Steam stripping composite sewage deamination system

Abstract

The utility model relates to a steam stripping composite sewage deamination system and belongs to the technical field of sewage treatment. Comprising a flash tower, and the flash tower comprises a steam stripping section, a flash section and a heating section from top to bottom; an outlet of the flash section is connected with a sewage pump through a pipeline; the sewage pump is connected with a high-temperature medium inlet of the heat exchanger; a high-temperature medium outlet of the heat exchanger is connected with the deamination sewage tank; a low-temperature medium inlet of the heat exchanger is connected with an outlet of the sewage tank through a sewage pipeline; a low-temperature medium outlet of the heat exchanger is connected with a heating section of the flash tower; a top outlet of the flash tower is connected with the saturated absorption tower; the saturated absorption tower is connected with the tail gas absorption tower; a spraying device II is arranged at the top of the tail gas absorption tower. According to the deamination tower, the problems that the steam consumption of the deamination tower is high, the heat of deaminated sewage cannot be recycled and a tail gas absorption device cannot dissipate heat in time are solved, the detection precision of delivered sewage is improved, and the stable deamination sewage treatment quality is ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of sewage treatment, specifically relates to a compound sewage deamination system of steam stripping. BACKGROUND

[0002] Steam stripping method is used to convert free ammonia in wastewater into ammonia gas escaping, and its treatment mechanism is a gas-liquid mass transfer process, that is, at high pH value, wastewater is closely contacted with steam, thereby reducing the ammonia concentration in wastewater. The driving force of mass transfer process is the difference between the partial pressure of ammonia in gas phase and the equilibrium partial pressure corresponding to the ammonia concentration in wastewater. Steam stripping method needs to use steam as working medium, ammonia from wastewater enters steam, and then is distilled at the top of the tower to become concentrated ammonia water for recovery, so that no post-treatment process is needed. The steam volume required by steam stripping is much smaller than the air volume required by air stripping method, so the equipment volume is small and the land occupation is less. The steam stripping method is more suitable for treating high-concentration ammonia-nitrogen wastewater with a concentration of more than 1000 mg / L, and the removal rate of ammonia-nitrogen can reach more than 99%, which is high in efficiency and good in technical maturity.

[0003] The compound stripping deamination tower is a device for removing ammonia gas in sewage. It combines heating, flashing and stripping. When the compound stripping deamination tower is used for deamination treatment, the following problems exist: (1) high steam consumption of the deamination tower; (2) high temperature of the sewage after deamination, and the heat cannot be recovered; (3) pH detection of the sewage after deamination needs to be sampled separately for laboratory detection, so that the real-time pH of the treated sewage cannot be reflected in time; (4) the internal part of the ammonia gas absorption tower uses a packing liquid distribution method, and dilute sulfuric acid is used as a circulating absorption liquid to absorb the discharged ammonia gas. When the dilute sulfuric acid is added to the circulating absorption liquid pipeline, a large amount of heat is generated, the heat cannot be taken away in time, the absorption liquid is rapidly gasified locally in the pipeline, and the pipeline vibrates violently. In summary, in order to ensure the stable and efficient operation of the device, the problems existing in the device need to be improved. UTILITY MODEL CONTENT

[0004] In view of the problems of high steam consumption of the deamination tower, heat recovery failure of the sewage after deamination and pipeline vibration of the absorption device circulating absorption liquid in the prior art, the utility model provides a compound sewage deamination system of steam stripping to solve the above problems.

[0005] The compound sewage deamination system of steam stripping comprises a flash tower, the flash tower is divided into a stripping section, a flash section and a heating section from top to bottom, the outlet of the flash section is connected with a sewage pump through a pipeline, the sewage pump is connected with the high-temperature medium inlet of a heat exchanger, the high-temperature medium outlet of the heat exchanger is connected with a deamination sewage tank, a branch pipeline is arranged between the sewage pump and the deamination sewage tank, an on-line pH meter is arranged on the branch pipeline, the low-temperature medium inlet of the heat exchanger is connected with the outlet of the sewage tank through a sewage pipeline, the low-temperature medium outlet of the heat exchanger is connected with the heating section of the flash tower, the top outlet of the flash tower is connected with a saturated absorption tower, the top of the saturated absorption tower is provided with a spraying device one, the spraying device one is connected with the bottom of the saturated absorption tower, the saturated absorption tower is connected with a tail gas absorption tower, the top of the tail gas absorption tower is provided with a spraying device two, and the spraying device two is connected with an absorption liquid storage tank two.

[0006] Further, the sewage pipeline is provided as a plurality of pipelines and is arranged in parallel.

[0007] Further, the spraying device two is a non-atomizing spraying device.

