A method for dewatering a slurry of solid particles suspended in a liquid using a twin belt press dewatering system, comprising the following steps:feeding the slurry of solid particles into the dewatering system;feeding a cationic amine salt solution into the dewatering system at a point just prior to the mixing drum, the cationic amine salt being a latex copolymer of acrylamide and dimethylaminoethylmethacrylate sulfuric acid salt having a mole ratio in the range between about 30:70 to 70:30, preferably 53:47;mixing the cationic amine salt solution with the slurry of solid particles in the mixing drum; andfeeding the cationic amine salt solution/slurry mixture to the twin belt press, whereby the slurry of solid particles is dewatered. The cationic amine salt solution having a strength of less than 1% and a polymer concentration of about 35%.