Regulation Of Crystal Structure Of Fouling In Boiler And Evaluation Of Energy Saving And Environmental Effect

In many industrial heat transfer equipment, fouling was a common and consumptive problem, about ten billion dollars were consumed due to periodic cleaning and energy losses for fouling. Green anti-fouling technology had an extensive foreground of marketable application as energy saving and environmental protection became the two most important subjects of the world. The late-model copper-zinc alloy and mineral functional chinaware material were used to prepare an activated bed for water treatment of boiler in this work, the crystal microstructure can be controlled and the growth of hard fouling in boiler can be restrained too. The growth dynamic model of the fouling crystal was built to quest for the evaluation method of energy saving and environmental effect of the activated bed for water treatment of boiler.A simulated boiler system was set up, and the activated bed built up by mineral functional material and kinds of copper-zinc alloys for water treatment was put in the intake system respectively. The water parameters were tested such as rigidity, alkalinity, electric conductivity, pH, ORP and so on, then the interaction and transfer rules of Ca2+, Mg2+, Zn2+, CO32-, HCO3- of the activation-bed-boiler system were studied, and the steam quality was noted too. The effect on the fouling crystal modality was studied through SEM, EDS, XRD and particle size analysis. In simulated boiler system, the Zn2+ concentration increased when water flowed through copper-zinc alloy due to primary battery reaction. Zn2+ ions joined the growth process of fouling along with its concentration increasing. Some of Ca2+ ions on crystal surface were replaced by Zn2+, which affected the normal growth of calcium carbonate crystal. The structure of fouling changed so the purpose of growing soft fouling was achieved. Fe2+ ions in water system received electrons and became steady, so the growth of rust was restrained. Water was activated by mineral functional material, which enhanced its dissolving capacity, so the saturation of CaCO3 increased too.The energy saving effect of activated bed of simulated boiler system for water treatment can be evaluated by steam comparison measure, and its environmental effect can be evaluated by dosage of acid washing measure. The energy saving and enverionmental protect of boiler can be achieved through regulatling the crystal structure of fouling in the boiler. And the results of evaluation are consilient with the crystal microstructure and loose degree of fouling. The bigger the size of crystal and the lower the agglomerating force were, the better the performance of its evaluation of energy saving and environmental effect was.