The large-scale polymeric kettle of suspension polymerization of VC
(1) technical field
The utility model relates to a kind of polymeric kettle, specifically relates to a kind of large-scale polymeric kettle of suspension polymerization of VC.
(2) background technology
In the Production of PVC process, polymeric kettle is main production unit, and the quality of its technical feature directly has influence on the economy etc. of output, quality and the operation of polyvinyl chloride.At present, the home-made pvc polymerizer has only 70m
3, 48m
3, 30m
3, 13.5m
3And 7m
3Several medium and small still types.These middle-size and small-size polymeric kettle unit volume output are little, the energy consumption height, and also counter investment is big, and production efficiency is low, has been superseded gesture.Along with the polyvinyl chloride industrial expansion, the chloroethylene polymerization still also towards most economical, production efficiency is high, construction cost and maintenance cost is low, good product quality, direction that output is big develop.It is support that Jinxi Chemical Machinery (Group) Co., Ltd. produces 400000 tons of polyvinyl chloride projects per year with Sinopec Shandong branch office, has developed LF135 type pvc polymerizer.The polymeric kettle of this model does not have finished product at present both at home and abroad.
In the suspension polymerization of VC process, exist problems such as sticking still, product particle is inhomogeneous, heat transfer is poor always, have a strong impact on the quality of polyvinyl chloride product; Particularly sticking still is an open question all the time in the Production of PVC, in the general Production of PVC process, all will clean still after the polymerization each time, influences the performance of polymeric kettle throughput.And the generation of the problems referred to above, remove have with polymerization technique outside the Pass, also with the structure of polymeric kettle, comprise that the design of support equipment is relevant.
The general polymerization still adopts the cooling of cooling jacket form, conventional jacket, spiral stream guidance type chuck, semicanal spiral chuck are arranged, conventional jacket has no longer been adopted in the design of polymeric kettle at present, because water coolant is entered by the chuck end opening, through the chuck ring go straight up to and on, overflow by suitable for reading, flow velocity is very low, turbulent extent is not enough, the cooling performance extreme difference.Though adopting the spiral chuck to conduct heat makes moderate progress, processing preferably under the situation, can obtain big flow velocity (2~3m/S), thereby improve heat-transfer effect significantly, be more satisfactory method of cooling, but because of being subject to processing the restriction of manufacturing, water coolant is walked " short circuit " easily, make heat transfer coefficient low, so the method for cooling of polymeric kettle also have much room for improvement.
(3) summary of the invention
The technical problems to be solved in the utility model provides a kind of production efficiency height, the large-scale polymeric kettle of the suspension polymerization of VC that build, operation and maintenance cost is low, output is big.
The technical scheme that adopts is:
The large-scale polymeric kettle of suspension polymerization of VC comprises kettle, transmission mechanism, agitator and polyreaction Controlling System.The volume of kettle is 110--145m
3, length-to-diameter ratio is that 1.92--2.15, nominal diameter are that 3.5--4.6 rice, kettle height are 7--15 rice.Be installed with the spirrillum semicanal on the kettle direct tube section outer wall, be installed with the spirrillum semicanal on the autoclave body bottom end socket outer wall.Condenser and the quick opening manhole that has interlocking gear are installed at the kettle top.Cold sleeve pipe in being equiped with in kettle, interior cold telescopic lower end stretch out on the kettle part and are equiped with water-in and water outlet.In kettle, be equiped with agitator.Agitator is made of the stirring rake that is installed on the stir shaft, and stirring rake is three layer of two leaf oar formula stirring rake.Transmission mechanism comprises motor, torque converter, step-down gear.Motor output shaft is connected with the input shaft of torque converter by shaft coupling, and the output shaft of torque converter is connected with the input shaft of step-down gear by shaft coupling.The output shaft of step-down gear is connected with the stir shaft of agitator by shaft coupling.Motor, torque converter, step-down gear are supported by the support that is fixed on the kettle top.
Above-mentioned stir shaft is provided with long key, in order to adjust the wording depth between agitator.
Above-mentioned speed reducer output shaft is connected with minor axis by shaft coupling, and the minor axis the other end is connected with the mechanical seal that is installed in the stir shaft upper end.
Above-mentioned polyreaction Controlling System adopts the DCS Controlling System.
Above-mentioned stir shaft is supported by the supporting mechanism that is arranged at the bottom of the still.This supporting mechanism comprises the base bearing that has the tuningout structure, and base bearing is provided with can be from the water-in of water filling between axle sleeve and the bearing shell.
Polymeric kettle length-to-diameter ratio of the present utility model is moderate, and unit volume output is big, can reach 438 tons/(cubic meter year).The utility model adopts three layer of two leaf paddle stirrer, and its stirring intensity shearing force and cycle index are more moderate, and product pellet is concentrated and even; The utility model adopts the top-extending type transmission mechanism, stable drive, running period is long, so heat-transfer effect is good, adopt polymeric kettle of the present utility model and explained hereafter polymerizing vinyl chloride, can obtain that particle form is good, even molecular weight distribution, higher, the black yellow point of oil absorbency and the few high-quality polyvinyl chloride product of brilliant point.And continuous production and still clearly.The successful Application of the utility model and corresponding technology is for China's PVC industry production has increased a new reator kind, with the development that promotes that China PVC produces.
(4) description of drawings
Fig. 1 is the structural representation of a kind of embodiment of the present utility model.
