CN107469575A - A kind of deammoniation tower suitable for MVR evaporator indirect steams - Google Patents

Abstract

The invention provides a kind of deammoniation tower suitable for MVR evaporator indirect steams, including deammoniation tower body, rake distributor and acid circulating pump, rake distributor is located inside deammoniation tower and is connected with air inlet, distributor trunk and branch's bottom even passage, acid circulating pump is located on the ground beside deammoniation tower, the deammoniation tower body bottom portion is provided with acid and exported, middle and lower part is provided with air inlet, liquid level gauge liquid phase interface and the sour mouth of benefit, middle part is provided with recycle acid import, online pH meter, hand hole and absorbing liquid outlet, middle and upper part is provided with wire mesh demister, manhole and screen bath water inlet, top is provided with gas outlet and liquid level gauge gas phase interface.The present invention both ensure that gas scrubbing increase while reduce the internal structure that deammoniation tower body height simplifies deammoniation tower, and equipment investment is greatly reduced compared to packed absorber.

Description

A deammonization tower suitable for secondary steam of MVR evaporator

technical field

The invention relates to a deammonization tower suitable for secondary steam of an MVR evaporator, belonging to the technical field of environmental protection equipment.

Background technique

The treatment of leachate from urban waste landfills and incineration plants has always been a very difficult problem in the design, operation and management of landfills and incineration plants. The leachate mainly comes from precipitation and the embedded water of the garbage itself. Since many factors may affect the properties of the leachate during the flow of the liquid, including physical factors, chemical factors and biological factors, the properties of the leachate vary within a considerable range. Generally speaking, its pH value is between 4 and 9, COD is in the range of 2000 to 62000mg/L, BOD5 is from 600 to 45000mg/L, ammonia nitrogen content is usually 100 to 1000mg/L, heavy metal concentration and heavy metal in municipal sewage The concentration is basically the same. The leachate of urban waste landfill is a kind of high-concentration organic wastewater with complex components. If it is directly discharged into the environment without treatment, it will cause serious environmental pollution. For the purpose of protecting the environment, it is essential to treat the leachate.

The traditional leachate treatment process is a "biochemical + membrane filtration" treatment process, which will produce high-concentration concentrates that are difficult to handle. The new leachate "MVR evaporation + condensate biochemical" treatment method is more environmentally friendly because no concentrated liquid is produced, but secondary steam containing high concentrations of ammonia will be generated during the evaporation process, which is required to ensure that the subsequent biochemical water quality meets the standards. Part of the ammonia in the secondary steam is removed through the deammonization unit. The traditional absorption tower adopts packing absorption tower. The internal structure of the equipment is relatively complicated and the height of the tower body is high. In actual operation, it is prone to blockage and frequent maintenance. Therefore, a deamination tower with simple structure and anti-blocking is needed.

Contents of the invention

Aiming at the existing technical problems, the present invention provides a new type of ammonia removal tower, which has a simple structure and low cost and can remove excess ammonia nitrogen in steam according to the removal rate of ammonia nitrogen in the biochemical system.

Technical scheme of the present invention is:

A deamination tower suitable for the secondary steam of the MVR evaporator, including a deamination tower body, the deamination tower body is divided into upper, middle, lower parts and a cylindrical structure with an elliptical head, and the middle and lower parts of the deamination tower body are horizontally oriented It is equipped with an air inlet, a rake distributor, a liquid level gauge liquid phase interface and an acid supply port, wherein the liquid level gauge liquid phase interface is located below the minimum liquid level in the tower, and the rake type distributor is located inside the deamination tower and the air inlet Connected, the vent holes are evenly distributed at the bottom of the main trunk and branches of the rake distributor. The bottom of the deamination tower body is provided with an acid outlet downward.

Wherein the inlet of the circulating absorption liquid is connected with the acid outlet through the acid circulation pump; the outlet of the absorption liquid is installed on the pipeline connected with the inlet of the circulating absorption liquid and the acid outlet; the inlet of the circulating absorption liquid is connected with the spray head, and the spray head is connected Placed at the upper end of the rake distributor; the middle and upper tower body is equipped with an absorption liquid spray device, and the tower body is equipped with a manhole; the upper part of the deamination tower body is equipped with a gas outlet upward, and a liquid level gauge gas phase interface is installed horizontally.

