to be treated, and the treated water can be recycled. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the utility model 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, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a schematic diagram of the overall structure of the oily wastewater treatment device in the MTO process;

[0024] Figure 2 It is a schematic diagram of the structure of the installation disk.

[0025] In the figure, 1, primary separator; 11, mounting plate; 12, mechanical filler; 2, secondary separator; 21, accommodating chamber; 22, liquid inlet; 23, liquid outlet; 3, pump body; 4, tertiary separator; 41, filter element; 42, supporting mesh plate; 5, oil tank. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the utility model.

[0027] In the description of the present invention, it should be understood that the terms "center", "length", "width", "height", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "side" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention 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 cannot be understood as a limitation on the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0028] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The embodiment of the utility model provides an oily wastewater treatment device in the MTO process, which can separate oil from water well, so that the separated oil enters the oil tank for treatment, and the treated water can be recycled.

[0030] Combine the following Figure 1 and Figure 2 The technical solution provided by the utility model is described in more detail.

[0031] like Figure 1 As shown, the oily wastewater treatment device in the MTO process provided by the utility model comprises a primary separator 1, a secondary separator 2 and a tertiary separator 4 which are sequentially connected by pipelines, wherein: the primary separator 1 is filled with a mechanical filler 12 for filtering the solid phase; the water outlet of the primary separator 1 is communicated with the water inlet of the secondary separator 2 through a pipeline, and an oleophilic and hydrophobic portion is provided in the secondary separator 2, which is used to capture oil droplets; the water outlet of the secondary separator 2 is communicated with the water inlet of the tertiary separator 4 through a pipeline, and a filter element 41 is provided in the tertiary separator 4, and the filter element 41 is filled with an oleophilic and hydrophobic material for further separating oil from water; the secondary separator 2 and the tertiary separator 4 are both provided with oil outlets, and the oil outlets are connected with an oil tank 5.

[0032] Specifically, the wastewater to be treated is connected to the water inlet of the primary separator 1 through a pipeline.

[0033] In the oily wastewater treatment device in the MTO process of this embodiment, the wastewater to be treated passes through the primary separator 1, and the mechanical filler 12 can be used to filter the solid phase to extend the residence time of the heavy oil. The oily wastewater after preliminary treatment enters the secondary separator 2, and the oil droplets are captured by the oleophilic and hydrophobic part in the secondary separator 2 to further separate the oil. The water containing a small amount of oil enters the tertiary separator 4, and the filter element 41 therein is used to further separate the oil from the water. After passing through the triple separator, the oil can be better separated from the water, so that the separated oil enters the oil tank 5 to be treated, and the treated water can be recycled.

[0034] Among them, the above-mentioned mechanical filler 12 mainly includes one or more of ball rings, Raschig rings, step rings, arc saddle fillers, rectangular saddle fillers, metal ring rectangular saddle fillers, and spherical fillers. The filling method is random stacking, occupying 20-60% of the equipment space, and the filler is fixed by two mounting plates 11 with a diameter of 118 cm.

[0035] The lipophilic and hydrophobic parts in the secondary separator 2 and the lipophilic and hydrophobic materials in the filter element 41 mainly include one or more block fillers selected from polytetrafluoroethylene, polyvinylidene fluoride, polypropylene, polyethylene, polyester, polycarbonate, and fluorosilicone resin.

[0036] As an alternative embodiment, see Figure 1 and Figure 2 As shown, at least two mounting plates 11 are fixed on the inner wall of the primary separator 1 , and adjacent mounting plates 11 are spaced apart along the length direction of the primary separator 1 . A mechanical filler 12 is loaded between two adjacent mounting plates 11 , and liquid can flow through the mounting plates 11 .

[0037] The filling position and volume of the mechanical filler 12 are limited by two mounting plates 11, see Figure 2 As shown, the mounting plate 11 is provided with mesh holes, through which oily wastewater can pass.

[0038] The main functions of the mechanical filler 12 are to increase the transport path of the liquid and to separate the oil, water and solid phases.

[0039] As an alternative embodiment, see Figure 1 As shown, there are two secondary separators 2, and the two secondary separators 2 are connected and allow the oily wastewater to pass through in sequence.

[0040] In the above structure, the wastewater to be treated passes through two secondary separators 2 in sequence, which can improve the separation effect of oil and water.

[0041] As an alternative embodiment, see Figure 1 As shown, a accommodating chamber 21 is provided in the secondary separator 2, a liquid inlet 22 is provided at the bottom of the accommodating chamber 21, and a liquid outlet 23 is provided at the upper part of the accommodating chamber 21. The liquid inlet 22 and the liquid outlet 23 are respectively connected with the water inlet and the water outlet of the secondary separator 2; the oleophilic and hydrophobic part is an oleophilic and hydrophobic filler, and is filled in the accommodating chamber 21.

