What is the harm for flotation machine agent overdoses?

In the flotation process, we often ignore the risk of reagent excessive.As the practice proving,there are many cases that the flotation index decline beacuse of the flotation reagents excessive, there are several aspects for flotation reagents excessive as follows:
1\the danger of the collecting agent.Firstly,destruct the selective of the flotation process.A large number of production practice and test proving,when the collector dosage exceed a certain range,then the concentrate grade would decline obviously.Even if the recovery rate is a little high,it can be more harm than good.Secondly,it will bring difficulty for the foam concentrate further selection and seperating the bulk concentrate if having excessive collecting agent.In this case,we often add more regulators to help a lot,for more regulators ,midding ore which containing excessive reagent will return to the procedure,mixing the flotation process,declining the flotation index,froming the vicious circle.Otherwise,Inhibitor dosage will increase following by the excssive collecting agent,which not only waste the reagents,but also increase content of the toxic drugs.Thirdly,the floatability of some mineral will decline because of the excessive collecting agent.For example,the excessive fatty acids collector will decline the floatability.This because collecting agent will form reverse layer of multilayer adsorption,polarity base towards outdoor,making the surface of the hydrophilic.Forthly,the excessive collector will form a large of bubble making difficult dewatering for concentrate and tailings,bringing difficult for thickeningand filtering.

2\the danger of  excessive inhibitor.when having excessive inhibitor,the mineral both wanting to flotate and being stopped will be stopped,making
 recovery rate decline.then,for improving the flotation ability of the flotation mineral,we should add more collector.
3\the danger of excessive activating agent.it not onlycan  damage the selective of flotation process,but also can have an effect with collector causing sediment,consuming large amounts of collector,for example,
4\the danger of excessive foaming agent,it can produce large of sticky and fine bubbles,make the gangue minerals easily adhere to the bubble,reduce the concentrate grade.If raw mineral has lots of slurry,it will from lots of sticky foam,cause dangerous accident.
The control of the reagent dosage plays an important role in improving the flotation process indicators,the excessive reagent dosage will damage the selective of the flotation process,increase the processing cost,and bring difficult for the flotation technology directly or indirectly.