Further, the above-mentioned absorbing liquid spraying device is a wire mesh demister inside the tower and spray head 2; the spray head 2 is arranged at the upper end of the wire mesh demister and communicates with the wire mesh cleaning water inlet outside the tower.

Further, the online pH meter is installed on the pipeline connecting the circulating acid inlet and the acid outlet.

Further, the above-mentioned circulating absorption liquid inlet and screen cleaning water inlet are respectively arranged on the hand hole and the manhole.

Further, the inner surface of the above-mentioned deamination tower body adopts an anti-corrosion coating; the outer surface of the deamination tower body deamination tower is provided with insulation equipment.

Advantage of the present invention compared with prior art:

1. In the present invention, a rake distributor is set at the air inlet to ensure the uniform distribution of gas;

2. The invention installs a wire mesh demister and a wire mesh cleaning nozzle on the upper part of the deamination tower, which effectively prevents the entrainment of mist in the gas and greatly reduces the corrosion of subsequent pipelines and equipment;

3. The present invention is equipped with an online pH meter, which can accurately control the acid concentration of the absorption liquid so as to adjust the removal rate of ammonia in the steam;

4. In the present invention, the inlet of the circulating absorption liquid and the inlet of the screen cleaning water are respectively arranged on the hand hole and the manhole, which not only facilitates the maintenance but also reduces the opening of the tower body;

5. The deamination tower of the present invention is equipped with an absorption liquid spraying device in the deamination tower body, which not only ensures the gas washing effect but also reduces the height of the deamination tower body, which greatly reduces equipment investment compared with the packed absorption tower.

6. The ammonia removal tower of the present invention can reduce the content of ammonia nitrogen in the secondary steam to 50-200 mg/L.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the A-A figure of Fig. 1;

Among them, 1-deamination tower body; 2-acid outlet; 3-air inlet; 4-rake distributor; 5-circulation absorption liquid inlet; 6-screen demister; 7-screen cleaning water inlet; 8-liquid level gauge interface; 9-liquid level gauge gas phase interface; 10-gas outlet; 11-absorption liquid outlet; 12; online pH meter; 13-acid supply port; 14-acid circulation pump; 15-spray Head one; 16-spray head two.

detailed description

Further explanation is made below in conjunction with accompanying drawing:

The present invention will be further described below in conjunction with specific examples, but the protection scope of the present invention is not limited thereto.

As shown in Figure 1, the deamination tower of the present invention comprises a deamination tower body 1, the bottom of the deamination tower body 1 is provided with an acid outlet 2, and the middle and lower part is provided with an air inlet 3, a rake distributor 4, a liquid level gauge liquid Phase port 8 and acid supply port 13, the middle part is provided with circulating absorption liquid inlet 5, absorption liquid outlet 11 and online pH meter 12, the middle and upper part is provided with wire mesh demister 6 and wire mesh cleaning water inlet 7, and the top is provided with liquid The gas phase interface 9 and gas outlet 10 of the potentiometer, and the acid circulation pump 14 are located on the ground next to the deamination tower.

The secondary steam produced by evaporation enters the deamination tower body 1 from the air inlet 3, is evenly distributed by the rake distributor 4, fully contacts with the circulating absorption liquid sprayed from top to bottom, and then is removed by the wire mesh demister 6 After entraining the mist, it is discharged through the air outlet 10. After the circulating absorption liquid flows out from the acid outlet 2, it is pressurized by the acid circulation pump 14 and then sent to the circulating absorption liquid inlet 5. The circulating absorption liquid inlet 5 is sprayed to the The rake distributor 4 performs cyclic absorption, and an online pH meter 12 is installed on the circulating absorption liquid pipeline. After the pH value of the circulating absorption liquid rises to the set value, part of the circulating absorption liquid is discharged through the absorption liquid outlet 11, and a certain concentration of The dilute sulfuric acid supplements the circulating absorption liquid from the acid replenishment port 13, and controls the liquid level in the tower through the liquid level interface 8 and the gas phase interface 9 of the liquid level gauge when draining and replenishing acid, and the spray head 2 passes through the wire mesh The demister cleaning water inlet 7 uses evaporative condensed water to intermittently clean the wire mesh demister 6 online to reduce the vapor pressure drop inside the deamination tower.