[0008] Further, the top inlet of the saturated absorption tower is connected with the stripping section of the flash tower through a pipeline, the bottom outlet of the saturated absorption tower is connected with the spraying device one through a pipeline, a circulating pump is arranged on the pipeline, and the absorption liquid in the saturated absorption tower is saturated ammonium sulfate solution.

[0009] Further, the bottom outlet of the tail gas absorption tower is connected with the spraying device two through a pipeline, a circulating pump is arranged on the pipeline, and the absorption liquid in the tail gas absorption tower is a mixed solution of dilute sulfuric acid and ammonium sulfate solution.

[0010] Further, the bottom outlet of the tail gas absorption tower is connected with the inlet of the absorption liquid storage tank through a pipeline, a circulating pump is arranged on the pipeline, and the absorption liquid in the tail gas absorption tower is a mixed solution of dilute sulfuric acid and ammonium sulfate solution.

[0011] The beneficial effects of the utility model lie in:

[0012] (1) The compound sewage deamination system of steam stripping provided by the utility model, through the heat exchanger, the heat in the deamination sewage separated by the flash evaporation section is reused, and the sewage to be treated before entering the flash evaporation tower is heated. After long time monitoring, the temperature of the deamination sewage is reduced from an average of 68.8 DEG C to an average of 52.5 DEG C; the temperature of the sewage to be treated before entering the flash evaporation tower is increased from an average of 33.5 DEG C to 51.2 DEG C. Through the method, the steam amount used by the flash evaporation tower is reduced, and through calculation, the steam unit consumption of the flash evaporation tower is reduced from 0.032 t / t to 0.021 t / t, and the steam unit consumption reduction reaches 34.38 %.

[0013] (2) The packing liquid distribution mode in the tail gas absorption tower is replaced by a spraying mode. Thus, the problem that a large amount of heat generated by adding sulfuric acid into the absorption tower cannot be taken away in time, causing the absorption liquid to be rapidly gasified and the pipeline to be violently vibrated is solved, and the safety accidents caused by pipeline rupture due to vibration are prevented.

[0014] (3) A branch is arranged between the original sewage pump and the deamination sewage tank, and an online pH meter is installed, the detection accuracy is increased from 2 % to 100 %, the detection precision of the sewage to be sent out is improved, and the deamination sewage treatment quality is stable. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical schemes in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows, and obviously, other drawings can be obtained by the drawings for the ordinary skilled in the art without creative labor.

[0016] Figure 1 It is a structural schematic view of the utility model.

[0017] In the figure, 1 is a flash evaporation tower, 2 is a sewage pump, 3 is a sewage pipeline, 4 is a heat exchanger, 5 is an online pH meter, 6 is a sewage tank, 7 is a flash evaporation section, 8 is a saturated absorption tower, 9 is a tail gas absorption tower, 10 is a heating section, 11 is a stripping section, 12 is a deamination sewage tank, 13 is an absorption liquid storage tank, 14 is a spraying device one, and 15 is a spraying device two. DETAILED DESCRIPTION

[0018] In order to make the personnel in the technical field better understand the technical schemes in the utility model, the technical schemes in the embodiments of the utility model will be clearly and completely described in combination with the drawings in the embodiments of the utility model as follows, and obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all the other embodiments obtained by the ordinary skilled in the art without creative labor should belong to the protection range of the utility model.

[0019] Example 1

[0020] A steam stripping combined wastewater deamination system, comprising: a flash tower 1, the flash tower 1 is divided into a stripping section 11, a flash section 7 and a heating section 10 from top to bottom; the outlet of the flash section 7 is connected with a wastewater pump 2 through a pipeline; the wastewater pump 2 is connected with the high-temperature medium inlet of a heat exchanger 4; the high-temperature medium outlet of the heat exchanger 4 is connected with a deamination wastewater tank 12; a branch pipe is further arranged between the wastewater pump 2 and the deamination wastewater tank 12, and an online pH meter 5 is arranged on the branch pipe; the low-temperature medium inlet of the heat exchanger 4 is connected with the outlet of a wastewater tank 6 through a wastewater pipeline 3; the low-temperature medium outlet of the heat exchanger 4 is connected with the heating section 10 of the flash tower 1; the top outlet of the flash tower 1 is connected with a saturated absorption tower 8; a spraying device one 14 is arranged at the top of the saturated absorption tower 8; the saturated absorption tower 8 is connected with a tail gas absorption tower 9; a spraying device two 15 is arranged at the top of the tail gas absorption tower 9; the spraying device two 15 is connected with an absorption liquid tank 13.

