สมบัติทางกายภาพและทางเคมีของโลหะหนักในมอร์ตาที่ใช้ซีเมนต์จากกระบวนการเผาร่วมกับตะกรันทองแดง

• Main Author: ศศิธร แก้วกันยา
• Other Authors: มนัสกร ราชากรกิจ
• Format: Theses and Dissertations
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 2006
• Subjects: โลหะหนัก; ปูนซีเมนต์; มอร์ตาร์; ปูนซีเมนต์ปอร์ตแลนด์
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:45074
• Institution: Chulalongkorn University

This research studied hydration of cement from co-incineration process in a full-scale cement kiln using a waste, copper slag, as an alternative raw material that was utilized up to 3.2% by weight of the raw mix. Analyses were done using X-ray Diffraction Spectrometer (XRD), Scanning Electron Microscope (SEM) combined with Energy Dispersive X-ray Spectrometer (EDS), and also by Fourier Transform Infrared Spectroscope (FT-IR). Sequential Extraction was applied to quantitatively examine partitioning of metals into fractions. Furthermore, Compressive strengths and leaching tests of cement mortars were evaluated. The sequential extraction results showed that approximately 20% of the heavy metals were distributed in Fraction 3 (bound to iron and manganese oxides). Majority of the heavy metals (80%) mostly partitioned into Fraction 5 (residual fraction) indicating that these stable or less leachable metals had entered such phase during cement production. In contrast, Ni and V were found in readily leachable forms, suggesting that the two metals are able to leach more easily to the environment than other metals. Consequently, the amounts of these metals in raw materials need to be controlled to protect the human health and the environment. Although the concentrations of heavy metals in the cement increased with the increasing amount of copper slag, there were no significance differences in intensities of major crystalline phases in the XRD patterns and FT-IR results of cement mortars at different replacement percentages. The compressive strengths results were satisfactory according to ASTM C109/C109M-05 and the leached metal concentrations did not exceed the limits set by the notification of Ministry of Industry (2005) and the US regulatory Toxicity Characteristic Leaching Procedure (TCLP). Finally, the results led to a conclusion that it is possible to substitute copper slag up to 3.2% by weight of the raw mix.