Feasibility of Natural Zeolite for Heavy Metal Stabilization in Municipal Solid Waste Incineration Fly Ash: A Novel Approach

The current study investigated the sorption process of heavy metals, especially lead (Pb2+) and Zinc (Zn2+), in Municipal Solid Waste Incineration (MSWI) fly ash applying natural zeolite, namely mordenite, as an inexpensive adsorbent to assess its feasibility for the treatment of fly ash. Batch experiments were performed to investigate the effects of the influential parameters, such as metals initial ion concentration, dosage of adsorbent, liquid to solid (L/S) ratio, and equilibrium concentration of metal on the immobilization of Pb2+ and Zn2+, in a novel approach. Heavy metals removal efficiency increased with increasing the dosage of mordenite influenced by the media-specific surface area. Heavy metals adsorption is ascribed to various mechanisms of ion exchange and adsorption processes. The Langmuir and Freundlich isotherm models were investigated using the adsorption data. The adsorption process describes better in the Freundlich isotherm model compared to the Langmuir isotherm model with a high determination co-efficient (R2), especially for the adsorption of Pb2+. In addition, the affinity of mordenite to Pb2+ was shown to be higher than that of Zn2+. This allows the use of mordenite to capture of Pb2+ in MSWI fly ash. Results raise expectations about using mordenite as a low-cost material for treating MSWI fly ashes. The results show that heavy metal (Pb2+ and Zn2+) removed by mordenite adsorbent is practical and effective. In order to achieve the higher efficiency on heavy metal stabilization in MSWI fly ash, additional experiments are necessary.

Lessons learned from the Ezgeleh-Sarpol Zahab earthquake of November 2017:status of damage and disposal of disaster waste

A massive earthquake of magnitude Mw 7.3 shook Kermanshah Province in Western Iran along the Iraqi border on November 12,2017.The epicenter of the earthquake was approximately 10 km southwest of Ezgeleh Town in Kermanshah Province.Field observations almost 4 months after the disaster indicated that the earthquake had caused tremendous damage to most structures in both urban and rural areas,and left an enormous amount of disaster waste.To investigate the status of the dam-age and disposal of the disaster waste,remote sensing was conducted using an unmanned aerial vehicle(drone).Through the capture of low-altitude images by drone and the generation of 3D models,the quantity of debris accumulated in a waste disposal facility near Sarpol Zahab was estimated at approximately 480,000 m3.A compositional analysis of the disaster waste was performed using an imaging technique.This revealed that the disaster waste was largely composed of concrete(39.6%),hollow brick(35.4%),and gypsum(21.2%)in the urban area,whereas soil was the dominant component(77.4%)in the rural area.The damage caused to most buildings was essentially due to their non-standard construction.The manage-ment of debris from the damaged buildings was a critical issue for the authorities,and the lack of preparedness was a serious drawback that consumed an enormous amount of time,budget,and workforce.A practical post-disaster preparedness plan would help the decision-makers and the public to manage the otherwise overwhelming nature of the post-disaster conditions in a more reasonable manner.