[0021] Example 2

[0022] A steam stripping combined wastewater deamination system, comprising: a flash tower 1, the flash tower 1 is divided into a stripping section 11, a flash section 7 and a heating section 10 from top to bottom; the outlet of the flash section 7 is connected with a wastewater pump 2 through a pipeline; the wastewater pump 2 is connected with the high-temperature medium inlet of a heat exchanger 4; the high-temperature medium outlet of the heat exchanger 4 is connected with a deamination wastewater tank 12; a branch pipe is further arranged between the wastewater pump 2 and the deamination wastewater tank 12, and an online pH meter 5 is arranged on the branch pipe; the low-temperature medium inlet of the heat exchanger 4 is connected with the outlet of a wastewater tank 6 through a wastewater pipeline 3; the wastewater pipeline 3 is arranged in three and arranged in parallel; the low-temperature medium outlet of the heat exchanger 4 is connected with the heating section 10 of the flash tower 1; the top outlet of the flash tower 1 is connected with a saturated absorption tower 8; a spraying device one 14 is arranged at the top of the saturated absorption tower 8; a pipeline is connected between the bottom outlet of the saturated absorption tower 8 and the spraying device one 14, and a circulating pump is arranged on the pipeline; the absorption liquid in the saturated absorption tower is saturated ammonium sulfate solution; the saturated absorption tower 8 is connected with a tail gas absorption tower 9; a spraying device two 15 is arranged at the top of the tail gas absorption tower 9; the spraying device two 15 is a non-atomizing spraying device; the spraying device two 15 is connected with an absorption liquid storage tank 13; the top outlet of the tail gas absorption tower 9 is connected with the stripping section 11 of the flash tower 1 through a pipeline; the bottom outlet of the tail gas absorption tower 9 is connected with the inlet of the absorption liquid storage tank 13 through a pipeline, and a circulating pump is arranged on the pipeline; the absorption liquid in the tail gas absorption tower is a mixed solution of dilute sulfuric acid and ammonium sulfate.

[0023] Although the utility model has been described in detail by referring to the drawings and in conjunction with the preferred embodiments, the utility model is not limited thereto. Without departing from the spirit and essence of the utility model, those skilled in the art can make various equivalent modifications or replacements to the embodiments of the utility model, and these modifications or replacements shall be within the scope of the utility model. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the utility model, and all shall be covered within the protection scope of the utility model.

Claims

1. A combined sewage deamination system of steam stripping, comprising a flash tower, the flash tower having a stripping section, a flash section and a heating section from top to bottom respectively; the outlet of the flash section is connected with a sewage pump through a pipeline; characterized in that, The sewage pump is connected with the high-temperature medium inlet of the heat exchanger; the high-temperature medium outlet of the heat exchanger is connected with the deamination sewage tank; a branch pipe is further arranged between the sewage pump and the deamination sewage tank, and an on-line pH meter is arranged on the branch pipe; the low-temperature medium inlet of the heat exchanger is connected with the outlet of the sewage tank through a sewage pipeline; the low-temperature medium outlet of the heat exchanger is connected with the heating section of the flash tower; the top outlet of the flash tower is connected with the saturated absorption tower; a spraying device one is arranged at the top of the saturated absorption tower; the spraying device one is connected with an absorption liquid storage tank one; the saturated absorption tower is connected with the tail gas absorption tower; a spraying device two is arranged at the top of the tail gas absorption tower; and the spraying device two is connected with the absorption liquid storage tank.

2. The combined wastewater deaminating system of claim 1, wherein, The sewage pipeline is provided in plurality and is arranged in parallel.

3. The combined wastewater deaminating system of claim 1, wherein, The spraying device two is a non-atomizing spraying device.

4. The combined wastewater deaminating system of claim 1, wherein, The top outlet of the tail gas absorption tower is connected with the stripping section of the flash tower through a pipeline.

5. The combined wastewater deaminating system of claim 1, wherein the steam stripping is performed at a temperature of 60 to 100°C and a pressure of 0.1 to 0.5 MPa. The bottom outlet of the saturated absorption tower is connected with the spraying device one through a pipeline, and a circulating pump is arranged on the pipeline.

6. The combined wastewater deaminating system of claim 5, wherein, The absorption liquid in the saturated absorption tower is water.

7. The combined wastewater deaminating system of claim 1, wherein, The bottom outlet of the tail gas absorption tower is connected with the inlet of the absorption liquid storage tank through a pipeline, and a circulating pump is arranged on the pipeline.

8. The combined wastewater deaminating system of claim 7, wherein, The absorption liquid in the tail gas absorption tower is a mixed solution of dilute sulfuric acid and ammonium sulfate solution.

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