Ferrous sulphate can be used for water treatment caused by non-metal or heavy-metal element pollution such as municipal wastewater, industry wastewater and underground water. In addition, ferrous sulphate also functions well in odor control applications by preventing the formation of hydrogen sulfide. On the agriculture field, ferrous sulphate can be used as micro fertilizer to prevent crops from Fe deficiency, effectively improve soil, move moss and lichen. Meantime, it is the catalyst making plant green and plant absorption. On the Industrial field, ferrous sulphate can be used to make pigment such as Ferric Oxide series products, or used as a mordant in dyeing wool, in the manufacture of ink. Ferrous sulphate also can be used as feed additive to cure animals' ferrous deficiency, and stimulate the growth of animal's body.