Research On Technology Of Autoclaved Brick Produced By Semi-dry Calcium-based FGD By-products

Along with our country to control and reduce SO2 emission intensity increasing, Power plant boiler flue gas desulfurization has entered a stage of rapid development, But then produces a large amount of desulphurization waste disposal problems. Especially half dry desulfurization process of desulfurization ash which Difficult to achieve comprehensive utilization, Because of its physical and chemical properties. Because of the lack of advanced half dry desulfurization ash comprehensive utilization technology, At present the desulfurization ash to pile up and abandoned treatment which caused a certain degree of pollution to the environment and to the enterprise has formed a larger pressure. Therefore, how to realize the half dry desulfurization ash comprehensive utilization has become an urgent major issues of national and enterprise. In this paper, System analysis and research the preparation principle of autoclaved brick, and studies the forming mechanism of strength of autoclaved brick that use a half dry desulfurization ash autoclaved brick as the main raw material preparation,Studied with half dry desulfurization ash autoclaved brick as the main raw material preparation principle and process, and industrial experiment was carried out. On the basis of a series of single factor variables, to explore the influence of different proportion on properties of autoclaved brick, eventually determine the optimal formula of the desulfurization ash autoclaved brick than range. For production MU20 strength grade desulfurization ash autoclaved brick, of the desulfurization ash content can be controlled at about 50%, lime dosage control at 10%; For production level-mu15 strength grade desulfurization ash autoclaved brick, of the desulfurization ash content can be controlled at about 60%, lime dosage control at around 8%.Using scanning electron microscopy(SEM), X-ray energy spectrum(EDS) and X-ray diffraction(XRD) these three instruments dry-process desulfurization ash autoclaved brick is analyzed, and combined with chemical analysis method. Then studies the forming mechanism of half the strength of the dry process autoclaved brick. The studies have shown that the strength of the desulfurization ash autoclaved brick comes mainly from the following aspects: first, quick lime hydration reaction to produce gel; Secondly, quick lime hydration of Ca(OH) 2 and of the desulfurization ash gel that inspired the activity of fly ash, gypsum etc; Third, react with aluminate generating hydrated calcium sulphoaluminate; Fourth, the contribution of slag on the strength.