Summary: | 碩士 === 國立高雄應用科技大學 === 化學工程與材料工程系 === 99 === For the treatment of aluminum dross, we can make it by ways of thermal stabilization, alkali dissolution, and so on. In this study, hydrochloric acid or sulfuric acid are added into the ammonia for forming ammonium chloride or ammonium sulfate colloid. Due to the composition of clay (Al2O3.SiO2) in aluminum dross with 80% of particle size being below 310 μm, it’s easy to shaping. In addition, because aluminum dross is composed of alkalis and silica, it’s easy to be hydrolyzed into gel type of C-S -H and gel type of CA with a sticky and a binding force. For the corrosion by acid on the surface of fine particles, it will increase the surface area of contact. As a result, we shall carefully choose the concentration of acid and water content. It is crucial for the process of drying after they are shaped. Therefore, by continually testing, 37% hydrochloric acid/water weight ratio = 1/2 and 98% sulfuric acid/water weight ratio = 1/5 are the most suitable ratio for the stabilization process. For finished product, either in a dry or a follow-up water immersion test, they all are stable structure. On the other hand, if adding the products to the concrete and replacing the sand, the granulated substance with a body pressure test are in the range of 165~170 kgf/cm2. If they are stored by the granulation, their chemical properties are also stable. Even if with water, ammonia will not be released. If the products are dried by granulation and immersed by water, the stable specimens will have a great number of economical advantages on aggregate use, such as the replacement of earth fill materials, landscaping brick, and the raw materials of trail brick. Aluminum dross by weight ratio 10%, 15%, 20%, 25%, 30% are used to replace partly clay for the brick firing. The intensity of products via a body pressure test is in the range of 83.0~151.9 kgf/cm2. If aluminum dross is calcined directly at 1100 ℃ and removed the flammable compounds, the products with a body pressure test of 189 kgf/cm2 can be used as additives by adding it in the Pu Shu Lan concrete materials.
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