提高氯乙烯悬浮聚合釜的生产能力
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摘要
长期以来，高消耗、低效率一直制约着我国聚氯乙烯(PVC)行业的发展，其中聚合过程是主要的影响环节。国外从20世纪末已不再依靠增添聚合釜数量、一味追求聚合釜大型化提高PVC产量，而转为优化生产过程、提高生产效率，单釜生产强度增至300t／a·m~3。巨化公司电化厂采用悬浮法生产PVC树脂已有30多年历史，生产工艺技术成熟，拥有7台LF-Ⅱ型30m~3聚合釜，单釜生产能力约为5000t／a，生产强度仅167t／a·m~3，与国外先进生产装置的生产强度相差甚远。扩建新增的LF-Ⅳ型和LF-Ⅱ型两台30m~3釜是重蹈覆辙、还是革新增效，急待解决。本文从巨化电化厂PVC生产实际出发，以提高30m~3氯乙烯(VC)悬浮聚合釜的生产能力为目标，分析制约提高生产能力的因素，提出了应用高效复合引发体系以缩短聚合反应时间；建立密闭投料新工艺以减少辅助生产时间；使用新型防粘釜剂以延长清釜周期以及增加VC投料量以提高产量等措施，经工业化试生产效果明显，有较好的推广前景。
提高反应速度、减少聚合时间，引发剂是关键。本文按照引发剂的选择原则，运用复合引发剂存在下的VC悬浮聚合动力学模型，以5小时聚合时间为例，进行缩短聚合反应时间的引发剂配方设计，对51、57、62℃下的VC悬浮聚合动力学进行预测，经小试考核模型值与实验值吻合较好。结果表明，在51℃，EHP与Tx99引发剂复合，57℃下EHP与Tx 23、Tx 36引发剂复合，62℃下Tx 23与Tx 36引发剂复合都可将聚合时间缩短为4～4.5小时。
最大聚合速率与聚合釜传热能力的均衡是达到缩短聚合时间、提高生产能力的重要环节。通过传热的理论计算、冷模测试和聚合考核，8~#(LF-Ⅳ)聚合釜设置有半园管夹套，冷模平均传热系数(993kcal／m~2·℃·hr)和聚合传热系数(800kcal／m~2·℃·hr)都比较大，能满足将聚合反应时间缩短至4.5～5小时的要求；3~#(LF-Ⅱ)聚合釜虽然设置普通螺旋档板夹套并已使用了12年之久，但除水垢后仍有较高传热能力(冷模：750kcal／m~2·℃·hr；聚合：650kcal／m~2·℃·hr左右)，也能满足缩短聚合反应时间的需要。两釜型的搅拌动力特性(0.90～0.98kw／m~3)和循环次数(6.1～8.9次／分)均能满足PVC生产的要求。
将复合引发剂的VC聚合动力学与30m~3聚合釜的传热能力相偶合，优化了缩短聚合时间的引发剂三配方，并在30m~3釜进行工业化聚合试验，考核聚合动力
浙江人学硕七学位论文
学、聚合釜传热能力和树脂质量。与原聚合配方相比，使用试验配方一、三进行生
产时节省聚合反应时间45~50分钟;使用试验配方二进行生产时，可节省聚合反
应时间约80分钟。PVC树脂质量均符合国家标准。
减少辅助生产时间也是提高聚合釜生产能力的关键。本文在完善聚合全过程集
散控制(DCS)系统之后，建立密闭、连续、自动投料新工艺，使用新型防粘釜剂，
增力f!vc投料量(减少水油比、增大投料系数)等，并在巨化公司电化厂30砰釜进
行工业化试生产，VC聚合辅助生产时间平均节省约2小时。
综合缩短聚合反应时间和减少辅助生产时间两者效果，每釜可缩短生产时间
3.5小时，整个生产周期可降至8小时左右。经72小时装置能力测试，9台釜产量
达到660t。从而使巨化公司电化厂301矿聚合釜单釜生产能力由so00t/a提高到
8000t/a，单釜生产强度由167t/a·m3增至270t/a·m3，接近于国外先进水平。目
前，该研究成果已在巨化公司电化厂全面实施，提高了聚合釜的生产能力，降低了
树脂成本，为企业在市场竞争中打下坚实的基础，也可在国内PVC行业推广应
用。
The development of PVC industry is restricted by the higher cost and lower efficiency in our country for a long time. The polymerization process is the main influencing factor. To optimize the producing process and to improve the production efficiency have became the main approach to improve the production capacity of PVC for companies in foreign countries. Juhua Electric-chemical Factory has produced suspension PVC resin for more than 30 years and possess matured production technology and 7 LF-II type 30m3 polymerization reactors. The production capacity of each reactor is about 5000t/a or 167t/a m3. The significant difference is existed between Juhua's devices and foreign advanced devices in production capacity. Base on the production practices of Juhua Electric-chemcial Company and aiming to improve the production capacity of 30 m3, the factors affecting the production capacity was analyzed and it was proposed to shorten the polymerization time by using of composite initiator system, to shorten the auxil
iary production time by setting up of close feeding technology, to prolong the reactor cleaning period by using of new anti-scale agent and to improve the production by increasing the feeding weigh of VC. The industry experimental production showed good results and it exhibits good application prospect.
