There is provided herein a granule of potash and polyhalite comprising: at least 10% Potash; at least 10% Polyhalite; optionally a binder; and wherein said granule comprises a bulk density of at least 1 T/m.sup.3 and single strength of between 1-5 kg/granule.

The present invention relates to a fertilizer in granular form comprising within the same granule a mixture of: (A) From 15 to 85 wt % of a potassium sulfate; and (B) From 85 to 15 wt % of at least one salt that is different from (A) and that provides potassium and/or magnesium and/or calcium and/or sulfate; wherein the fertilizer in granular form has—a potassium level (expressed as K2O) of at least 18 wt %, preferably at least 20 wt %;—a chloride level of at most 10 wt %, preferably at most 5 wt %, more preferably at most 3 wt %;—a magnesium level (expressed as MgO) of at most 10 wt %, preferably at most 9.5 wt %. Materials of the invention are free flowing & combine a good nutrient balance with a good hardness and wear resistance.

The present invention relates to a fertilizer in granular form comprising within the same granule a mixture of: (A) From 15 to 85 wt % of a potassium sulfate; and (B) From 85 to 15 wt % of at least one salt that is different from (A) and that provides potassium and/or magnesium and/or calcium and/or sulfate; wherein the fertilizer in granular form has—a potassium level (expressed as K2O) of at least 18 wt %, preferably at least 20 wt %;—a chloride level of at most 10 wt %, preferably at most 5 wt %, more preferably at most 3 wt %;—a magnesium level (expressed as MgO) of at most 10 wt %, preferably at most 9.5 wt %. Materials of the invention are free flowing & combine a good nutrient balance with a good hardness and wear resistance.

According to some embodiments there is provided a process for the recovery of SOP from Sulphate bearing mineral and Carnallite or Sylvenite, comprising: Dissolving Carnallite in water to obtain Sylvenite and high Magnesium Chloride brine; Adding Sodium Sulphate to said Carnallite to produce mixture of Kainte\Leonite, KCl and NaCl precipitant and brine containing Mg Cl.sub.2, KCl, NaCl; Separating the NaCl from the mixture; Obtaining a precipitant mixture of Leonite with KCl; Filtering said Leonite and washing with water to yield pure mixture of Leonite with KCl; Adding KCl to the Leonite with the KCl; and Decompose said Leonite with the KCl to SOP.

According to some embodiments there is provided a process for the recovery of SOP from Sulphate bearing mineral and Carnallite or Sylvenite, comprising: Dissolving Carnallite in water to obtain Sylvenite and high Magnesium Chloride brine; Adding Sodium Sulphate to said Carnallite to produce mixture of Kainte\Leonite, KCl and NaCl precipitant and brine containing Mg Cl.sub.2, KCl, NaCl; Separating the NaCl from the mixture; Obtaining a precipitant mixture of Leonite with KCl; Filtering said Leonite and washing with water to yield pure mixture of Leonite with KCl; Adding KCl to the Leonite with the KCl; and Decompose said Leonite with the KCl to SOP.

The present disclosure, in various embodiments, discloses hydrothermal methods, hydrothermally modified materials and dried hydrothermally modified materials. Certain dried hydrothermally modified materials can readily releases ionic species such as alkali metal ions (K.sup.+, Na.sup.+), silicate salts, and alkaline earth metal ions (Mg.sup.2+, Ca.sup.2+). Some dried hydrothermally modified materials can readily release aluminum ions and/or silicon, such as in the form of soluble silicates. Such processes and materials are useful, for example in economically preparing potassium releasing fertilizers.

The present disclosure, in various embodiments, discloses hydrothermal methods, hydrothermally modified materials and dried hydrothermally modified materials. Certain dried hydrothermally modified materials can readily releases ionic species such as alkali metal ions (K.sup.+, Na.sup.+), silicate salts, and alkaline earth metal ions (Mg.sup.2+, Ca.sup.2+). Some dried hydrothermally modified materials can readily release aluminum ions and/or silicon, such as in the form of soluble silicates. Such processes and materials are useful, for example in economically preparing potassium releasing fertilizers.

There is provided herein a process for the compaction of Polyhalite with a Potassium salt, wherein said process comprising: mixing a feed of polyhalite with a feed of said Potassium salt 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; screening said particles in a screener to yield fine 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 desired size fine particles which are transferred to a polish screener glazing, drying and oiling.

There is provided herein a process for the compaction of Polyhalite with a Potassium salt, wherein said process comprising: mixing a feed of polyhalite with a feed of said Potassium salt 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; screening said particles in a screener to yield fine 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 desired size fine particles which are transferred to a polish screener glazing, drying and oiling.

The disclosed invention describes a novel approach to the utilization of the fine mineral matter derived from coal and/or coal refuse (a by-product of coal refining) to convert a non-biodegradable plastic into a biodegradable plastic. The fine mineral matter could also be based on volcanic basalt, glacial rock dust deposits, iron potassium silicate and other sea shore mined deposits. The conversion of the non-biodegradable plastic into biodegradable plastic in soil further increases nutrients availability in soil with the transition metals released as a result of biodegradation of the biodegradable plastic.