Privet • Double Dumper

Application report No 111:
Replacing conventional junk traps in conjunction with high density centrifugal cleaners (cyclones)

The conventional junk/sand trap consists of normally four valves and a junk/sand chamber. It is operated intermittently in a certain sequence in order to take the accumulated junk/sand selected by the cyclone out from the downstream process.

The two main valves take care of that. The two air evacuation valves make sure, that no air is let into the process. This requires a sequence logic software from the process control system and a lot of piping and cables and I/O’s involving considerable cost when installing in the mill. This cost saving estimated at about 6500 EUR compared to installing a conventional junk trap makes this product very attractive.

The Privet Double Dumper® is a single field instrument, thus more simple, reliable and much less costly to install. Additionally it offers improved safety, because it gan never let the full hot pulp flow through.

This product has been installed in many pulp mills both new and existing. In the existing mills it has replaced conventional junk/sand traps with most often not satisfactory knife gate valves. It has showed an improved performance and life time compared to the conventional junk/sand traps. In new mills it has been delivered often with the cyclone manufacturers package.


Read more: