Mining & Minerals

Our facilities are equipped to identify rheological characteristics and run thorough agitation tests on any type of ore sample. With these results and our experience in the field, we can determine the right mixing intensity and equipment, including optimum type, quantity, and location of impellers.

Carbon-in-pulp (CIP) is the sequential leach then absorption of gold from ore. During the CIP stage, pulp flows through several agitated tanks where sodium cyanide and oxygen have been added to dissolve gold into solution. In the absorption stage, this solution flows through several agitated tanks containing activated carbon. Gold absorbs onto the activated carbon, which flows countercurrent to the pulp, while screens separate the barren pulp from the gold-loaded carbon.

This process is a natural alternative to pressure oxidation for process ores containing sulfides. In essence, bacteria oxidize and break down the sulfide minerals, freeing the occluded metal and making it more amenable to leaching.

We can design a test program to obtain sufficient data for scale-up, as well as guarantee mass transfer in the full-scale tanks.

Typical coal applications include slurry storage, pipeline transfer, and gasification. Some of the present coal slurry installations found in the power generation market, are now the largest in the world.

Pressure oxidation was developed for processing refractory ores where gold is occluded in the sulfide minerals, typically pyrite or arsenopyrite. Oxidation of the sulfides at elevated temperatures and pressures liberates the gold, allowing it to be economically recovered by conventional circuits. Autoclaves have also been recently started up on nickel, copper, & zinc duties to name a few.

Crystallizers are used to separate dissolved solids from purified liquors. The saturated solution is pumped up through a draft tube under a mild vacuum to form crystalline particles. As crystal size grows, the momentum of the larger crystals carries it to an overflow where slurry containing desired particle size is drawn off. Water is then removed to form the final product. Soda ash and potash are good examples.

Lightnin supplies bottom entry units utilizing circulator impellers for this duty. The flow rates of these mixers are critical to achieve successful final results.

In a depressed mining market, Lightnin process engineers can help you maximize your daily operating profits. Our process experts can review your operation on a consulting basis to evaluate key mixing tanks. We can then offer new optimized impeller technology improvements that will reduce operating costs, maximize process results, and increase daily operating profits. Solvent extraction, alumina draft tubes, and mass transfer applications can be improved with Lightnin's Consulting Services.

Lightnin has patented impeller designs that optimize flotation cell process results. We separate the solid suspension and the gas dispersion duties of the process by using industry proven impellers designed for each. Tank design combined with the proper impeller arrangement result in maximum extraction stage efficiency.

Ground up rock slurry is mixed with sulfuric acid and recycled phosphoric acid in either a series of "attack tanks" or in larger volume tanks with draft tube mixers. A mixer must not only suspend phosphoric rock and blend acids; it must also create sufficient velocity to discourage gypsum, a by-product, from building up on the tank walls.

• Attack Tanks
• Isothermal Reactors
• Digesters
• Rock Slurry Tanks
• Pre-flotation Consitioners
• Acid Storage
• DAP Reactor

Ground bauxite is mixed with recycled caustic soda solution (spent liquor" and fed into digesters. With proper agitation, the alumina goes into solution as sodium aluminate.

In the precipitation train, seed particles of alumina trihydrate are introduced to precipitate relatively pure alumina trihydrate crystals from the cooled, super-saturated solution. A low shear draft tube mixer maintains slurry homogeneity at minimum power while minimizing crystal degradation.