| 英文摘要 |
Our country has limited resources. With the improvement of policies and regulations on the disposal of related waste and environmental standards, the domestic high-temperature industries and heat treatment facilities produce a significant amount of inorganic waste such as dust and slag. There is an urgent need to further develop resource utilization technologies for these waste materials to reduce environmental costs. In the metal smelting industry, a substantial amount of waste is generated during metal refining, such as reducible slag from electric arc steel plants and aluminum dross from aluminum refining plants, with annual production quantities exceeding 400,000 tons and 10,000 tons, respectively. In the glass industry, the process of high-temperature melting for glass production generates large amounts of glass dust that is collected using baghouse dust collectors. Due to the presence of heavy metals, this waste needs to be disposed of in landfills. Regarding heat treatment facilities, municipal solid waste is predominantly treated through incineration, producing 200,000 tons of fly ash annually. Due to its high heavy metal content, it is classified as hazardous industrial waste and can only be solidified and buried, resulting in high disposal costs.
The main goal of this project is to develop resource utilization technologies for the waste produced from the aforementioned high-temperature processes. The aim is to effectively eliminate these wastes and reduce the environmental burden and costs associated with disposal and landfilling. This report highlights the following points：
1.For silicon-aluminum waste, sampling was conducted from the reducible slag of two steel plants five times and from aluminum dross six times. The analysis of TCLP, sulfides, and chlorides met regulatory standards. A preliminary inventory of aluminum dross and reducing slag was established, and after particle size classification and heat treatment, these materials were applied to the formula of alkali-activated cementitious materials. Under certain conditions, the optimal compressive strength of the test body can reach more than 400kgf/cm2, and the waste materials content can account for more than 30% of the cementitious material. The analysis of hydraulic concrete surface wear has been complete to evaluate its feasibility as a hydraulic structure application. 2.As for the incineration fly ash treatment, the quantity of the fly ash and the potential waste materials that are of thermal modification was conducted. The information regarding the annual production, treatment, and re-use of the potential waste materials including glass, aluminum dross, and steel slags were collected, and their basic characteristic was also analyzed. The information of the current thermal treatment technologies, marketing, and technology development of the incineration fly ash was collected as well. In technological issue, the energy saving composition design and the 12 tests of the sintering process were carried out and the 4 environmental standards, the density standard, and water content limit were achieved. 3. In terms of glass fly ash: Completed an inventory of recyclable resources from six major glass manufacturing factories in Taiwan, including the resources types, quantities, and market size in the glass fly ash. Completed 12 samples of various fly ash collections from architectural flat glass and tinted flat glass processes. Through characteristic analysis, establish 7 analysis and testing methods for glass fly ash, including purity, metal oxides (XRF), heavy metals (ICP), crystal water, particle size, NMR, and FT-IR spectroscopy. After collecting and discussing the purification technologies and scientific references related to glass fly ash and sodium sulfate production, we integrated, constructed, and tested different purification units such as dissolution filtration, chemical precipitation, centrifugation, crystallization, drying, and crushing. We completed the design and development of the wet chemical recovery process for glass fly ash and successfully tested the glass fly ash recovery process 12 times with 10 kg each time. The testing results showed that recyclable sodium sulfate products from fly ash had an average 98% purity and 74% yield. Through SGS inspection and analysis, it was verified that the composition and physical properties of the recyclable sodium sulfate products achieved target specifications. Finally, the recyclable sodium sulfate passed the glass raw material dissolution test and passed the reusing verification of the architectural flat glass process. The appearance and specifications of flat glass using recycled sodium sulfate comply with product requirements. Proves the feasibility of glass fly ash being recycled as a raw material in the glass manufacturing process.
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