Polyformaldehyde reboiling substance separation device

Abstract

The utility model relates to the technical field of polyformaldehyde reboiling residue treatment, in particular to a polyformaldehyde reboiling residue separation device, which comprises a reboiling residue rectifying tower, a first reboiling residue storage tank, a reboiling residue re-separation tower, a product storage tank and a second reboiling residue storage tank, and a top outlet of the reboiling residue rectifying tower is fixedly communicated with a first product discharging pipeline. The device is reasonable and compact in structure and convenient to use, a series of equipment and pipelines such as the reboiling substance re-separation tower are innovatively and additionally arranged behind the reboiling substance rectifying tower, re-separation is carried out through the reboiling substance re-separation tower, reboiling substances are effectively re-separated, the quality of a final product is not influenced, and the production cost is reduced. And the problems of equipment scaling and blockage caused by reboiling substance accumulation in the existing trioxymethylene production device are avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to polyformaldehyde reboiler processing technical field, is a polyformaldehyde reboiler separation device. BACKGROUND

[0002] Polyformaldehyde (POM) is a kind of high-density, high-crystallinity linear polymer without side chain. Generally speaking, the purity of the first monomer trioxymethylene plays a decisive role in the physical properties and thermal stability of the polymer. During the production of trioxymethylene, impurities such as polyoxymethylene dimethyl ether, trioxaheptane and tetraoxaoctane are produced, which have a negative impact on the polymerization reaction of polyformaldehyde and need to be purified.

[0003] The traditional separation method is to separate the reboiler by using a rectification column. During the separation process, high-purity trioxymethylene product can be obtained from the top of the column, and the reboiler at the bottom is pumped to the post-recovery system by the discharge pump. This treatment method can only achieve the separation of part of the reboiler to a certain extent, and the reboiler is always circulating in the system, but the reboiler is not really removed from the system. Long-term circulation may cause accumulation of reboiler in the system, affecting the normal operation of the equipment, such as causing fouling and blockage of the equipment, thereby reducing the service life of the equipment and increasing the maintenance cost. The accumulation of reboiler also has a negative impact on product quality. Since the reboiler contains impurities such as acetal, dioxolane and trioxymethylene, these impurities will enter the subsequent production process, affecting the thermal stability and physical properties of the polymer, and causing fluctuations in product quality.

[0004] Therefore, although the current traditional rectification column has improved the purity of the monomer, there are still problems: 1) As the reboiler accumulates in the system, impurities are produced and enter the subsequent production process, affecting the quality of the final product; 2) The accumulation of reboiler causes fouling and blockage of the equipment, affecting the use and maintenance of the equipment. SUMMARY

[0005] The polyformaldehyde reboiler separation device provided by the utility model overcomes the above-mentioned deficiencies of the prior art and effectively solves the problem of fouling and blockage of the equipment caused by the accumulation of reboiler in the existing trioxymethylene production device.

[0006] The technical scheme of the utility model is realized through the following measures: a polyformaldehyde reboiler separation device, including reboiler rectifying tower, first reboiler storage tank, reboiler separation tower, product storage tank and second reboiler storage tank, the upper inlet of reboiler rectifying tower is fixedly connected with raw material feeding pipeline, the top outlet of reboiler rectifying tower is fixedly connected with first product discharging pipeline, the lower outlet of reboiler rectifying tower and the top inlet of first reboiler storage tank are fixedly connected with reboiler discharging pipeline, the lower outlet of first reboiler storage tank and the upper inlet of reboiler separation tower are fixedly connected with first treatment pipeline, the top outlet of reboiler separation tower and the inlet of product storage tank are fixedly connected with second product discharging pipeline, the lower outlet of reboiler separation tower and the top inlet of second reboiler storage tank are fixedly connected with second treatment pipeline, and the outlet of second reboiler storage tank is fixedly connected with fire torch pipeline.

