Internal pressure reducing system of PTA (pure terephthalic acid) drying machine

Abstract

The utility model discloses a PTA dryer internal pressure reducing system which comprises a washing tower body, a cooler is fixedly connected to the inner surface of the washing tower body, a spray washing tower system is fixedly connected to the inner surface of the washing tower body, and the spray washing tower system comprises a washing tower circulating pump, a water pump, a water pump, a water pump and a water pump. The output end of the washing tower circulating pump is fixedly connected with a spraying head, the side surface of the washing tower body is fixedly connected with a filler washing circulating pump, and the output end of the filler washing circulating pump is fixedly connected with the spraying head; the side surface of the washing tower body is fixedly connected with a drying system, by additionally arranging a spraying washing tower system and a spiral pushing device, water vapor and powder carried out by non-condensable gas in a drying machine are pushed, and the situation that the water vapor and the powder are accumulated in a gas phase pipeline for a long time to cause blockage and influence smoothness is avoided; the problems that internal pressure of a traditional drying machine system is continuously high, and powder leakage of a drying machine is serious are effectively solved.

Description

Technical Field

[0001] The utility model relates to the technical field of PTA production devices, in particular to a system for reducing the internal pressure of a PTA dryer. Background Art

[0002] During the PTA production process, the crystallized slurry is filtered through a filtration system to separate the solid-liquid mixture into a liquid filter cake and a mother liquor. The filter cake enters the drying system, where the water in it is heated. The water is converted into a gaseous state after heating and then carried out of the system by non-condensable gas (usually nitrogen), thereby separating the water from the wet filter cake and obtaining a dried finished powder.

[0003] During production operation, the water in the wet filter cake evaporates after heating, and the water vapor is carried out of the system through the action of non-condensable gas, causing the volume of the drying system to expand and the pressure to rise. When the pressure rises to a certain level, it is very easy to cause powder leakage in the dryer, causing environmental pollution and affecting the long-term safe and stable operation of the device. The traditional solution is to use a fan to extract it and dispose of it in the exhaust gas treatment facility. This not only increases the production and construction costs of the relevant exhaust treatment system, but also increases the operating costs, and its applicability is relatively limited. Utility Model Content

[0004] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a system for reducing the internal pressure of a PTA dryer. The device adopts an additional spray washing tower system and a spiral pusher to push the water vapor and powder carried out from the non-condensable gas inside the dryer, thereby avoiding the situation where the water vapor and powder are accumulated for a long time in the gas phase pipeline and cause blockage and affect the smooth flow. It effectively solves the problem of the traditional dryer system with continuously high internal pressure, serious powder leakage in the dryer, shortened operation cycle, and increased maintenance frequency and cost.

[0005] The utility model also provides a PTA dryer internal pressure reducing system, comprising: a washing tower body, an inner surface of the washing tower body being fixedly connected to a cooler, an inner surface of the washing tower body being fixedly connected to a spray washing tower system, the spray washing tower system comprising: a washing tower circulation pump, an output end of the washing tower circulation pump being fixedly connected to a spray head, a side surface of the washing tower body being fixedly connected to a packing washing circulation pump, the output end of the packing washing circulation pump being fixedly connected to the spray head; through the mutual cooperation between the above-mentioned parts, water vapor and powder carried out from the non-condensable gas inside the dryer are pushed out, thereby avoiding the situation where the water vapor and powder are accumulated in the gas phase pipeline for a long time and cause blockage and affect the smooth flow.

[0006] The side surface of the scrubber body is fixedly connected to a drying system. This system comprises a dryer body, a feed screw fixedly connected to the side surface of the dryer body, a discharge chimney fixedly connected to the bottom surface of the scrubber body, and a screw pusher fixedly connected to the side surface of the discharge chimney. The interaction between these components effectively solves the problem of traditional dryer systems with persistently high internal pressure, serious powder leakage, reduced operating cycles, and increased maintenance frequency and costs.

[0007] According to the PTA dryer internal pressure reduction system of the present invention, a second packing layer is fixedly connected to the inner surface of the scrubbing tower body, and a first packing layer is fixedly connected to the upper surface of the second packing layer. The interaction between these components facilitates sufficient contact between the top fresh production water and the packing surface.

[0008] According to the PTA dryer internal pressure reduction system described in the utility model, a pressure indicator is fixedly connected to the lower surface of the second packing layer, and both the first and second packing layers utilize rectangular saddle-shaped packing. The interaction between these components facilitates determining whether non-condensable gas is clogged in a specific area based on pressure changes, allowing for targeted treatment.

[0009] According to the PTA dryer internal pressure reduction system described in the utility model, the output end of the cooler is provided with a non-condensable gas cooling gas, and the side surface of the scrubber body is provided with cooling water inlet and cooling water return. Through the interaction between these components, the water vapor in the non-condensable gas is condensed by cooling the cooling water, and the gas phase volume is reduced.

[0010] The PTA dryer internal pressure reduction system of the present invention comprises a split scrubber body with two upper and lower layers, and a production water circulation system on the inner surface of the scrubber body. The interaction between these components facilitates the upward movement of non-condensable gas, which, as it passes through the packing layer, forms a counter-washing reaction with the production water above.

