A novel coagulant agent from Acacia mearnsii de Wild tannin extract was characterized for removal of the anthraquinonic colorant Alizarin Violet 3R and the anionic surfactant sodium dodecylbenzene sulfonate. This coagulant is the result of a previous optimization study. The influence of operative variables such as temperature, coagulant dosage, initial pollutant content, and pH was investigated. The new coagulant demonstrates a high affinity for dye and surfactant and is efficient within a wide range of working conditions. While the temperature does not affect the coagulant ability, an acidic pH seems to increase the contaminant removal from aqueous solutions. Implementation in a pilot plant confirms the feasibility of this coagulant not only at lab scale, but also at higher level.