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• SS316L test segment surface was effectively coated with zirconium. • Physical vapor deposition technique was used to develop thin layer on SS316L surface. • Fouling resistance and heat transfer coefficient were evaluated for coated surface. • Coated surface reduced the fouling resistance and deposition rate. • Coated surface increased the heat transfer coefficient. Fouling is a major problem in many industrial heat exchangers as in these devices water has been used for heat exchanging purposes. With the commencement of foulants deposition on heat exchanger surface the performance of heat exchangers is deteriorated due to lower thermal conductivity of the deposits formed on the heat exchanger surface. This study investigated the heat transfer and mitigation of CaCO 3 fouling by applying zirconium coating layer on heat exchanger surface. Zirconium was chosen as a coating material because of its surface adhesion and one of the best corrosion resistance materials. The Physical Vapor Deposition approach was implemented to develop a coating layer on heat exchanger surface. Heat transfer was investigated at numerous temperatures and flow rates to examine the impact of coating on heat transfer. Fouling experiments were conducted to examine the CaCO 3 accumulation on the uncoated SS316L and Zirconium coated surfaces. After the fouling experiments, the coupon was disassembled from the test segment for the investigation of surface texture, after fouling effect and the morphology of deposits was assessed by using Field Emission Scanning Electron Microscopy (FESEM). Results reveal that the Zirconium coated surface declined the fouling deposition and improved the heat transfer. [Display omitted] [ABSTRACT FROM AUTHOR]

• Graphene nano platelets (GNP) were covalently functionalized with clove. • Thermo-physical properties of clove treated GNP were analyzed. • Test specimen with & without clove treated additives was investigated in test rig. • Fouling resistance and heat transfer coefficient (h) performance were evaluated. • Clove treated GNP enhanced the heat transfer and reduced the fouling deposition. Calcium carbonate (CaCO 3) is one of the main fouling elements of the crystallization fouling that causes critical problems in the operation of industrial heat exchangers. This study presents the retardation of CaCO 3 Fouling, and heat transfer enhancement of a tube heat exchanger immersed in a CaCO 3 rich solution containing clove treated graphene nano platelets (C-GNP) additives as suspension. Thermo-physical properties of water-based C-GNP additives nanofluid were tested before running the experiment. Experimental investigation was conducted to assess the C-GNP additives performance in the enhancement of heat transfer and reduction of fouling deposition. For the retardation of fouling experiments, the hard water or super saturated fouling solution of 300 ± 20 mgL−1 was prepared. To maintain the hard water concentration until the end of the experiments, a complexometric titration was adopted to monitor the CaCO 3 concentration at every 6 h. interval. The FESEM was utilized for the investigation of the morphology of CaCO 3 deposition on the heat exchanger surface. The results of this study demonstrate that the addition of C-GNP enhanced the heat transfer and reduced the foulant deposition without any effect of corrosion. The results also revealed the inverse relationship between the additive concentration and the fouling resistance. The outcomes of this study also support the achievement of United Nation sustainable development goal (SDG) target 7.3. [Display omitted] [ABSTRACT FROM AUTHOR]