一种谐振式密度（浓度）分析仪的研制与应用

矿浆浓度（密度）的测量一直是选矿行业的技术难题，对矿浆浓度（密度）的测量精度直接影响着选矿自动化的控制水平和控制效果。谐振式密度（浓度）分析仪是根据元器件振动衰减原理而设计，主要由音叉传感器、驱动检测电路、主控芯片、辅助电路和相应的壳体构成。浓度仪在工作时由激励线圈产生激励促使音叉体产生振动，振动频率由压电晶体检测出来，并通过移相和放大电路后转换为测量所需的电信号。当液体流经振动叉体时，因流体质量的改变引起谐振频率的变化，仪器采集系统采集这些频率变化。由于不同密度的流体流经振动系统时会产生不同的振动频率，仪器检测出振动频率变化后即可通过振动频率与密度间的函数关系式计算出流经流体的密度值，推算流经流体的浓度值。谐振式密度（浓度）分析仪在南京某选厂应用结果表明，该设备可以提高选矿过程浓度检测的准确性和可靠性。

Development and Application of a New Type of Resonant Density (concentration) Analyzer

Measuring pulp density ( concentration) ,has been a technical problem in mining industry,pulp density ( con-centration) measurement accuracy directly affects the level of control and the effect of the mineral processing automation con-trol. Design of a new type resonant density ( concentration) analyzer is based on the principles of the vibration damping compo-nents. The instrument is mainly driven by tuning fork sensor,detection circuit,main control chip,auxiliary circuit,and the cor-responding shell. Excitation coil makes the tuning fork vibrate when concentration meter works,the vibration frequency detected by piezoelectric crystal. It is converted to the electrical signals of the measure needs after through the moving phase and amplif-ying circuit. When fluid flows through the body vibration fork,the change of the resonance frequency caused by the change of fluid quality,instrument collection system collected the frequency shifts. Due to the different density of fluid flowing through the vibration system will produce different vibration frequency,using the function relation between the vibration frequency and the density calculate the density value of the flowing fluid after the instrument detected the vibration frequency shifts. Finally,the density value of the flowing fluid will be calculated. Application of resonant density ( concentration) analyzer in a plant in Nan-jing indicated that,the device can improve the Accuracy and reliability in density measurement of mineral processing.