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EFFECT OF SURFACE TEMPERATURE ON PARTICULATE AND CRYSTALLIZATION FOULING

The aim of the present experimental work is to study the influence of surface temperature on both particulate fouling (PF) and crystallization fouling (CF) of heat transfer surfaces. For this target, an experimental setup, with a Perspex transparent test tube of 200 cm length and 5.92 cm inner diameter has been designated and constructed. Water with a concentration of 1g/lit in case of PF and 42 g/lit in case of CF is used as a test fluid. The experimental runs have been carried out under different surface temperatures of 70, 88 and 103 o C (for PF) and 62, 84 and 106 o C (for CF). The experimental run is carried out for a long enough time to reach the asymptotic fouling resistance (in PF) and the maximum allowable working time of the heating coils (in CF). Obtained results show that the surface temperature has a great effect on the fouling resistance in both the fouling modes. In case of PF, both the fouling resistance and the asymptotic fouling resistance decrease with increasing the surface temperature, where in the case of CF, the fouling resistance increases in the same sense. The saw tooth effect is observed only in the PF fouling mode. In all the experimental tests, the delay time is very small and seems to approach zero. This may be due to high concentration of test fluids.