[0007] The following is the further optimization or / and improvement of the above-mentioned utility model technical scheme:

[0008] The upper inlet of reboiler rectifying tower is fixedly connected with first reflux pipeline, the outlet of product storage tank is fixedly connected with product extraction pipeline, and the product extraction pipeline and the upper inlet of reboiler separation tower are fixedly connected with second reflux pipeline.

[0009] The first treatment pipeline is provided with first heat exchanger, the first heat exchanger heat source inlet and the second treatment pipeline are fixedly connected with first circulation pipeline, and the first circulation pipeline, the second treatment pipeline and the first heat exchanger heat source outlet are fixedly connected with second circulation pipeline.

[0010] The bottom of reboiler rectifying tower and reboiler separation tower is provided with reboiler, the bottom outlet of reboiler rectifying tower and the bottom outlet of reboiler separation tower are fixedly connected with reflux feeding pipeline, and the top outlet of reboiler is fixedly connected with reflux discharging pipeline.

[0011] The second product discharging pipeline is provided with second heat exchanger and third heat exchanger, and the second heat exchanger and third heat exchanger cold source inlet and cold source outlet are fixedly connected with cooling medium inlet pipeline and cooling medium outlet pipeline.

[0012] The fire torch pipeline is provided with delivery pump, the reboiler discharging pipeline between first reflux pipeline and reboiler rectifying tower is provided with delivery pump, the product extraction pipeline between second reflux pipeline and product storage tank is provided with delivery pump, the first treatment pipeline between first reboiler storage tank and first heat exchanger is provided with delivery pump, and the second treatment pipeline between reboiler separation tower and first circulation pipeline is provided with delivery pump.

[0013] The utility model discloses reasonable and compact structure, convenient to use, its innovatively add series equipment and pipeline such as reboiler separation tower after reboiler rectifying tower, carry out reseparation through reboiler separation tower, and effectively reseparate reboiler, do not influence the quality of final product, avoid the problem that the equipment is scaled and blocked by the accumulation of reboiler. BRIEF DESCRIPTION OF DRAWINGS

[0014] BRIEF DESCRIPTION OF DRAWINGS Figure 1 It is the process flow schematic diagram of the utility model.

[0015] BRIEF DESCRIPTION OF DRAWINGS Figure 1 The coding in the figure is as follows: 1 is reboiler rectifying tower, 2 is first reboiler storage tank, 3 is reboiler separation tower, 4 is product storage tank, 5 is second reboiler storage tank, 6 is raw material feeding pipeline, 7 is first product discharge pipeline, 8 is reboiler discharge pipeline, 9 is first treatment pipeline, 10 is second product discharge pipeline, 11 is second treatment pipeline, 12 is fire torch feeding pipeline, 13 is first reflux pipeline, 14 is second reflux pipeline, 15 is product extraction pipeline, 16 is first heat exchanger, 17 is first circulation pipeline, 18 is second circulation pipeline, 19 is reboiler, 20 is reflux feeding pipeline, 21 is reflux discharge pipeline, 22 is second heat exchanger, 23 is third heat exchanger, 24 is cooling medium inlet pipeline, 25 is cooling medium outlet pipeline, 26 is delivery pump. DETAILED DESCRIPTION

[0016] The utility model is not limited by the following embodiments, and the specific implementation mode can be determined according to the technical scheme and actual situation of the utility model.

[0017] In the utility model, if no special instruction is given, the equipment and device used are all the equipment and device commonly known in the art. For example, reboiler rectifying tower 1 and reboiler separation tower 3 are all the equipment commonly known in the art.

