Benzyl benzoate static crystallization and purification device

Abstract

The utility model relates to the technical field of sewage treatment, in particular to a benzyl benzoate static crystallization and purification device which comprises a container, the container is provided with a feed port and a discharge port, and at least three heat exchange pipelines are arranged in the container; the heat exchange pipeline comprises an inner pipe and an outer pipe, the outer pipe sleeves the outer side of the inner pipe, and the inner pipe and the outer pipe are coaxial; the outer wall of the inner pipe is thinner than the inner wall of the outer pipe, so that a gap is formed between the inner pipe and the outer pipe, the two ends of the gap are sealed, and water is contained in the gap; an inlet and an outlet of the inner pipe extend out of the container; an outlet of the inner pipe is communicated with the liquid storage tank; the device further comprises a switching valve. An outlet of the switching valve is connected to a liquid supply pipeline; the liquid supply pipeline is connected to at least three liquid supply branch pipes; the at least three liquid supply branch pipes are respectively communicated with inlets of inner pipes of the at least three heat exchange pipelines; two liquid inlets of the switching valve are respectively communicated with a cold liquid supply pipeline and a hot liquid supply pipeline; benzyl benzoate crystallization is more uniform, and purity and yield of benzyl benzoate crystallization purification are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to benzoic acid benzyl ester technical field, specifically in benzoic acid benzyl ester methyl ester purification device. BACKGROUND

[0002] Benzoic acid benzyl ester is often used as a solvent in perfumes and cosmetics, and also used in dyes and paints, usually colorless to yellowish liquid at room temperature. In the existing production of benzoic acid benzyl ester, in order to meet the requirement of high content of benzoic acid benzyl ester product, industrial grade benzoic acid benzyl ester (90% < benzoic acid benzyl ester content < 95%) is purified to fine grade benzoic acid benzyl ester (99.5% < benzoic acid benzyl ester content) by secondary rectification and secondary crystallization process.

[0003] In the existing static crystallizer, the temperature difference from the inlet to the outlet of the cold water is large, which can cause the thickness of the benzoic acid benzyl ester crystallization layer in the crystallization tube to be uneven. The uneven thickness of the crystallization layer can cause some areas of the early crystallized benzoic acid benzyl ester to be mixed with uncrystallized impurities and easily fall off from the inner wall of the crystallization tube, affecting the purity and yield of benzoic acid benzyl ester crystallization purification. SUMMARY

[0004] The utility model aims at providing a kind of benzoic acid benzyl ester static crystallization purification device to solve at least one of the above technical problems.

[0005] The technical problems solved by the utility model can be solved by the following technical solutions:

[0006] A kind of benzoic acid benzyl ester static crystallization purification device, including container, the container has feed inlet and discharge outlet.

[0007] The heat exchange pipeline includes inner tube and outer tube, the outer tube is sleeved on the outer side of inner tube, and the inner tube and outer tube are coaxial lines;

[0008] The outer wall of inner tube is thinner than the inner wall of outer tube, so that there is a gap between inner tube and outer tube, the gap is sealed at both ends, and water is contained in the gap;

[0009] The inner tube has an inlet and an outlet, and the inlet and outlet extend from the container;

[0010] The outlet of the inner tube is connected to the liquid storage pool;

[0011] It also includes a switching valve provided with two liquid inlets and one liquid outlet;

[0012] The outlet of the switching valve is connected to a liquid supply pipeline;

[0013] The liquid supply pipeline is connected to at least three liquid supply branch pipes through at least four branch pipe joints, and the at least three liquid supply branch pipes are respectively connected to the inlets of the inner tubes of the at least three heat exchange pipelines;

[0014] The two liquid inlets of the switching valve are communicated with a cold liquid supply pipeline and a hot liquid supply pipeline respectively.

[0015] The design first reduces the path length of the heat exchange pipeline in the container by arranging at least three heat exchange pipelines, reduces the temperature difference of the cold water from the inlet to the outlet, makes the benzyl benzoate crystallization more uniform, and improves the purity and yield of the benzyl benzoate crystallization purification; secondly, the heat exchange pipeline includes an inner tube and an outer tube, there is a gap between the inner tube and the outer tube, the gap is sealed at both ends, and water is contained in the gap; when the inner tube passes through cold water or hot water, the water is first cooled or heated, so that the temperature of the outer tube changes slowly and uniformly when the benzyl benzoate is cooled or heated; finally, by arranging a switching valve, the two liquid inlets of the switching valve are communicated with a cold liquid supply pipeline and a hot liquid supply pipeline respectively, and the cold water and the hot water are injected into the inner tube through the liquid supply pipeline, so that the temperature of the inner tube changes slowly, the benzyl benzoate crystallization is more uniform, and the purity and yield of the benzyl benzoate crystallization purification are improved.

