So far FGD gypsum has been used mainly in the construction materials i
ndustry, and in fact all the FGD gypsum from coal-fired power stations
is used for this purpose. For FGD gypsum from lignite-fired power sta
tions it is necessary to look for further possible applications becaus
e of the large quantities generated. One of these options could be the
manufacture of calcium sulphate fillers and their application in adhe
sives, paints and plastics. Processing, grinding and classifying proce
sses for FGD gypsum to produce dihydrate fillers have been developed i
n extensive laboratory and pilot-plant trials. Cleaning, drying, grind
ing and classifying has led to two industrially interesting types of f
iller made from FGD gypsum; these were produced and characterized, and
their application in adhesives and paints was investigated. Because o
f the thermal stressing involved, anhydrite fillers are the only ones
suitable for use in plastics, especially in PVC (polyvinyl chloride),
so a process was also developed for producing FGD anhydrite Filer from
FGD gypsum. This FGD anhydrite filler exhibited excellent properties,
in particular high levels of whiteness and high fineness in the 2 mu
m range, and its application in PVC and other thermoplastics and durop
lastics was investigated with good results. This cart be summarized by
stating that, in principle, it is possible to produce calcium sulphat
e fillers from FGD gypsum. The high quality specifications for fillers
were met, especially with respect to fineness and colour. The applica
tion tests in the application medium gave results equally as good as t
hose of competing Filers.