Flotation separator hits target market directly
Flotation separation of feldspars from quartz was first accomplished in 1936 and has been used commercially for many years. For example, the feldspar plant at Kona, North Carolina produced from alaskite ore a pottery spar with a maximum amount of 5 percent q:uartz . However, despite its proven successf,l otation still is not used for routine mineral separationsi n the mineralogy laboratory, and has received scant, if anv, attention in most mineralogy texts dealing with mineral separation.
Copper is produced in the U. S. primarily by
pyrometallurgical smelting methods. Pyrometallurgical techniques use heat to
separate copper from copper sulfide ore concentrates. Process steps include
mining, concentration, roasting, smelting, converting, and finally fire and
electrolytic refining.
The writer has found that flotation works admirably
for separation of oligoclasefr om quartz where traditional methodsf ail becauseo
f overlapping densitiesa nd magnetic susceptibilities.A fter flotation, qtartz
in excesso f 3 percentr emainedi n only two of seventeens ampless tudied. This
note is written therefore, to advertize the usefulness of flotation for mineral
separation in the mineralogy laboratorl’ and to demonstrate its applicability
specifically toward the problem of separating oligoclase from quartz.
And for
larger machines in regulated markets, JCB is using Stage IIIB/Tier 4 Interim
Isuzu engines, but for the 20 to 24 tonne cone crushers
that it sells in lesser regulated markets, it will use its own Stage 2/Tier 2
Dieselmax engines.
Copper ore is produced in 13 states. In 1989, Arizona
produced 60 percent of the total U. S. ore. Fourteen domestic mines accounted
for more than 95 percent of the 1.45 megagrams (Mg) (1.6 millon tons) of ore
produced in 1991.
But while the global appeal of excavators and wheeled
loaders has resulted in the launch of two or more machines or machine options in
order to meet the requirements of different markets around the world, the target
market for articulated dump trucks (ADTs) is more-clear cut.
Since these
machines are aimed at the North American and European markets in which they are
traditionally most popular, ball mill
manufacturers have had fewer concerns about making two ranges of
equipment.
Mining produces ores with less than 1 percent copper.
Concentration is accomplished at the mine sites by crushing, grinding, and
flotation purification, resulting in ore with 15 to 35 percent copper. A
continuous process called floatation, which uses water, various flotation
chemicals, and compressed air, separates the ore into fractions. Depending upon
the chemicals used, some minerals float to the surface and are removed in a foam
of air bubbles, while others sink and are reprocessed.