Carrying Capacity

The removal capability of the bubbles is called the carrying capacity and is the general term which characterizes the maximum amount of solids carried by the air bubbles (either in reference to the maximum capacity of the column, or to the maximum capacity per air volume). This refers to the fact that only a specific amount of particles can be attached to and removed by a certain bubble area. Thus, the maximum floatable solids removal or the surface area of attached particles is related to bubble surface area flux.

Typically, the distance between spargers and the slurry-froth interface is between 6 and 12 m. This leads to a substantial mass of particles attached to a bubble (bubble loading).

As bubbles become loaded by collected particles, the contact time between particle and bubble reduces due to the shortening of particle trajectory along the free bubble surface. This means that the rate of collection slows as loading increases, especially when the lower section of a bubble is virtually covered by attached particles. Detachment probability is also much higher for particles attached to the upper hemisphere of a bubble.

Smaller bubbles can carry more solids than larger bubbles, assuming an equal gas rate and that the loaded bubbles have sufficient buoyancy to move against slurry flow. A smaller weight of fine particles can be carried at a constant gas rate and bubble size distribution than that of coarse particles.

Carrying capacity limitations should be taken into account when estimating height-to-diameter ratio for columns working at high overflow (froth) yield. Typical carrying capacity per unit column cross-sectional area for base metal minerals flotation is 2.5 t/(m2 h) and for coal flotation 1.5 t/(m2 h).

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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