The initiator is the key to increase the reaction rate and to shorten the polymerization time. According to the rule for choosing initiator and applying the kinetics model of VC suspension polymerization initiated by the composite initiator system, the initiator recipe was designed to shorten polymerization time to be 5h. The kinetics was predicted for VC suspension polymerization carried out at 51,57 and 62. The model values were fitted well with experimental values. It showed that the polymerization time could be shorten to be 4~4.5h by using the composite of EHP and TX99 at 51 , the composite of EHP,TX23 and TX36 at 57掳C, and the composite of TX23 and TX36 at 62 , respectively.
The balance between the maximum reaction rate and the heat transfer capacity of the reactor was the key factor for shortening of polymerization time and improving the production capacity. The theoretical calculation, cold reactor measurement and polymerization examination showed that the average heat transfer coefficient with no polymerization (993kcal/m2 hr) and the average heat transfer coefficient during the polymerization (800kcal/m2 hr) of No.8 (LF-IV type, with semi-circle tube
jacket) reactor were greater, and it could be satisfied the requirement for shortening of polymerization time to be 4.5~5h. Although No.3 reactor was equipped with helix baffle jacket and had used for more than 12 years, it still exhibited higher heat transfer capacity (750kcal/m2 hr and 650kcaJ/m2 hr in cases of with no polymerization and during polymerization) and could be satisfied the need of shorting polymerization time if the incrustation was removed. The agitation dynamic property (0.90~0.9SKW/m3) and circular number (6.1~8.9/min) could be satisfied the requirement of PVC production.
Combining with the kinetics of VC polymerization initiated by the composite initiator system and the heat transfer capacity of 30m3 reactor, three optimized initiator recipes were obtained and applied in 30m3 reactor polymerizations. The polymerization kinetics, heat transfer capacity and the quality of the resulting PVC resins were examined. Comparing with the original polymerization recipe, the polymerization time could be shortened 40-~45min by applying No.l and No.3 recipes, and shortened 80min by applying No.2 recipe. The quality of the obtained PVC resins was all satisfied the corresponding national standard.
It was also important to shorten the auxiliary production time. By setting up of the close, continuous and automatic feeding technology after perfecting the DSC control system and using of the new anti-scale agent, the auxiliary time of VC polymerization was shorten 2h.
