WO2021244193A1

WO2021244193A1 - System for producing pbs-based biodegradable material

Info

Publication number: WO2021244193A1
Application number: PCT/CN2021/090468
Authority: WO
Inventors: 王有超; 陶家宏
Original assignee: 欧瑞康巴马格惠通（扬州）工程有限公司
Priority date: 2020-06-01
Filing date: 2021-04-28
Publication date: 2021-12-09
Also published as: CN111530361A

Abstract

Disclosed is a system for producing a PBS-based biodegradable material, the system comprising esterification reaction kettles. The esterification reaction kettles include esterification kettle A (3a), esterification kettle B (3b) and a second esterification kettle (4). A slurry inlet at the top of esterification kettle A (3a) is connected to a discharge port of slurry formulation tank I (2a), a top inlet of slurry formulation tank I (2a) is connected to a discharge port of slurry compounding tank I (1a), and the top of slurry compounding tank I (1a) is connected to a BDO feed pipe (G0) and is provided with a PTA charging port (1a1). A slurry inlet at the top of esterification kettle B (3b) is connected to a discharge port of slurry formulation tank II (2b), a top inlet of slurry formulation tank II (2b) is connected to a discharge port of slurry compounding tank II (1b), and the top of slurry compounding tank II (1b) is connected to a BDO feed pipe (G0) and is provided with a binary acid charging port (1b1). A discharge port of esterification kettle A (3a) and a discharge port of esterification kettle B (3b) are respectively connected to a feeding port of the second esterification kettle (4); a discharge port of the second esterification kettle (4) is connected to a feeding port of a first condensation kettle (5) via an esterification material pump (B1); a discharge port of the first condensation kettle (5) is connected to a feeding port of a second condensation kettle (6) via a first condensation material pump (B2); a discharge port of the second condensation kettle (6) is connected to a feeding port of a final condensation reaction kettle (7) via a second condensation material pump (B3); and a discharge port of the final condensation reaction kettle (7) is connected to a feeding port of a tackifying reaction kettle (8) via a melt delivery pump (B4).

Description

PBS-type biodegradable material production system

Technical field

The invention relates to a production system for polyester chips, in particular to a production system for PBS-type biodegradable materials, and belongs to the technical field of polyester chip production equipment.

Background technique

With the progress of society and the improvement of environmental protection requirements, the production of PBS biodegradable materials has been more and more widely used. PBS includes PBS (polybutylene succinate), PBAT (polyterephthalate) Butylene adipate), PBST (polybutylene succinate-co-butylene terephthalate) and PBSA (butylene succinate-butylene adipate copolymer) )Wait.

The production of PBS requires the use of 1,4 butanediol (BDO), terephthalic acid (PTA) and dibasic acid, etc. The dibasic acid includes adipic acid, sebacic acid or succinic acid, etc. The existing technology Among them, terephthalic acid, dibasic acid, and 1,4-butanediol are beaten in a certain proportion, and then sent to the first esterification reactor for reaction. After the reaction, they are sent to the second esterification tank for further reaction, and then pass through the first After polycondensation, second polycondensation, final polycondensation, and viscosity increase, the traditional PBS production system has the following defects:

1. Terephthalic acid (PTA), dibasic acids such as adipic acid, 1,4-butanediol (BDO) are reacted in the same esterification reactor. To ensure the reaction of PTA and BDO, the esterification temperature is as high as 230 ~250°C, causing serious side reactions of 1,4-butanediol, high raw material consumption, large production of tetrahydrofuran (THF), increased pressure in the tetrahydrofuran treatment device, and poor product quality.

2. PBS slices are usually dehydrated by a centrifugal separator or a vacuum drum machine, which can only remove the moisture on the surface of the PBS slices, so that the moisture content of the PBS slices entering the intermediate bin is still relatively high. If the packaging is directly used, it is easy to cause degradation. At the same time, a certain amount of tetrahydrofuran in the slices is easy to be gradually released after a period of time. There are batch differences between the produced materials, which cannot achieve uniformity, which affects the use level of the product.

3. The mixture of BDO, water and a little oligomer from the gas phase outlet of the first polycondensation kettle, the second polycondensation kettle, the final polycondensation reactor and the viscosity-increasing reactor enters the scraper condenser, which is sprayed and captured by the scraper condenser. Under the cooling of the spray liquid, most of the gas becomes liquid, and a small amount of non-condensable gas is pumped away by the rear vacuum unit. A few oligomers fall on the bottom of the scraper under the action of gravity and scraping by the scraper. Finally, the oligomer particles and BDO fall into the hot well together through the atmospheric leg, causing blockage of the hot well or damage to the scraper during the scraper wall hanging process, causing the scraper condenser to stop working, and the oligomer in the hot well needs to be discharged into the slag regularly The box is cleaned.

4. In the actual production process, the atmospheric leg may also be blocked, causing the spray to fail to operate normally, causing vacuum fluctuations or loss of vacuum, and it has to be shut down in severe cases. Long processing time and huge production losses often occur. The traditional slag discharge box is mostly vertical and flat, which is difficult to open and clean, or has a square shape. The sealing surface is too large and the sealing is difficult; the filter is easy to block, causing the filtrate to overflow directly to the discharge port with the slag. The drain port is blocked; there is too much slag trapped on the top filter screen, and the rapid stacking will quickly cause the feed port of the slag box to be blocked.

Summary of the invention

The purpose of the present invention is to overcome the problems existing in the prior art and provide a PBS-type biodegradable material production system that can produce PBS, PBAT, PBST and PBSA, etc., which can greatly reduce BDO consumption and reduce side effects. The reaction and the amount of tetrahydrofuran produced.

In order to solve the above technical problems, a PBS-type biodegradable material production system of the present invention includes an esterification reaction kettle, and the esterification reaction kettle includes an esterification kettle A, an esterification kettle B, and a second esterification kettle, The slurry inlet on the top of the esterification kettle is connected to the discharge port of slurry configuration tank 1, the top entrance of slurry configuration tank 1 is connected to the discharge port of slurry preparation tank 1, and the top of slurry preparation tank 1 is connected to the BDO The feed pipe is connected with a PTA feeding port; the slurry inlet on the top of the esterification kettle B is connected with the outlet of the slurry configuration tank two, and the top inlet of the slurry configuration tank two is connected with the discharge port of the slurry mixing tank two Connected, the top of the slurry mixing tank two is connected with the BDO feed pipe and is provided with a dibasic acid feed port; the outlets of the A esterification kettle and the B esterification kettle are respectively the inlets of the second esterification kettle Connected, the outlet of the second esterification kettle is connected to the inlet of the first polycondensation kettle through the esterification material pump, the outlet of the first polycondensation kettle is connected to the feed of the second polycondensation kettle through the first polycondensation material pump B2 The outlet of the second polycondensation kettle is connected to the inlet of the final polycondensation reactor through the second polycondensation material pump, and the outlet of the final polycondensation reactor is connected to the inlet of the viscosity-increasing reactor through the melt transfer pump Connected.

Compared with the prior art, the present invention has achieved the following beneficial effects: BDO and PTA are mixed in batches in slurry preparation tank 1 according to a certain molar ratio, and are sent to slurry configuration tank 1 after being fully stirred and evenly mixed, and then from the slurry configuration tank 1. Enter the esterification kettle A for esterification reaction; BDO and adipic acid, sebacic acid, succinic acid or other dibasic acid are mixed in batches in slurry preparation tank 2 according to a certain molar ratio, and they are fully stirred and sent into Slurry configuration tank two, then enters the B esterification kettle from the slurry configuration tank two to carry out the esterification reaction. Since the reaction temperature of dibasic acid such as adipic acid and BDO is 170-210℃, the reaction temperature of PTA and BDO is 230～250℃. According to the temperature and pressure required for their reaction, the esterification reaction can be carried out separately. The consumption of BDO is greatly reduced, the production of tetrahydrofuran is reduced, and the quality of the material can be precisely controlled. The esterified ester of B and the esterified ester of A are respectively sent to the second esterification tank for mixed esterification, the mixed esterification material enters the first polycondensation tank for pre-polycondensation, and the pre-condensation material enters the second polycondensation tank for pre-condensation. Recondensation, the recondensation material enters the final polycondensation reactor for final polycondensation, and the final polycondensation material enters the viscosity-increasing reactor to increase the viscosity. The reaction between A esterification kettle and B esterification kettle under different process conditions can reduce the side reaction of BDO, reduce the consumption of raw materials and the amount of tetrahydrofuran produced, and improve the quality of products.

As an improvement of the present invention, the discharge port of the viscosity increasing reactor is connected to the pelletizer through the melt booster pump one; the outlet of the melt transfer pump is connected to the melt heat exchanger through the melt metering pump. The inlet is connected, the outlet of the melt heat exchanger and the outlet of the chain extender adding system are connected to the inlet of the second melt booster pump, and the outlet of the second melt booster pump is connected to the second pelletizer . On route one, the thickened melt through the thickening reactor will be sent to the pelletizer by the melt booster pump to cut pellets, which can meet the needs of most customers, including the requirements of food-grade products. In route two, after the final polycondensation material is sent out by the melt transfer pump, it is first measured by the melt metering pump, then the temperature is adjusted by the melt heat exchanger, and then enters the melt together with the modified material from the chain extender addition system The second booster pump is fed from the second melt booster pump to the second pelletizer, which can realize the online modification of some products. The melt line is short, the residence time is short, it is not easy to thermally decompose, and the product quality is good; at the same time, the system With good compatibility, products with different characteristics can be produced to satisfy different downstream customers.

