The results showed that both these measurement methods could be used as the analysis methods for the intermediate control of mixing dewatering process,and compared with dew point meter method,gravimetric method was better in accuracy,precision,harm to analysts and environmental protection.

This paper analyses measurement demands of velocity instrument method, spot location's choose, tachometer perpendiculars arrangement, how to eliminate system error for human-induced factor and advance degree of preciseness of measurement result and so on.