Combining with the shortening of polymerization time and auxili
提高反应速度、减少聚合时间，引发剂是关键。本文按照引发剂的选择原则，运用复合引发剂存在下的VC悬浮聚合动力学模型，以5小时聚合时间为例，进行缩短聚合反应时间的引发剂配方设计，对51、57、62℃下的VC悬浮聚合动力学进行预测，经小试考核模型值与实验值吻合较好。结果表明，在51℃，EHP与Tx99引发剂复合，57℃下EHP与Tx 23、Tx 36引发剂复合，62℃下Tx 23与Tx 36引发剂复合都可将聚合时间缩短为4～4.5小时。
最大聚合速率与聚合釜传热能力的均衡是达到缩短聚合时间、提高生产能力的重要环节。通过传热的理论计算、冷模测试和聚合考核，8~#(LF-Ⅳ)聚合釜设置有半园管夹套，冷模平均传热系数(993kcal／m~2·℃·hr)和聚合传热系数(800kcal／m~2·℃·hr)都比较大，能满足将聚合反应时间缩短至4.5～5小时的要求；3~#(LF-Ⅱ)聚合釜虽然设置普通螺旋档板夹套并已使用了12年之久，但除水垢后仍有较高传热能力(冷模：750kcal／m~2·℃·hr；聚合：650kcal／m~2·℃·hr左右)，也能满足缩短聚合反应时间的需要。两釜型的搅拌动力特性(0.90～0.98kw／m~3)和循环次数(6.1～8.9次／分)均能满足PVC生产的要求。
将复合引发剂的VC聚合动力学与30m~3聚合釜的传热能力相偶合，优化了缩短聚合时间的引发剂三配方，并在30m~3釜进行工业化聚合试验，考核聚合动力
浙江人学硕七学位论文
学、聚合釜传热能力和树脂质量。与原聚合配方相比，使用试验配方一、三进行生
产时节省聚合反应时间45~50分钟;使用试验配方二进行生产时，可节省聚合反
应时间约80分钟。PVC树脂质量均符合国家标准。
减少辅助生产时间也是提高聚合釜生产能力的关键。本文在完善聚合全过程集
散控制(DCS)系统之后，建立密闭、连续、自动投料新工艺，使用新型防粘釜剂，
增力f!vc投料量(减少水油比、增大投料系数)等，并在巨化公司电化厂30砰釜进
行工业化试生产，VC聚合辅助生产时间平均节省约2小时。
综合缩短聚合反应时间和减少辅助生产时间两者效果，每釜可缩短生产时间
3.5小时，整个生产周期可降至8小时左右。经72小时装置能力测试，9台釜产量
达到660t。从而使巨化公司电化厂301矿聚合釜单釜生产能力由so00t/a提高到
8000t/a，单釜生产强度由167t/a·m3增至270t/a·m3，接近于国外先进水平。目
前，该研究成果已在巨化公司电化厂全面实施，提高了聚合釜的生产能力，降低了
树脂成本，为企业在市场竞争中打下坚实的基础，也可在国内PVC行业推广应
用。
The development of PVC industry is restricted by the higher cost and lower efficiency in our country for a long time. The polymerization process is the main influencing factor. To optimize the producing process and to improve the production efficiency have became the main approach to improve the production capacity of PVC for companies in foreign countries. Juhua Electric-chemical Factory has produced suspension PVC resin for more than 30 years and possess matured production technology and 7 LF-II type 30m3 polymerization reactors. The production capacity of each reactor is about 5000t/a or 167t/a m3. The significant difference is existed between Juhua's devices and foreign advanced devices in production capacity. Base on the production practices of Juhua Electric-chemcial Company and aiming to improve the production capacity of 30 m3, the factors affecting the production capacity was analyzed and it was proposed to shorten the polymerization time by using of composite initiator system, to shorten the auxil
iary production time by setting up of close feeding technology, to prolong the reactor cleaning period by using of new anti-scale agent and to improve the production by increasing the feeding weigh of VC. The industry experimental production showed good results and it exhibits good application prospect.
The initiator is the key to increase the reaction rate and to shorten the polymerization time. According to the rule for choosing initiator and applying the kinetics model of VC suspension polymerization initiated by the composite initiator system, the initiator recipe was designed to shorten polymerization time to be 5h. The kinetics was predicted for VC suspension polymerization carried out at 51,57 and 62. The model values were fitted well with experimental values. It showed that the polymerization time could be shorten to be 4~4.5h by using the composite of EHP and TX99 at 51 , the composite of EHP,TX23 and TX36 at 57掳C, and the composite of TX23 and TX36 at 62 , respectively.
The balance between the maximum reaction rate and the heat transfer capacity of the reactor was the key factor for shortening of polymerization time and improving the production capacity. The theoretical calculation, cold reactor measurement and polymerization examination showed that the average heat transfer coefficient with no polymerization (993kcal/m2 hr) and the average heat transfer coefficient during the polymerization (800kcal/m2 hr) of No.8 (LF-IV type, with semi-circle tube
jacket) reactor were greater, and it could be satisfied the requirement for shortening of polymerization time to be 4.5~5h. Although No.3 reactor was equipped with helix baffle jacket and had used for more than 12 years, it still exhibited higher heat transfer capacity (750kcal/m2 hr and 650kcaJ/m2 hr in cases of with no polymerization and during polymerization) and could be satisfied the need of shorting polymerization time if the incrustation was removed. The agitation dynamic property (0.90~0.9SKW/m3) and circular number (6.1~8.9/min) could be satisfied the requirement of PVC production.