As a further improvement of the present invention, the outlets of the first pelletizer and the second pelletizer are respectively connected to the respective middle slicing silo. The outlet of the discharge valve of the silo is respectively connected to the chip inlet on the top of the chip drying tower through the air supply pipe 1, and the chip outlet at the bottom of each chip drying tower is connected to the inlet of the discharge valve of the drying tower. The outlet of the tower discharge valve is connected to the slice feed port on the top of the slice drying tower two through the second air supply pipe, and the slice discharge port at the bottom of each slice drying tower two is connected to the main feed port of the mixing silo. The outlets of the silo are respectively connected with the vacuum packaging machine. The PBS-type slices in the slicing intermediate silo are discharged through the discharge valve of the intermediate silo, and enter the slice drying tower 1 under the conveyance of the air conveying pipe 1. Evaporation, the preliminarily dried slices are discharged from the discharge valve of the drying tower, and enter the slice drying tower 2 under the air conveying pipe 2. The slices and the hot air continue to exchange heat and moisture in the slice drying tower 2, and the remaining water and tetrahydrofuran are evaporated After that, it enters the mixed silo from the main feed port for temporary storage, and then enters the vacuum packaging machine for packaging. Due to the two-stage series evaporation, the water and tetrahydrofuran in the PBS-type slices are removed, and the vacuum packaging is adopted, and the product will not be degraded after being placed for a period of time. The quality of the product has increased by one level, which can meet the requirements of food-grade use.

As a further improvement of the present invention, the hot air outlets at the top of the chip drying tower 1 and the chip drying tower 2 are connected to the air inlet of the dust collector through a dust removal suction pipe, and the top air outlet of the dust collector is connected to the air through a return air duct. The air supply port of the third air supply pipe is connected, the feed port of the third air supply pipe is connected with the outlet of the slice batching valve, the inlet of the slice batching valve is connected with the outlet of the slice batching hopper, and the outlet of the third air supply pipe is connected with The auxiliary feed inlets of the mixed silo are connected. The hot air after moisture absorption is discharged from the hot air outlet at the top of the slice drying tower 1 and the top of the slice drying tower 2, and enters the dust collector through the dust removal suction pipe. The dust in the slice is intercepted by the dust collector, and the clean exhaust gas enters the air through the return air duct. The air supply outlet of the third pipe is recycled. Slices with different molecular weights have different viscosities. The auxiliary materials are temporarily stored in the slice batching hopper, discharged from the slice batching valve, and enter the mixing silo from the auxiliary feed port under the air conveying pipe three, and enter the freshly dried slices from the main feed port. Evenly mix in proportion and change the mixing ratio. The mixed slices can be extruded to obtain melts with different viscosities. The product has a wider range of applications. At the same time, the waste heat and nitrogen in the clean exhaust gas are recovered, which greatly reduces the consumption of heat and materials. .

As a further improvement of the present invention, the main feed inlet is located at the center of the top of the mixed silo, the auxiliary feed inlets are located symmetrically on both sides of the main feed inlet, and the inner cavity of the mixed silo is at least There are three mixing chute, each mixing chute extends vertically and is symmetrically distributed around the axis of the mixing silo. The height direction of the chute is evenly provided with a plurality of chute sections, and each chute section is respectively provided with a chute, and each chute is spirally distributed along the circumference of the mixing chute. The main feed port and the auxiliary feed port feed at the same time and fall above the material layer at the same time to achieve static mixing in each section of the mixing silo. The slices in the central area of the mixing silo flow out from the bottom outlet of the mixing silo in turn. Achieve first-in, first-out; part of the slices in the surrounding area of the mixing silo enter the inner cavity of the mixing chute from each chute, and quickly descend along the mixing chute and fall into the cone of the mixing silo, realizing the backward entry of some slices First out, dynamic mixing is realized in the height direction of the mixing silo. The first-in first-out static mixing and the last-in first-out dynamic mixing work together. The slices arranged in the slice drying tower and the slice batching hopper are uniformly arranged in the mixing silo Mixing greatly improves the uniformity and quality of mixed slices. The mixing chute is distributed symmetrically in the center, and the chute on the mixing chute is evenly distributed in the height direction and the circumferential direction, which can further improve the uniformity of the slice mixing.

As a further improvement of the present invention, the slice drying tower one and the slice drying tower two respectively include a vertical cylindrical tower body, the top center of the tower body is provided with the slice feed inlet, and the tower body hot air outlet Located on one side of the slice feed port; the lower part of the tower body is provided with the tower body hot air inlet, the bottom of the tower body is connected with a drying tower cone, and the slice discharge port is located in the drying tower At the lower end of the cone, along the axis of the tower, there are a plurality of right-cone-shaped material distributing umbrella caps. Except for the top material distributing umbrella cap, the upper part of each material distributing umbrella cap and the bottom of the bottom material distributing umbrella cap are respectively set There are baffles coaxial with the baffles, and each baffle is in the shape of a bell mouth with a large top and a small bottom. PBS type slices enter the inner cavity of the tower from the slice feed port on the top, and first fall on the outer cone of the top layer of the distributing umbrella cap, splashed and evenly scattered around, and then fall downwards on the inner cone of the baffle Then, it splashes toward the center and falls from the center hole of the baffle, and falls on the outer cone of the distributing umbrella cap of the next layer; hot nitrogen or hot air enters from the lower part of the tower, and it is sliced with PBS in the upward direction. It is heated during the reverse flow process. In this way, in the process of turning back and flying downwards for many times of PBS type slices, the water or THF is gradually removed, and finally the slices fall into the drying tower cone and are discharged from the slice discharge port at the bottom of the tower, and the hot air is discharged from the hot air outlet of the tower body at the top of the tower. discharge.

As a further improvement of the present invention, the upper end of each baffle plate is connected to the inner wall of the tower body, each baffle plate has a thin-walled cavity structure, and the lower wall of each baffle plate passes through a plurality of evenly distributed lower walls. The radial connecting pipe is connected with the corresponding baffle air supply ring pipe, and each baffle air supply ring pipe surrounds the outer circumference of the tower body and is respectively provided with a baffle hot air interface, and the upper wall of each baffle is uniform There are multiple baffle hot air holes; the nitrogen pipe is connected to the air inlet of the gas heater, and the air outlet of the gas heater is connected to the hot air main pipe. The hot air main pipe is connected to the hot air branch pipes of each layer. The cold air branch pipes of each layer are connected with the baffle air supply pipe of the layer, and the outlets of the baffle air supply pipes of each layer are respectively connected with the baffle hot air interface of the layer. Hot nitrogen or hot air enters the inner cavity of each baffle from the baffle air supply ring pipe along each radial connecting pipe, and sprays upward from the hot air holes of the baffle on the wall of the baffle, and the slices fall on the baffle At the same time on the board, it is dried and stirred by the hot air from the hot air holes of the baffle, which further improves the drying effect and uniformity. After the nitrogen is heated by the gas heater, it enters the hot air main pipe, and the temperature is measured by the hot air temperature sensor. If the temperature of the hot air is low, increase the opening of the heating control valve; if the temperature of the hot air is high, reduce the heat supply Adjust the opening of the valve. Then the hot air enters the hot air branch pipes of each layer, mixes with the cold air from the cold air branch pipes of the same layer, enters the baffle air supply pipe of the layer, and then enters the baffle plate of the layer through the baffle air supply loop pipe. When the temperature detected by the air supply temperature sensor of a certain layer of baffle is low, turn off the cold air regulating valve of this layer; otherwise, open the cold air regulating valve of this layer. In this way, through the multi-layer and independent temperature control system, according to the control process requirements of the drying tower, different temperatures are controlled in stages to achieve high-efficiency removal of water and tetrahydrofuran.

As a further improvement of the present invention, the diameter of the upper end of the drying tower cone is larger than the diameter of the tower body, and the lower end of the tower body is inserted into the upper port of the drying tower cone, and the diameter of the drying tower cone is The upper port is provided with an annular cover, and the inner edge of the annular cover is welded to the outer wall of the tower body; the annular cavity under the annular cover is connected to the tower body through a plurality of evenly distributed radial communication pipes The air supply ring pipe is connected, the tower body hot air inlet is provided on the circumference of the tower body air supply ring pipe, and a downward opening is provided between the lower port of the tower body and the inner wall of the drying tower cone. Annular hot air passage. The hot air enters the annular cavity at the upper end of the drying tower cone from the air supply ring pipe of the tower body along the radial connecting pipes, and blows downward from the annular hot air passage between the tower body and the drying tower cone. The bucket is in a state of flowing downwards along the circumferential wall first, and then upwards along the central area. The slices falling into the cone of the drying tower are heated and loosened to prevent sticking to the wall, mutual adhesion and blockage.

