A common operational challenge associated with solvent extraction (SX) plants is the effective on-line management of solids introduced from a variety of sources. Solids are often carried over from leaching circuits due to inefficient/incomplete solid/liquid separation. Alternatively, they may be formed as a result of chemical precipitation within the SX circuits or electrowinning (EW) operations. Regardless of the source, solids in SX settlers and EW cells cause operational problems that impact on plant availability and reduce nameplate design capacity.
Even the best designed and optimally operated SX circuits experience problems with entrained solids. Most existing crud and bottom solids removal systems are limited in their effectiveness and operations are often forced to take the impacted settlers off-line for complete removal of solids. These cleaning operations are hazardous, high risk, labour intensive and costly in terms of production downtime and organic reagent loss.
Due to production pressures, operations are often reluctant to take settler units off-line for solids clean-out, resulting in prolonged operation at the below-optimum performance. This often compromises the final metal production rate, product purity, and reagent consumption rates.
The Crud Frogz™ is a solids removal system specifically designed for the on-line removal of entrained interface solids associated with hydrometallurgical SX processes. The system can be used for on-line SX-settler interface crud removal, eliminating the need to interrupt SX unit operation dependent production. Plants using the system, in conjunction with the Crud Forx™ SX settler bottom solids removal technology, have enjoyed prolonged periods of operation without the need to drain settlers for cleaning, even during major crud-runs as a result of poor upstream solid/liquid separation.
The Crud Frogz™ consists of a wide suction head mounted on a tri-wheel system. The crud suction head is custom mounted to always be positioned at the design operating interface level of the client’s SX settlers. The crud suction head can either be connected directly to a removable flexible hose coupling, or to one or more modular lengths of rigid transfer piping. The Crud Frogz™ accessories are available in a variety of materials of construction, suitable for use in most hydrometallurgy environments. The Crud Frogz™ requires a typical crud removal positive displacement pump system generally included in most SX settler designs. The unit can be easily adapted for retrofitting to most crud removal positive displacement installations. This makes the units inexpensive to install and operate.