Steam stripping dephenolization system

Abstract

The utility model belongs to the technical field of industrial wastewater treatment, and particularly relates to a steam stripping dephenolization system, which comprises a steam stripping section positioned at the upper section of a closed tower, and a plurality of water collecting tanks arranged below the steam stripping section; the regeneration section is positioned at the lower section of the closed tower, and a steam channel is arranged below the regeneration section; the spraying system comprises a spraying assembly I, a spraying assembly II and a spraying assembly III; the spraying assembly I is positioned above the steam stripping section and is connected with the preheater through a pipeline; the spraying assembly II is positioned above the regeneration section; and the spraying assembly III is positioned in the filler layer of the regeneration section.

Description

TECHNICAL FIELD

[0001] The utility model belongs to industrial wastewater treatment technical field, concretely relates to a stripping phenol removal system. BACKGROUND

[0002] The removal object of stripping method is volatile dissolved matter, which is through the direct contact of waste water and steam, so that the volatile matter in waste water diffuses into gas phase according to certain proportion, thereby separating the volatile pollutants from waste water. Stripping phenol removal is mainly aimed at volatile phenolic substances, which makes phenols into steam through the heating and stripping effect of steam, and then recovers phenols through alkali absorption and other means.

[0003] Traditional stripping method needs to run under medium temperature and medium pressure conditions (such as 38 DEG C, 0.68 MPa), and the requirement for equipment pressure resistance is high, and the slight fluctuation of operating parameters (such as temperature, pressure, gas-liquid ratio) can easily lead to unstable phenol removal efficiency. The traditional stripping method process involves two-stage tower countercurrent operation, and needs to accurately control the contact time and flow rate of steam and waste water, and the operation complexity is significantly higher than that of normal temperature and normal pressure process. In addition, the traditional stripping method cannot handle waste water containing alkali residue, and needs to transport alkali residue additionally, which not only increases the treatment cost, but also may cause environmental risk due to the leakage of toxic gases such as hydrogen sulfide.

[0004] The information disclosed in this BACKGROUND section is only for the purpose of increasing the understanding of the background of the present utility model and should not be regarded as an acknowledgement or any form of suggestion that this information forms prior art that is publicly known. CONTENT OF THE UTILITY MODEL

[0005] The utility model aims at providing a stripping phenol removal system to solve the above technical problems.

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

[0007] A stripping phenol removal system, comprising:

[0008] The stripping section is located in the upper section of the closed tower, and a plurality of water collecting tanks are arranged below the stripping section;

[0009] The regeneration section is located in the lower section of the closed tower, and a steam passage is arranged below the regeneration section;

[0010] The spraying system comprises a spraying assembly one, a spraying assembly two and a spraying assembly three; the spraying assembly one is located above the stripping section and connected with the preheater through a pipeline; the spraying assembly two is located above the regeneration section; and the spraying assembly three is located in the filler layer of the regeneration section.

[0011] As preferred, the preheater is internally provided with a phenolic wastewater pipeline; the bottom of the phenolic wastewater pipeline is a phenolic wastewater inlet, and the top of the phenolic wastewater pipeline is connected with the spraying assembly one through a pipeline.

[0012] As preferred, the top of the internal cavity of the preheater is connected with the water collecting tank through a pipeline, and the bottom of the internal cavity of the preheater is provided with a dephenolized wastewater outlet.

[0013] As preferred, the closed tower is externally provided with a blower; the air outlet of the blower is aligned with the steam passage, and the air inlet of the blower is communicated with the top of the closed tower through a pipeline.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] (1) The stripping dephenolization system of the utility model adopts three-section type filler design, improves the gas-liquid contact efficiency, enhances the mass transfer effect of phenolic substances, the use of structured packing reduces the pressure drop, improves the distribution uniformity of the fluid in the tower, and further improves the dephenolization efficiency.

[0016] (2) The stripping dephenolization system of the utility model recovers the waste heat in the wastewater through heat exchange, reduces the steam consumption, improves the energy utilization rate, reduces the dependence of the system on external heat source, and reduces the operation cost.

[0017] (3) The stripping dephenolization system of the utility model adopts multi-section spraying design, ensures that the lye and phenolic substances are fully contacted, improves the generation efficiency of sodium phenate, and the optimization of the spraying assembly reduces the amount of lye, and reduces the operation cost. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is the internal schematic view of the closed tower of the utility model;

[0019] MAIN REFERENCE MARK EXPLANATION:

[0020] 1, stripping section; 2, water collecting tank; 3, regeneration section; 4, spraying assembly one; 5, spraying assembly two; 6, spraying assembly three; 7, preheater; 8, blower. DETAILED DESCRIPTION

[0021] The technical scheme of the utility model patent will be described clearly and completely below, obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.

[0022] In the description of the utility model, it needs to explain that, if the terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawing, only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as the limitation of the utility model.