As a further improvement of the present invention, the gas phase outlets of the first polycondensation kettle, the second polycondensation kettle, the final polycondensation reaction kettle or the viscosity-increasing reaction kettle are respectively connected to the side wall inlets of the respective vacuum traps, and the top of each vacuum trap The gas-phase ports are respectively connected with the air inlets of the scraper condensers, the bottom outlets of the vacuum traps are respectively connected to the top inlets of the vacuum collection tanks through electric shut-off valves, and the top air inlets of the vacuum collection tanks also pass through the collection tank nitrogen valve Connected to the nitrogen pipe, the bottom of each vacuum collection tank is equipped with a collection tank discharge valve; the medium outlet of each scraper condenser is connected to the respective hot well through the atmospheric leg, and the liquid phase outlet of each hot well is connected to the spray circulation pump The inlet of the spray circulating pump is connected with the spray outlet of the scraper condenser through a circulating liquid cooler. After the mixture of BDO, water and oligomer is discharged from the gas-phase port of each polycondensation kettle or thickening kettle, it first enters the vacuum trap. Due to the reduced gas velocity, under the action of gravity, the liquid oligomer is in the vacuum trap. BDO, water and a small amount of oligomers enter the scraper condenser to be sprayed and collected. The condensed oligomers are discharged from the medium outlet of the scraper condenser along with the BDO, and enter the hot well through the atmospheric leg to be filtered and sprayed. The liquid BDO is pumped out by the spray circulating pump, cooled by the circulating liquid cooler, and returned to the spray port of the scraper condenser for circulating spray. When a certain level gauge is accumulated in the vacuum trap, the electric shut-off valve is turned on, the nitrogen in the vacuum trap enters the vacuum trap and is discharged from its gas phase port, and the liquid oligomer enters the vacuum trap to be stored until it reaches a certain level. After measuring, open the collection tank nitrogen valve of the vacuum collection tank, and fill the vacuum collection tank with nitrogen. At the same time, open the collection tank discharge valve at the bottom of the vacuum collection tank to discharge the liquid oligomer into the collection tank. After that, continue to pour in nitrogen for about 10 seconds to seal the vacuum collection tank, and then close the collection tank's nitrogen valve. Since most of the oligomers are collected by the vacuum trap, the spray liquid flow rate required by the scraper condenser will be greatly reduced, reducing energy consumption, and the stability of the vacuum system will be greatly improved; in addition, the discharge from the scraper condenser The residue of the hot well will be greatly reduced, the stability of the scraper operation will be improved, and the service life of the scraper will be greatly extended.

As a further improvement of the present invention, the top of the hot well is provided with a top cover of the hot well, a longitudinal partition is arranged along the longitudinal axis of the hot well to divide the inner cavity of the hot well into two halves, and the middle section of the longitudinal partition is symmetrically arranged on both sides There are a left inner chamber and a right inner chamber. The outer side of the lateral wall panel of the left inner chamber is the left outer chamber, and the outer side of the transverse wall panel of the right inner chamber is the right outer chamber. The bottoms of the left inner chamber and the right inner chamber are respectively provided with cones. The bottom of the two conical hoppers are respectively connected with hot well slag discharge ports, and the two hot well slag discharge ports respectively extend downward to outside the bottom of the hot well; the bottoms of the left outer chamber and the right outer chamber are respectively provided with The hot well liquid phase outlet; the hot well top cover is inserted with two atmospheric legs, the lower ends of the two atmospheric legs are respectively inserted into the lower part of the inner cavity of the left and right inner chambers, and the upper part of each horizontal wall panel They are respectively provided with overflow ports communicating with the corresponding outer chambers, and the inner ports of each overflow port are respectively covered with filter plates. The outer ports of the overflow ports are respectively covered with convex arc-shaped filter baskets, and the left and right sides of each arc-shaped filter basket are respectively inserted into the vertical slots on the outer end surface of the transverse wallboard. BDO and some oligomers flow into the lower part of the left inner chamber through the valve and pipe at the bottom of the scraper condenser through the left atmospheric leg, and at the same time play a role of liquid sealing. BDO or other spray liquid will pass through the filter plate for the first time. After filtering, it flows out and enters the inner cavity of the arc-shaped filter basket. After being filtered by the arc-shaped filter basket, it enters the left outer chamber, flows out from the liquid phase outlet of the hot well at the bottom of the left outer chamber, and is pumped out by the spray circulating pump and cooled After that, it is sent to the scraper condenser for circulating spraying. Impurities such as oligomers are blocked in the left inner chamber, fall into the cone-shaped hopper, and are discharged from the slag outlet of the hot well and enter the cleaning box. If the left atmospheric leg is blocked, you can immediately switch to the right atmospheric leg to work, and the liquid phase outlet of the hot well and the slag outlet of the hot well are also switched to the right, so that the sprinkler system can operate stably for a long time. , To ensure the normal operation of the polymerization device, avoid the shutdown due to the blockage of the atmospheric leg, greatly reduce the loss, and ensure the normal operation of the production. The filter plate is the first filter to trap larger-sized impurities. The filter plate of the present invention is close to the top of the hot well, which facilitates the extraction of the filter plate for cleaning, and is also easy to reassemble. The convex curved filter basket not only increases the filtering area, but also increases the content space; the filter plate and the edges of the left and right sides of the curved filter basket are embedded in the vertical slots, which is convenient for plugging and cleaning and assembly.

As a further improvement of the present invention, the hot well slag outlet is respectively connected with the cleaning box feed inlet on the top of the cleaning box, the cleaning box includes a horizontal cylinder with one end closed, and the front port of the cleaning box is hinged with Open and close the cover of the cleaning box, the cylinder body of the cleaning box is covered with a cleaning box jacket, and the inner cavity of the cleaning box is provided with a plurality of square filter drawers stacked in sequence from top to bottom, and each square filter The frames on the left and right sides of the drawer are respectively supported by rollers in the guide chute. Each guide chute extends along the axial direction of the cleaning box and is respectively fixed on both sides of the inner wall of the cleaning box. The bottom of the inner cavity of the cleaning box is provided with an arc The bottom of the arc-shaped bottom drawer is supported by rollers on the bottom of the inner wall of the cleaning box. The bottom of the arc-shaped bottom drawer and each square filter drawer are respectively provided with a filter screen, and the number of meshes of the lower filter screen is sequentially greater than The mesh size of the upper filter screen, the lower end of the feed opening of the cleaning box points to the center area of the top square filter drawer, and the bottom center of the cleaning box is provided with a cleaning box drain. The frame of each drawer is erected upwards to prevent the mixture from overflowing around the filter screen. The guiding chute is convenient for the square filter drawer to be removed for cleaning and put back, and it can ensure that the square filter drawers are in a horizontal state; the curved bottom drawer is located in the cleaning box The arc-shaped bottom of the cleaning box is in a stable and balanced state, and the guiding chute can be omitted, and it is directly supported on the arc-shaped bottom of the cleaning box by rollers. The mixture of oligomer and BDO enters the inner cavity of the cleaning box from the feed port of the cleaning box, and first falls on the square filter drawer on the top layer to coarsely filter the mixture. The top filter screen has large meshes and strong liquid permeability. It will not block and cause overflow, the largest slag will be intercepted, and the smaller slag will fall into the next layer to continue filtering; this way, the filtration accuracy is improved layer by layer, and the smallest slag will be intercepted by the arc-shaped bottom drawer. After filtering step by step, the clean BDO is discharged from the liquid outlet of the cleaning tank at the bottom of the cleaning tank. Open the cover of the cleaning box, and the square filter drawer or the arc-shaped bottom drawer can be drawn out for cleaning. Because the arc-shaped bottom drawer has the smallest holes and is the easiest to block, the frequency of cleaning can be higher than that of other square filter drawers. All are taken out for cleaning, reducing the workload of cleaning and reducing the pollution to the working environment on site; and the arc-shaped bottom drawer has the deepest depth and high content height, which is not easy to cause overflow. Steam can be introduced into the jacket of the cleaning box to increase the temperature of the cavity of the cleaning box to avoid blockage caused by solidification of the medium.

Description of the drawings

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. The accompanying drawings are only provided for reference and illustration, and are not intended to limit the present invention.

Fig. 1 is a flow chart of the production system of PBS-type biodegradable materials of the present invention.

Figure 2 is a flow chart of the slice drying system of the present invention.

Fig. 3 is a front view of the slice drying tower 1 or the slice drying tower 2 in Fig. 2.

Fig. 4 is a top view of Fig. 3.

Fig. 5 is a top view of one of the embodiments of the baffle in Fig. 3.

Fig. 6 is a cross-sectional view of the mixed silo in Fig. 3.

Figure 7 is a detailed flow diagram of the oligomer capture system of the present invention.

Figure 8 is a front view of the thermal well in the present invention.

Fig. 9 is a top view of Fig. 8 with the atmospheric legs removed.

Fig. 10 is a cross-sectional view along A-A in Fig. 9.

Fig. 11 is a partial enlarged view of Fig. 8.

Fig. 12 is a front view of the cleaning box in Fig. 7;

Fig. 13 is a left side view of Fig. 12.

