Gritbuster UNO System
The Gritbuster Uno is designed to quickly process the waste from a number of sweeper/gully tankers by separating rapidly settling solids from liquid. Sweeper/gully vehicles either back up an access ramp (if the unit is not recessed into the ground) and empty the all contents into the reception hopper. The larger, more rapidly settling solids settle to the base of the unit where a horizontal auger screws the settled solids to the end of the unit, from where they are conveyed out of the unit via an inclined auger. The recovered solids can either be dropped directly into a skip or further dewatered on a vibrating deck before dropping into the skip. The dirty water (containing the fine non settling solids) pas through a coarse screen into a dirty water pump, from where it is transferred to the water treatment unit.
• On very small sites handling only a couple of sweepers per day this can be treated with floccluant and the solids separated from the water by filtering it through a dewatering bag located in a 6m RORO skip. Once full of solids the RORO skip can be taken off site for disposal of the bag and contents.
• On larger sites the water can be fully treated to remove the suspended solids by dosing it with a combination of coagulant and flocculate and separating the solids in a lamella clarifier. The recovered solids can either be taken off site as a slurry or further dewatered using a filter press/belt press of centrifuge.
• On arrival at the plant, the vehicle would reverse and discharge directly into the Uno Unit. If the unit is located at ground level, access is via ramp either fabricated from steel (see photo) or built up using granular fill. Alternatively the Uno unit can be recessed into the ground (by locating it in a reinforced concrete or steel box) to avoid the need for a ramp and/or to allow the vehicle to drive over the grating covering the reception hopper.
• The coarse solids rapidly settle to the bottom of the V shaped hopper and after an operator defined time delay are conveyed by a horizontal conveyor to the solids discharge end of the unit. The solids are then transferred from the unit via an inclined dewatering auger and discharged either directly into a holding skip or further dewatered by first passing over a dewatering screen. (If required the material conveyed up by the inclined auger can be split into a coarse and fine fraction by passing it over a double deck screen.)
• The water containing the slow settling solids passes through a coarse screen into a solids handling transfer pump (the coarse screen is designed to prevent large pieces of floating debris- such as plastic bottles from bottles plastic bags etc.)
• The fine solids laden water pumped from the unit can either be pumped directly to the water treatment plant or first passed over the dewatering screen (to remove any sand sized or larger particles) before being forwarded to the water treatment plant.
Waste Water and Fine Solids
Depending on customer requirements and budget, we then have several options for handling the dirty water ranging from a basic storage tank where it can be tankered away, to a full treatment system for discharge to sewer dependant on site specific discharge consents.