engleski

Statistical Experimental Design Approach in Coal Briquetting

In the case when the number of independent variables is greather, a careful design for carrying out tests has to be made in order to obtain, with the smallest possible number of tests, as much as possible neutral information about the influence of independent variables on the dependent ones. Only on the basis of such design and its statistical analysis it is possible to come to right conclusions about the function of the whole system. The influence of pressure, temperature, humidity and granulation of the coal upon the resistance to pressure and the water absorption of the briquetts has been tested, with the aim to examine how each of the two dependent variables changes dependent variables and which of the mentioned independent variables significantly influences the dependents one. The full factorial design with 16 experiments and the central composite design with 27 experiments have been applied. The influence of the independent variables upon the dependent ones has been examined by applaying the analysis of variance. The influence values of individual factors and their interaction upon the dependent variables have been started as well as coefficients of curvilinear equation.

coal; experimental design; briquetting

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