In the picture: 1a. Slurry preparation tank one; 1a1. PTA feed port; 1b. Slurry preparation tank two; 1b1. Dibasic acid feed port; 2a. Slurry configuration tank one; 2b. Slurry configuration tank two; 3a .A esterification kettle; 3b.B esterification kettle; 4. second esterification kettle; 5. first polycondensation kettle; 6. second polycondensation kettle; 7. final polycondensation reactor; 8. viscosity increasing reactor; 9. .Chain extender addition system; 10a. Pelletizer one; 10b. Pelletizer two; 11. Slicing intermediate silo; 11a. Intermediate silo discharge valve; 12-1. Slicing drying tower one; 12-2. Slice drying tower two; 12a. Slice feed inlet; 12b. Tower body hot air outlet; 12c. Pressure measurement port; 12d. Tower body temperature measurement interface; 12e. Sight glass; 12f. Spare port; 12g. Reserved valve port; 12h. Manhole; 12j. Material level gauge interface; 12k. Distributing umbrella cap; 12m. Baffle plate; 12m1. Baffle plate hot blast hole; 12n. Drying tower cone; 12n1. Stirring shaft; 12n2. Stirring disc ; 12p. Discharge cone; 12p1. Slice discharge port; 12p2. Hand hole; 12q. Baffle air supply ring tube; 12r. Tower body air supply ring tube; 12r1. Baffle hot air interface; 12s. Discharge Cone air supply ring pipe; 13. Drying tower discharge valve; 14. Drying tower pants tee; 15. Slice batching hopper; 15a. Slice batching valve; 16. Mixing bin; 16a. Main feed inlet; 16b. Auxiliary Feeding port; 16c. Mixing chute; 16c1. Feeding port; 16d. Mixing silo pants tee; 17-1. Vacuum packaging machine one; 17-2. Vacuum packaging machine two; 18. Dust collector; 19 Gas heater; 20. Vacuum trap; 20a. Catcher level gauge; 20b. Electric shut-off valve; 21. Vacuum collection tank; 21a. Collection tank nitrogen valve; 21b. Collection tank discharge valve; 22. Scraper condensation 23. Hot well; 23a. Hot well slag outlet; 23b. Hot well liquid phase outlet; 23c. Hot well material level gauge mouth; 23d. Hot well thermometer mouth; 23e. Hot well roof; 23e1. Hot well Manhole cover; 23f. Longitudinal partition; 23g. Transverse wall panel; 23h1. Left inner chamber; 23h2. Right inner chamber; 23j1. Left outer chamber; 23j2. Right outer chamber; 23k. Seal seat; 23k1. Packing; 23k2 . Packing gland; 23m. Filter plate; 23m1. Filter plate handle; 23n. Curved filter basket; 23n1. Filter basket handle; 23p. Conical hopper; 23q. Atmospheric leg; 24. Cleaning box; 24a. Discharge port; 24b. Cleaning tank exhaust port; 24c. Cleaning tank drain port; 24d. Cleaning tank cover; 24e. Cleaning tank jacket; 24e1. Cleaning tank jacket lower interface; 24e2. Jacket upper interface; 24f .Square filter drawer; 24g. Curved bottom drawer; 24h. Roller; 24j. Guide chute; 24k. Searchlight port; 24m. Glass sight glass observation port; 24n. Multi-pipeline interface; 25. Process tower; 26. Tower Top reflux tank; 27. Cold trap; 28. Vacuum Pump; 29a. Jet pump one; 29b. Jet pump two; G0. BDO supply pipe; G1. Air delivery pipe one; G2. Air delivery pipe two; G3. Air delivery pipe three; G4. Dust removal suction pipe; G5 Return air pipe; G6. Nitrogen pipe; G7. Hot air main pipe; G8. Cold air branch pipe; G9. Steam pipe; G10. Condensate pipe; G11a. Heat medium oil supply pipe; G11b. Heat medium oil return pipe; V1. Heat supply regulation Valve; V2. Cold air regulating valve; T1. Hot air temperature sensor; T2. Baffle plate supply air temperature sensor; B1. Esterification material pump; B2. The first polycondensation material pump; B3. The second polycondensation material pump; B4. Melting Body transfer pump; B5. Melt booster pump one; B6. Melt metering pump; B7. Melt booster pump two; B8. Spray circulation pump; F1. Filter one; F2. Filter two; F3. Filter three; F4. Filter four; F5. Filter five; F6. Filter six; H1. Melt heat exchanger; H2. Circulating liquid cooler.

detailed description

In the following description of the present invention, the terms "front", "rear", "left", "right", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. , Is only for the convenience of describing the present invention and simplifying the description, and does not mean that the device must have a specific orientation.

As shown in Figure 1, the PBS biodegradable material production system of the present invention includes an esterification reaction vessel, a first polycondensation vessel 5, a second polycondensation vessel 6, a final polycondensation reaction vessel 7 and a viscosity-increasing reaction vessel 8. The reaction kettle includes an A esterification kettle 3a, a B esterification kettle 3b and a second esterification kettle 4. The top of the slurry mixing tank 1a is connected to the BDO supply pipe G0 and is provided with a PTA feeding port 1a1. The discharge port of the slurry mixing tank 1a is connected to the top inlet of the slurry configuration tank 2a, and the slurry configuration tank 1 The discharge port of 2a is connected to the slurry inlet on the top of A esterification tank 3a through a screw transfer pump. The top of the slurry mixing tank 2 1b is connected with the BDO supply pipe G0 and is provided with a dibasic acid feed port 1b1. The discharge port of the slurry mixing tank 2 1b is connected to the top inlet of the slurry configuration tank 2b, and the slurry is configured The discharge port of the second tank 2b is connected to the slurry inlet on the top of the B esterification tank 3b through a screw transfer pump. The gas phase ports of the A esterification tank 3a and the B esterification tank 3b are respectively connected to their respective process towers 25. The process towers 25 are respectively equipped with a top reflux tank 26. The gas ports of the top reflux tank 26 respectively pass through a cold trap 27 and a vacuum pump 28 connected.

The discharge ports of the A esterification tank 3a and the B esterification tank 3b are respectively connected to the feed port of the second esterification tank 4, and the discharge port of the second esterification tank 4 passes through the esterification material pump B1 and the filter 1 F1 It is connected to the feed port of the first polycondensation reactor 5, and the discharge port of the first polycondensation reactor 5 is connected to the feed port of the second polycondensation reactor 6 through the first polycondensation material pump and filter 2 F2. The discharge port is connected to the feed port of the final polycondensation reactor 7 through the second polycondensation material pump B3 and filter three F3, and the discharge port of the final polycondensation reactor 7 is connected to the viscosity increasing through the melt transfer pump B4 and the filter four F4. The feed port of the reactor 8 is connected.

BDO and PTA are blended in batches in slurry blending tank 1a according to a certain molar ratio, fully stirred and sent to slurry configuration tank 2a, and then from slurry configuration tank 2a to A esterification kettle via screw transfer pump The esterification reaction is carried out in 3a; BDO and adipic acid, sebacic acid, succinic acid or other dibasic acids are mixed in batches in slurry preparation tank 2 1b according to a certain molar ratio, and then sent to the slurry configuration tank after fully stirring. Two 2b, and then from the slurry configuration tank two 2b through the screw transfer pump into the B esterification tank 3b for esterification reaction. Since the reaction temperature of dibasic acid such as adipic acid and BDO is 170-210℃, the reaction temperature of PTA and BDO is 230～250℃. According to the temperature and pressure required for their reaction, the esterification reaction can be carried out separately. The consumption of BDO is greatly reduced, the production of tetrahydrofuran is reduced, and the quality of the material can be precisely controlled. The esterified esters of B and A are sent to the second esterification tank 4 for mixed esterification, the mixed esterification materials enter the first polycondensation tank 5 for pre-condensation, and the pre-condensation materials enter the second polycondensation. The kettle 6 undergoes recondensation, the recondensation material enters the final polycondensation reactor 7 for final polycondensation, and the final polycondensation material enters the viscosity increasing reactor 8 to increase the viscosity.

Pelletizing route 1: The discharge port of the thickening reactor 8 is connected to the pelletizer 10a through the melt booster pump one B5 and the filter five F5, and the melt after the thickening reactor 8 is thickened by the melt The booster pump B5 is sent to the pelletizer and the pelletizer is 10a, which can meet the needs of most customers, including the requirements of food-grade products.

Pelletizing route 2: The outlet of the melt transfer pump B4 is connected to the feed inlet of the melt heat exchanger H1 through the melt metering pump B6, the outlet of the melt heat exchanger H1 and the outlet of the chain extender addition system 9 Together with the inlet of the second melt booster pump B7, the discharge port of the second melt booster pump B7 is connected to the second pelletizer 10b through the filter six F6. After the final polycondensation material is sent by the melt transfer pump B4, it is first measured by the melt metering pump B6, and then the temperature is adjusted by the melt heat exchanger H1, and then enters the melt increase together with the modified material from the chain extender addition system 9 Pressure pump two B7, the melt booster pump two B7 is sent to the pelletizer two 10b to cut pellets, which can realize the online modification of some products. The melt line is short, the residence time is short, it is not easy to thermally decompose, and the product quality is good; At the same time, the compatibility of the system is good, and products with different characteristics can be produced to satisfy different downstream customers.

The gas phase ports of the first polycondensation tank 5, the second polycondensation tank 6, the final polycondensation reaction tank 7 and the viscosity-increasing reaction tank 8 are respectively connected to their respective oligomer capture systems, and each oligomer capture system includes a scraper condenser, The gas phase port of the scraper condenser of the first polycondensation reactor 5 is connected to a vacuum pump 28 through a cold trap 27. The gas port of the scraper condenser of the second polycondensation tank 6 and the gas port of the scraper condenser of the final polycondensation reactor 7 are connected to jet pump one 29a, and the gas port of the scraper condenser of the thickening reactor 8 is connected to jet pump 2. 29b, the exhaust ports of jet pump one 29a and jet pump two 29b are connected to the corresponding vacuum pump 28 through their respective cold traps 27.

As shown in Fig. 1 and Fig. 2, the outlets of pelletizer one 10a and pelletizer two 10b are respectively connected to the respective middle slicing silo 11, and the bottom of the slicing middle silo 11 is provided with an intermediate silo discharge valve 11a, The outlet of the discharging valve 11a of the intermediate silo is connected to the slice feed port 12a at the top of the slice drying tower 12-1 through the air conveying pipe G1, and the slice discharge port 12p1 at the bottom of the slice drying tower 12-1 is connected to the drying tower outlet. The inlet of the feed valve 13 is connected, and the outlet of the drying tower discharge valve 13 is connected to the slice feed port 12a on the top of the slice drying tower two 12-2 through the second air pipe G2, and the slice at the bottom of the slice drying tower two 12-2 is discharged The port 12p1 is connected to the main feed port 16a of the mixing silo 16, and the outlet of the mixing silo 16 is connected to the vacuum packaging machine.

