this paper summarises test results that were used to validate a model and scale-up procedure of the high pressure grinding roll hpgr which was developed at the jkmrc by morrell et al. morrell, lim, tondo, david,1996. modelling the high pressure grinding rolls. in: mining technology conference, pp. 169-176. . verification of the model is based on results from four data sets that describe the
and mining sector, roll bodies with surfaces protected against wear by hard metal studs are generally used. material operating hours iron ore pellet feed up to 60,000 h hard rock applications up to 20,000 h lifetime hours actually achieved by polycom roll surfaces 6 polycom high-pressure grinding roll 7
the grinding elements of the high-pressure grinding roll are two counter-rotating rolls, between which the material is crushed. one roll is designed as a fixed roll and the other one as a floating roll. the required comminution pressure is transmitted by a hydraulic system via the floating roll. the following features distinguish the
high pressure grinding roll features and performance. the high pressure grinding roll has established itself in various industries. high pressure grinding rolls has been leading the way for the use of hpgr in the non-ferrous metals mining industry. in comminution circuits of the cement and diamond industry, hpgr has become a standard grinding tool.
based on a thorough review of the high pressure grinding rolls hpgr and crushing circuit, a wide range of de-bottlenecking opportunities were identified. this was followed by a series of surveys to provide performance measurements and to model the circuit in detail.
high pressure grinding rolls are used in primary comminution. outotec hpgr solutions are energy efficient technology packages for comminution circuits that enable processing of harder ores. ag and sag mills autogenous and semi-autogenous mills are designed for grinding or primary crushed ore and are the most widely used in concentrators globally.
high pressure grinding rolls hpgr is a mature technology that is proven to reduce capital and operating costs in full scale plants when compared to other comminution technologies. sgs comminution experts have developed a simple testing methodology to avoid some of the difficulties associated with using hpgr.
schönert 1979 has shown that the most energy efficient method of comminuting particles is to compress them between the two plates. compressing a particle bed between two counter rotating rolls was achieved by the invention of the high pressure grinding rolls hpgr schönert and knobloch, 1984 .
results obtained from a laboratory-scale high pressure grinding rolls show that the specific energy consumption of the rolls increases linearly as the applied grinding force increases, but this is not accompanied by a linear increase in the size reduction achieved.
why hpgrs are revolutionising mill circuits chosen for their energy efficiency, long wear life and downstream advantages, high pressure grinding rolls hgprs are increasingly being used at the heart of comminution circuits.
pdf on jan 1, 2006, s. morrell and others published rock characterisation for high pressure grinding rolls circuit design find, read and cite all the research you need on researchgate
the inherent conservatism of the mining industry is well understood, but the current hurdles encountered with financing new projects have complicated instances when new technologies such as high pressure grinding rolls hpgr are considered, especially if it translates into higher capital costs for the project.
grinding circuit design principles. for high pressure grinding rolls and regrind mill sizing, a specific test designed for that piece of equipment is best. basically, the test results estimate the specific energy requirements for crushing, sag milling and ball milling. using a power modelling approach, different mill sizes are selected to
comminution circuits incorporating high pressure grinding rolls hpgrs have been shown to be an energy efficient alternative to conventional circuit designs. the basic operating principle of hpgrs, in which a fairly uniform pressure is applied to a bed of material in the compression zone, results in this improved efficiency morley, 2006 .
high pressure grinding rolls in mineral processing moving from cement to hard rock high pressure grinding rolls hpgrs , also known as roller presses, are rapidly gaining acceptance in hard-rock processing, primarily due to their energy efficiency when applied in comminution. application challenges
to determine work index for high pressure . grinding rolls . abstract. the use of high pressure grinding rolls is gaining significant interest as a replacement for sag milling in the . comminution of hard rock ores because of the potential for reduced costs in terms of energy and grinding ball consumption.
the high pressure grinding rolls hpgr is a relatively new type of equipment, very efficient in terms of energy savings. there are several configurations for comminution circuits that utilize the hpgr technology replacing either ag / sag grinding, or crushing/grinding stages or even as surface generation step prior to iron ore pelletizing.