Efficacy and Applications of Microbial Induced Calcium Carbonate Precipitation in Coal Ash Management

William Odle, Newfields
Brina Montoya, North Carolina State University
Pegah Ghasemi, North Carolina State University

Description

Efficacy and Applications of Microbial Induced Calcium Carbonate Precipitation in Coal Ash Management Authors Mr. William Odle - United States - Newfields Prof. Brina Montoya - United States - North Carolina State University Dr. Pegah Ghasemi - United States - North Carolina State University Abstract Coal ash impoundments have risks related to structural stability, liquification, and trace metals leaching to groundwater or surface water sources. Microbial induced calcium carbonate precipitation (MICP) offers a potential approach for managing these risks. In this study, a protocol for MICP treatment of coal ash has been experimentally developed. The MICP treatment was applied to three separate coal ash samples from different power plants, and the efficacy of the MICP treatment evaluated utilizing shear wave velocity, electrical conductivity, pH measurement, acid washing, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Two of the coal ash samples were successfully treated with MICP, and the third sample was not effective which could be related to insufficient carbon content. Carbon content and other possible factors affecting the MICP treatment of coal ash are identified and discussed in terms of efficacy and inhibition of the stabilization process. Considering these factors, opportunities for MICP applications in coal ash management and stabilization of at-risk areas are assessed for enhancing stability, mitigating liquification risk, and reducing leaching potential of trace metals.

 
May 14th, 2:00 PM May 14th, 2:30 PM

Efficacy and Applications of Microbial Induced Calcium Carbonate Precipitation in Coal Ash Management

Grand Rapids, Michigan

Efficacy and Applications of Microbial Induced Calcium Carbonate Precipitation in Coal Ash Management Authors Mr. William Odle - United States - Newfields Prof. Brina Montoya - United States - North Carolina State University Dr. Pegah Ghasemi - United States - North Carolina State University Abstract Coal ash impoundments have risks related to structural stability, liquification, and trace metals leaching to groundwater or surface water sources. Microbial induced calcium carbonate precipitation (MICP) offers a potential approach for managing these risks. In this study, a protocol for MICP treatment of coal ash has been experimentally developed. The MICP treatment was applied to three separate coal ash samples from different power plants, and the efficacy of the MICP treatment evaluated utilizing shear wave velocity, electrical conductivity, pH measurement, acid washing, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Two of the coal ash samples were successfully treated with MICP, and the third sample was not effective which could be related to insufficient carbon content. Carbon content and other possible factors affecting the MICP treatment of coal ash are identified and discussed in terms of efficacy and inhibition of the stabilization process. Considering these factors, opportunities for MICP applications in coal ash management and stabilization of at-risk areas are assessed for enhancing stability, mitigating liquification risk, and reducing leaching potential of trace metals.