Improvements in or relating to processes and apparatus for water softening

摘要

In a process for reducing the hardness of water, the precipitation and settling of the substances which impart hardness to the water is accelerated by bringing the water, immediately after addition of known precipitating agents, into contact with a contact substance as defined below, then removing the water from contact with the substance before any material amount of precipitate has been deposited, and leading it into settling tanks where the bulk of the precipitate is deposited. The contact substances employed are either (1) a carrier substance firmly coated with precipitated carbonate, the carrier substance being any solid which is insoluble in water, such as gravel or granite, and which is in the form of pieces or grains, or (2) marble, limestone, dolomite or a like carbonate insoluble in water. The contact substance may be placed in a container mounted between the measuring apparatus and the settling tank of an ordinary water-softening plant.ALSO:In a process for reducing the hardness of water, the precipitation and settling of the substances which impart hardness to the water are accelerated by bringing the water, immediately after addition of known precipitating agents, into contact with a contact substance as defined below, then removing the water from contact with the substance before any material amount of precipitate has been deposited, and leading it into settling tanks where the bulk of the precipitate is deposited. The contact substances employed are either (1) a carrier substance firmly coated with precipitated carbonate, the carrier substance being any solid which is insoluble in water, such as gravel or granite, and which is in the form of pieces or grains, or (2) marble, limestone, dolomite or a like carbonate insoluble in water. The contact substance may be placed in a container mounted between the measuring apparatus and the settling tank of an ordinary water-softening plant.