1. Heating method; Cooling method 2. Adjust the pH value of the suspension; 3. Agglomeration and flocculation (1) Agglomeration refers to the process of adding a certain electrolyte to a colloidal suspension. Under the action of electrolyte ions, the double layer potential of colloidal particles decreases, causing the colloid to lose stability and causing particles to aggregate into block like aggregates of about 1mm in size. (2) Flocculation refers to the process of using coagulants to crosslink colloidal particles into a network, forming flocs of approximately 10mm in size. The flocculant mainly plays a bridging role. 4. Add filter aid; 5. Add reactants; 6. Other methods