[0018] In the utility model, in order to facilitate the description, the relative position relation of each component is all described according to the layout mode of the drawing of the specification, for example, the position relation of front, back, top, bottom, left, right is determined according to the layout direction of the drawing of the specification. Figure 1 Figure 1

[0019] The utility model will be further described in connection with the embodiment and drawing as follows:

[0020] Embodiment 1: as shown in the drawing, the raw material is fed into the first heat exchanger 16 through the raw material feeding pipeline 6, and the raw material is heated to the boiling point of the raw material through the first heat exchanger 16, and then the raw material is fed into the reboiler 19 through the reflux feeding pipeline 20. Figure 1 ​​As shown, the polyoxymethylene deboiler separation device includes a deboiler distillation column 1, a first deboiler storage tank 2, a deboiler reseparation column 3, a product storage tank 4, and a second deboiler storage tank 5. The upper inlet of the deboiler distillation column 1 is fixedly connected to a raw material feed pipeline 6, the top outlet of the deboiler distillation column 1 is fixedly connected to a first product discharge pipeline 7, the lower outlet of the deboiler distillation column 1 is fixedly connected to the top inlet of the first deboiler storage tank 2, the lower outlet of the first deboiler storage tank 2 is fixedly connected to the upper inlet of the deboiler reseparation column 3, the top outlet of the deboiler reseparation column 3 is fixedly connected to the inlet of the product storage tank 4, the lower outlet of the deboiler reseparation column 3 is fixedly connected to the top inlet of the second deboiler storage tank 5, and the outlet of the second deboiler storage tank 5 is fixedly connected to a flare delivery pipeline 12.

[0021] This invention sends polyoxymethylene (POM) to a reboiler distillation column 1 for distillation, collecting the high-purity trioxymethylene. The reboiler containing trioxymethylene is then sent to a reboiler reseparation column 3 for further separation. The high-purity trioxymethylene is collected and stored in a product storage tank 4. The reboiler containing no trioxymethylene and other impurities is sent to a flare for incineration, and the heat is used for power generation. This invention innovatively adds a series of equipment and pipelines, including a reboiler reseparation column 3, after the reboiler distillation column 1. The reseparation in the reboiler reseparation column 3 effectively separates the reboiler without affecting the quality of the final product, solving the problem of scaling and clogging caused by the accumulation of reboiler in existing trioxymethylene production equipment.

[0022] The above-mentioned polyoxymethylene reboiler separation device can be further optimized and / or improved according to actual needs:

[0023] Example 2: Its difference from Example 1 is as follows: (See attached) Figure 1 As shown, a first reflux line 13 is fixedly connected between the reboiler discharge line 8 and the upper inlet of the reboiler distillation column 1, a product collection line 15 is fixedly connected to the outlet of the product storage tank 4, and a second reflux line 14 is fixedly connected between the product collection line 15 and the upper inlet of the reboiler reseparation column 3.

[0024] During use, the separation efficiency is improved by adding a first return line 13 and a second return line 14.

[0025] Example 3: Its difference from Examples 1 to 2 is as follows: (See attached) Figure 1 As shown, a first heat exchanger 16 is provided on the first processing pipeline 9. A first circulation pipeline 17 is fixedly connected between the heat source inlet of the first heat exchanger 16 and the second processing pipeline 11. A second circulation pipeline 18 is fixedly connected between the second processing pipeline 11 and the heat source outlet of the first heat exchanger 16, and between the first circulation pipeline 17 and the second reboiler storage tank 5.

[0026] In use, the trioxane-containing reboiler in the first reboiler storage tank 2 exchanges heat with the reboiler sent out from the bottom of the reboiler separation column 3 through the first heat exchanger 16, and the trioxane-containing reboiler in the first reboiler storage tank 2 is warmed to a certain temperature before being sent into the reboiler separation column 3, and the reboiler sent out from the bottom of the reboiler separation column 3 is cooled to a certain temperature before being sent into the second reboiler storage tank 5 for temporary storage, thereby saving energy and reducing consumption.