[0016] The temperature is lower than 2 degrees, the benzyl benzoate is cooled to crystallize, and the temperature is higher than 30 degrees, the benzyl benzoate crystallization is heated to melt.

[0017] Preferably, the inner tube is arranged with heat exchange fins, one end of the heat exchange fins extends into the inner tube, and the other end extends into the gap surrounded by the inner tube, the outer tube and the inner wall of the container; the heat exchange fins can slow down the flow rate of water in the inner tube, and facilitate heat exchange of water on both sides of the inner tube.

[0018] Preferably, the heat exchange fins are arranged in at least two rows on the inner tube, and the heat exchange fins of the two rows are arranged in an interlaced manner; the interlaced arrangement further weakens the flow rate of water to enable efficient heat exchange of water on both sides of the inner tube.

[0019] Preferably, the outer wall of the outer tube is arranged with an outwardly extending annular ring; the upper side of the annular ring is arranged as a horizontal plane, and the lower side of the annular ring is arranged as a downwardly extending inclined plane; the annular ring facilitates the static crystallization of benzyl benzoate to adhere to the outer wall of the outer tube, preventing the crystallized benzyl benzoate from falling and affecting the yield of benzyl benzoate.

[0020] Preferably, the gap is an annular gap, the distance between the inner and outer rings at each position of the gap is less than one-third of the inner diameter of the inner tube and greater than one-fifth of the inner diameter of the inner tube; the sufficient specific heat capacity of the water in the gap ensures that the temperature rises slowly during heat exchange, preventing the temperature from changing dramatically, and the water does not change too much to cause the temperature to change too slowly.

[0021] Preferably, the two ends of the outer tube abut against the upper and lower inner walls of the container, the inner tube, the outer tube and the inner wall of the container surround a closed gap, and the upper and lower inner walls of the container constitute the length of the gap; the upper and lower inner walls of the container are covered with the outer tube, and the heating is more uniform.

[0022] Preferably, another switching valve provided with two liquid outlets and one liquid inlet is further included, referred to as a water outlet valve; the inlet of the water outlet valve is connected to a liquid outlet pipeline; the liquid outlet pipeline is connected to at least three liquid outlet branch pipes through a four-way branch joint; the at least three liquid outlet branch pipes are respectively communicated with the outlets of the inner pipes of the at least three heat exchange pipelines; the liquid storage pool is provided with two, which are a cold liquid storage pool and a hot liquid storage pool; the two liquid outlets of the water outlet valve are respectively communicated with a cold liquid storage pool and a hot liquid storage pool. The water outlet valve and the switching valve are synchronously switched, cold water supplied by the cold liquid supply pipeline is injected into the cold liquid storage pool after heat exchange through the inner pipe, and then the water in the cold liquid storage pool can be supplied to the cold liquid supply pipeline after refrigeration to realize cold water circulation and save energy; hot water supplied by the hot liquid supply pipeline is injected into the hot liquid storage pool after heat exchange through the inner pipe, and then the water in the hot liquid storage pool can be supplied to the cold liquid supply pipeline after heating to realize cold water circulation and save energy.

[0023] Preferably, the outer pipe is a copper outer pipe with a rough surface; the static crystallization of benzyl benzoate is attached to the outer wall of the outer pipe, so as to prevent the crystallized benzyl benzoate from falling off and affecting the yield of benzyl benzoate. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor. Among them:

[0025] Figure 1 is a schematic view of the container cross-section structure of the present application;

[0026] Figure 2 is a schematic view of the container internal structure of the present application; Figure 1 is a schematic view of the enlarged structure of A of the present application;

[0027] Figure 3 is a schematic view of the container internal structure of the present application;

[0028] Figure 4 is a schematic view of the container appearance structure of the present application. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned purpose, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification.

[0030] Many specific details are set forth in the following description in order to provide a thorough understanding of the present application. However, the present application can be practiced according to other embodiments that can not be described in detail herein, and the skilled person can make similar extensions without departing from the scope of the present application, and the present application is not limited to the specific embodiments disclosed below.

[0031] Secondly, the present application is described in detail in combination with the schematic diagram, in the detailed description of the embodiments of the present application, for the convenience of description, the sectional view of the device structure will be partially enlarged without the general proportion, and the schematic diagram is only an example, which should not limit the scope of the present application protection herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in the actual manufacture.

