1965/66 saw the addition of a third rotary kiln in the Wietersdorf works. Not only was the first kiln of its kind now almost thirty years old, it could also no longer be run economically. The capacity limits of the works had long been reached, and the time had come to set up a kiln north of the existing plant with a daily output of 1,000 tonnes of Portland cement clinker. (This meant that what was the annual production of the whole of 1913 could now be produced within half a month!). The most extraordinary feature of this kiln was its special burner which allowed for a firing by natural gas, oil and/or coal dust, separately or mixed. Towards the late 80s, more and more surrogate fuels, such as old tyres, processed plastics, etc. started to be used. Externally, too, the kiln underwent a change; it was roofed. And it still rotates although, of course, rebuilt since and with the addition of cutting-edge technological plant components, globally speaking (basically shifting from semi-dry procedure to dry procedure with five-step cyclone pre-heater and calciner).ybr />In this way, the specific internal energy consumption was once more able to be reduced significantly.
