Cleaning Methods of Plastic Fillers
Briefly introduces the cleaning methods for plastic fillers.
Cleaning Methods of Plastic Fillers
Prolonged use of plastic fillers can lead to increased pressure drop due to scaling and coking. Regular cleaning can restore performance. Plastics are not heat-resistant and must not be subjected to heat treatment.
Contaminants and Cleaning Methods
Contaminants | Cleaning Methods | Conditions |
Oil Stains | Alkaline washing (NaOH 2%-5%) | 60-80℃, 2-4 hours |
Scale/Salt Scale | Acid washing (Dilute hydrochloric acid 3%-10%) | Room temperature, 4-8 hours |
Biofilm | Sodium hypochlorite (0.5%-1%) | Room temperature, 2 hours |
Loose Sludge | High-pressure water rinsing | 5-10MPa |
After chemical cleaning, rinse with water until neutral.
Cleaning Method
Method | Applicable | Advantages | Disadvantages |
Online Cleaning | Lightly soiled | Short downtime (1-3 days) | Limited effectiveness |
Offline Cleaning | Heavily soiled | Thorough, can remove damaged parts | Long downtime (5-15 days) |
Differences from metal and ceramic cleaning
Comparison | Plastics | Metals | Ceramic |
Heat treatment | Not suitable | Suitable | Suitable |
Cleaning temperature | ≤80℃（PP） | Unlimited | Unlimited |
Strong acid cleaning | Suitable | Carbon steel not suitable | Suitable |
Precautions
Cleaning temperature should not exceed the upper temperature limit of the packing material (PP ≤ 80℃, PVDF ≤ 150℃).
PVC is not resistant to organic solvents, and PP is not resistant to strong oxidants.
For heavy oil stains, first perform alkaline washing, then acid washing, rinsing with water in between.
Remove deformed or damaged packing material during offline cleaning.
Cleaning should be scheduled when the pressure drop increases by more than 30%.
Summary
Plastic packing material cleaning can be summarized as: alkaline washing for oil stains, acid washing for scale, and strictly prohibiting heating. Offline cleaning is more thorough, while online cleaning results in shorter downtime. Pay attention to material compatibility and temperature limits; standardized cleaning is key to extending service life.