Getech spins centrifugal washwater cleaner into tunnelling applications
Centrifugal separators are compact and suited to operation in confined spaces.
Getech, the Italian manufacturer of centrifugal washwater cleaning systems (formerly Gennaretti) is targeting tunnelling operations with containerised versions of its V type machines.
The five-machine range can remove up to 60tonnes an hour of solids from washwater flows of up to 180m3/hr.
The system uses a rotating helical flight shaft (similar to an Archimedes screw) to separate the solids using centrifugal force in the same was as a cyclone air filter. As the contaminants are thrown outwards, the helix pushes them along the machine towards a narrowing taper, which separates the excess water from the solids.
According to the company, the system is only a fraction the size of a traditional filtration plant, making it ideal for tunnelling operations. The water it produces is 99% clean while the outlet cake has a dryness of 65%.
Although the system will accept bigger contaminants, ideally the maximum particle size in the infeed water should be kept to around 73microns to minimise wear.
The system can also recover bentonite from the drilling sludge for re-use and the scroll has a metalised anti-wear surface finish.