WATER MANAGEMENT & TREATMENT
recommended threshold ( 0.5 mg / L ) specified in the Manganese Removal Bed Module Overview , AMDTreat . However , the MRB achieved only 50 % efficiency due to the wetland ’ s incomplete removal of biochemical oxygen demand , resulting in oxygen depletion within the MRB and inadequate water oxygenation .
The effluent from this pilot-scale passive treatment system she says met the specific discharge limits for the site , except for the Biological Oxygen Demand , which was slightly above the limit . However , after approximately six months , when the BCR reached equilibrium , there was a significant decrease in BOD .
She concludes : “ In the design and configuration of the treatment system , terrain topography must be taken into account to ensure gravity flow and proper circulation and distribution of influent within the system . It is essential to maximise hydraulic retention time so that contaminated water comes into contact with the materials used in these passive technologies . Other important aspects to consider include the available land area for construction , flow rate , and the impact of temperature changes . Furthermore , passive treatment is a holistic approach for water management , that is site specific and is sustainable .”
DELKOR on dewatering
The installation of a DELKOR Paste Thickener to treat iron ore tailings at a plant in India has resulted in significantly reduced water usage , which , in turn , results in environmental benefits for a water-stressed country . The 15 m diameter paste thickener was ordered to increase water recovery within the process plant and increase the life of the existing tailings dam by pumping lesser amount of slurry to it .
Previously , using a conventional thickener , the mine pumped an underflow with 20-25 % ( w / w ) solids directly to the tailings dam , leading to a high loss of water . With the installation of the paste thickener , which was ordered in 2021 and commissioned in 2022 , the solids in the underflow have increased to 50-55 % ( w / w ), increasing the process water recovery to 78-83 % within the plant . This , in turn , has resulted in a significant reduction in the plant ’ s freshwater intake . There has also been a significant reduction in the drying time required by the discharged paste in the tailings dam , which in turn has increased the life span of the tailings dam .
The scope of work covered design , engineering , fabrication and supply of the paste thickener , featuring a forced dilution feed well , with sheer thinning system . It also included design and engineering of the tailings disposal system , featuring a paste pumping system with multiple discharge points for uniform spread inside the tailings dam , plus engineering of ancillary equipment .
“ DELKOR has been proudly associated with this client for nearly 20 years , having previously supplied 16 high-rate thickeners , with diameters ranging from 1 m to 65 m ,” says Indu Bhushan Jha , DELKOR Managing Director . “ We appreciate the ongoing loyalty of such a major steel manufacturer and commend our DELKOR team for providing the quality of service and technologies that have resulted in our client continuing to support us .”
Rajiv Krishnamurthy , DELKOR Executive Director , told IM : “ DELKOR , our TAKRAF Group brand focused on liquid / solid separation , is a leader in dewatering technology for the minerals processing industry . Our portfolio of dewatering solutions includes thickeners , horizontal vacuum belt filters ( HBFs ), and filter presses . These solutions significantly increase water recovery within a plant , which in turn significantly reduces a plant ' s dependence on fresh water supply . Sustainable water management , together with safety , are increasingly important topics for mining operations , investors and stakeholders around the world ; especially in areas where water conservation is critical . With a focus on sustainability , our DELKOR equipment ensures highly efficient and efficient liquid / solid separation and wet processing solutions . In fact , our Group is also ideally positioned to support our clients towards the next significant step in the mining industry ’ s move towards greater environmental sustainability - the transition from wet to dry tailings deposits . This is an area in which the combined strengths of our TAKRAF and DELKOR portfolios will provide for fully integrated solutions that make the difference .”
FLSmidth and dry processing for water savings
Oman-based mining company Vulcan Pelletizing recently placed an order for a range of FLSmidth mineral processing technologies to be installed
FLS options for dry grinding include Vertical Roller Mills
at their upcoming pelletisation plant . The technologies will both reduce water usage and drive operational efficiency . With water being a scarce resource in the Middle East , dry grinding is well-suited to minimise its consumption as well as drive operational efficiency when downstream processing does not require water .
FLSmidth has a long-standing history in supplying dry grinding solutions and has a market-leading position with over 80 sites operating more than 150 FLSmidth dry grinding mills and air separators on various ores , including gold , nickel , lead , zinc , phosphate and iron ore . Its dry grinding portfolio was further strengthened through the Mining Technologies acquisition .
Reducing water is a key focus area for this customer and one of the key reasons FLSmidth says for having chosen its well-proven , dry grinding technologies . This order includes the delivery of two dry grinding mills , a wet grinding
ball mill as well as high efficiency air separators , hydrocyclones and pumps . The equipment is due to be delivered during 2025 . “ Sustainable mining is not only a matter of reducing CO 2 emissions . Reducing water usage in mineral processing stands at the forefront of technologies requested by miners , particularly in water stressed regions and where downstream processing also is dry . This order confirms both our broad , marketleading position within dry grinding as well as supports our MissionZero ambition ,” comments Mikko Keto , CEO at FLSmidth .
Sykes launches XH250 dewatering pump aimed at mining
Sykes Group , a leading name in the realm of dewatering pump solutions , has recently
International Mining | MARCH 2024