The so-called non-cyanide flotation is not multi-metal cyanide as inhibitors when sulphide ore flotation separation. As described above, the cyanide (sodium cyanide and potassium cyanide) are highly toxic agents, as sphalerite and pyrite inhibitor, resulting in water containing cyanide tailings, caused severe environmental pollution. It is common to purify tailings water and wastewater, such as adding bleach. Economically, cyanide is more expensive. In addition, cyanide dissolves precious metals such as gold and silver . Therefore, when cyanide is used for ore containing precious metals such as gold and silver, it is not suitable for comprehensive recovery. Therefore, it is generally emphasized at home and abroad that little or no cyanide is used. At present, in the domestic flotation of polymetallic sulphide ore, in order to find cyanide substitutes, to achieve cyanide-free flotation process, or to minimize the amount of cyanide, a lot of experimental research work has been done, and some achievements have been made. The plant has achieved a cyanide-free flotation process. Most of the experimental studies used sulfite (H 2 SO 3 ), sulfur dioxide (SO 2 ), sodium sulfite, and sodium thiosulfate instead of cyanide to inhibit sphalerite and iron sulfide. Such agents little toxicity, no dissolution of gold, silver and other precious metals, but they are easily suppressed through activation of sphalerite, weak inhibition of the copper minerals, and even activation, copper-zinc facilitate separation. The main disadvantage is that the inhibition is easy to disappear without the strong cyanide agent, and its use is most difficult to control. In addition, the following methods can be substituted for cyanide. 1, ZnSO 4 + Na2CO 3 (or sodium sulfide) inhibits sphalerite, pyrite, commonly used in lead -zinc separation, zinc-suppressed lead. 2, P 2 S 5 + NaOH (also known as Knox method NoKes), under the conditions of pH = 8 ~ 11, for the separation of molybdenum and sulfide ore flotation, inhibition of copper, lead, zinc, iron sulfide. 3. Potassium manganate (K 2 MnO 4 ) and potassium permanganate (KMnO 4 ) can selectively inhibit pyrite at pH=7.5-9. Domestically, factories and mines that have achieved good results using cyanide-free flotation are listed in the table below. Domestically used factories with non-cyanide flotation to achieve better results Serial number Factory name Ore type Process method index 1 Fankou Lead-zinc mine vulcanization Lead-zinc mine Na 2 CO 3 + ZnSO 4 replaces cyanide, zinc-suppressed lead Similar to the separation index of Pb-Zn obtained using cyanide (about 100 g/ton) 2 Toon Lead-zinc mine Copper, lead and zinc Sulfide ore Na 2 S 2 O 3 +FeSO 4 in lead-free copper in acidic medium Better than the index of cyanidation 3 Bayi Copper mine Copper zinc Sulfide ore Na 2 SO 3 +Na 2 S instead of cyanide zinc-suppressing copper Copper and zinc separation index is better than cyanide flotation 4 Yinshan Lead-zinc mine vulcanization Lead-zinc mine Using the "equal floatable" process, completely without cyanide, using zinc and zinc sulphate Similar to the indicator of adding cyanide 5 Peng County Copper mine Copper zinc Sulfide ore Reform the production process, that is, direct direct flotation to coarse concentrate re-grinding priority flotation, mixed flotation zinc and sulfur separation process, reduce the amount of collector when copper is selected, without cyanide, copper and zinc sulfur Separation The new process increases the copper concentrate grade by 1%; the recovery rate by 1.5%; the zinc recovery by 1%; and the sulfur recovery by 2%. It can be seen that the cyanogen-free flotation is also a good sorting indicator. There are still many examples in this aspect, which are not introduced here. Roots Blower For Chemical Plant Ring Blower,Roots Type Blower,Rotary Lobe Blower,Three Lobe Roots Blower Shandong Heli Machinery Co.,Ltd , https://www.chinaheliblower.com