1. Black liquid for papermaking can be directly used in stock solution, and other waste water can be diluted according to the need. It is recommended to be prepared into a concentration of not less than 10%. 2. The best dosage should be determined according to the experiment. 3. Less than 10% of the liquid medicine to be prepared on the same day, the day used up, not retained. 4. Use clean water to prepare liquid medicine. When using reclaimed water, a small amount of precipitation is a normal phenomenon.