Assessment of laboratory leach test methods for evaluation of environmental impacts by coal and gold mine waste
| dc.contributor.advisor | Deysel, Lore-Mari | |
| dc.contributor.advisor | Gomo, M. | |
| dc.contributor.author | Ramasala, R. J. | |
| dc.date.accessioned | 2019-07-09T12:30:00Z | |
| dc.date.available | 2019-07-09T12:30:00Z | |
| dc.date.issued | 2018 | |
| dc.description.abstract | Leach tests involves the extraction of the removable component from solids using a solvent. Leach tests are widely used to assess the potential impact of waste material on the environment. A variety of leach test methods exist and the selection of a leaching method depends on the type of leaching solvent and its chemical characteristics. While these methods have been in use for decades, there is limited research to compare the performance of the different leach test methods. Such information is particularly important when selecting method to use on the basis of the time efficiency and costs. This study therefore seeks to evaluate the performance of four conventional standard leach test methods: Toxicity Characteristic Leaching Procedure (TCLP) using acetic acid; Synthetic Precipitation Leaching Procedure (SPLP) using acid rainwater; Diluted Sulphuric Acid Base (DSAB) leach test method using dilutes sulphuric acid to mimic AMD and Water Leach – as for TCLP but replace with reagent water (deionised water). These leach test methods are assessed in a comparative way on solid mine wastes samples from coal and gold mines obtained from South Africa. The assessment of the four static leach test methods was conducted on the field samples, each sample with the same mineralogical composition in order to evaluate their performance. In order to assess the performance of these methods, the study compares the leached concentration results with the leachable concentration threshold from the NEM: WA No.59 of 2008 standard, furthermore it compares leached total dissolved salts (TDS) from the samples with the Water Quality Salinity Classification and Groundwater Quality Classification. The findings reveals that the leach test methods classify waste materials inconsistently. The leachate fromTCLP and DSAB methods falls under different waste Type classes. While leachates from SPLP and Water leach test methods falls in Type 3 class, which is known to be very low hazardous risk. In this way the Water leach test method, becomes more favorable because of less cost involved. The results further show that even though the sample leachate are classified as very low hazardous risk by the NEM: WA No. 59 of 2008, it can also pose salinity risk. In results, this shows that the leach test methods performs in different ways depending on the applied extraction fluids. | en_ZA |
| dc.description.sponsorship | Environmental Resource Management (ERM) | en_ZA |
| dc.description.sponsorship | National Research Fund (NRF) | en_ZA |
| dc.description.sponsorship | Institute for Groundwater Studies (IGS) | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11660/9990 | |
| dc.language.iso | en | en_ZA |
| dc.publisher | University of the Free State | en_ZA |
| dc.rights.holder | University of the Free State | en_ZA |
| dc.subject | Dissertation (M.Sc. (Institute for Groundwater Studies))--University of the Free State, 2018 | en_ZA |
| dc.subject | Geohydrology | en_ZA |
| dc.subject | Leach tests | en_ZA |
| dc.subject | Waste material | en_ZA |
| dc.subject | Environment | en_ZA |
| dc.subject | Toxicity Characteristic Leaching Procedure (TCLP) | en_ZA |
| dc.subject | Synthetic Precipitation Leaching Procedure (SPLP) | en_ZA |
| dc.subject | Diluted Sulphuric Acid Base (DSAB) | en_ZA |
| dc.subject | Water Leach | en_ZA |
| dc.title | Assessment of laboratory leach test methods for evaluation of environmental impacts by coal and gold mine waste | en_ZA |
| dc.type | Dissertation | en_ZA |