Fig. 2 is the utility model transmission structures synoptic diagram.
Fig. 3 is the kettle synoptic diagram that is equiped with the spirrillum semicanal.
Fig. 4 is agitator local structure synoptic diagram.
Fig. 5 is the blade structural representation.
Fig. 6 is interior cold sleeve pipe synoptic diagram.
Fig. 7 is a base bearing structural representation of the present utility model.
Fig. 8 pushes up the condenser of installing and opens the entrance structure synoptic diagram soon for kettle.
(5) embodiment
The large-scale polymeric kettle of suspension polymerization of VC comprises kettle 1, transmission rig, agitator and polyreaction DCS Controlling System.Kettle 1 length-to-diameter ratio is 2.3; Kettle 1 volume is 137m
3Kettle 1 nominal diameter is 4.2 meters; Kettle 1 highly is 15 meters; Be installed with spirrillum semicanal 3 on the direct tube section outer wall of kettle 1, on the bottom outer wall of kettle 1, be installed with spirrillum semicanal 16 (as Fig. 1, shown in Figure 3).Setting firmly the jacket structured water coolant that makes of spiral semicanal type on the cylindrical shell cooling employing cylindrical shell of the present utility model rises along the semicanal spiral, can obtain big flow velocity 4m/s with the little water yield, be the mode of many imports and multiple exit, improved heat transfer coefficient better, heat transfer coefficient can reach K=900W/ (m
2K), be 1.4 times of spiral deflector chuck, both improved heat transfer coefficient, increase the intensity of kettle again, lower cover also adopts the spiral half-pipe jacket, and intake-outlet is set.Effectively avoid " short circuit " phenomenon of water coolant.Be provided with condenser 7 at the top of kettle 1, condenser 7 is connected (see figure 8) by condenser interface 24 with the roof of kettle 1.Also be equiped with at the top of kettle 1 and open inlet 23 soon.Cold sleeve pipe 5 in kettle 1, being equiped with, kettle 1 is stretched out in the lower end of interior cold sleeve pipe 5, and interior cold sleeve pipe lower end is equiped with water-in 17 and water outlet 18.Interior cold sleeve pipe carries out the interior heat transfer of still, to remedy the deficiency of chuck heat transfer area, adopts carbon steel chromium plating design to make heat-transfer effect better, and generally interior cold telescopic wall thickness is thinner, its hot COEFFICIENT K=930~1163W/ (m
2K), interior cold telescopic heat transfer area is 10% of a chuck heat transfer area, but conducts 20% of polymerization reaction heat, and cold telescopic heat transfer efficiency is than chuck height in illustrating.Interior cold sleeve pipe employing is removable, is convenient to maintenance, cleans and extract out conveniently, and interior in addition cold sleeve pipe plays the effect of baffle plate in still, cooperate agitator to make shearing action moderate, obtains cycling stream up and down, and reaction is evenly carried out; Be suitable for solid particulate below 10 orders, concentration is not more than 50%, the chloroethylene polymerization of viscosity below 100 centipoises.Be equiped with agitator in kettle 1, agitator comprises stir shaft 8, stirring rake 4, and stirring rake is three layer of two leaf oar formula stirring rake (see figure 5), and diameter of propeller blade and kettle diameter ratio are 0.49, and stir shaft 8 is provided with long key 19.Long key 19 is set can be by producing the wording depth that needs to adjust between agitator.At the bottom of the still of kettle 1, be equiped with the stir shaft supporting device, comprise the base bearing 6 that is equiped with the tuningout core structure.Base bearing 6 is provided with can be from the water-in 22 of water filling between axle sleeve 20 and the bearing shell 21.Base bearing 6 supporting stir shafts 8.The installing adjusting deviation device, the off-centre of stir shaft lower end in the time of can effectively avoiding always assembling.During general chloroethylene polymerization, axle sleeve and bearing shell produce heat of friction when equipment operation, and material enters easily and because local superheating produces the plasticizing sheet, with stir shaft " locking ", is difficult to cleaning.The utility model is equiped with water-in 22 at the bottom of still, be furnished with waterflood pump and carry out continuous water filling, and water is entered between axle sleeve and bearing shell, and material is sealed, and has overcome the seize problem, and plays local refrigerative effect (see figure 7).
Transmission mechanism 2 of the present utility model adopts the top-extending type transmission mechanism, comprises motor 15, torque converter 14, step-down gear 13, shaft coupling 12, mechanical seal 9.Motor 15 output shafts are connected by the input shaft of shaft coupling with torque converter 14, and the output shaft of torque converter 14 is connected by the input shaft of shaft coupling with step-down gear 13.The output shaft of step-down gear 13 is connected with an end that connects axle that is supported by plumer block 11 neck bearings by shaft coupling 12, this the other end that connects axle is connected with an end of minor axis 10 by shaft coupling, and minor axis 10 the other ends are connected (see figure 2) with mechanical seal 9 on being installed in stir shaft.Motor 15, torque converter 14, step-down gear 13 are supported by the support 25 that is fixed on kettle 1 top.
The DCS Controlling System is adopted in polyreaction control, is known technology.The polymeric temperature realizes DCS Controlling System automatization control, in conjunction with the above-mentioned type of cooling, the polymeric kettle temperature variation can be controlled at ± 0.1--0.2 ℃ scope in, the heat transfer property of still is good, phenomenons such as overtemperature is uncontrollable can not occur.