Abstract: A system for producing particles of basic aluminum chloride includes a liquid feed system configured to have a liquid solution of aluminum chloride and configured to dispense droplets of the liquid solution, the droplets having an average size of about 0.5 mm to about 15 mm in diameter and spaced apart from one another, at least one conveyor belt having a surface configured to hold the droplets, a first heating zone having at least one radiant heat source configured to heat the liquid solution on the surface to concentrate the aluminum chloride, and a second heating zone having at least one radiant heat source configured to heat the concentrated aluminum chloride to decompose the aluminum chloride and produce the particles of basic aluminum chloride. The method includes dispensing and heating the droplets in a particular way to produce the particles of the basic aluminum chloride.

Abstract: An improved method for preparing a basic aluminum hyrdoxy-chlorosulfate is disclosed comprising reacting a basic aluminum chloride with a sulfate source, i.e. H.sub.2 SO.sub.4 or aluminum sulfate, and modifying the reaction product by the addition of minor amounts of calcium containing compound and a water soluble iron salt. The product is useful in water treatment, is effective in cold water as well as low alkalinity water. A magnesium compound can be added to the composition where the calcium source contains no magnesium.