[0011] According to the PTA dryer internal pressure reduction system of the present invention, a filter system is fixedly connected to the upper surface of the feed screw, and the upper surface of the filter system is fixedly connected to one end of the discharge chimney. The interaction between these components facilitates the separation of filter cake and mother liquor.

[0012] According to the PTA dryer internal pressure reduction system of the present invention, the inner surface of the dryer body is fixedly connected to the dryer cylinder, and the lower surface of the dryer body is provided with a discharge port. The mutual cooperation between the above parts facilitates discharge.

[0013] The PTA dryer internal pressure reduction system of the present invention comprises a heat exchanger fixedly connected to the side surface of the dryer cylinder, which is made of stainless steel. The interaction between these components facilitates the upward flow of non-condensable gas through the heat exchanger, cooling the water vapor and thereby reducing the internal pressure.

[0014] Beneficial effects

[0015] Compared with the existing technology, the utility model adopts an additional spray washing tower system and a spiral pusher to push the water vapor and powder carried out from the non-condensable gas inside the dryer, thereby avoiding the long-term accumulation in the gas phase pipeline causing blockage and affecting the smooth flow. It effectively solves the problem of the traditional dryer system with continuously high internal pressure, serious powder leakage in the dryer, shortened operating cycle, and increased maintenance frequency and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0017] Figure 1 This is the overall flow chart of the system for reducing the internal pressure of the PTA dryer of the utility model;

[0018] Legend:

[0019] 1. First packing layer; 2. Second packing layer; 3. Pressure indicator; 4. Discharge chimney; 5. Feed screw; 6. Dryer body; 7. Non-condensable gas cooling air; 8. Packing washing circulation pump; 9. Washing tower circulation pump; 10. Discharge port; 11. Screw pusher; 12. Spray head; 13. Washing tower body; 14. Cooler; 15. Filtration system; 16. Drying system; 17. Dryer cylinder; 18. Heat exchanger. DETAILED DESCRIPTION

[0020] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0021] Reference Figure 1, The utility model embodiment is a PTA dryer internal pressure reduction system, which includes: a washing tower body 13, the washing tower body 13 adopts a split upper and lower two-layer structure, the inner surface of the washing tower body 13 is provided with an internal circulation of production water, so that the non-condensable gas continues to move upward and forms a reverse washing with the production water above when passing through the packing layer, the inner surface of the washing tower body 13 is fixedly connected with the second packing layer 2, the lower surface of the second packing layer 2 is fixedly connected with the pressure display 3, the first packing layer 1 and the second packing layer 2 both adopt rectangular saddle type packing, which is convenient for judging whether the non-condensable gas of each section is blocked in a certain area according to the pressure change, so as to deal with it in a targeted manner, the upper surface of the second packing layer 2 is fixedly connected with the first packing layer 1, so as to fully contact with the fresh production water at the top on the packing surface, and the washing The inner surface of the tower body 13 is fixedly connected to a cooler 14, and the output end of the cooler 14 is provided with a non-condensable gas cooling gas 7. The side surface of the washing tower body 13 is provided with cooling water inlet and cooling return water. The water vapor in the non-condensable gas is condensed by cooling with the cooling water, and the gas phase volume shrinks. The inner surface of the washing tower body 13 is fixedly connected to a spray washing tower system. The spray washing tower system includes: a washing tower circulation pump 9, and the output end of the washing tower circulation pump 9 is fixedly connected to a spray head 12. The side surface of the washing tower body 13 is fixedly connected to a packing washing circulation pump 8, and the output end of the packing washing circulation pump 8 is fixedly connected to the spray head 12 to push the water vapor and powder carried out by the non-condensable gas inside the dryer, thereby avoiding the situation where the water vapor and powder are accumulated in the gas phase pipeline for a long time and cause blockage and affect the smooth flow.

[0022] A drying system 16 is fixedly connected to the side surface of the washing tower body 13. The drying system 16 includes: a dryer body 6, a dryer cylinder 17 fixedly connected to the inner surface of the dryer body 6, and a heat exchanger 18 fixedly connected to the side surface of the dryer cylinder 17. The dryer cylinder 17 is made of stainless steel to facilitate the non-condensable gas to continue to pass upward through the heat exchanger 18 to cool the water vapor, thereby reducing the internal pressure. A discharge port 10 is opened on the lower surface of the dryer body 6 to facilitate discharge. A feed screw 5 is fixedly connected to the side surface of the dryer body 6, and a filter system 15 is fixedly connected to the upper surface of the feed screw 5. The upper surface of the filter system 15 is fixedly connected to one end of the discharge chimney 4 to facilitate separation to form filter cake and mother liquor. The lower surface of the washing tower body 13 is fixedly connected to the discharge chimney 4, and the side surface of the discharge chimney 4 is fixedly connected to the screw pusher 11. This effectively solves the problems of traditional dryer systems with continuously high internal pressure, serious powder leakage in the dryer, shortened operating cycle, and increased maintenance frequency and cost.

