Scaling is a form of fouling commonly found in heat exchangers, steam generators, and cooling systems. It occurs when dissolved chemical species interact and precipitate as inorganic salts. How Phosphate Hideout Develops Calcium- and sodium-based compounds are among the most common scale-forming species. Their solubility depends on temperature and pH and can change significantly as
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Cooling towers reject heat through the partial evaporation of circulating water. This evaporation rapidly concentrates the chemical species naturally dissolved in the water. Scale Formation The principal scale found in cooling towers is calcium carbonate, which forms from the decomposition of calcium bicarbonate. Other deposits may contain magnesium-, sodium-, or silica-bearing compounds. Their solubility depends
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Failures during commissioning activities such as chemical cleaning or steam blowing may remain hidden for the first months of operation, yet they can have a direct and lasting impact on power-plant performance. This case examines damage to the regeneration system of a concentrated solar power (CSP) plant and explains how it reduced plant productivity. Solar
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A sudden change in a flow passage—typically an increase in cross-sectional area—can cause water pressure to fall rapidly below the saturation pressure at its temperature, producing instantaneous vaporization. Expansion and Flashing Because the process is approximately adiabatic, there is no external heat exchange and total enthalpy remains essentially constant. Part of the liquid flashes into
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A computational fluid dynamics (CFD) simulation was performed to study the effect of flue-gas velocity through the final-stage modules of a heat recovery steam generator (HRSG) preheater. Purpose The simulation produced a temperature map of the preheater module, making it easier to understand how energy is distributed across the tube bank. It also provided information
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Ineffective Chemical Cleaning? Introduction Ineffective chemical cleaning? Not really… we have encountered situations where engineers and operators complaint about the cleanliness of the boiler as they see a black liquid coming off the blowdown system during first fire. It´s not difficult to get carried away by a first impression and put into question the effectiveness
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