Research On Automatical Determination And Application Of Microscopic Coal Etrography Parameters

With the continuous updating of the technologys such as the computer control and photovoltaic conversion in recent years, coal petrography has got rapid development and wide application, the role of which in the field of coal blending for coking is irreplaceable. The research of automatic determination of coal petrography parameters and their application has become more meaningful. Based on microscope automatic focus method according to the sample plane equation, improving the focusing efficiency of microscope by the measures such as rectifying the errors caused by step motors determining coordinate distance, the whole focusing time has been controlled within2minutes and the total measurement time about10min,15min and25min, scanning10000points,20000points and10000points respectively.With sample preparation according to the national standard, using HD full automatic microscope photometer to respectively manually and automatically determine the vitrinite reflectance and its standard deviation of18kinds of single coal and14kinds of mixed coal samples, and fitting the determination results, the correlation between manual determination results and10,000points automatic determination results of single coal vitrinite reflectance has been obtained: ymanu=0.050+0.982xauto, and its correlation coefficient is0.986; Its standard deviation correlation is:ymanu=0.033+0.791xauto, and correlation coefficient0.815. The correlation between10,000points and40,000points automatic determination results of vitrinite reflectance is:y4w=0.0115+0.8966x1w, and its correlation coefficient is0.982; Its standard deviation correlation is:y4w=-0.0013+1.2346x1w., and correlation coefficient0.822. The correlation between manual determination results and40,000points automatic determination results of mixed coal vitrinite reflectance is: ymanu=-0.0653+1.167xauto, and its correlation coefficient is0.936; Its standard deviation correlation is:ymanu=0.0395+0.8325xauto,and correlation coefficient0.972. All the fitting results have passed significance testing with the confidence coefficient99%.Using the existing software functions of HD full automatic microscope photometer system such as "curve stripping peak", a new method of automatic determinating coal vitrinite content has been put forward. Comparing manual determination results with automatic determination results of seven kinds of single coal, with their relative errors within0.01, the minimum only0.008, the maximum0.096, this method can be applied to automatical determination of the mixed coal vitrinite content.The rule of apparent caking index G’ value, determinated by adding different proportion inert content to14kinds of single coal, changing with vitrinite content has been investigated. Research shows that G’ value and vitrinite content have significant linear relationship. Employing the reciprocal of the slope of linear fitting equation as the index to investigate vitrinite active quality can eliminate the interference of vitrinite content difference of every single coals. That the Gaussian curve model is the optimization model to describe coal vitrinite activity quality of different metamorphic degree has been demonstrated. On this basis coal vitrinite relatively active quality of different metamorphic degree has been provided, which lays a foundation to investigate the influence of coking blending caused by vitrinite quality differences.