[0027] Example 4: It is different from examples 1 to 3 in that, as shown in the attached Figure 1 boiler 19, and the reflux feed line 20 is fixedly communicated between the bottom outlet of the reboiler distillation column 1 and the bottom outlet of the reboiler separation column 3 and the bottom inlet of the reboiler 19, and the reflux discharge line 21 is fixedly communicated between the top outlet of the reboiler 19 and the lower inlet of the reboiler distillation column 1 and the lower inlet of the reboiler separation column 3.

[0028] In use, the reboiler 19 heats the bottom liquid of the reboiler distillation column 1 or the reboiler separation column 3 to make it partially vaporize, thereby providing the reboiler distillation column 1 or the reboiler separation column 3 with an upward vapor flow and providing the reboiler distillation column 1 and the reboiler separation column 3 with heat. According to the need, the reboiler 19 is provided with a steam inlet pipeline and a steam outlet pipeline at the heat source inlet and outlet, respectively, to provide the reboiler 19 with a heat source.

[0029] Example 5: It is different from examples 1 to 4 in that, as shown in the attached Figure 1 second heat exchanger 22 and the third heat exchanger 23 are fixedly communicated with the cooling medium inlet pipeline 24 and the cooling medium outlet pipeline 25 at the cold source inlet and the cold source outlet, respectively.

[0030] In use, the trioxane product at the top of the reboiler separation column 3 is sent into the product storage tank 4 after being cooled by the second heat exchanger 22 and the second heat exchanger 22.

[0031] Example 6: It is different from examples 1 to 5 in that, as shown in the attached Figure 1 According to the need, the flare pipeline 12 is provided with a delivery pump 26, the reboiler discharge pipeline 8 between the first reflux pipeline 13 and the reboiler distillation column 1 is provided with a delivery pump 26, the product production pipeline 15 between the second reflux pipeline 14 and the product storage tank 4 is provided with a delivery pump 26, the first treatment pipeline 9 between the first reboiler storage tank 2 and the first heat exchanger 16 is provided with a delivery pump 26, and the second treatment pipeline 11 between the reboiler separation column 3 and the first circulation pipeline 17 is provided with a delivery pump 26.

[0032] According to the need, the pipelines and equipment of the polyformaldehyde reboiler separation device can be provided with conventional valves, thermometers and pressure gauges and the like commonly known in the art according to the production needs.

[0033] The above technical features constitute embodiments of the present application, which have strong adaptability and implementation effects, and unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

[0034] The use process of the embodiment of the present application is as follows:

[0035] Firstly, polyformaldehyde (POM) is sent to the reboiler rectification tower 1 from the raw material feeding pipeline 6, and is rectified under a micro-positive pressure state with a tower bottom temperature of 127 DEG C and a tower top temperature of 117 DEG C, and the obtained trioxymethylene is sent out through the first product discharge pipeline 7, and the reboiler containing trioxymethylene at the tower bottom is sent to the first reboiler storage tank 2 through the reboiler discharge pipeline 8 for temporary storage;

[0036] Then, the reboiler containing trioxymethylene in the first reboiler storage tank 2 is sent to the reboiler separation tower 3, and is separated under the conditions of a tower top pressure of 0.005 MPa to 0.015 MPa, a tower top temperature of 114 DEG C to 117 DEG C and a tower bottom temperature of 125 DEG C to 128 DEG C, and is separated by using the boiling point difference, and the trioxymethylene with a concentration of 99.99% is sent to the product storage tank 4 after being cooled by the second heat exchanger 22 and the third heat exchanger 23 on the second product discharge pipeline 10, and part of the trioxymethylene in the product storage tank 4 is sent out, and the other part is circulated to the reboiler separation tower 3 through the second reflux pipeline 14 (the material reflux ratio is 1.3 to 1.7);

[0037] Finally, the reboiler containing trioxymethylene and the like impurities is sent to the first heat exchanger 16 through the first circulation pipeline 17 to exchange heat with the reboiler containing trioxymethylene delivered from the first reboiler storage tank 2, and the reboiler containing trioxymethylene and the like impurities after being cooled is sent to the second reboiler storage tank 5 through the second circulation pipeline 18 for temporary storage, and the collected reboiler containing trioxymethylene and the like impurities is sent to a flare stack pipeline 12 for flare incineration treatment, and the heat is used for power generation.

