The research article 'Regeneration assessments of filter fabrics of filter presses in the mining sector' has been published in the journal Minerals Engineering (Volume 168, 1 July 2021, 106922).
Abstract
In addition to investment costs, ongoing operating costs represent a major economic aspect of a process plant. From an entrepreneurial point of view, these should be as low as possible in order to generate maximum profit. In case of a filtration plant, costs also arise for personnel, energy, process media, and wear materials. While the former are sometimes difficult to influence, the latter item has a clear optimization potential. In filtration using a discontinuously operating apparatus, the filter media must be replaced after a certain number of cycles in order to be able to continue economical operation. Consequently, it is of great interest to maximize the number of cycles to reduce material purchases and downtimes. A typical application is the mining industry, where enormous process flows of tailings are dewatered using filter presses. These tailings mainly consist of particles in the lower micrometer range that deposit inside the filter cloth, which is referred to as blinding. Increasing blinding reduces the pore diameter and thus progressively increases the flow resistance of the fabric. As a result, the duration of the filtration cycles increases continuously and at a certain point the cloth has to be replaced to maintain economically viable operation. Besides potential occurrence of mechanical damage, blinding is the main reason for cloth changes. Since replacement is very expensive due to material costs and downtime, this paper investigates the possibilities of regeneration of industrially used cloths with different acids, bases, and ultrasonic bath cleaning procedures. Depending on the fiber types and the used solvent, almost complete cleaning is possible. Furthermore, tensile tests have been performed to confirm that these cleanings neither damage the cloth nor increase the risk of mechanical failure.