[0032] Thirdly, the "one embodiment" or "embodiment" referred to herein can include specific features, structures or characteristics in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not refer to the same embodiment, nor is it an embodiment that is independent of or mutually exclusive with other embodiments.

[0033] Embodiment 1

[0034] Referring to Figures 1-4 As shown in the figure, a benzylic acid static crystallization purification device, comprising a container 1, the container 1 has a feed port 11 and a discharge port 12.

[0035] The heat exchange pipeline 2 comprises an inner tube 21 and an outer tube 22, the outer tube 22 is sleeved outside the inner tube 21, and the inner tube 21 and the outer tube 22 are coaxial;

[0036] The outer wall of the inner tube 21 is thinner than the inner wall of the outer tube 22, so that there is a gap between the inner tube 21 and the outer tube 22, both ends of the gap are sealed, and water is contained in the gap;

[0037] The inner tube 21 has an inlet 211 and an outlet 212, both the inlet 211 and the outlet 212 extend from the container 1;

[0038] The outlet 212 of the inner tube 21 is connected to a liquid storage pool;

[0039] It also comprises a switching valve 3 provided with two liquid inlets and one liquid outlet;

[0040] The outlet 212 of the switching valve 3 is connected to a liquid supply pipeline 4;

[0041] The liquid supply pipeline 4 is connected to at least three liquid supply branch pipes 5 through a four-way branch joint;

[0042] The two liquid inlets of the switching valve 3 are communicated with a cold liquid supply pipeline 4 and a hot liquid supply pipeline 4 respectively.

[0043] The design has the following advantages: first, by arranging at least three heat exchange pipelines 2, the path length of the heat exchange pipelines 2 in the container 1 is reduced, the temperature difference of the cold water from the inlet 211 to the outlet 212 is reduced, the crystallization of the benzyl benzoate is more uniform, and the purity and yield of the benzyl benzoate crystallization purification are improved; second, the heat exchange pipeline 2 comprises an inner tube 21 and an outer tube 22, the inner tube 21 and the outer tube 22 have a gap therebetween, the gap is sealed at both ends, and water is contained in the gap; when the inner tube 21 passes through the cold water or the hot water, the water is first cooled or heated, so that the temperature of the outer tube 22 changes slowly and uniformly when the outer tube 22 cools or heats the benzyl benzoate; and third, by arranging the switching valve 3, the two liquid inlets of the switching valve 3 are communicated with a cold liquid supply pipeline 4 and a hot liquid supply pipeline 4 respectively, the cold water and the hot water are injected into the inner tube 21 through the liquid supply pipeline 4, so that the temperature of the inner tube 21 changes slowly, the crystallization of the benzyl benzoate is more uniform, and the purity and yield of the benzyl benzoate crystallization purification are improved.

[0044] The benzyl benzoate is crystallized by cooling when the temperature is lower than 2 degrees, and the benzyl benzoate is melted by heating when the temperature is higher than 30 degrees.

[0045] The gap is an annular gap, the distance between the inner and outer rings at each position of the gap is less than one third of the inner diameter of the inner tube 21 and greater than one fifth of the inner diameter of the inner tube 21; the specific heat capacity of the water in the gap is sufficient to prevent the temperature from changing sharply when the water exchanges heat, and the temperature change is not too slow due to too much water.

[0046] The two ends of the outer tube 22 abut against the upper and lower inner walls of the container 1, the inner tube 21, the outer tube 22 and the inner wall of the container 1 form a closed gap, and the upper and lower inner walls of the container 1 constitute the length of the gap; the upper and lower cavities of the container 1 are covered with the outer tube 22, and the heating is more uniform.

