Automatic system for preparing lithium hydroxide

The invention provides an automatic system for preparing lithium hydroxide with low preparation cost. The automatic system for preparing lithium hydroxide, provided by the invention, comprises a preparation subsystem and is characterized by further comprising a protective air supply subsystem, a filtering device, a mother liquor storage device, an absorption tower, an air drying device and a feeding device, wherein the protective air supply subsystem is used for removing carbon dioxide from air so as to supply air free from carbon dioxide as protection air to the preparation technology of lithium hydroxide; the filtering device is used for filtering grains from air and comprises at least two filters, a valve component and a valve control unit; the remained lithium hydroxide mother liquor after crystal is separated from a concentrating crystallizing device is stored in the mother liquor storage device; the absorption tower introduces the lithium hydroxide mother liquor as an absorption agent for absorbing carbon dioxide in the filtered air so as to obtain the air free from carbon dioxide; the air drying device is used for drying the air free from carbon dioxide and obtaining the protective air; the feeding device is communicated with the air drying device and is used for feeding the protective air to the preparation subsystem.