Basic Studies on the Dual-Polymer Flocculation of Iron Hydroxide

The efficiency of synthetic flocculants in flocculation processes has been identified by several authors over the years, and this makes it applicable in the industry. Nowadays, studies are focused on the combination of polymers for optimal performance. In this study, the physicochemical conditioning of iron hydroxide suspension (obtained sludge from the lignite mined sites in the Lusatia region of Germany) was investigated with flocculants of different properties as single polymer conditioning (C492 and A130) and as dual-polymer conditioning (C492+N300, A130+N300 and C492+A130) using Jar test. C492 is a cationic flocculant, A130 is an anionic flocculant, and N300 is a non-ionic flocculant. Turbidity of the supernatant and the sludge volume index were the assessing parameters considered under dosage range of 0.4, 0.8, 1.2, 2.0, 2.8 and 3.6 mg/gTS. The obtained optimization results were compared to the actual separation with respect to specific filtration resistance from pressure filtration. The obtained results show some interesting differences which are discussed in this book.