Abstract: A shutter blade comprising a center portion having a receiving and a hooking end. The receiving end has a first opening which connects with a hooking end of another shutter blade. The first opening surface fits into and conforms with the first opening and there is continuous contact therebetween when the hooking end of the other shutter blade and the first opening surface are in a folded state. Alternatively, whether the first opening surface is of opposite shape as the hooking end surface or not, the receiving end can have a second opening separated from the first opening by a common wall. The shutter blade contacts a track mechanism through the second opening. Such shutter blades can be used in a shutter blade assembly in which a plurality of shutter blades are foldably connected in series and movably connected to the track mechanism.

Abstract: Disclosed is a method of producing granulated products from a suspension, which comprises in general the steps of spraying the suspension in a suspension spraying zone, introducing a heat-carrier in the form of a spiral flow to a zone disposed beneath the sprying zone, drying the suspension by the heat-carrier concurrently and countercurrently therewith and separating simultaneously fine fractions of the dried material by means of the same flow of the heat-carrier, with drawing a spent portion of the same, treating thermally the granules produced by drying countercurrently with the aforesaid heat-carrier upon their moving downward in a spiral to a temperature sufficient to ensure the desired product properties, withdrawing processed granules from the thermal treatment zone.

Abstract: Disclosed is a method of thermal treatment of a carbonate suspension yielding lime and CO.sub.2 -containing gas, such suspensions may be those resulting from a filtration sediment for sugar production, comprising in general the steps of dividing the carbonate suspension into two portions, spray-drying these portions both simultaneously and independently, calcining the material produced after suspension drying, cooling the lime produced after calcination, supplying the gas from the calcination zone for spray-drying the first portion of the suspension, withdrawing carbon dioxide recovery from the spent gas after spray-drying the first portion of the suspension, the calcination being carried out by means of the heat of the heat-carrier required for calcinating the material and spray-drying only the first portion of the suspension.