Manhattan offers a broad range of diamond recovery plants to suit our clients needs and to optimize their operation.
Flow Sort X-Ray Sorter:
Flow Sort technology was established in 1971. There are a few variants available designed to suit different applications. For final recovery one can select a single stage or double twin stage machine. The twin stage machine has two ejectors so each diamond has two chances of being detected, improving machine efficiency. Flow Sort reports up to 98% recovery with their technology. Manhattan has built final recovery plants with 1,2,4 and 8 machines mounted in different configurations as per client requirement.
Typically a complete plant requires a front end washing circuit followed by a scalping screen with storage bins. A conveyor then feeds the X-Ray units from each storage bin, with predetermined size-restricted material to enable optimal recovery efficiency. Automation of the plant to make it hands free is one of the features offered by Manhattan.
Final X-Ray product can be dried and then fed to hands free, sorting glove boxes, with follow-on classification glove boxes and acid washing units.
The Russian Bourevestnik machine is an alternative to the South African Flow Sort technology option and diamond sorting equipment have been available since 1969. Both Bourevestnik and Flow Sort also offer bulk sorting options as concentrating plants. Both companies offer 1mm to 50mm final diamond recovery.
The plant configuration of both suppliers is fairly similar with a front end washing and classification circuit required.
Bourevestnik offers multiple machine options to allow the correct machine to be selected for the application.
Due to a diamonds hydrophobic nature, diamonds stick to diamond grease. Manhattan offers conventional grease table plants with pre-washing, scrubbing if required, and classification into different sizes, before processing over grease. This manual plant can also be offered in a hands-free version with a grease belt, somewhat like a wide conveyor belt, with grease removal, melting, recovery of diamonds and re-application of grease to the belt in an automated hands-free circuit. Diamonds are recovered from the drop box with limited gangue material, which is then hand sorted to recover the diamonds.
Automated grease belt plants may suit projects where there are many small diamonds, and offer a productivity advantage over conventional X-Ray units.
XRT units can act as final recovery units. Typically they are similar to the bulk sorters but configured in final recovery mode. They are more expensive than conventional final recovery X-Rays. Certain diamonds, those with coatings or low fluorescence may benefit from an XRT final recovery instead of a conventional fluorescing X-Ray unit.
Small scale operators often select a bush jig to re-concentrate their rotary pan plant product. Manhattan offers both the simple bush jig and also a 2 stage high tph jigging plant. The advantage being its higher capacity and the fact that is fed with a machine and not by hand. The material would be washed, pre-classified and fed to a rougher and cleaner jig providing a small mass pull more suitable for final X-Ray recovery or hand-sorting.
Many operators utilize a DMS to perform this function but as a jig utilizes water as its concentrating medium instead of ferro silicon, it is far cheaper to operate and has a lower energy consumption. It can also manage a large size range of diamond sizes unlike small tph DMS. Of course the capital cost is also far less than a DMS.
Manhattan also offers a grease table after the jig to eliminate the need for sorting all the gangue product with only the low volume, grease product requiring final inspection.