[0023] In the description of the utility model, it needs to explain that, unless otherwise explicitly specified and limited, if the terms such as "installation", "connection" and "connection" are understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, it can be mechanically connected, or it can be electrically connected, it can be directly connected, or indirectly connected through an intermediate medium, and it can be the connection between two elements inside. For the skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0024] Referring to the drawings Figure 1 The embodiment provides a stripping phenol removal system, which is simple in structure, small in power loss, high in mass transfer efficiency and large in operation flexibility. Specifically, the embodiment comprises the following steps:

[0025] The stripping section 1 is located in the upper section of the closed tower, and a plurality of water collecting tanks 2 are arranged below the stripping section 1;

[0026] The regeneration section 3 is located in the lower section of the closed tower, and a steam passage is arranged below the regeneration section 3;

[0027] The spraying system comprises a spraying assembly one 4, a spraying assembly two 5 and a spraying assembly three 6; the spraying assembly one 4 is located above the stripping section 1 and connected to the preheater 7 through a pipeline; the spraying assembly two 5 is located above the regeneration section 3; and the spraying assembly three 6 is located in the filler layer of the regeneration section 3.

[0028] In the embodiment, a phenolic wastewater pipeline is arranged in the preheater 7; a phenolic wastewater inlet is arranged at the bottom of the phenolic wastewater pipeline, and the top of the phenolic wastewater pipeline is connected to the spraying assembly one 4 through a pipeline; a cavity is arranged in the preheater 7, the top of the cavity is connected to the water collecting tank 2 through a pipeline, and a phenol removal wastewater outlet is arranged at the bottom of the cavity.

[0029] In addition, a blower 8 is arranged outside the closed tower; the air outlet of the blower 8 is aligned with the steam passage, and the air inlet of the blower 8 is connected to the top of the closed tower through a pipeline.

[0030] In actual use, the wastewater is first preheated by the preheater 7, then sprayed downward by the spraying assembly one 4 at the top of the closed tower, and then contacted with steam in countercurrent to transfer the phenolic substances in the wastewater to the gas phase to realize preliminary separation; then, the wastewater flows through the filler and is collected by the water collecting tank 2 below the stripping section 1 and then discharged.

[0031] The wastewater discharge process needs to flow through the pipeline and pass through the internal cavity of the preheater 7, and finally be discharged from the dephenolized wastewater outlet at the bottom of the internal cavity of the preheater 7, so that the high-temperature wastewater exchanges heat with the low-temperature medium, preheats the phenol-containing wastewater entering the stripping tower, and can cool the wastewater after dephenolization.

[0032] On the other hand, steam is sent from the steam pipeline closed at the bottom, and is in countercurrent contact with the wastewater from bottom to top for mass transfer, and is finally discharged from the top of the tower. The closed tower is divided into upper and lower sections. The upper section is the stripping section 1, which removes phenol in the wastewater by countercurrent steam. The lower section is the regeneration section 3, which absorbs phenol from the steam by alkali according to the countercurrent method. Hot lye is sprayed in the regeneration section to absorb phenolic substances in the gas phase to generate sodium phenate and recover.

[0033] The production of sodium phenate is realized by alkaline washing reaction. In the stripping dephenolization process, the phenol-containing wastewater first contacts with the lye (usually sodium hydroxide solution) to generate sodium phenate by neutralization reaction. The sodium phenate is dissolved in the aqueous phase and can be extracted from the wastewater by subsequent separation process (such as extraction or adsorption). The separation efficiency of sodium phenate directly affects the recovery rate of phenolic substances and the treatment effect of wastewater. Sodium phenate can be neutralized by carbon dioxide in industrial waste gas, which has environmental benefits and reduces greenhouse gas emissions. Not only the recovery of phenolic substances is realized, but also the high cost and corrosion problem of traditional dilute sulfuric acid neutralization method is avoided.

[0034] The foregoing description of specific exemplary embodiments of the present application is intended for purposes of illustration and example only. These descriptions are not intended to limit the application to the precise form disclosed, and obviously many changes and modifications can be suggested to one skilled in the art without departing from the spirit or scope of the application. It is chosen and described exemplary embodiments in order to explain the particular principles of the application and its practical application, so that those skilled in the art can implement and utilize various different exemplary embodiments of the application and various different choices and changes. The scope of the application is intended to be limited by the claims and their equivalents.

Claims

1. A stripping phenol removal system for use in a closed tower filled with packing material, characterized in that, include: The stripping section is located at the top of the closed tower, and multiple water collection tanks are installed below it. The regeneration section is located in the lower part of the closed tower, and a steam passage is provided below it; The spray system includes spray assembly one, spray assembly two, and spray assembly three; spray assembly one is located above the stripping section and is connected to the preheater via a pipeline; spray assembly two is located above the regeneration section; and spray assembly three is located in the packing layer of the regeneration section.

2. The stripping and phenol removal system according to claim 1, characterized in that, The preheater is equipped with a phenol-containing wastewater pipe; the bottom of the phenol-containing wastewater pipe is the phenol-containing wastewater inlet, and its top is connected to the spray assembly one through a pipe.

3. The stripping and phenol removal system according to claim 2, characterized in that, The top of the cavity inside the preheater is connected to the water collection tank via a pipe, and the bottom of the preheater is provided with a phenol removal wastewater outlet.

4. The stripping and phenol removal system according to claim 1, characterized in that, A blower is installed outside the sealed tower; the outlet of the blower is aligned with the steam passage, and its inlet is connected to the top of the sealed tower through a pipe.

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