Precipitation Characteristics of Crystallization Fouling on Metal Surface from 0.5mmol/l CaCO₃ Solution at 35°C

Abstract:

The comparative experiments on CaCO₃ crystallization fouling on brass, copper and stainless steel 304 and 316 at different pH at 35°C were carried out. The growing curves of fouling were got by direct weighing after static reaction experiments, and the morphology of crystals at different conditions was obtained by scanning electron microscope (SEM) and the parameters such as polymorphism, crystal size and so on were got, so the growing characteristics of CaCO3 crystallization fouling were known. The experimental results show the mass of crystallization fouling on stainless stee_{Subscript text}l surfaces are almost equal and increasing a little when pH increased, but the mass of fouling on brass and copper surfaces are close and far less than on stainless steel and increasing a lot when pH increased; not only the homogeneous nucleation rate in bulk solution and heterogeneous nucleation rate on metal surface are increased to generate more new crystal nuclear but also square aragonite and calcite are formed more by higher pH, so the mass of metal surfaces is more and the phenomenon is more obvious that single crystal has a size extremum by higher pH.

• Periodical: Advanced Materials Research (Volumes 614-615)
• Pages: 31-35
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.614-615.31
• Online since: December 2012
• Authors: Zhi Gang Zhou, Hua Zhang
• Keywords: CaCO₃, Coupon Test, Crystallization Fouling, Polymorphism

References

[1] Zhang Mingzhi, Wei Bo and Sun Gang. Temperature distribution and exergy transfer characteristics of the single-phase flow heat exchanger [J]. Journal of Power Engineering, 2009, 29(11):1023-1026

[2] Xu Zhiming, Wen Xiaoqiang and Zheng Jiaoli. Cooling water fouling resistance prediction of plate heat exchanger based on partial least-squares regression [J]. CIESC Journal, 2011, 62(6):1531-1536

[3] GB/T 7190.1.Glass fiber reinforced plastic cooling tower- Part 1: Middle and small glass fiber reinforced plastic cooling tower[S], (2008)

[4] GB/T 7190.2.Glass fiber reinforced plastic cooling tower- Part 1: Large glass fiber reinforced plastic cooling tower[S], (2008)

[5] GB/T 50392.Code for design of cooling tower for mechanical ventilation[S], (2006)

[6] GB/T 15452.Industrial circulating cooling water- Determination of calcium and magnesium- EDTA titration method[S], (2009)

[7] GB/T 19281.Analytic method for calcium carbonate[S], (2003)

[8] A. Herz, M. R. Malayeri, and H. Müller-Steinhagen. Fouling of roughened stainless steel surfaces during convective heat transfer to aqueous solutions [J]. Energy Conversion and Management, 2008, 49(11): 3381-3386

DOI: 10.1016/j.enconman.2007.09.034

[9] Yida. Liu, Yong Zou, and Liang. Zhao. Investigation of adhesion of CaCO3 crystalline fouling on stainless steel surfaces with different roughness [J]. International Communications in Heat and Mass Transfer, 2011, 38(6): 730-733

DOI: 10.1016/j.icheatmasstransfer.2011.04.003

[10] Threlfall. T. Structual and thermodynamic explanations of Ostwald's Rule [J]. Organic Process Research and development, 2003, 7(6):1017-1027

[11] Zhao Liang, Zou Yong, and Liu Yida. Effect of temperature on formation of crystalline fouling on heat exchanger surface [J]. CIESC Journal, 2009, 60(8):1938-1943

[12] Wang J., Shen Z.W., Shen Z.Q. Process dynamics and fractal analysis of new phase formation in thermal processes[J]. Journal of Thermal Science, 2001, 10(2):153-158

DOI: 10.1007/s11630-001-0058-x