A new type of ammonium sulfate mother liquor crystallization tank

Abstract

The present invention relates to a novel ammonium sulfate mother liquor crystallization tank, comprising a crystallization tank body, an ammonium sulfate mother liquor inlet pipe and an ammonium sulfate clear liquid outlet pipe; the crystallization tank body is divided into a clear liquid extraction section, a feeding section and a crystallization precipitation section from top to bottom; an ammonium sulfate mother liquor inlet is arranged on one side of the upper part of the feeding section, and the ammonium sulfate mother liquor inlet pipe is arranged along the tangent direction of the crystallization tank body; the ammonium sulfate clear liquid outlet pipe is composed of a tapered tube, a 90° elbow and a straight tube, and the full flow port is arranged at the center of the clear liquid extraction section. The present invention adopts a multi-point, tangential feeding method, the diameter of the clear liquid extraction section is smaller than the diameter of the feeding section provided with the ammonium sulfate mother liquor inlet, and the full flow port of the clear liquid outlet pipe is located at the center of the clear liquid extraction section, which can achieve liquid crystal separation more efficiently and minimize the amount of ammonium sulfate crystals brought out by the ammonium sulfate clear liquid.

Description

Technical Field

[0001] The invention relates to the technical field of ammonia recovery in coking coal gas purification, and in particular to a novel ammonium sulfate mother liquor crystallization tank. Background Art

[0002] Ammonia is a nitrogen compound and a byproduct of the coal coking process. Generally, dry coal contains about 2% nitrogen, of which 40% to 50% enters the raw gas, most of which forms ammonia, and a small part forms hydrogen cyanide and pyridine.

[0003] At present, the saturator method is generally used to directly remove ammonia from coal gas, specifically: sulfuric acid is directly sprayed on coal gas in the saturator to produce ammonium sulfate, and when the ammonium sulfate mother liquor in the saturator reaches the solubility limit of ammonium sulfate, ammonium sulfate crystals are precipitated. This reaction is a reversible reaction, and the ammonium sulfate crystal mother liquor containing ammonium sulfate crystals should be pumped to the crystallization tank in time for crystallization precipitation, and the ammonium sulfate clear liquid flows back to the saturator, and the precipitated crystal liquid flows to the centrifuge for centrifugal separation. The ammonium sulfate crystals are sent to the vibrating fluidized bed dryer, and the centrifuged mother liquor and the full-flowing ammonium sulfate clear liquid are returned to the saturator. After the ammonium sulfate concentration is reduced, it is used to continue spraying to recover ammonia, and sulfuric acid should be added at the same time.

[0004] At present, the crystallization tank used for ammonium sulfate crystallization mother liquor in China usually adopts a structure with a cylindrical upper part with equal cross-section and a conical lower part, which is convenient for timely extraction of all crystal precipitation. However, the separation effect of crystallization and precipitation is not very ideal. Since the feed position is too high and there is no room for adjustment, the full flow of clear liquid often brings out the ammonium sulfate crystals. Summary of the invention

[0005] The present invention provides a novel ammonium sulfate mother liquor crystallization tank, which adopts a multi-point, tangential feeding method, the diameter of a clear liquid extraction section is smaller than the diameter of a feeding section provided with an ammonium sulfate mother liquor inlet, and the full flow port of a clear liquid outlet pipe is located at the center of the clear liquid extraction section, so that liquid crystal separation can be achieved more efficiently, and the amount of ammonium sulfate crystals brought out by the ammonium sulfate clear liquid is minimized.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A novel ammonium sulfate mother liquor crystallization tank comprises a crystallization tank body, an ammonium sulfate mother liquor inlet pipe and an ammonium sulfate clear liquid outlet pipe; the crystallization tank body is divided into a clear liquid extraction section, a feed section and a crystallization precipitation section from top to bottom, the clear liquid extraction section and the feed section are both cylindrical structures, the crystallization precipitation section is a downwardly contracted conical structure, and the diameter of the clear liquid extraction section is smaller than the diameter of the feed section; an ammonium sulfate mother liquor inlet is arranged on one side of the upper part of the feed section, and the ammonium sulfate mother liquor inlet pipe is arranged along the tangent direction of the crystallization tank body One end of the ammonium sulfate mother liquor inlet pipe is connected to the ammonium sulfate mother liquor inlet, and the other end is connected to the external ammonium sulfate mother liquor pipeline; the ammonium sulfate clear liquid outlet pipe is composed of a tapered tube, a 90° elbow and a straight tube, the tapered tube is large at the top and small at the bottom, and the large end is a full flow port, and the full flow port is located at the center of the clear liquid extraction section; one end of the 90° elbow is connected to the bottom end of the full flow pipe, and the other end is connected to one end of the horizontally arranged straight tube, and the other end of the straight tube passes through the side wall of the crystallization tank body and is connected to the external ammonium sulfate clear liquid pipeline.

