①Sampling in sections to find the source.
Such impurities may be generated in key parts of polymerization, steam stripping, and drying equipment. Samples are taken from the bottom of the polymerization vessel, the outlet of the stripping tower, the first and second stages of the drying bed, and the location of the impurities is determined by microscope observation and analysis, based on production experience. , And take corresponding measures: if it occurs in the polymerization kettle, consider cleaning the kettle in advance or increasing the flushing volume; if it occurs in the first stage of the drying bed, reduce the centrifuge feed volume, increase the fan air volume or reduce the bed temperature.
②Strengthen the washing after discharging the polymerizer.
Sticking to the kettle and stirring and self-aggregation will cause the plastic compound to enter the next kettle reaction, which will increase the number of black and yellow spots and “fish eyes”. In view of this problem, the technical transformation of the electric spray valve of the polymerizer can be selected to increase the flushing pressure of the reactor wall, and through the up and down expansion of the nozzle, flushing without dead corners is realized, which alleviates the sticking of the reactor and completely solves the problem of self-aggregation.
③ Refined control and reasonable cleaning plan.
After the stripping and drying device has been running for a period of time, problems such as material accumulation in the stripping tower and sticky materials in the drying bed pipes will occur, which will directly cause the PVC particles to be baked at high temperature and change color. According to the production experience, make an inspection plan, arrange a special person to carry out the inspection on a periodic basis, and if an abnormality is found, immediately schedule a tower or bed washing operation to ensure the smooth operation of the device.