The PBS-type slices in the slice intermediate silo 11 are discharged through the intermediate silo discharge valve 11a, and enter the slice drying tower 12-1 under the conveyance of the air conveying pipe G1, and the slices and hot air are in the slice drying tower 12-1. The heat and moisture exchange is carried out, the water and tetrahydrofuran are evaporated, and the preliminarily dried slices are discharged from the discharge valve 13 of the drying tower, and enter the slice drying tower two 12-2 under the conveying of the air duct two G2, and in the slice drying tower two 12-2 The middle slice and the hot air continue to exchange heat and moisture. After the remaining moisture and tetrahydrofuran are evaporated, they enter the mixing bin 16 from the main feed port 16a for temporary storage, and then enter the vacuum packaging machine for packaging. Due to the two-stage series evaporation, the water and tetrahydrofuran in the PBS-type slices are removed, and the vacuum packaging is adopted, and the product will not be degraded after being placed for a period of time. The quality of the product has increased by one level, which can meet the requirements of food-grade use.

The hot air outlet 12b at the top of the chip drying tower 12-1 and the chip drying tower 2 12-2 is connected to the air inlet of the dust collector 18 through the dust suction duct G4, and the air outlet at the top of the dust collector 18 passes through the return air duct G5 Connected to the air supply port of the air supply pipe three G3, the feed port of the air supply pipe three G3 is connected to the outlet of the slice batching valve 15a, the inlet of the slice batching valve 15a is connected to the outlet of the slice batching hopper 15, and the air supply pipe of three G3 The outlet is connected to the auxiliary feed inlet 16b of the mixed silo 16. The hot air after moisture absorption is discharged from the hot air outlet 12b at the top of the slice drying tower 12-1 and the slice drying tower 2 12-2, and enters the dust collector 18 through the dust suction duct G4, and the dust in the slice is intercepted by the dust collector 18. , The clean exhaust gas enters the air supply duct G3 through the return air duct G5 for recycling. The slices of different molecular weights have different viscosities. The ingredients are temporarily stored in the slice batching hopper 15, discharged from the slice batching valve 15a, and enter the mixing silo 16 from the auxiliary feed port 16b under the transportation of the air conveying pipe G3, and from the main feed port 16a enters the freshly dried slices and mixes evenly according to the proportion. Change the mixing ratio. The mixed slices can be extruded to obtain melts with different viscosities. The product has a wider application range. At the same time, the waste heat and nitrogen in the clean exhaust gas are recovered, which greatly reduces This reduces the consumption of heat and material.

As shown in Figure 6, the main feed port 16a is located at the top center of the mixing silo 16, the auxiliary feed ports 16b are located symmetrically on both sides of the main feed port 16a, and the inner cavity of the mixing silo 16 is provided with at least three mixing chutes. Tube 16c, each mixing chute 16c extends vertically and is symmetrically distributed around the axis of the mixing silo. The height direction of 16c is uniformly provided with a plurality of slidable cross sections, each slidable cross section is respectively provided with a slidable opening 16c1, and each slidable opening 16c1 is spirally distributed along the circumference of the mixing chute 16c.

The main feed port 16a and the auxiliary feed port 16b feed at the same time and fall above the material layer at the same time to achieve static mixing in each section of the mixing silo 16. The bottom outlet flows out and realizes first-in-first-out; part of the slices in the peripheral area of the mixing silo enter the inner cavity of the mixing chute 16c from each chute 16c1, and quickly descend along the mixing chute 16c and fall into the cone of the mixing silo 16 In the hopper, the last-in-first-out of partial slices is realized, and the dynamic mixing is realized in the height direction of the mixing silo 16. The first-in first-out static mixing and the last-in first-out dynamic mixing work together. The slice drying tower and the slice batching hopper 15 The arranged slices are uniformly mixed in the mixing bin 16, which greatly improves the uniformity and quality of the mixed slices. The mixing chute 16c is symmetrically distributed in the center, and the chute 16c1 on the mixing chute 16c is evenly distributed in the height direction and the circumferential direction, which can further improve the uniformity of the slice mixing.

The slice discharge port 12p1 at the bottom of the slice drying tower two 12-2 is equipped with a drying tower pant tee 14. The two outlets of the drying tower pant tee 14 are respectively connected to the main feed inlet 16a of the two mixing silos 16, and the air supply pipe The outlets of the three G3 are respectively connected with the auxiliary feed inlets 16b of the two mixing silos 16; the bottom outlets of the two mixing silos 16 are respectively installed with the mixing silo pant tee 16d, and the outlets of the mixing silo pant tee 16d are respectively connected to the vacuum The feeding ports of the packaging machine one 17-1 and the vacuum packaging machine two 17-2 are connected. The slicing drying tower two 12-2 can choose the mixing bin 16 arbitrarily through the drying tower pants tee 14. The two mixing bins 16 can adopt different mixing ratios, and the bottoms of the two mixing bins 16 respectively pass the mixing bin tee 16d It can be connected with vacuum packaging machine one 17-1 or vacuum packaging machine two 17-2, vacuum packaging machine one 17-1 can be a ton packaging machine, vacuum packaging machine two 17-2 can be a 25kg packaging machine, to meet different customers The viscosity requirements and the large and small packaging requirements.

The slice drying tower 1 12-1 and the slice drying tower 2 12-2 each include a vertical cylindrical tower body. The top center of the tower body is provided with a slice inlet 12a, and the hot air outlet 12b of the tower body is located at the slice inlet 12a. One side; the lower part of the tower body is provided with a tower body hot air inlet, the bottom of the tower body is connected with a drying tower cone 12n, and the slice discharge port 12p1 is located at the lower end of the drying tower cone 12n. There are multiple channels along the axis of the tower body. The cone-shaped material distributing umbrella cap 12k, except for the top material distributing umbrella cap 12k, the upper part of each material distributing umbrella cap 12k and the bottom of the bottom material distributing umbrella cap 12k are respectively provided with a baffle 12m coaxial with it. The 12m of the flow plate is in the shape of a bell mouth with a large top and a small bottom.

As shown in Figure 3, PBS slices enter the inner cavity of the tower from the slice feeding port 12a at the top, and first fall on the outer cone of the top layer of the distributing umbrella cap 12k. After splashing, they evenly spread around, and then fall downwards. On the inner cone surface of the baffle 12m, it splashes toward the center and falls from the center hole of the baffle 12m and falls on the outer cone surface of the distributing umbrella cap 12k of the next layer; hot nitrogen or hot air from the tower The lower part of the body enters and heats it during the upward flow against the PBS-like slices. In this way, in the process of turning back and flying downward for many times of PBS type slices, the water or THF is gradually removed, and finally the slices fall into the drying tower cone 12n and are discharged from the slice discharge port 12p1 at the bottom, and the hot air is discharged from the tower body at the top of the tower. The hot air outlet 12b is discharged.

The upper end of each baffle 12m is respectively connected to the inner wall of the tower body, each baffle 12m is a thin-walled cavity structure, and the lower wall of each baffle 12m is connected to the corresponding baffle through a plurality of evenly distributed radial connecting pipes. The baffle air supply loops 12q are connected. Each baffle air supply loop 12q surrounds the outer circumference of the tower and is respectively provided with baffle hot air interfaces 12r1. The upper wall of each baffle 12m is evenly distributed with multiple baffles. 12m1 hot air holes on the board. Hot nitrogen or hot air enters the inner cavity of each baffle 12m from the baffle supply ring pipe 12q along each radial connecting pipe, and sprays upwards from each baffle hot air hole 12m1 on the upper wall of the baffle 12m, and slices While falling on the baffle 12m, it is dried and agitated by the hot air sprayed from the baffle hot air hole 12m1, which further improves the drying effect and uniformity.

As shown in Figure 2, the nitrogen pipe G6 is connected to the air inlet of the gas heater 19, and the air outlet of the gas heater 19 is connected to the hot air main pipe G7. The hot air main pipe G7 is connected to the hot air branch pipes of each layer. The cold air branch pipes G8 of the same layer are connected to the baffle air supply pipe of this layer, and the outlets of the baffle air supply pipes of each layer are respectively connected to the baffle hot air interface 12r1 of the layer; the hot air temperature is installed on the hot air main pipe G7 Sensor T1, the hot side inlet of the gas heater 19 is connected to the steam pipe G9 through the heating regulating valve V1, the hot side outlet of the gas heater 19 is connected to the condensate pipe G10, and the opening of the heating regulating valve V1 is controlled by the hot air temperature The temperature measured by the sensor T1; the baffle air supply pipes of each layer are equipped with baffle air supply temperature sensors T2, and the cold air branch pipes G8 of each layer are respectively installed with a cold air regulating valve V2 and each cold air regulating valve V2 The opening degrees are controlled by the temperature measured by the temperature sensor T2 of the same layer of baffle.

After the nitrogen is heated by the gas heater 19, it enters the hot air main G7, and the temperature is measured by the hot air temperature sensor T1. If the temperature of the hot air is low, increase the opening of the heating regulating valve V1; if the temperature of the hot air is high, then Reduce the opening of the heating regulating valve V1. Then the hot air enters the hot air branch pipes of each layer, mixes with the cold air from the cold air branch pipe G8 of the same layer, enters the baffle air supply pipe of this layer, and then enters the baffle 12m of the layer through the baffle air supply loop 12q . When the temperature detected by the air supply temperature sensor T2 of a certain layer of baffle is low, the cold air regulating valve V2 of this layer is closed; otherwise, the cold air regulating valve V2 of this layer is opened. In this way, through the multi-layer and independent temperature control system, according to the control process requirements of the drying tower, different temperatures are controlled in stages to achieve high-efficiency removal of water and tetrahydrofuran.