[0008] There are multiple ammonium sulfate mother solution inlets and ammonium sulfate mother solution inlet pipes, which are evenly arranged one by one along the height of the crystallization tank body.

[0009] There are three ammonium sulfate mother liquor inlet and three ammonium sulfate mother liquor inlet pipes.

[0010] The ammonium sulfate mother liquor inlet is arranged on the side wall of the crystallization tank body extending from the feed section to the outside of the clear liquid extraction section.

[0011] The difference between the diameter of the clear liquid extraction section and the diameter of the feed section is 400-600 mm.

[0012] The top of the crystallization tank body is provided with an observation hole, a discharge port and a spare port.

[0013] A plurality of ear seats are arranged on the outer side of the lower part of the feeding section.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1) multiple ammonium sulfate mother liquor inlet pipes for tangential feeding are provided, and feeding is switched at different heights according to the feeding amount of ammonium sulfate mother liquor and the crystal content in the ammonium sulfate clear solution, so as to enhance the separation effect of ammonium sulfate crystals and ammonium sulfate clear solution in the crystallization tank;

[0016] 2) After tangential feeding, the heavy ammonium sulfate crystals will settle downward along the side wall of the crystallization tank body due to the effects of gravity and centrifugal force, and the ammonium sulfate clear liquid will flow upward and toward the center. Therefore, the diameter of the clear liquid extraction section at the upper part of the feeding section is reduced to prevent the ammonium sulfate crystals from being carried out of the crystallization tank by a small amount of ammonium sulfate clear liquid floating along the tank wall;

[0017] 3) After adopting tangential feeding, under the action of centrifugal force, the concentration of ammonium sulfate crystals in the center of the crystallization tank is the lowest, so the full flow port of the clear liquid extraction pipe is inserted into the center of the clear liquid extraction section to minimize the amount of ammonium sulfate crystals entrained in the extracted ammonium sulfate clear liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a novel ammonium sulfate mother liquor crystallization tank described in the present invention.

[0019] Figure 2 yes Figure 1 Top view of the .

[0020] In the figure: 1. Crystallization tank body 11. Clear liquid extraction section 12. Feeding section 13. Crystallization precipitation section 2. Ammonium sulfate mother liquid inlet pipe 3. Ammonium sulfate clear liquid outlet pipe 4. Release port 5. Observation hole 6. Reserve port 7. Ear seat DETAILED DESCRIPTION

[0021] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings:

[0022] like Figure 1 , Figure 2 As shown, a novel ammonium sulfate mother liquor crystallization tank of the present invention comprises a crystallization tank body 1, an ammonium sulfate mother liquor inlet pipe 2 and an ammonium sulfate clear liquid outlet pipe 3; the crystallization tank body 1 is divided into a clear liquid extraction section 11, a feeding section 12 and a crystal precipitation section 13 from top to bottom, the clear liquid extraction section 11 and the feeding section 12 are both cylindrical structures, the crystal precipitation section 13 is a downwardly contracted conical structure, and the diameter of the clear liquid extraction section 11 is smaller than the diameter of the feeding section 12; an ammonium sulfate mother liquor inlet is arranged on one side of the upper part of the feeding section 12, and the ammonium sulfate mother liquor inlet pipe 3 is arranged on the upper side of the feeding section 12. 2 is arranged tangentially along the crystallization tank body 1, one end of the ammonium sulfate mother liquor inlet pipe 2 is connected to the ammonium sulfate mother liquor inlet, and the other end is connected to the external ammonium sulfate mother liquor pipeline; the ammonium sulfate clear liquid outlet pipe 3 is composed of a tapered pipe, a 90° elbow pipe and a straight pipe, the tapered pipe is large at the top and small at the bottom, and the large end is a full flow port, and the full flow port is arranged at the center of the clear liquid extraction section 11; one end of the 90° elbow pipe is connected to the bottom end of the full flow pipe, and the other end is connected to one end of the horizontally arranged straight pipe, and the other end of the straight pipe passes through the side wall of the crystallization tank body 1 and is connected to the external ammonium sulfate clear liquid pipeline.

[0023] The ammonium sulfate mother solution inlet and the ammonium sulfate mother solution inlet pipe 2 are both multiple and are evenly arranged one by one along the height direction of the crystallization tank body 1 .

[0024] The number of the ammonium sulfate mother solution inlet and the number of the ammonium sulfate mother solution inlet pipes 2 are both 3.

[0025] The ammonium sulfate mother liquor inlet is provided on the side wall of the crystallization tank body 1 where the feed section 12 extends outside the clear liquid extraction section 11 .

[0026] The difference between the diameter of the clear liquid extraction section 11 and the diameter of the feed section 12 is 400-600 mm.

[0027] The top of the crystallization tank body 1 is provided with an observation hole 5, a discharge port 4 and a standby port 6.