Claims

1. A polyoxymethylene reboiler separation device, characterized in that... The system includes a distillation column, a first distillate storage tank, a distillate reseparation column, a product storage tank, and a second distillate storage tank. A feed pipeline is fixedly connected to the upper inlet of the distillation column, and a first product discharge pipeline is fixedly connected to the top outlet of the distillation column. A distillate discharge pipeline is fixedly connected between the lower outlet of the distillation column and the top inlet of the first distillate storage tank. A first processing pipeline is fixedly connected between the lower outlet of the first distillate storage tank and the upper inlet of the distillate reseparation column. A second product discharge pipeline is fixedly connected between the top outlet of the distillate reseparation column and the inlet of the product storage tank. A second processing pipeline is fixedly connected between the lower outlet of the distillate reseparation column and the top inlet of the second distillate storage tank. A flare delivery pipeline is fixedly connected to the outlet of the second distillate storage tank.

2. The polyoxymethylene reboiler separation device according to claim 1, characterized in that... A first reflux line is fixedly connected between the reboiler discharge pipeline and the upper inlet of the reboiler distillation column; a product collection pipeline is fixedly connected to the product storage tank outlet; and a second reflux line is fixedly connected between the product collection pipeline and the upper inlet of the reboiler reseparation column.

3. The polyoxymethylene reboiler separation device according to claim 1 or 2, characterized in that... A first heat exchanger is provided on the first processing pipeline. A first circulation pipeline is fixedly connected between the heat source inlet of the first heat exchanger and the second processing pipeline. A second circulation pipeline is fixedly connected between the second processing pipeline between the first circulation pipeline and the second reboiler storage tank and the heat source outlet of the first heat exchanger.

4. The polyoxymethylene reboiler separation device according to claim 1 or 2, characterized in that... Both the reboiler distillation column and the reboiler reseparation column are equipped with reboilers at the bottom. The bottom outlet of the reboiler distillation column and the bottom outlet of the reboiler reseparation column are fixedly connected to the bottom inlet of the reboiler, respectively. The top outlet of the reboiler is fixedly connected to the bottom inlet of the reboiler distillation column and the bottom inlet of the reboiler reseparation column, respectively, with a reflux outlet line.

5. The polyoxymethylene reboiler separation device according to claim 3, characterized in that... Both the reboiler distillation column and the reboiler reseparation column are equipped with reboilers at the bottom. The bottom outlet of the reboiler distillation column and the bottom outlet of the reboiler reseparation column are fixedly connected to the bottom inlet of the reboiler, respectively. The top outlet of the reboiler is fixedly connected to the bottom inlet of the reboiler distillation column and the bottom inlet of the reboiler reseparation column, respectively, with a reflux outlet line.

6. The polyoxymethylene reboiler separation device according to claim 1, 2, or 5, characterized in that... The second product discharge pipeline is equipped with a second heat exchanger and a third heat exchanger. The cold source inlet and cold source outlet of the second and third heat exchangers are fixedly connected to the cooling medium inlet pipeline and the cooling medium outlet pipeline.

7. The polyoxymethylene reboiler separation device according to claim 3, characterized in that... The second product discharge pipeline is equipped with a second heat exchanger and a third heat exchanger. The cold source inlet and cold source outlet of the second and third heat exchangers are fixedly connected to the cooling medium inlet pipeline and the cooling medium outlet pipeline.

8. The polyoxymethylene reboiler separation device according to claim 4, characterized in that... The second product discharge pipeline is equipped with a second heat exchanger and a third heat exchanger. The cold source inlet and cold source outlet of the second and third heat exchangers are fixedly connected to the cooling medium inlet pipeline and the cooling medium outlet pipeline.

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