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Soda Ash
What is Soda Ash?
Soda ash, also known as sodium carbonate (Na2CO3),
is an alkali chemical refined from the mineral trona or naturally
occurring sodium carbonate-bearing brines (both referred to as natural
soda ash), the mineral nahcolite (referred to as natural sodium
bicarbonate, from which soda ash can be produced), or manufactured
from one of several chemical processes (referred to as synthetic
soda ash).
A series of refining steps are required to produce soda ash from
trona ore. First the raw ore from the mine is crushed and screened.
The materia l
is then fed to rotary calciners and heated. In this process, the
trona decomposes to form crude soda ash, which is dissolved in water.
The insoluble shales are separated from the solution by a combination
of settling and filtration steps, and the resulting insoluble tailings
are taken back into the mine as backfill. The soda ash solution
is treated to remove organic materials yielding a high-purity saturated
solution of sodium carbonate.
Next, the solution is fed to crystallizers where water is
evaporated and sodium carbonate monohydrate crystals are formed.
The industry-familiar term "mono-process" originates
from this process step. The crystals are dewatered and washed
using cyclones and centrifuges, and the solution is recycled
to the evaporator units for further recovery of soda ash. The
monohydrate
crystals are fed to rotary kilns where they are dried to
finished soda ash. Finally, product is screened and
sent to storage silos awaiting rail
and truck loadout.
Where is it used?
Soda ash has a number of diversified uses that touch our lives everyday.
Glass manufacturing is the largest application for soda ash whether
it is in the production of containers, fiberglass insulation, or
flat glass for the housing, commercial building, and automotive
industries. Soda ash also is used to clean the air and soften water.
As environmental concerns grow, demand increases for soda ash used
in the removal of sulfur dioxide and hydrochloric acid from stack
gases. Chemical producers use soda ash as an intermediate to manufacture
products that sweeten soft drinks (corn sweeteners), relieve physical
discomfort (sodium bicarbonate) and improve foods and toiletries
(phosphates). Household detergents and paper products are a few
other common examples of readily identifiable products using soda
ash.
For more information, please contact:
INDUSTRIAL MINERALS ASSOCIATION - NORTH AMERICA
2011 Pennsylvania Avenue, NW, Suite 301
Washington, DC 20006 USA
Tel: 202-457-0200 Fax: 202-457-0287
Web Site: www.ima-na.org
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