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In the power, petroleum, chemical industries and other fields, the fouling problem has been the most difficult one which needs to be solved urgently. Teflon coating belongs to low surface energy fluorocarbon material, which has superior performance in the field of anti-fouling. The effects of the surface characteristics of Teflon coating on CaCO3 fouling were studied in this paper. The result confirmed a great relationship between the coating surface characteristics and the fouling formation.The surface roughness, contact angle, surface energy of solid materials and interfacial energy between solid material and liquid were measured and calculated, and then the evolution curves of fouling were obtained by way of direct weighing. The fouling processes of the Teflon coating surface were investigated by contrastive experimental research method in the condition of different concentration (C = 800mg / L, 1000mg / L, 1200mg / L), different velocity (v = 0.1m / s, 0.15m / s, 0.2m / s) and different temperatures (t = 30℃, 40℃, 50℃) . In addition, the experimental data has been processed and error analysed.The experimental study showed that: with increasing concentration of the liquid, the amount of unit area fouling on the coating surface is increased; when the temperature of the liquid goes up, the amount of fouling is increased, too; meanwhile, when we reduce the flow velocity, both the amount and the velocity of fouling formation are increased; the coating surface contact angle, interfacial energy between solid material and liquid, and the surface roughness have no clear law for the formation of CaCO3 fouling. There is an important impact of the material’s surface energy upon fouling formation: the smaller the surface energy, the better anti-fouling properties of solid materials. In addition, the Teflon coating surface was scanned and the result shows that the micro-structure is different. Observe PFA (perfluoroalkoxy copolymer) coating surface by scanning electron microscope, in the high magnification, the surface is still very smooth. The final study indicated that the anti-fouling properties of the Teflon coating were better than those of high surface energy materials obviously, and PFA is the best anti-fouling materials among several Teflon materials.
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