Dissolved air flotation (DAF) is a water treatment process that clarifies wastewaters by removing suspended matter such as oil or solids. This is achieved by dissolving air into the water under pressure and releasing it, causing air bubbles to adhere to suspended particles and causing them to float. DAF is widely used to treat industrial wastewater from facilities like oil refineries, chemical plants, and paper mills. A similar process called induced gas flotation is also used for wastewater treatment. In the mineral processing industry, froth flotation is commonly used to separate minerals.

1. Canoy, Claire E.
2B2- Chemical Engineering Technology
Unit Operations
Engr. Luna
FLOATATION
Dissolved air flotation (DAF) is a water treatment process that clarifies wastewaters (or
other waters) by the removal of suspended matter such as oil or solids. The removal is achieved
by dissolving air in the water or wastewater under pressure and then releasing the air
at atmospheric pressure in a flotation tank or basin. The released air forms tiny bubbles which
adhere to the suspended matter causing the suspended matter to float to the surface of the water
where it may then be removed by a skimming device.
Dissolved air flotation is very widely used in treating the industrial
wastewater effluents from oil
refineries, petrochemical and chemical
plants, natural
gas
processing plants, paper mills, general water treatment and similar industrial facilities. A very
similar process known as induced gas flotation is also used for wastewater treatment. Froth
flotation is commonly used in the processing of mineral ores.
In the oil industry, dissolved gas flotation (DGF) units do not use air as the flotation
medium due to the explosion risk. Nitrogen gas is used instead to create the bubbles.
FLOATATION CHART

2. FLOATATION REAGENTS
Xanthate
Application:
It has a strongest collector ability for sulfide
mineral, and also can be used as diferential flotation
reagent for non-ferrous ore. It’s commonly used in lead
and zinc ore galena mixed priority of the flotation.
Dithiophosphate
Application:
It is efficient collecting agent for sulphide ores
such as sliver sulphide, copper sulphide, lead sulphide
and activation zinc sulphide ore, and also can be used
in flotation of nickel and antimony sulphide
ores.Especially, it is efficient for nickel sulphide ore,
nickel oxide sulphide ores which are difficult for
flotation, sulphide copper and gangue ore. Based on the
research that to use butyl amine aerofloat is beneficial
for recycling of platinum, gold and silver. This
chemical has a light foaming ability.
Thionocarbamate
Application:
Thionocarbamate is an excellent catching agent
for copper sulphide, lead, zinc, molybdenum, nickel
and other minerals. It is the best catching agent of
copper sulphide, efficient, non-poisonous, and has
excellent selectivity, so it is widely used in the world. It
also have foaming ability by itself, so can be used in
acidic or alcaline ore pulp.

3. Thioglycollic Acid
Application:
In addition of being used as the textile auxiliary
& the leather tanning chemicals instead of Sodium
Hydrosulfide;
It also can be used in the main raw material of
cosmetics such as cold wave lotion and depilatory.
Besides;
It also can be used to modulate into PVC and
organic stibium and organic tin.
Isooctyl Thioglycolate, which is produced from
this product after intensive processing, is a heat
stabilizer of non-toxic chlorinated polyolefin
Last, but not least, it acts as an important agent for
metallic ion such as iron, molybdenum, silver and tin,
etc.;
It’s also used in catalyst production in epoxy resin and bisphenol A.
Thioglycolate Salt
Application:
It is used as a depressor for copper mineral and
brasses in copper-molybdenum mine flotation. It is
produced with advanced technology and excellent
craft. It has been used with long period in many
molybdenum flotation factories in China. It has
obvious depressor effect for copper, sulphur and other
material, so it will effectively improve the
molybdenum concentrate level and bring high
economic profit to enterprise. It has been used as a
new-model effective depressor for vulcanization mine
in molybdenum flotation process and can take place
of highly toxic depressor sodium cyanide. This
product has been sold to Henan Luanchuan, Shanxi
Luonan, Fujian JIanyang, Liaoning Huludao etc, and welcomed by our clients. In molybdenum
flotation process, it can not only depress lead, zinc, iron, copper and other metal impurity, but
also has good effect to decrease silicon, sulphur and other non-metal material. This agent needs
only a small dosis, and the usage is easy and convenient, so it can save cost and improve the
economic profit. This product not only can improve the quality, but also without pollution and
hazardous, so it will take positive effect to environment protection of the producing area. It is an
environment protection product and without pollution, which is positively recommend by the
national environment protection department.