As shown in Figure 3, the diameter of the upper end of the drying tower cone 12n is larger than the diameter of the tower body, and the lower end of the tower body is inserted into the upper port of the drying tower cone 12n, and the upper port of the drying tower cone 12n is provided with an annular seal The inner edge of the ring cover is welded to the outer wall of the tower body; the ring cavity under the ring cover is connected to the tower body air supply ring 12r through a plurality of evenly distributed radial communication pipes, and the tower body air supply ring A tower body hot air inlet is provided on the circumference of the tube 12r, and an annular hot air channel with a downward opening is provided between the lower port of the tower body and the inner wall of the drying tower cone 12n. There are four or six radial connecting pipes evenly distributed on the same circumference to ensure that the hot air is evenly distributed on the circumference of the tower body and to ensure that the slices on the same section are evenly heated. The hot air enters the annular cavity at the upper end of the drying tower cone 12n from the tower body air supply ring pipe 12r along each radial connecting pipe, and blows downward from the annular hot air passage between the tower body and the drying tower cone 12n, and The drying tower cone 12n is in a flow state first along the circumferential wall and then upwards along the central area. The slices falling into the drying tower cone 12n are heated and loosened to prevent sticking to the wall and mutual adhesion causing blockage, etc. .

The lower part of the drying tower cone 12n is provided with a stirring rotor. The stirring rotor includes a stirring shaft 12n1 and a plurality of stirring discs 12n2 fixed on the stirring shaft 12n1. Both ends of the stirring shaft 12n1 are respectively supported on the drying tower cone 12n through a bearing seat. The upper part is sealed with the cone wall of the drying tower, and the diameter of the stirring disc 12n2 gradually decreases from the middle section of the stirring shaft 12n1 to both ends. The stirring shaft drives each stirring disc 12n2 to rotate, and stirs the slices falling into the drying tower cone 12n to keep them in a loose state to prevent blockage caused by adhesion. The diameters of the stirring discs 12n2 are distributed in steps, which can better match the shape of the drying tower cone 12n, and agitate the slices more thoroughly.

The lower end of the drying tower cone 12n is nested with a discharge cone 12p, the upper port of the discharge cone 12p is closed and nested on the outer circumference of the lower end of the drying tower cone 12n, and the annular cavity at the lower end of the drying tower cone 12n passes through multiple The uniformly distributed radial connecting pipe is connected with the discharge cone air supply ring tube 12s. The discharge cone hot air interface is provided on the circumference of the discharge cone air supply ring tube 12s. The lower port of the drying tower cone 12n and the discharge cone 12p An annular hot air channel with downward opening is provided between the inner walls of the slab, and the slicing discharge port 12p1 is located at the lower end of the discharge cone 12p. The hot air flows from the discharge cone air supply ring pipe 12s along the radial connecting pipes into the annular cavity at the connection part of the drying tower cone 12n and the discharge cone 12p, and downwards from the drying tower cone 12n and the discharge cone 12p. The annular hot air channel blows downwards in the discharge cone 12p first along the circumferential wall, and then blows out from the stirring rotor upward along the central area. On the one hand, the slices falling into the discharge cone 12p are further heated, and the other On the one hand, the slices are rolled and loosened to prevent sticking to the wall and blockage caused by mutual adhesion.

The circumferential wall of the discharge cone 12p is provided with a hand hole 12p2 communicating with the inner cavity, and the upper and middle circumferences of the tower body are respectively provided with manholes. If the slicing outlet 12p1 is still blocked, you can open the hand hole 12p2, and you can easily remove the material from the hand hole 12p2, so that the equipment can be restored unblocked, avoiding the removal of the pipe or entering from the upper manhole for segmented cleaning Or overhaul to reduce the parking processing time.

As shown in Figure 4, the top seal head of the tower body is also provided with a pressure measuring port 12c, a tower body temperature measuring port 12d, a sight glass 12e, a spare port 12f and a reserved valve port 12g, the upper and middle circumferences of the tower body There are 12h manholes on each. The pressure measurement of the inner cavity of the tower can be performed through the pressure measuring port 12c, and the flow state of the slices in the tower can be observed through the sight glass 12e, and the tower can be entered from the manhole 12h to clean or repair the inner cavity of the tower in sections.

The tower body is provided with multiple tower body temperature measurement interfaces along the height direction, and each tower body temperature measurement interface is equipped with a drying tower temperature transmitter; the tower body is provided with multiple level meter interfaces 12j along the height direction, and each material level A material level alarm is installed in the meter interface 12j respectively. The temperature transmitter of the drying tower can measure the temperature of different cylinder sections in the tower in real time, so as to control the air supply temperature of 12m into different baffles. The material level alarm is set up in stages. When an abnormality occurs, different solutions can be adopted according to the material level condition.

As shown in Figure 5, each baffle 12m can be formed by splicing a plurality of fan-shaped plates distributed in an annular array. The angle between the flow plate 12m and the axis of the tower body is smaller. The angle between each layer of baffle 12m and the vertical wall of the tower can be adjusted to control the descent speed of the slices. By adjusting the angle of the baffle 12m, the residence time of the slices in each section of the tower can be controlled to suit Slices with different properties and particle sizes ensure more efficient removal of water and tetrahydrofuran from the slices. Since the slices that have just entered the drying tower have a relatively high water content, the baffle 12m is set relatively flat to extend the contact time with the hot air and increase the evaporation; the slices that have reached the lower part of the tower have been basically dried, and the evaporation is small. The 12m baffle is set relatively steeply to increase the descending speed of the slices. The upper part of the tower body shows a slow descending speed of the slices, and the lower part of the slices descends fast, which greatly reduces the possibility of blockage in the tower. The 12m splicing seams of two adjacent layers of baffles are staggered, and a small amount of slices falling from the splicing seams will all fall on the next layer of baffles 12m, avoiding long-height blanking short circuits in the slices.

As shown in Figure 7, the gas phase outlet of each polycondensation reactor or thickening reactor is connected to the side wall inlet of the vacuum trap 20 through a jacketed pipe, and the top gas outlet of the vacuum trap 20 is connected to the scraper condenser 22 through the jacket pipe The air inlet is connected. The bottom outlet of the vacuum trap 20 is connected to the top inlet of the vacuum collection tank 21 through the electric shut-off valve 20b. The top air inlet of the vacuum collection tank 21 is also connected to the nitrogen pipe G6 through the collection tank nitrogen valve 21a. The bottom of the collection tank 21 is provided with a collection tank discharge valve 21b; the medium outlet of the scraper condenser 22 is connected to the hot well 23 through the atmospheric leg 23q, and the hot well liquid phase outlet 23b is connected to the inlet of the spray circulation pump B8, and the spray circulation The outlet of the pump B8 is connected with the inlet of the circulating liquid cooler H2, and the outlet of the circulating liquid cooler H2 is connected with the spray port of the scraper condenser 22.

After the mixture of BDO, water and oligomer is discharged from the gas-phase port of each polycondensation vessel or viscosity increasing vessel, it first enters the vacuum trap 20. Due to the decrease of the gas velocity, the liquid oligomer is trapped in the vacuum under the action of gravity. At the bottom of the condenser 20, BDO, water and a small amount of oligomers enter the scraper condenser 22 to be sprayed and collected. The condensed oligomers are discharged from the medium outlet of the scraper condenser 22 with the BDO and enter the heat through the atmospheric leg 23q. It is filtered in the well, and the spray liquid BDO is pumped out by the spray circulating pump B8, cooled by the circulating liquid cooler H2, and returned to the spray port of the scraper condenser 22 for circulating spray.

When a certain level gauge is accumulated in the vacuum trap 20, open the electric shut-off valve 20b, the nitrogen in the vacuum trap 21 enters the vacuum trap 20 and is discharged from the gas phase port, and the liquid oligomer enters the vacuum trap 21 After storing to a certain amount, open the collection tank nitrogen valve 21a of the vacuum collection tank 21, fill the vacuum collection tank 21 with nitrogen, and open the collection tank discharge valve 21b at the bottom of the vacuum collection tank 21 to remove the liquid oligomer The waste is discharged into the collection tank, and after the discharge is completed, nitrogen is continuously supplied for about 10 seconds, the vacuum collection tank 21 is nitrogen-sealed, and then the collection tank nitrogen valve 21a is closed.

Since most of the oligomers are collected by the vacuum trap 20, the spray liquid flow consumed by the scraper condenser 22 will be greatly reduced, reducing energy consumption, and the stability of the vacuum system will be greatly improved; in addition, from the scraper condenser 22 The amount of residue discharged into the hot well will be greatly reduced, the stability of the scraper operation will be improved, and the service life of the scraper will be greatly extended.

The outer walls of the vacuum trap 20 and the vacuum collection tank 21 are respectively coiled with half-pipe heaters. The lower inlets of the two half-pipe heaters are respectively connected with the heating medium oil supply pipe G11a, and the upper outlets of the two half-pipe heaters are respectively connected with the heating medium return. The oil pipe G11b is connected. Through the heating of the heat medium, the vacuum trap 20 and the vacuum collecting tank 21 can be kept above the melting point of various media, ensuring that the various media maintain fluidity, and avoiding solidification and clogging.

A trap level gauge 20a is installed on the middle section of the side wall of the vacuum trap 20, the opening and closing of the electric shut-off valve 20b is controlled by the trap level gauge 20a, and the vacuum collection tank 21 is equipped with a pressure sensor. When the liquid level in the vacuum trap 20 reaches the height of the trap level gauge 20a, the electric shut-off valve 20b opens to discharge the liquid. The pressure of the vacuum collecting tank 21 can be observed through the pressure sensor, and the completion of the nitrogen seal and the formation of negative pressure can be judged.