The secondary steam containing high-concentration ammonia gas produced by evaporation enters the main body of the deamination tower from the horizontal direction of the air inlet, and after being evenly distributed by the rake distributor, it fully contacts with the circulating absorption liquid sprayed from top to bottom to remove part of the ammonia gas After the entrained mist is removed by the wire mesh demister, it is discharged from the air outlet, and the circulating absorption liquid flows out from the acid outlet, pressurized by the acid circulation pump, and then sent to the circulating absorption liquid inlet for circulating absorption, and the circulating absorption liquid pipeline is installed with online pH According to the removal rate of ammonia in the secondary steam, the pH value of the absorption circulation liquid can be flexibly controlled. After the pH value of the circulation absorption liquid rises to the set value, the bypass of the absorption liquid outlet is opened to discharge part of the circulation absorption liquid. The configured dilute sulfuric acid of a certain concentration is used to supplement the circulating absorption liquid from the acid replenishing port. In order to prevent the liquid level in the tower from being too low when the circulating absorption liquid is discharged, the cavitation of the acid circulation pump and the liquid level in the tower being too high when the dilute sulfuric acid is replenished For high-submerged spargers, it is necessary to set up a double-flange liquid level gauge. The liquid level value is determined by the difference between the liquid phase pressure and the gas phase pressure of the liquid level gauge to ensure that the liquid level changes within a reasonable range. The secondary steam passes through the acid After washing, a large amount of acid will be entrained, and the sulfuric acid in the acid will corrode the subsequent compressor and reduce the life of the compressor. Therefore, it is necessary to install a wire mesh demister to remove the acid entrained in the secondary steam. The demister will gradually block during operation and increase the resistance so that the pressure of the secondary steam will drop. In order to ensure that the pressure of the secondary steam discharged from the deamination tower will not drop too much, it is necessary to use a suitable cleaning water inlet through the wire mesh demister. The cleaning medium intermittently cleans the wire mesh demister online to ensure the permeability of the wire mesh demister and reduce the vapor pressure drop inside the deamination tower.

The deamination tower of the present invention is equipped with an absorption liquid spray device and a wire mesh defoaming device in the deamination tower body, which not only ensures the gas washing effect, but also reduces the height of the deamination tower body, which is greatly reduced compared with the packed absorption tower. investment in equipment.

The above-mentioned embodiments are only used to explain the inventive concept of the present invention, but not to limit the protection of the rights of the present invention. Any substantive changes made to the present invention by using this concept should fall within the scope of protection of the present invention.

Claims (5)

1. A deamination tower suitable for MVR evaporator secondary steam is characterized in that, comprising a deamination tower body, The body of the deamination tower is divided into upper, middle and lower parts and a cylindrical structure with an elliptical head, The lower part of the deamination tower body is horizontally provided with an air inlet, a rake distributor, a liquid level gauge liquid phase interface and an acid replenishment port, wherein the liquid level gauge liquid phase interface is located below the lowest liquid level in the tower, The rake sparger is located inside the deamination tower and connected to the air inlet, and the air holes are evenly distributed on the trunk and branch bottom of the rake sparger, The bottom of the deamination tower body is provided with an acid outlet downwards, The central part of the deamination tower body is horizontally provided with a circulating absorption liquid inlet, a hand hole and an absorption liquid outlet, Wherein, the inlet of the circulating absorption liquid is connected with the outlet of the acid through an acid circulation pump; the outlet of the absorption liquid is installed on the pipeline connecting the inlet of the circulating absorption liquid with the outlet of the acid; The inlet of the circulating absorption liquid communicates with the spray head one, and the spray head one is placed at the upper end of the rake distributor; An absorption liquid spraying device is arranged in the upper and middle tower body, and a manhole is arranged outside the tower body; The upper part of the deamination tower body is provided with a gas outlet upwards, and a liquid level gauge gas phase interface is provided horizontally. 2. deamination tower as claimed in claim 1, is characterized in that, described absorption liquid spray device is wire mesh demister and spray two in the tower body; Described spray two is arranged on the side of wire mesh demister The upper end is connected with the screen cleaning water inlet outside the tower body. 3. The deamination tower according to claim 1 or 2, wherein the online pH meter is installed on the pipeline connecting the circulating acid inlet and the acid outlet. 4. The deamination tower according to claim 1 or 2, characterized in that, the inlet of the circulating absorption liquid and the inlet of the screen cleaning water are respectively arranged on the hand hole and the manhole. 5. The deamination tower according to claim 1 or 2, characterized in that, the inner surface of the deamination tower body adopts an anti-corrosion coating; the outer surface of the deamination tower body deamination tower is provided with heat preservation equipment.