The Research On Detection Of Pulp Fiber's Suface Charge

With the development of the paper industry , many paper chemicals are applied one after the other. It causes the charges of paper furnish varied much complicatedly in the wet-end. While the charge analysis is a powerful tool to optimize and stabilize the wet-end chemistry.Colloidal titration and zeta potential measurement are two diffirent methods that are often utilized in monitoring paper machine wet-end operation.This paper mainly focuses on the principles,characteristics, measurement procedure, research progress , method comparision of colloidal titration and zeta potential measurement and the signification of charge analysis. It is suggested that if possible, both approaches should be used together in routine evaluation in order to optimize paper machine wet-end operation.This paper focus on the source and nature of electrostatic charge on papermaking materials, the wet and chemistry performance of fiber and fines and all the chemical and colloidal surface reaction between fiber and fines. The structure and chemical constitution, and the influence of beating degree and pH value on their electrokinetic characteristics were discussed in detail. This paper also focus on the principle and method of charge analysis of paper-machine wet-end using colloid tit ration technique.Zeta potential is an important parameter in wet-end electrical charge characterization. It is essential to wet end control and optimization. In this paper , a method for factors leading to Zeta potential variation are being discussed. These include fibre species and its pulping methods , fines content in the stock furnish , pH , stock freeness , inorganics , and others. This paper describes in detail the definition of Zeta potential, the potential on-line measurement and the research development of Zeta potential on-line measurement.The effects of Zeta potential on microparticle systems are discussed.Conductivity is an important chemical quantum. In the method of electrod conductivity measurement, the measure electrode behave as a complicated electrochemistry system during measurement The factors that infect the precise measurement of conductivity is polarization effect,capacitance effect and temperature . In this paper a four-electrode half bridge device which measures electrical properties of fermentation broth is described. This system ,because no current passes through the measuring electrodes ,virtually eliminates the interferences of elect rode polarization. The system can be applied in liquor of paper pulp.After the precise measurement liquor conductivity under certain temperature, the temperature compensation of conductivity is studied in this paper.