[0047] In use, first, keep the discharge port 12 closed, open the inlet port 11, and let the industrial-grade benzyl benzoate (90% < benzyl benzoate content < 95%) enter the container 1 from the inlet port 11, and then fill and stand still, switch the switch valve 3 to the cold water in the cold liquid supply pipeline 4, and let the cold water in the cold liquid supply pipeline 4, which is at a temperature < 2℃, enter the container 1 through the inlet 211 of the inner tube 21 of the heat exchange pipeline 2, and then flow out through the outlet 212 of the inner tube 21 of the heat exchange pipeline 2, about 6 hours later, the benzyl benzoate in the container 1 crystallizes under low temperature, the crystals adhere to the outer tube 22, open the benzyl benzoate discharge port 12 to discharge the uncrystallized benzyl benzoate liquid, and finally close the discharge port 12, switch the switch valve 3 to the hot liquid supply pipeline 4, and let the hot liquid supply pipeline 4 supply hot water to the inlet 211 of the inner tube 21 of the heat exchange pipeline 2, gradually heat the water in the gap, and then the temperature of the outer tube 22 rises to melt the benzyl benzoate crystals, when the water temperature is greater than 30℃, the benzyl benzoate crystals in the container 1 melt rapidly, and the liquid in the container 1 is the fine-grade benzyl benzoate with a content greater than 99.5%. Secondly, the heat exchange pipeline 2 comprises the inner tube 21 and the outer tube 22, and the inner tube 21 and the outer tube 22 have a gap therebetween, the gap is sealed at both ends, and the gap contains water, when the inner tube 21 passes through the cold water or the hot water, the water is first cooled or heated, so that the outer tube 22 is slowly and uniformly cooled or heated for the benzyl benzoate; finally, the switch valve 3 is arranged, the two liquid inlets of the switch valve 3 are communicated with a cold liquid supply pipeline 4 and a hot liquid supply pipeline 4 respectively, the cold water and the hot water are both supplied to the inner tube 21 through the liquid supply pipeline 4, so that the temperature of the inner tube 21 changes slowly, the cooling makes the benzyl benzoate crystallize more uniformly, and the purity and the yield of the benzyl benzoate crystallization and purification are improved.

[0048] Embodiment 2

[0049] Reference Figure 1 and Figure 2 As the second embodiment of the utility model, the embodiment is based on the previous embodiment.

[0050] The inner tube 21 is arranged with heat exchange fins 213, one end of the heat exchange fins 213 extends into the inner tube 21, and the other end extends into the gap surrounded by the inner tube 21, the outer tube 22 and the inner wall of the container 1; the heat exchange fins 213 can slow down the flow rate of the water in the inner tube 21, and facilitate heat exchange of the water on the inner and outer sides of the inner tube 21.

[0051] The heat exchange fins 213 are arranged in at least two rows on the inner tube 21, and the heat exchange fins 213 in the two rows are arranged in an interlaced manner; the interlaced arrangement further weakens the flow rate of the water and enables the water on the inner and outer sides of the inner tube 21 to be efficiently heat exchanged.

[0052] The outer wall of the outer tube 22 is arranged with an outwardly extending annular ring 221; the upper side of the annular ring 221 is arranged as a horizontal plane, and the lower side of the annular ring 221 is arranged as a downwardly extending inclined plane; the annular ring 221 facilitates the static crystallization of benzyl benzoate to adhere to the outer wall of the outer tube 22, preventing the crystallized benzyl benzoate from falling off and affecting the yield of benzyl benzoate.

[0053] The switching valve is further provided with two liquid outlet ports and one liquid inlet port, referred to as a water outlet valve 6; the inlet port 211 of the water outlet valve 6 is connected to a liquid outlet pipeline 7; the liquid outlet pipeline 7 is connected to at least three liquid outlet branch pipes 8 through at least a four-way branch joint, and the at least three liquid outlet branch pipes 8 are respectively communicated with the outlet ports 212 of the inner tubes 21 of the at least three heat exchange pipelines 2; the liquid storage tank is provided with two, which are a cold liquid storage tank and a hot liquid storage tank; the two liquid outlet ports of the water outlet valve 6 are respectively communicated with a cold liquid storage tank and a hot liquid storage tank. The water outlet valve 6 is synchronously switched with the switching valve 3, and after the cold water supply pipeline 4 supplies cold water, the water is injected into the cold liquid storage tank after heat exchange through the inner tube 21, and then the water in the cold liquid storage tank can be supplied to the cold water supply pipeline after refrigeration to realize cold water circulation and save energy; after the hot water supply pipeline 4 supplies hot water, the water is injected into the hot liquid storage tank after heat exchange through the inner tube 21, and then the water in the hot liquid storage tank can be supplied to the cold water supply pipeline after heating to realize cold water circulation and save energy.

[0054] The outer tube 22 is made of a copper outer tube 22 with a rough surface; the static crystallization of benzyl benzoate is facilitated to adhere to the outer wall of the outer tube 22, preventing the crystallized benzyl benzoate from falling off and affecting the yield of benzyl benzoate.

