The technology developed at the University of Illinois at Urbana-Champaign reduces carryover impurities in froth, improving the cleaning properties of flotation devices and offering the potential for higher throughput in both new and existing cleaning plants.

During coal processing the product improves the separation of fine coal particles from impurities, resulting in a purer product, the University said.

It greatly increases a froth flotation system’s productivity and efficiency, reducing the resources, including the operating/maintenance costs, required to purify a given quantity of coal.

The froth washer attachment can be used in any processing/extracting application where froth flotation can be used, requiring only minor changes in surfactants, frothers and flow characteristics.

University scientist Latif Khan said by eliminating the need for repeated step-wise cleaning a processing facility can greatly improve its productivity, reduce its costs, and produce a purer product with fewer flotation cells and/or processing runs.

Khan estimated mineral processors could save one-third to one-half on capital equipment and operating costs. Overall processing efficiency would also increase.

The technology can be installed as a simple and inexpensive add-on to existing flotation devices or integrated into the design of new flotation devices.

Laboratory testing has shown that under optimum conditions a flotation device equipped with this attachment surpassed the best performance of any flotation device, as predicted by the advanced flotation release analysis (AFRA) standards. Products processed by the University’s technology had 60 percent less ash content, 33 percent less sulfur content, and twice the combustible recovery than AFRA standards predicted.

Companies can license this froth washer technology, which is wholly owned by the University of Illinois, for use in coal processing or other processes that require separating fine materials or other particles.

The technology will soon begin a full-scale demonstration at a coal cleaning plant in Illinois. Five existing subaeration cells will be fitted with the device and compared with the performance of the conventional flotation circuit at the plant.