The last section of a detergent plant is the Post-Addition Section, necessary in case thermosensitive additives have to be added.

They cannot be introduced in the slurry because the high drying temperatures inside the Spray Tower should decompose them. Normally these additives are necessary for automatic machines formulations hence to produce only hand-washing powder it is possible to avoid this section. Another necessity for Post-Addition Section is when it is desired to increase the detergent bulk density up to 400 - 550 g/l by addition of higher density powders.

Combo process

Various times the most reasonable way to manufacture medium density detergent is by combining (mixing) the low density detergent from a DSD plant (spray drying) together with a high density product from DGC granulation (no-tower).

In this way a medium-high or high density detergent is manufactured at competitive costs, without limitations of formulations or selection of special density raw materials.

In addition using this combined technology there will be an ideal balance between anionic and non-ionic surfactants in the final product.

Of course this is the most expensive solution because foresees either the installation of a DSD plant as well as one DGC.