Recovery (evaporation and crystallization) of calcium chloride
(CaCl2) from various resources belongs to our core business
activities since 1980. Calcium chloride is mainly used as agent for gas drying,
for the preparation of cooling brines, as drilling agent, as de-icing agent and
as anti-frosting agent for concrete, as binding agent for de-dusting, and also
for the preparation of solutions as heating media. The product is typically
available in form of flakes and granules with 78% CaCl2 and 95%
CaCl2; for food and pharmaceutical applications in form of
crystallized and over calcined material with 78% CaCl2
The
main production is originated from the Solvay process as by-product to soda ash
as flake material. The concentration of the calcium chloride liquor from this
soda ash process is effected in evaporative crystallizers to avoid
incrustations with Gypsum and sodium chloride. Minor capacities are generated
from the liquid effluents of the flue-gas desulfurization plants behind power
stations and waste incineration units by evaporation crystallization. The
plants here are a combination of a heavy metals precipitation and an
evaporative crystallization with Gypsum seeding.
A recent GEA Messo PT
process innovation is the recovery of a white calcium chloride from the from
the purge liquor of the epichlorohydrine process, rich in organics. This
process design is an assembly of several unit operations and ending up with a
fluidized-bed granulation of some 2 mm diameter white calcium chloride granules
with 78 resp. 95% CaCl2.
A development of GEA Messo PT
during the late 80ties, already, was the evaporative crystallization of
pharmaceutical grade calcium chloride based on calcium chloride solution
prepared by dissolving of limestone in hydrochloric acid, operated since then.