As shown in Figures 8 to 10, the top of the hot well 23 is provided with a hot well top cover 23e, and a longitudinal partition 23f is provided along the longitudinal axis of the hot well 23 to divide the inner cavity of the hot well into left and right halves. The longitudinal partition 23f In the middle section, there are symmetrical left inner chamber 23h1 and right inner chamber 23h2. Left inner chamber 23h1 and right inner chamber 23h2 are provided with transverse wall panels 23g before and after respectively. The outer space of left inner chamber 23h1 is left outer chamber 23j1 and right inner chamber 23h1. The outer space of the chamber 23h2 is the right outer chamber 23j2. The bottoms of the left inner chamber 23h1 and the right inner chamber 23h2 are respectively provided with a conical hopper 23p. The well slag outlets 23a respectively extend downwards to the bottom of the hot well 23; the bottoms of the left outer chamber 23j1 and the right outer chamber 23j2 are respectively provided with the hot well liquid phase outlet 23b; the top cover 23e of the hot well is plugged with two atmospheres The lower ends of the legs 23q and the two atmospheric legs 23q are respectively inserted into the lower part of the inner cavity of the left inner chamber 23h1 and the right inner chamber 23h2. The inner ports are respectively covered with filter plates 23m, the left and right sides of each filter plate 23m are respectively inserted into the vertical slots on the inner end surface of the transverse wall panel 23g, and the outer ports of each overflow port are respectively covered with convex arc-shaped filters. For the basket 23n, the left and right sides of each arc-shaped filter basket 23n are respectively inserted into the vertical slots on the outer end surface of the horizontal wallboard 23g.

BDO and some oligomers flow into the lower part of the left inner chamber 23h1 through the valve and pipe at the bottom of the scraper condenser through the left atmospheric leg 23q, and at the same time play a role of liquid sealing. BDO is filtered upward through the filter plate 23m for the first time. It flows out into the inner cavity of the arc-shaped filter basket 23n, after being filtered by the arc-shaped filter basket 23n, enters the left outer chamber 23j1, flows out from the hot well liquid phase outlet 23b at the bottom of the left outer chamber 23j1, and is sprayed by the circulating pump B8 After being extracted and cooled, it is sent to the scraper condenser for circulating spraying. Impurities such as oligomers are blocked in the left inner chamber 23h1, fall into the cone-shaped hopper 23p, are discharged from the hot well slag outlet 23a and enter the cleaning box 24. If the left atmospheric leg 23q is blocked, you can immediately switch to the right atmospheric leg 23q to work, and the hot well liquid phase outlet 23b and the hot well slag outlet 23a also switch to the right to work, so that the sprinkler system can be long-term , Stable operation, to ensure the normal operation of the polymerization device, to avoid shutdown due to blockage of the atmospheric leg 23q, to greatly reduce losses, and to ensure the normal operation of production.

The filter plate 23m is the first filter to trap larger-sized impurities. The filter plate 23m of the present invention is close to the top of the vacuum sealed tank, which facilitates the extraction of the filter plate 23m for cleaning and easy assembly. The convex curved filter basket 23n not only increases the filtering area, but also increases the content space; the edges on the left and right sides of the filter plate 23m and the curved filter basket 23n are embedded in the vertical slots for easy insertion and cleaning And assembly.

Each arc-shaped filter basket 23n extends to the lower part of the corresponding outer chamber, and the arc surface and bottom of each arc-shaped filter basket 23n are respectively provided with a filter screen. The filtering area of the arc-shaped filter basket 23n is further increased, so that the arc-shaped filter basket 23n only needs to be cleaned once after the system has been working continuously for several days, which reduces the cleaning workload.

As shown in Figure 11, two atmospheric legs 23q are respectively located on both sides of the longitudinal partition 23f, and respectively pass through the central hole of the sealing seat 23k. The two sealing seats 23k are respectively welded to the hot well top cover 23e, and the atmospheric legs 23q The stuffing box between the outer wall and the inner wall of the sealing seat is respectively provided with packing 23k1, the upper part of the packing 23k1 is respectively provided with a packing gland 23k2, and the flange of the packing gland 23k2 is connected with the flange of the sealing seat 23k by gland screws. Tighten the gland screws and press the packing 23k1 into the stuffing box through the packing gland 23k2, which is not only sealed on the outer circumference of the atmospheric leg 23q, but also can ensure vertical free sliding of the atmospheric leg 23q, which can automatically adapt to the expansion and contraction caused by the temperature change of the system .

Two hot well manhole covers 23e1 are symmetrically provided on the horizontal axis of the hot well top cover 23e away from the longitudinal partition 23f, and each pair of filter plates 23m and arc-shaped filter basket 23n are respectively located below the opening of the hot well manhole cover 23e1. Open the hot well manhole cover 23e1, the filter plate 23m and the curved filter basket 23n can be taken out for cleaning, the filter plate 23m and the curved filter basket 23n are cleaned and inserted back, and then the hot well manhole cover 23e1 is reset to avoid overall disassembly The hot well roof 23e reduces the workload during cleaning.

Each filter plate 23m and the top of the arc-shaped filter basket 23n are respectively provided with handles. The filter plate 23m can be easily inserted through the filter plate handle 23m1, and the arc-shaped filter basket 23n can be easily inserted through the filter basket handle 23n1.

The left inner chamber 23h1, the right inner chamber 23h2, the left outer chamber 23j1 and the right outer chamber 23j2 are respectively equipped with hot well material level gauge ports 23c, which can display and monitor the material level of the inner and outer chambers in real time on the DCS. When 23q is blocked, DCS will send out an alarm in real time, so that DCS personnel can quickly arrange for on-site personnel to deal with it.

The bottoms of both sides of the hot well 23 are respectively provided with hot well thermometer ports 23d, which can display the temperature of the BDO on the DCS in real time.

As shown in Figures 12 and 13, the cleaning box 24 includes a horizontal cylinder with one end closed. The front port of the cleaning box 24 is hinged with a cleaning box cover 24d that can be opened and closed. The box jacket 24e. The inner cavity of the cleaning box 24 is provided with a plurality of square filter drawers 24f stacked one after another from top to bottom. Each guide chute 24j extends along the axial direction of the cleaning box 24 and is respectively fixed on both sides of the inner wall of the cleaning box 24. The bottom of the inner cavity of the cleaning box 24 is provided with an arc-shaped bottom drawer 24g, and the bottom of the arc-shaped bottom drawer 24g passes through rollers. 24h is supported on the bottom of the inner wall of the cleaning box 24, the arc-shaped bottom drawer 24g and the bottom of each square filter drawer 24f are respectively provided with a filter, and the mesh number of the lower filter is sequentially greater than the mesh number of the upper filter, and the top of the cleaning box 24 The cleaning box inlet 24a and the cleaning box exhaust opening 24b are provided. The upper end of the cleaning box inlet 24a is connected with the hot well slag outlet 23a, and the lower end of the cleaning box inlet 24a points to the central area of the top square filter drawer 24f , The bottom center of the cleaning box 24 is provided with a cleaning box drain port 24c.

The borders of the drawers are erected upward to prevent the mixture from overflowing around the filter screen. The guiding chute 24j facilitates the removal of the square filter drawer 24f for cleaning and putting it back, and can ensure that the square filter drawer 24f is in a horizontal state; the curved bottom drawer 24g is located at the arc-shaped bottom of the cleaning box 24 and is in a stable and balanced state. The guide chute 24j can be omitted and directly supported on the arc-shaped bottom of the cleaning box 24 by rollers 24h. The mixture of oligomer and BDO enters the inner cavity of the cleaning box 24 from the inlet 24a of the cleaning box, and first falls on the square filter drawer 24f on the top layer to coarsely filter the mixture. The top filter screen has a large mesh and has a liquid permeability. It is very strong, will not block and cause overflow, the largest slag is intercepted, and all the smaller slag falls into the next layer to continue filtering; this way, the filtration accuracy is improved layer by layer, and the smallest slag is held by the curved bottom drawer 24g After being intercepted and filtered step by step, the clean BDO is discharged from the cleaning tank drain port 24c at the bottom of the cleaning tank 24. Open the cleaning box cover 24d, and then the square filter drawer 24f or the curved bottom drawer 24g can be taken out for cleaning. Because the curved bottom drawer 24g has the smallest holes and is the easiest to block, the frequency of cleaning can be higher than that of other square filter drawers 24f. There is no need to take out each layer for cleaning, reducing the workload of cleaning and reducing the pollution to the working environment on site; and the arc-shaped bottom drawer has the deepest 24g depth, high content height, and it is not easy to cause overflow.

The left and right sides of the exhaust port 24b of the cleaning box are respectively provided with a searchlight port 24k and a glass sight glass observation port 24m. The light is injected from the searchlight port 24k, and the internal interception state can be observed from the glass sight glass observation port 24m on the other side. In order to accurately determine the time of cleaning.

The bottom of the cleaning box jacket 24e is connected with a cleaning box jacket lower interface 24e1, and the top of the cleaning box jacket 24e is connected with a jacket upper interface 24e2, which can pass steam into the cleaning box jacket 24e, and the steam is from the top jacket The upper port 24e2 enters, and the condensed water is discharged from the lower port 24e1 of the cleaning tank jacket at the bottom, so as to increase the temperature of the inner cavity of the cleaning tank 24 and avoid the blockage caused by the solidification of the medium.

The top of the cleaning box 24 is also provided with a multi-pipeline interface 24n, which can be used for pressure measurement, liquid supplement or inert gas protection, etc.

The foregoing descriptions are only preferred and feasible embodiments of the present invention, and therefore do not limit the scope of patent protection of the present invention. In addition to the above-mentioned embodiments, the present invention can also have other embodiments. For example, the gas heater can be heated by a heat medium. All technical solutions formed by equivalent replacements or equivalent transformations fall within the protection scope of the present invention. The undescribed technical features of the present invention can be realized by or by using the existing technology, and will not be repeated here.

