What is the difference between agricultural grade feed grade and industrial grade magnesium sulfate?

What is the difference between agricultural grade feed grade and industrial grade magnesium sulfate?

Summary

The main difference between agricultural grade, feed grade, industrial grade magnesium sulfate is that the content of the indicators is not the same, agricultural grade purity is low, feed grade magnesium sulfate purity is higher.

What is the difference between agricultural grade  feed grade and industrial grade magnesium sulfate?
What is the difference between agricultural grade feed grade and industrial grade magnesium sulfate?
        The main difference between agricultural grade, feed grade, industrial grade magnesium sulfate is that the content of the indicators is not the same, agricultural grade purity is low, feed grade magnesium sulfate purity is higher. 
Agricultural grade magnesium sulfate
Agricultural grade magnesium sulfate

1:Industrial grade magnesium sulfate:

Generally use powder; very strict requirements on the content of iron and manganese and other metal impurities.

Used for the extraction of zinc in polymetallic minerals; used directly as a sewage treatment agent or as a raw material for sewage treatment agent; used as a dyeing agent and reductase in chemical fiber and textile industry; other industrial uses

2: Feed grade magnesium sulfate:

Used as a feed additive, or trace element additive.

Generally used in powder or small granules; the requirements for heavy metals such as lead, arsenic and cadmium content are very strict, as these contents exceeding the standard will lead to animal poisoning and indirectly affect human health.

3: Agricultural grade magnesium sulfate:

Generally used as fertilizer additives, using more particles.

The application of magnesium sulfate in agriculture makes the soil contain a certain amount of magnesium to ensure that the plant growth of the required trace elements (foliar spraying with the exception of external fertilizer).There are certain requirements on the content of magnesium and heavy metals and water insoluble content.