[0042] The above structure is convenient for filling the oleophilic and hydrophobic parts. The oleophilic and hydrophobic fillers mainly include one or more block fillers selected from polytetrafluoroethylene, polyvinylidene fluoride, polypropylene, polyethylene, polyester, polycarbonate, and fluorosilicone resin.

[0043] As an optional embodiment, the filter cores 41 are arranged vertically. The number of filter cores 41 is 20-80, and all filter cores 41 are arranged in parallel.

[0044] The above structure can improve the treatment effect of oily wastewater and improve the treatment efficiency.

[0045] As an alternative embodiment, see Figure 1 As shown, a supporting mesh plate 42 is fixed inside the three-stage separator 4 , and the bottoms of all filter elements 41 are fixed on the same supporting mesh plate 42 .

[0046] The above structure facilitates fixing the filter element 41, and all the filter elements 41 are fixed to the same supporting mesh plate 42, which can increase the sewage treatment volume per unit time and improve the treatment efficiency.

[0047] As an alternative embodiment, see Figure 1 As shown, a pump body 3 is arranged between the primary separator 1 and the secondary separator 2 .

[0048] After the primary separator 1 separates the solid phase, the flow rate decreases, and the pump body 3 makes the oily wastewater flowing out of the primary separator 1 have a certain pressure, which facilitates the oily wastewater to continue to pass through the secondary separator 2 and the tertiary separator 4.

[0049] In this embodiment, the lipophilic and hydrophobic materials in the secondary separator 2 and the tertiary separator 4 adopt different structural forms: the lipophilic and hydrophobic materials in the secondary separator 2 are filled in the accommodating cavity 21, and the lipophilic and hydrophobic materials in the tertiary separator 4 separate the oil from the water in the form of a filter element 41. The above different forms are connected in series to improve the separation effect.

[0050] In the description of this specification, specific features, structures or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0051] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0052] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. An oily wastewater treatment device in an MTO process, characterized in that: It includes a primary separator, a secondary separator and a tertiary separator connected in sequence through pipelines, wherein: The first-stage separator is filled with mechanical fillers for filtering the solid phase; The water outlet of the primary separator is connected to the water inlet of the secondary separator through a pipeline, and an oleophilic and hydrophobic part is provided in the secondary separator, and the oleophilic and hydrophobic part is used to capture oil droplets; The water outlet of the secondary separator is connected to the water inlet of the tertiary separator through a pipeline. The tertiary separator is provided with a filter element filled with oleophilic and hydrophobic materials for further separating oil from water. The secondary separator and the tertiary separator are both provided with an oil outlet, and the oil outlet is connected to an oil tank.

2. The oily wastewater treatment device in the MTO process according to claim 1 is characterized in that: At least two mounting plates are fixed on the inner wall of the primary separator, and adjacent mounting plates are arranged at intervals along the length direction of the primary separator. The mechanical filler is loaded between two adjacent mounting plates, and liquid can flow through the mounting plates.

3. The oily wastewater treatment device in the MTO process according to claim 2 is characterized in that: The installation plate is provided with mesh holes for fluid to pass through.

4. The oily wastewater treatment device in the MTO process according to claim 1, characterized in that: The number of the secondary separators is two, and the two secondary separators are connected and allow the oily wastewater to pass through in sequence.

5. The oily wastewater treatment device in the MTO process according to claim 1, characterized in that: The secondary separator is provided with a receiving chamber, the bottom of the receiving chamber is provided with a liquid inlet, the upper part of the receiving chamber is provided with a liquid outlet, the liquid inlet and the liquid outlet are respectively connected with the water inlet and the water outlet of the secondary separator; The oleophilic and hydrophobic part is an oleophilic and hydrophobic filler and is filled in the containing cavity.

6. The oily wastewater treatment device in the MTO process according to claim 1, characterized in that: The filter element is arranged vertically.

7. The oily wastewater treatment device in the MTO process according to claim 1, characterized in that: The number of the filter elements is 20-80, and all the filter elements are arranged in parallel.

8. The oily wastewater treatment device in the MTO process according to claim 1, characterized in that: A supporting mesh plate is fixed inside the three-stage separator, and the bottoms of all the filter elements are fixed on the same supporting mesh plate.

9. The oily wastewater treatment device in the MTO process according to claim 1, characterized in that: A pump body is arranged between the primary separator and the secondary separator.

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