Flotation is a versatile, surface wettability-based separation process, using by mineral processing and chemical engineers for the separation and concentration of variety of different minerals in an aqueous suspensions or solutions, coal enrichment, precipitates and etc.
The basic features of flotation work process are physical, chemical and engineering aspects. Physical aspects investigate particle hydrophobicity and floatability, bubble–particle interactions, froth drainage, and kinetics of flotation process. Surface chemistry of mineral and gangue particles, chemistry of flotation reagents, and mineral–reagent interactions are the main topics that contains chemical aspects of the flotation process. Engineering aspects also contains bubble generation, particle dispersion, and cell design and circuits.
While the concepts have remained more or less unchanged since the concept was first introduced, flotation technology is continuing to advance steadily in all three aspects. Although, enhancements in engineering aspects, especially those related to performance and design of flotation cells, seems to be more salient, since selectivity and cell size being leading drivers of development due to transformation of high grade mineral resources into low grade resources and as a result of facing lower ore grades and more complex mineralogy. Moreover, enrichment of fine particles formed by virtue of low grade ores is another obstacle that makes flotation cell design and manufacturing, much more important.
Flotation cell performance improvements only comes handy by being supported by better communication at all levels between mines, equipment manufacturers and chemical companies. As a result of investments and efforts of manufacturers, some big developments has occurred to optimize recoveries and handle ever-increasing throughput requirements.
A flotation machine has to fulfill three basic functions: (I) Sufficient and wide range of bubble (size range of 0.5–2 mm) which needs a powerful and functionable air-blower and sparger ; (II) Reaching the perfect dispersion of solid materials in order to enhance the chance of bubble paricle collision which needs an efficacious rotor/stator package with high dispersion rate; and (III) precise design of flotation cells which leads to effective collision between particles and bubbles, in addition to providing a quiescent zone for froth formation. Energy consumption and maintenance costs another notable basic factor which should be considered.
To sum up, it can be said that transformation of high-grade resources into low-grade and more complexity of mineralogy, impel engineers to enhance basic flotation cells functions, like suitable bubble size production, maximizing the dispersion and bubble-particle collision by developing the main aspects of flotation: Physical, Chemical and Engineering aspects while considering the lower energy consumption of them. As a result, Innovation and technological developments would be needed to make flotation a suitable approach for treatment of more complex and refractory ores.