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HYDROCYCLONES 32 E&MJ; • FEBRUARY 2018 www.e-mj.com clones are now in use in more than 200 medium- and large-scale iron ore concen- trators in both China and overseas. The other development that Haiwang reported involved the design of a new three-product heavy-media cyclone for use in coal-washing plants, particularly where conventional equipment is ineffi - cient at cleaning coal with high waste and middling contents. With diameters from 500 mm to 1,300 mm, the Haiwang heavy-media cyclones can accept feed sized up to 80 mm, with a re- covery effi ciency of more than 95%. In addi- tion, circulating loads are reduced compared to conventional cyclones, while the energy consumption is around 10% less, under the same conditions and feed pressure. In an operational example at a Chinese coal prep plant, using cyclones with diame- ters of 1,300 mm and 920 mm, the clean coal content in the middling dropped from 39% to less than 10% while the coal re- jected to waste fell from 8% to 2%. Clean coal recovery is 1.5% higher than before, worth around US$6 million in increased sales, and the tonnage of waste for disposal has been reduced by around 100,000 mt/y. Specializing in Separation Established in 1984, Mineral Engineering Processes (MEP) continued with the supply and service of the Stokes range of specialist separation equipment when that company closed in 2000. Today, MEP specializes in mineral process engineering and supplies hydrocyclones, thickener/clarifi ers, Hydro- sizers and other associated equipment. MEP offers seven standard sizes of hydrocyclones between 250 mm (10 in.) and 750 mm (30 in.) in diameter. Accord- ing to the company's managing director, Steven Hyde, in many of the applications with which it has been involved, it has be- come fashionable or advantageous to use numbers of smaller-diameter cyclones. "This is to produce fi ner cut points or to maximize solids recovery and reduce sol- ids being lost in lagoons," he said. MEP hydrocyclones are lined with hot vulcanized soft gum rubber, polyurethane or ceramic tiles, dependent upon the material they are handling. Other liners could be provided if applications or cus- tomers required, Hyde pointed out. MEP cyclones are most commonly used in dewatering applications, in coal, manu- factured sands, silica sands and limestone. "They are designed to deliver optimum effi - ciency, with high availability and wear life," Hyde explained. "The cyclones are mainly welded carbon-steel fabrications, augment- ed with some cast metal or polyurethane components to be able to operate within the harsh environments they are installed in." Hydrocyclone technology plays an im- portant role in the modular fi ne-coal recov- ery plants that MEP designs. In this process, the underfl ow from the raw coal screens is pumped at approximately 15% w/w solids to a four-way in-line cyclone manifold. The excess water and minus-63 µm material is overfl owed and piped to thickeners while the cyclone underfl ow feeds a hindered set- tling classifi er or Hydrosizer. In another example of the company's hydrocyclones in use, MEP was awarded a contract to modify and upgrade the exist- ing de-ligniting sand plant at the Breedon group's Astley Moss quarry in northern En- gland. The process was designed to handle up to 150 t/h of as-dug sand and 100 m 3 /h of water to produce decontaminated con- struction products. In the fl owsheet, both primary and secondary cleaning circuits use hydrocyclones to feed a Hydrosizer. Weir's IOT Approach Weir Minerals told E&MJ; it has developed its own IOT platform, Synertrex, which enables it to optimize the confi guration and design of its products. Currently, the company is optimizing its Cavex hydrocy- clones with the latest Synertrex technolo- gy, enabling operators to detect substan- dard operating conditions such as roping, in order to implement corrective actions and enhance performance. The system remotely monitors the hydrocyclones from a centralized location, and can detect rop- ing, semi-roping and blockage conditions. "The Synertrex platform is connected through advanced sensors fi xed to our Cavex hydrocyclones that transmit data to an in- telligent remote signal processor mounted near each cluster," stated Debra Switzer, Weir Minerals' global product manager for hydrocyclones. "This then converts the sig- nal into alerts that are sent to a central mod- ule that customers can access remotely." The company recently carried out a trial at a copper processing plant in Chile with two out of fi ve of the hydrocyclones connected to the Synertrex platform. Underfl ow and overfl ow samples were taken from the feed while the hydrocyclones were undergoing splash, semi-roping and roping conditions. "Through laboratory analysis we ob- tained the particle size distribution, which enabled us to estimate the hydrocyclones' effi ciency for each of the three conditions. By leveraging the data and slurry samples provided from the system, the plant oper- ators successfully increased their metal- lurgical performance and saw consistent throughput," Switzer explained. Weir Minerals told E&MJ; that it is now trialing its Cavex hydrocyclones with Synertrex technology at a number of sites around the world in preparation for a global launch later this year. The MEP hydrocyclone and Hydrosizer installation at Astley Moss in the U.K., designed to produce construction sand products decontaminated from naturally occurring organic material.