[0023] Working principle: When using this device, first, the material inside the dryer body 6 is heated by steam to form water vapor, and the non-condensable gas is introduced from the discharge port 10 side of the dryer body 6 using nitrogen. Nitrogen is used as the power source for the upward movement of water vapor. Nitrogen passes through the feed screw 5 of the dryer body 6 and enters the discharge chimney 4. Then it enters the screw pusher 11 through the chimney. A spray head 12 is designed on the upper part of the spiral to initially spray the water vapor and powder carried by the nitrogen to prevent the spiral belt and the cylinder from forming a wall and avoid resistance. The non-condensable gas and water vapor enter the washing In the tower body 13, the powder is removed after being sprayed by the tower bottom washing tower circulating pump 9 to avoid entering the upper cooler 14. After the non-condensable gas after being washed enters the cooler 14, it is cooled by the cooling water to condense the water vapor in the non-condensable gas, and the gas phase volume shrinks. The non-condensable gas continues to rise and enter the first packing layer 1. The washing liquid collected through the second packing layer 2 at the bottom is used as a spray. The non-condensable gas continues to rise, passes through the upper first packing layer 1, and fully contacts with the fresh production water on the packing surface at the top. After washing, it is emptied. Then the slurry after flash crystallization enters The filter system 15 forms filter cake and mother liquor after separation. The filter cake enters the drying system 16, and the mother liquor enters other systems for disposal. The filter cake falls into the chimney of the drying system 16. The bottom of the chimney is the feed screw 5 of the dryer body 6, which pushes the wet filter cake into the dryer cylinder 17. The non-condensable gas (nitrogen) at the discharge port 10 end of the dryer body 6 enters the cylinder and carries water vapor and powder into the dryer chimney. Here, it is sprayed by the washing tower bottom pump and then pushed to the washing tower body 13 by the screw pusher 11. The washing tower bottom pump is equipped with an annular spray. The non-condensable gas after spraying Most of the powder in the gas falls to the bottom of the tower and is transported to the batching tank for pulping. The non-condensable gas continues to move upward through the heat exchanger 18 to cool the water vapor, thereby reducing the internal pressure. The cooled non-condensable gas continues to move upward and is sprayed with system process water to continue cooling, converting all the water vapor into a liquid state. The non-condensable gas continues to move upward and forms a reverse washing with the production water above when passing through the packing layer, ensuring that there are no dust particles and reducing the non-methane total hydrocarbon content in the system. By monitoring each pressure, it is determined according to the pressure change whether each section of non-condensable gas is blocked in a certain area, so as to deal with it in a targeted manner.

[0024] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A PTA dryer internal pressure reduction system, characterized in that: include: A washing tower body (13), the inner surface of which is fixedly connected to a cooler (14), the inner surface of which is fixedly connected to a spray washing tower system, the spray washing tower system comprising: a washing tower circulation pump (9), the output end of which is fixedly connected to a spray head (12), a side surface of which is fixedly connected to a packing washing circulation pump (8), the output end of which is fixedly connected to the spray head (12); The side surface of the washing tower body (13) is fixedly connected to a drying system (16), and the drying system (16) includes: a dryer body (6), the side surface of the dryer body (6) is fixedly connected to a feeding screw (5), the lower surface of the washing tower body (13) is fixedly connected to a discharge chimney (4), and the side surface of the discharge chimney (4) is fixedly connected to a screw pusher (11).

2. The PTA dryer internal pressure reducing system according to claim 1, characterized in that: The inner surface of the washing tower body (13) is fixedly connected to a second packing layer (2), and the upper surface of the second packing layer (2) is fixedly connected to a first packing layer (1).

3. A PTA dryer internal pressure reducing system according to claim 2, characterized in that: A pressure display (3) is fixedly connected to the lower surface of the second packing layer (2), and both the first packing layer (1) and the second packing layer (2) use rectangular saddle type packing.

4. The PTA dryer internal pressure reducing system according to claim 1, characterized in that: The output end of the cooler (14) is provided with non-condensable gas cooling air (7), and the side surface of the washing tower body (13) is provided with cooling inlet water and cooling return water.

5. The PTA dryer internal pressure reducing system according to claim 1, characterized in that: The washing tower body (13) adopts a split upper and lower two-layer structure, and the inner surface of the washing tower body (13) is provided with an inner circulation of production water.

6. The PTA dryer internal pressure reducing system according to claim 1, characterized in that: The upper surface of the feeding screw (5) is fixedly connected to a filtering system (15), and the upper surface of the filtering system (15) is fixedly connected to one end of the discharge chimney (4).

7. The PTA dryer internal pressure reducing system according to claim 1, characterized in that: A dryer barrel (17) is fixedly connected to the inner surface of the dryer body (6), and a discharge port (10) is provided on the lower surface of the dryer body (6).

8. The PTA dryer internal pressure reducing system according to claim 7, characterized in that: A heat exchanger (18) is fixedly connected to the side surface of the dryer cylinder (17), and the material of the dryer cylinder (17) is stainless steel.

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