Claims

A PBS-type biodegradable material production system, comprising an esterification reactor, characterized in that: the esterification reactor includes an esterification pot A, an esterification pot B, and a second esterification pot, and the top of the esterification pot A The slurry inlet is connected with the discharge port of slurry configuration tank one, the top inlet of slurry configuration tank one is connected with the discharge port of slurry mixing tank one, and the top of slurry mixing tank one is connected with the BDO supply pipe and Equipped with a PTA feeding port; the slurry inlet on the top of the B esterification kettle is connected with the outlet of the slurry configuration tank two, and the top inlet of the slurry configuration tank two is connected with the discharge port of the slurry preparation tank two, and the slurry is prepared The top of tank two is connected with the BDO feed pipe and is provided with a dibasic acid feed port; the outlets of the A esterification kettle and the B esterification kettle are respectively connected to the inlet of the second esterification kettle, and the second esterification kettle The outlet of the chemical kettle is connected to the inlet of the first polycondensation kettle through the esterification material pump, and the outlet of the first polycondensation kettle is connected to the inlet of the second polycondensation kettle through the first polycondensation material pump. The outlet of the kettle is connected to the inlet of the final polycondensation reactor through the second polycondensation material pump, and the outlet of the final polycondensation reactor is connected to the inlet of the thickening reactor through a melt transfer pump.
The PBS-type biodegradable material production system according to claim 1, characterized in that: the discharge port of the thickening reactor is connected to the pelletizer through a melt booster pump one; the melt conveying The outlet of the pump is connected to the feed inlet of the melt heat exchanger via the melt metering pump, and the outlet of the melt heat exchanger and the outlet of the chain extender adding system are connected to the inlet of the melt booster pump 2 together. The discharge port of the second body booster pump is connected with the second pelletizer.
The PBS-type biodegradable material production system according to claim 2, wherein the outlets of the first pelletizer and the second pelletizer are respectively connected to their respective middle slicing bins, and the middle slicing bins The bottom of each silo is provided with a discharging valve for the middle silo, and the outlet of the discharging valve of each middle silo is connected to the slice feed port on the top of the slice drying tower through the air duct, and the slice discharge at the bottom of each slice drying tower The outlets are respectively connected with the inlet of the discharge valve of the drying tower, and the outlet of the discharge valve of each drying tower is connected to the slice feed port on the top of the slice drying tower two through the second air supply pipe, and the slice discharge port at the bottom of the slice drying tower two They are respectively connected with the main feed inlet of the mixed silo, and the outlet of each mixed silo is respectively connected with the vacuum packaging machine.
The PBS-type biodegradable material production system according to claim 3, wherein the hot air outlets on the top of the slice drying tower 1 and the slice drying tower 2 both pass through the dust suction duct and the air inlet of the dust collector Connected, the top air outlet of the dust collector is connected with the air supply port of the air supply pipe 3 through the return air pipe, and the feed port of the air supply pipe 3 is connected with the outlet of the slice batching valve, and the inlet of the slice batching valve is connected with the slice batching The outlet of the hopper is connected, and the outlet of the air conveying pipe 3 is connected with the auxiliary feed inlet of the mixing silo.
The PBS-type biodegradable material production system according to claim 4, wherein the main feed port is located at the top center of the mixed silo, and the auxiliary feed port is symmetrically located at the main feed On both sides of the opening, the inner cavity of the mixing silo is provided with at least three mixing chute, each mixing chute extends vertically and is symmetrically distributed with the axis of the mixing silo as the center, and the lower end of each mixing chute faces The cone at the bottom of the mixing silo is curved, and a plurality of sliding sections are uniformly arranged along the height direction of each mixing chute. Each chute section is provided with a chute, and each chute is along the line of the mixing chute. The circumference is spirally distributed.
The PBS-type biodegradable material production system according to claim 3, characterized in that: the slice drying tower one and the slice drying tower two respectively comprise a vertical cylindrical tower body, and the top center of the tower body is provided There is the chip inlet, the tower body hot air outlet is located on one side of the chip inlet; the lower part of the tower body is provided with the tower body hot air inlet, and the bottom of the tower body is connected with a drying tower Cone hopper, the slice discharge port is located at the lower end of the drying tower cone, along the axis of the tower body is provided with a plurality of right-cone-shaped distributing umbrella caps, except for the top distributing umbrella cap, each distributing umbrella cap The upper part of the umbrella cap and the lower part of the bottom material distributing umbrella cap are respectively provided with baffle plates coaxial with the baffle plates, and each baffle plate is in the shape of a bell mouth with a large upper part and a smaller lower part.
The PBS-type biodegradable material production system according to claim 6, wherein the upper end of each baffle plate is connected to the inner wall of the tower body, and each baffle plate has a thin-walled cavity structure, The lower wall of each baffle is respectively connected to the corresponding baffle air supply ring pipe through a plurality of evenly distributed radial communication pipes, and each baffle air supply ring pipe surrounds the outer periphery of the tower body and is respectively provided with The baffle hot air interface, the upper wall of each baffle is evenly distributed with multiple baffle hot air holes; the nitrogen pipe is connected to the air inlet of the gas heater, the air outlet of the gas heater is connected to the hot air main pipe, and the hot air main pipe is respectively connected to the air inlet of the gas heater. The hot air branch pipes of each layer are connected, the hot air branch pipes of each layer and the cold air branch pipes of the same layer are connected to the baffle air supply pipe of the layer, and the outlet of the baffle air supply pipe of each layer is respectively connected with the baffle hot air of the layer The interface is connected.
The PBS-type biodegradable material production system according to claim 6, wherein the diameter of the upper end of the drying tower cone is larger than the diameter of the tower body, and the lower end of the tower body is inserted into the drying tower cone. In the upper port of the bucket, and the upper port of the drying tower cone is provided with an annular cover, the inner edge of the annular cover is welded to the outer wall of the tower body; the annular cavity below the annular cover The body is connected to the tower body air supply ring pipe through a plurality of evenly distributed radial connecting pipes. The tower body hot air inlet is provided on the circumference of the tower body air supply ring pipe, and the lower port of the tower body is connected to the tower body. Between the inner walls of the cone of the drying tower is provided an annular hot air channel with a downward opening.
[Corrected according to Rule 91 30.08.2021]
The production system of PBS-type biodegradable materials according to any one of claims 1 to 8, characterized in that: the gas phase of the first polycondensation kettle, the second polycondensation kettle, the final polycondensation reaction kettle or the viscosity-increasing reaction kettle The outlets are respectively connected to the side wall inlets of their respective vacuum traps, the top gas-phase ports of each vacuum trap are respectively connected to the air inlets of the scraper condenser, and the bottom outlets of each vacuum trap are respectively connected to the vacuum collection tank through an electric shut-off valve The top inlet of each vacuum collecting tank is connected, the top air inlet of each vacuum collecting tank is also connected to the nitrogen pipe through the collecting tank nitrogen valve, and the bottom of each vacuum collecting tank is provided with a collecting tank discharge valve; the medium outlet of each scraper condenser passes through the atmosphere. The legs are connected with respective hot wells, the liquid phase outlet of each hot well is connected with the inlet of the spray circulating pump, and the outlet of the spray circulating pump is connected with the spray outlet of the scraper condenser through a circulating liquid cooler.
[Corrected according to Rule 91 30.08.2021]
The PBS-type biodegradable material production system according to claim 9, characterized in that: the top of the hot well is provided with a top cover of the hot well, and a longitudinal partition is arranged along the longitudinal axis of the hot well to separate the inner cavity of the hot well It is the left and right halves. The middle section of the longitudinal partition is provided with left and right inner chambers symmetrically on both sides. The lateral wall of the left inner chamber is the left outer chamber, and the lateral wall of the right inner chamber is the right outer chamber. , The bottom of the left inner chamber and the right inner chamber are respectively provided with conical hoppers, the lowest part of the two conical hoppers are respectively connected with the hot well slag outlet, the two hot well slag outlets respectively extend downward to the bottom of the hot well The bottom of the left outer chamber and the right outer chamber are respectively provided with the liquid phase outlet of the hot well; the top cover of the hot well is inserted with two atmospheric legs, and the lower ends of the two atmospheric legs are respectively inserted into the left inner chamber and In the lower part of the inner cavity of the right inner chamber, the upper part of each horizontal wall plate is respectively provided with an overflow port communicating with the corresponding outer chamber, the inner port of each overflow port is covered with a filter plate, and the left and right sides of each filter plate are plugged in respectively In the vertical slot on the inner end surface of the horizontal wall panel, the outer port of each overflow port is respectively covered with a convex arc-shaped filter basket, and the left and right sides of each arc-shaped filter basket are respectively inserted into the Vertical slot.
[Corrected according to Rule 91 30.08.2021]
The PBS-type biodegradable material production system according to claim 10, wherein the hot well slag discharge port is respectively connected with the cleaning tank feed port on the top of the cleaning tank, and the cleaning tank includes a closed end. Type cylinder, the front port of the cleaning box is hinged with a cleaning box cover that can be opened and closed, the cylinder body of the cleaning box is covered with a cleaning box jacket, and the inner cavity of the cleaning box is set up There are a plurality of square filter drawers stacked one after another. The frames on the left and right sides of each square filter drawer are respectively supported by guide chutes by rollers. Each guide chute extends along the axial direction of the cleaning box and is fixed on the inner wall of the cleaning box. On both sides, the bottom of the inner cavity of the cleaning box is provided with an arc-shaped bottom drawer, the bottom of the arc-shaped bottom drawer is supported on the bottom of the inner wall of the cleaning box by rollers, and the bottom of the arc-shaped bottom drawer and each square filter drawer are respectively A filter screen is provided, and the mesh number of the lower filter screen is sequentially greater than the mesh number of the upper filter screen, the lower end of the feed opening of the cleaning box points to the center area of the top square filter drawer, and the bottom center of the cleaning box is provided with a cleaning box Drainage port.