The invention provides methods and compositions for improving the production of alumina hydrate. The invention involves adding one or more cross-linked ethylsulfonated polysaccharides to liquor or slurry in the fluid circuit of the production process. The one or more polysaccharides include cross-linked dextran or cross-linked dihydroxypropyl cellulose. The various polysaccharides can impart a number of advantages including at least some of: greater flocculation effectiveness, increasing the maximum effective dosage, faster settling rate. The production process can be a Bayer process.