Why are aluminum hydroxide crystals added as seed in Bayer process precipitators?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

aluminum processing Rolls of processed aluminum.

In the Bayer process, aluminum hydroxide crystals are added to the solution within the precipitators to act as seeding, which serves to hasten the separation of crystals from the liquid.1

These seed crystals function by attracting other crystals to form agglomerates. Once formed, these agglomerates are classified into two groups: larger material that becomes the final product and finer material that is recycled back into the process to serve as additional seed.1