Recycling of harbor sediment as lightweight aggregate

• Published in: Marine pollution bulletin Vol. 57; no. 6; pp. 867 - 872
• Main Authors: Wei, Yu-Ling, Yang, Jing-Chiang, Lin, Yong-Yang, Chuang, Shih-Yu, Wang, H. Paul
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Kidlington Elsevier Ltd 2008; Elsevier
• Subjects: Aggregates and other concrete constituents; Applied sciences; Bloating process; Buildings. Public works; Cement concrete constituents; Conservation of Natural Resources; Construction Materials; Exact sciences and technology; Fe K-edge XANES; Freshwater; Geologic Sediments - chemistry; Hot Temperature; Lightweight aggregate; Materials; Natural aggregates; Other wastes and particular components of wastes; Particle Size; Pollution; Sediment recycling; Sintering; Wastes; Water - chemistry; Water Pollutants, Chemical - analysis; Asia; Taiwan; ISEW, Taiwan; Lightweight aggregate; Sediment recycling; Bloating process; Sintering; Fe K-edge XANES; Heat treatment; XANES spectrometry; Harbor; Crushing; Construction materials; Dredging; Iron; Sediments; Coastal zone; Manufacturing process; Upgrading; Risk assessment; Waste reuse; Speciation; Drying
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2008.03.033

Sediment sampled from Taichung Harbor was mixed with local reservoir sediment at different weight ratios to prepare lightweight aggregate at 1050, 1100, and 1150 °C. A pressure of 3000 or 5000 psi was used to shape the powder mixtures into pellets before the heating processes. The results indicate that the leaching levels of trace metals from the lightweight aggregate samples are considerably reduced to levels less than Taiwan Environmental Protection Administration regulatory limits. Increasing final process temperature tends to reduce the bulk density and crushing intensity of lightweight aggregate with a concomitant increase in water sorption capability. Lightweight aggregate with the lowest bulk density, 0.49 g cm −3 for the 5000 psi sample, was obtained with the heating process to 1150 °C. Based on the X-ray absorption near edge structure results, FeSO 4 decomposition with a concomitant release of SO x ( x = 2, 3) is suggested to play an important role for the bloating process in present study.