环保型PTFE分散乳液真空浓缩工业技术研究

Research on Industrial Technology of Vacuum Concentration of Environmentally Friendly PTFE Dispersion Emulsion

PTFE分散乳液是PTFE固体颗粒在乳化剂作用下形成的具有一定稳定性的乳液产品,聚合得到的产品PTFE含量较低,需要进行浓缩,提高PTFE的含量。主要采用烷基酚聚氧乙烯醚类作为乳化剂,而壬基酚聚氧乙烯醚(NPEO)类物质使用量最多。传统的分散乳液浓缩过程是采用加入大量的NPEO乳化剂,搅拌分层后去除上清液的方法来达到浓缩效果,此方法不仅消耗大量NPEO乳化剂,增加了生产成本,而且产生的废液中含有大量的NPEO乳化剂,造成污水处理困难,同时污染环境。PTFE分散乳液真空浓缩是将少量的乳化剂与PTFE聚合分散液混合于浓缩釜中,使乳液在真空状态下蒸发的水分经消泡、气液分离、冷凝排入水封池中,以达到乳液浓缩的目的。

PTFE dispersion emulsion is an emulsion product with certain stability formed by PTFE solid particles under the action of emulsifier.The product obtained by polymerization has a low PTFE content and needs to be concentrated to increase the PTFE content.In the industry,alkylphenol polyoxyethylene ethers are mainly used as emulsifiers,while nonylphenol polyoxyethylene ether(NPEO)substances are used the most.The traditional dispersion emulsion concentration process is to add a large amount of NPEO emulsifier,stir and stratify and remove the supernatant to achieve the concentration effect.This method not only consumes a large amount of NPEO emulsifier,which increases the production cost,but also generates waste liquid.Contains a large amount of NPEO emulsifier,which makes sewage treatment difficult and pollutes the environment.The vacuum concentration of the PTFE dispersion emulsion studied in this paper is to mix a small amount of emulsifier with the PTFE polymerization dispersion in a concentration kettle,so that the water evaporated in the vacuum state is discharged into the water seal through defoaming,gas-liquid separation,condensation In the pool,to achieve the purpose of emulsion concentration.