Pickouts Problem at Papermaking Process

There are many problems happened in the process of papermaking. One of the common problem appeared is the material pickouts in the paper machine. We can catagorized the material pickouts based on the location happened/source.

a. Pickouts from the wet-end press: This pickouts happened at the wet-end press.
There are several ideas to solve this problem, such as:
- Check the white water pH to ensure it is within spec
- Check the cleanliness of all presses, carrier rolls and fly rolls
- Add a surface tension-reducing agent to high pressure cleaning shower water
- (Too) high moisture content in the web entering the press section
- Check the presses and felts for pitch build up

b. Pickouts from the dryers: This pickouts happened at the dryer section.
There are several ideas to solve this problem, such as:
- Check the temperatures in the lead-in dryers to be sure the temperatures are properly graduated
- Check for worn or damaged dryer felts

c. Pickouts from the size press: This pickouts happens at the size press.
There are several ideas to solve this problem, such as:
- Check any damage on the size press filters or screens. Starch contamicated with fibers and dust contributes to pick-outs
- Clean the size-press showers to eliminate the build of starch

d. Pickouts from the stock additives
There are several ideas to solve this problem, such as:
- Improperly cooked or mixed aditives such as gum, starch, retention agents, defoamers, etc. will contribute to pickouts