[0028] A plurality of ear seats 7 are provided on the outer side of the lower portion of the feed section 12 .

[0029] The crystallization tank body 1 of the present invention adopts a structure with two cylindrical sections at the upper part and a conical section at the lower part, which are respectively a clear liquid extraction section 11, a feed section 12 and a crystal precipitation section 13. Among them, the clear liquid extraction section 11 has a small diameter, and the feed section 12 has a large diameter, and the diameter difference between the two is 400-600 mm. The position of the diameter change is higher than the uppermost ammonium sulfate mother liquor inlet ( Figure 1 The height A1) shown in the figure prevents the ammonium sulfate clear liquid from bringing out the ammonium sulfate crystals when floating up along the side wall of the crystallization tank body 1.

[0030] The ear seat 7 is installed on the outside of the feed section 12 with the largest diameter, and is used to support the entire crystallization tank when the equipment is installed.

[0031] The ammonium sulfate mother liquor inlet pipe 2 ( Figure 1 A1~A3) shown in the figure are arranged in the vertical direction and are feed pipes arranged along the tangential direction of the crystallization tank body 1. The purpose of the tangential arrangement is to make the ammonium sulfate mother liquor produce rotational motion inside the crystallization tank body 1 after entering the crystallization tank body 1. The purpose of vertically arranging multiple ones is to switch different feed heights according to the feed amount and the content of crystals in the ammonium sulfate clear liquid, thereby effectively enhancing the separation effect of ammonium sulfate crystals and ammonium sulfate clear liquid.

[0032] The full flow port on the ammonium sulfate clear liquid outlet pipe 3 extends into the center of the clear liquid extraction section 11, which can minimize the amount of ammonium sulfate crystals carried out.

[0033] In the crystallization tank body 1 , the ammonium sulfate crystals separated from the ammonium sulfate mother liquor gather outward and downward, flow downward along the side wall of the crystallization precipitation section 13 , and are finally discharged from the ammonium sulfate crystal outlet at the bottom of the crystallization tank body 1 .

[0034] The observation hole 5 is located at the top center of the crystallization tank body 1, just above the full flow port, and is used for operators to observe the full flow effect of the ammonium sulfate clear solution.

[0035] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A novel ammonium sulfate mother liquor crystallization tank, characterized in that: The invention comprises a crystallization tank body, an ammonium sulfate mother liquor inlet pipe and an ammonium sulfate clear liquor outlet pipe; the crystallization tank body is divided into a clear liquor extraction section, a feeding section and a crystallization precipitation section from top to bottom, the clear liquor extraction section and the feeding section are both cylindrical structures, the crystallization precipitation section is a conical structure that contracts downward, and the diameter of the clear liquor extraction section is smaller than the diameter of the feeding section; an ammonium sulfate mother liquor inlet is arranged on one side of the upper part of the feeding section, the ammonium sulfate mother liquor inlet pipe is arranged along the tangent direction of the crystallization tank body, one end of the ammonium sulfate mother liquor inlet pipe is connected to the ammonium sulfate mother liquor inlet, and the other end is connected to the An external ammonium sulfate mother liquor pipeline; the ammonium sulfate mother liquor inlet and the ammonium sulfate mother liquor inlet pipe are both multiple and evenly arranged one by one along the height direction of the crystallization tank body; the ammonium sulfate clear liquid outlet pipe is composed of a tapered tube, a 90° elbow and a straight tube, the tapered tube is larger at the top and smaller at the bottom, and the larger end is a full flow port, the full flow port is arranged at the center of the clear liquid extraction section; one end of the 90° elbow is connected to the bottom end of the full flow pipe, and the other end is connected to one end of a horizontally arranged straight tube, and the other end of the straight tube passes through the side wall of the crystallization tank body and is connected to the external ammonium sulfate clear liquid pipeline.

2. A novel ammonium sulfate mother solution crystallization tank according to claim 1, characterized in that, There are three ammonium sulfate mother liquor inlet and three ammonium sulfate mother liquor inlet pipes.

3. A novel ammonium sulfate mother solution crystallization tank according to claim 1, characterized in that, The ammonium sulfate mother liquor inlet is arranged on the side wall of the crystallization tank body extending from the feed section to the outside of the clear liquid extraction section.

4. A novel ammonium sulfate mother solution crystallization tank according to claim 1, characterized in that, The difference between the diameter of the clear liquid extraction section and the diameter of the feed section is 400-600 mm.

5. A novel ammonium sulfate mother solution crystallization tank according to claim 1, characterized in that: The top of the crystallization tank body is provided with an observation hole, a discharge port and a spare port.

6. A novel ammonium sulfate mother solution crystallization tank according to claim 1, characterized in that: A plurality of ear seats are arranged on the outer side of the lower part of the feeding section.

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