Mining operations affects the quality of natural water streams through a number of ways including use of water in processing ore. The quality of the water from processing plants could have an adverse effect on aquatic life, on the deterioration of concrete and metal structures, and result in increased costs of water treatment. These environmental effects may be problematic considering the shortage of water supply around coal mines. To limit the environmental impact and reduce their freshwater usage, coal preparation plants have developed water usage strategies. The most common strategy is to recycle and reuse water. Recycled water, however, generally contains a large quantity of dissolved inorganic electrolytes, which may affect froth flotation. In this paper, we studied the variation of water chemistry in a coal preparation plant in the Hunter Valley in NSW, Australia and the consequences of these changes on the performance of flotation. The quality (ie conductivity, pH) of the process water measured for the equivalent of two years over a three-year period and daily average data was subjected to a vigorous statistical analysis. The statistical analysis was performed using the open source software R run in RStudio v1.1.383 (RStudio, Inc.). Apart from the water quality data, attempt was also made to analyse daily rainfall and maximum temperature data recovered from the Australian Bureau of Meteorology in order to assess the impact of seasonal changes on water chemical composition. The results showed large fluctuations in water compositions mainly due to the seasonal variations and changes in the water management strategies. The maximum daily temperature was found be an important factor controlling the amount of inorganic electrolytes and consequently conductivity in the water. The effect of the quantity of ions in the water on the flotation process was also studied. The concentration of salt was found to strongly affect the gas dispersive properties in the flotation cell and the cell performance. Overall, the results urged a need for water quality monitoring and control in minerals and coal processing plants. *This is an abstract only. No full paper was prepared for this abstract.*
CITATION: Bournival, G, Lambert, N and Ata, S, 2019. The importance of water quality monitoring in mineral processing plants, in Proceedings Future Mining 2019, p 160 (The Australasian Institute of Mining and Metallurgy: Melbourne).