Compacted polyhalite and a process for the production thereof

There is provided herein a process for the compaction of Polyhalite, comprising: mixing a feed of polyhalite with an inorganic binder in a mixer to yield a mixture; compacting said mixture in a compactor to yield masses; crushing said masses in a crusher to yield particles; and screening said particles in a screener to yield particles in three different sizes: oversized fine particles which undergo a second crushing process and are retuned to said screener for screening, undersized fine particles which are transferred to said mixer for further mixing and compacting, and desired size fine particles which are transferred to a polish screener for glazing and oiling.