Experimental Study on CaCO₃Fouling Characteristics during Falling Film Evaporation

authored by

Zhikou Ding, Wei Li, Lei Wang, Limin Zhao, S. A. Sherif, Rui Wang, Stephan Kabelac

Abstract

Falling film evaporation is widely used in solar desalination systems. Fouling is an important problem to be addressed in many applications involving heat transfer including processes involving the utilization of solar energy in desalination applications. In the research upon which this paper partly reports, an experimental investigation was carried out on a vertical tube in falling film evaporation to determine the effects of temperature, velocity, the use of a porous-sintered tube, and the use of Teflon coating on calcium carbonate deposition characteristics. During the fouling experiments, the pressure inside the test tubes was maintained constant at 101.3 kPa, and the inlet temperature was maintained at 373 K, while allowing the water mass velocity to vary from 0.42 to 1.05 kg m-1 s-1. Results show that the fouling in the test tube becomes more serious as the temperature increases and the flowrate decreases. Compared with stainless-steel tubes, porous-sintered tubes can significantly reduce fouling resistance, but at the same time they bring about a decrease in the heat transfer coefficient. The Teflon coating also has anti-fouling performance but does not affect the heat transfer coefficient in stainless-steel tubes. Through the weighing of local fouling deposits, it has been found that the mass of the fouling deposits in the lower part of the tested tubes is greater than that in the upper part.

Organisation(s)

Institute of Thermodynamics

External Organisation(s)

Zhejiang University (ZJU)
SINOPEC
University of Florida (UF)

Type

Article

Journal

Journal of Solar Energy Engineering, Transactions of the ASME

Volume

144

ISSN

0199-6231

Publication date

04.2022

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Renewable Energy, Sustainability and the Environment, Energy Engineering and Power Technology

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1115/1.4052937 (Access: Closed)