4. Dithiocarbamate
Application:
It is effective collctor for copper, lead,
antimonite and other sulfide minerals. It has better
collectivity than xanthate and dithiophosphate, which
is with fast flotation speed and excellent selectivity. If
it is used in flotation under high alkali conditions, it
can improve the separation flotation effect between
lead and zinc, with little or without any cyanide.
Isopropyl (ethyl,isobutyl) xanthogen ethyl
formate
Application:
It is a collecting agent of nonferrous metal
mine, which has better flotation effect than the
related xanthogenate, also has more steady
character and could be used in acidic pulp . It has a
better effect in flotation of separating copper and
sulphur.
Rinsing Reagent
Application:
As Flokal B or Rinsing Reagent，it is
mainly used as oil-removed rinsing reagent in
sewage of oil field or recycled water, or used to
remove the heavy metal ion from industry
sewage.
As an oil-removed rinsing reagent in sewage of
oil field or recycled water, it is mainly used in
gas flotation device for removing oil from
sewage of oil field. First, the oil in sewage can
be flocculated and removed by gas flotation to
make the oil content of sewage reach to the
standard, and then the sewage is quantified to
be discharged or recycled. Specific usage and dosage: after diluting it by 10 times, put it into the
sewage, the dosage is to use 50-1000g for one liter sewage. According to the different dosage
and oil concentration of sewage, the removing percentage of oil in sewage can be above 90%.
As a rinsing reagent used in sewage of oil field, it has better oil-removing effects than usual

5. oil field flocculant--- polyaluminium chloride(PAC), and it has overcame the disadvantages of
huge scum quantity, flco dispersion, breakable and huge liquid water content (>95%) and so on
when
PAC
is
used
in
oil-removing
process.
Meanwhile, it has the effect of emulsion splitter and flocculant, so it has solved the problem that
we must use two or more than two emulsion splitters and flocculants to remove oil and clean
water. Only using it, you can get the effects of oil demulsification in water and flocculant, then
you don’t need to add any other chemicals.
It has already been used in the oil fields of South China Sea, Indonesia and so on.
ZXT Effective Collector For Copper
Application:
It is formula product that aimed at copper
flotation, and has the excellent collecting effect. It is an
efficient, non-toxic, excellent copper collecting agent.
ZX Depressor
Application:
It is series products that aimed at different
mineral characteristic, and different brands can be
chosen with different situations. It is efficient
depressor in molybdenite flotation without using
cyanogen, which can take place of sodium cyanide
and sodium sulfide, and optionally depress copper and
sulphur in molybdenite, especially has the apparently
depressing effect with copper sulphide and pyrite.
Based on different contents of copper, sulphur and
lead in ore, it can be added with one time and one
length or many times and many lengths. The dosage
should be based on flotation experiment, and it is
normally used in alkalic pulp.

6. ZXH EFFECTIVE COLLECTOR
Application:
It is a compound efficient collecting agent
that combined with many kinds of agentia, which is
mainly used in flotation of nonferrous metals mine.
Different brands of this serie can be used with
different characteristics of ore and different
requirements of flotation. It has the characteristics
of high pertinent and excellent flotation effect.
ZXM Frother
Application:
It is mainly used as foaming agent in
flotation of coloured and rare metal and coal,
which has the advantages, such as steady function,
strong foaming ability, fast floating speed,
excellent adaptbility to ore, substantial foam layer,
easy to operate, non-toxic, in favor of improving
environment and decreasing pollution. Different
brands of this serie can be used with different
characteristics of ore .It has the characteristics of
high pertinence and good foaming effect.