[0055] In use, the water outlet valve 6 is synchronously switched with the switching valve 3, and after the cold water supply pipeline 4 supplies cold water, the water is injected into the cold liquid storage tank after heat exchange through the inner tube 21, and then the water in the cold liquid storage tank can be supplied to the cold water supply pipeline after refrigeration to realize cold water circulation and save energy; after the hot water supply pipeline 4 supplies hot water, the water is injected into the hot liquid storage tank after heat exchange through the inner tube 21, and then the water in the hot liquid storage tank can be supplied to the cold water supply pipeline after heating to realize cold water circulation and save energy; the heat exchange fins 213 can slow down the flow rate of the water in the inner tube 21, and facilitate the heat exchange of the water on the inner and outer sides of the inner tube 21; the staggered arrangement further weakens the flow rate of the water to enable efficient heat exchange of the water on the inner and outer sides of the inner tube 21; the annular ring 221 and the rough surface facilitate the static crystallization of benzyl benzoate to adhere to the outer wall of the outer tube 22, preventing the crystallized benzyl benzoate from falling off and affecting the yield of benzyl benzoate.

[0056] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual implementations can be described, nor are those features related to the best mode of carrying out the present application currently under consideration, or those features related to the implementation of the present application.

[0057] It is to be understood that the development process can involve both substantial design and experimental efforts. As such, in embodiments of the application, design synthesis and / or experimental tests can be conducted to help improve the performance of the devices. Efforts can be directed to concurrently improving one or more performance characteristics of the devices.

[0058] It should be noted that the above examples are only used to illustrate the technical solutions of the present application but not limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced without departing from the spirit and scope of the present application, and all modifications and equivalent replacements should be included in the scope of the claims of the present application.

Claims

1. A static crystallization purification apparatus for benzyl benzoate, comprising a container having an inlet and an outlet, characterized in that: At least three heat exchange pipes are arranged in the container; The heat exchange pipe includes an inner pipe and an outer pipe, with the outer pipe sleeved outside the inner pipe and the inner and outer pipes coaxial. The outer wall of the inner tube is thinner than the inner wall of the outer tube, creating a gap between the inner and outer tubes. The two ends of the gap are sealed, and water is placed in the gap. The inner tube has an inlet and an outlet, both of which extend from the container; The outlet of the inner tube is connected to the liquid storage tank; It also includes a switching valve with two inlets and one outlet; The outlet of the switching valve is connected to a liquid supply pipeline; The liquid supply pipeline is connected to at least three liquid supply branch pipes through at least four-way branch pipe joints, and the at least three liquid supply branch pipes are respectively connected to the inlet of the inner pipe of at least three heat exchange pipelines; The two inlets of the switching valve are connected to a cold liquid supply pipeline and a hot liquid supply pipeline, respectively.

2. The static crystallization purification apparatus for benzyl benzoate according to claim 1, characterized in that: The inner tube is provided with heat exchange fins, one end of which extends into the inner tube and the other end extends into the gap.

3. The static crystallization purification apparatus for benzyl benzoate according to claim 2, characterized in that: The heat exchange fins are arranged in at least two rows on the inner tube, and the two rows of heat exchange fins are arranged in an alternating manner.

4. The static crystallization purification apparatus for benzyl benzoate according to claim 1, characterized in that: The outer wall of the outer tube is provided with outwardly extending rings; The upper side of the ring is set as a horizontal plane, and the lower side of the ring is set as a downwardly extending slope.

5. The static crystallization purification apparatus for benzyl benzoate according to claim 1, characterized in that: The gap is an annular gap, and the distance between the inner and outer rings at each point of the gap is less than one-third of the inner diameter of the inner tube and greater than one-fifth of the inner diameter of the inner tube.

6. The static crystallization purification apparatus for benzyl benzoate according to claim 1, characterized in that: The two ends of the outer tube abut against the upper and lower inner walls of the container, and the inner tube, outer tube and inner wall of the container form a sealed gap, with the upper and lower inner walls of the container constituting the length of the gap.

7. The static crystallization purification apparatus for benzyl benzoate according to claim 1, characterized in that: It also includes another switching valve with two outlets and one inlet, called the water outlet valve; The inlet of the outlet valve is connected to an outlet pipe; The liquid outlet pipe is connected to at least three liquid outlet branch pipes through at least four-way pipe joints, and the at least three liquid outlet branch pipes are respectively connected to the outlet of the inner pipe of at least three heat exchange pipes. There are two liquid storage tanks, namely a cold liquid storage tank and a hot liquid storage tank; The two outlets of the water outlet valve are connected to a cold storage tank and a hot storage tank, respectively.

8. The static crystallization purification apparatus for benzyl benzoate according to claim 1, characterized in that: The outer tube is made of copper with a rough surface.

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