Combining with the kinetics of VC polymerization initiated by the composite initiator system and the heat transfer capacity of 30m3 reactor, three optimized initiator recipes were obtained and applied in 30m3 reactor polymerizations. The polymerization kinetics, heat transfer capacity and the quality of the resulting PVC resins were examined. Comparing with the original polymerization recipe, the polymerization time could be shortened 40-~45min by applying No.l and No.3 recipes, and shortened 80min by applying No.2 recipe. The quality of the obtained PVC resins was all satisfied the corresponding national standard.
It was also important to shorten the auxiliary production time. By setting up of the close, continuous and automatic feeding technology after perfecting the DSC control system and using of the new anti-scale agent, the auxiliary time of VC polymerization was shorten 2h.
Combining with the shortening of polymerization time and auxili
引文
【1】潘祖仁等，塑料工业手册(聚氯乙烯)，北京：化学工业出版社，1999．
【2】潘祖仁等，氯乙烯聚合化学和聚合工程基础研究究论文集，1988．10
【3】杨勇靖，过氧化物复合引发剂分解动力学研究及应用，浙江大学硕士学位论文，1998
【4】单国荣、翁志学、黄志明、潘祖仁，聚氯乙烯，2000，(1)：31～34
【5】单国荣、翁志学、黄志明、潘祖仁，高等学校化学学报，2000，21(11)：1779～1781
【6】单国荣、翁志学、黄志明、潘祖仁，高等学校化学学报，2000，21(12)：1928～1931
【7】潘祖仁等，自由基聚合，北京：化学工业出版社，1983
【8】潘祖仁，高分子化学(第三版)，北京：化学工业出版社，2002
【9】王伯英等，聚氯乙烯大全，北京：化学工业出版社，1987
【10】严祸英等，聚氯乙烯工艺学，北京：化学工业出版社，1990
【11】Xie, T.Y., Hemielec, A.E., Wood, P.E., Wood, D.R., J.Vinyl Tech., 13(1): 2～4
【12】郑石子等，聚氯乙烯生产过程及操作，北京：化学工业出版社1993
【13】潘祖仁、单国荣、翁志学、黄志明，Chinese.J of Chem.Eng., 2001，9(1)：1～4
【14】黄志明等，聚氯乙烯，2001，(5)：5～8-21
【15】潘祖仁、单国荣、翁志学、黄志明，Proceedings Third Joint China／USA Chemical Engineering Conference，Sept25～28，2000，Beijing China，10-08-12
【16】蓝凤祥，聚氯乙烯，2000，(6)：1～20
【2】潘祖仁等，氯乙烯聚合化学和聚合工程基础研究究论文集，1988．10
【3】杨勇靖，过氧化物复合引发剂分解动力学研究及应用，浙江大学硕士学位论文，1998
【4】单国荣、翁志学、黄志明、潘祖仁，聚氯乙烯，2000，(1)：31～34
【5】单国荣、翁志学、黄志明、潘祖仁，高等学校化学学报，2000，21(11)：1779～1781
【6】单国荣、翁志学、黄志明、潘祖仁，高等学校化学学报，2000，21(12)：1928～1931
【7】潘祖仁等，自由基聚合，北京：化学工业出版社，1983
【8】潘祖仁，高分子化学(第三版)，北京：化学工业出版社，2002
【9】王伯英等，聚氯乙烯大全，北京：化学工业出版社，1987
【10】严祸英等，聚氯乙烯工艺学，北京：化学工业出版社，1990
【11】Xie, T.Y., Hemielec, A.E., Wood, P.E., Wood, D.R., J.Vinyl Tech., 13(1): 2～4
【12】郑石子等，聚氯乙烯生产过程及操作，北京：化学工业出版社1993
【13】潘祖仁、单国荣、翁志学、黄志明，Chinese.J of Chem.Eng., 2001，9(1)：1～4
【14】黄志明等，聚氯乙烯，2001，(5)：5～8-21
【15】潘祖仁、单国荣、翁志学、黄志明，Proceedings Third Joint China／USA Chemical Engineering Conference，Sept25～28，2000，Beijing China，10-08-12
【16】蓝凤祥，聚氯乙烯，2000，(6)：1～20