6V Srl also has a partnership with DECOMAR Spa, which uses a patented environmental dredging technology known as LIMPIDHO® to export contaminated sediments from the bottom of the sea, lakes or rivers without re-suspending particles, the worst enemy for marine ecosystems.
Together with Decomar Spa, 6V can offer the market a continuous closed cycle system for dredging and treating sediments: the Soil & Sediment Washing mobile system. Owing to specific design choices with great treatment capacity, it is able receive the sediments directly from dredging without passing them through the storage bays. In this way, time and money are saved.
Soil & Sediment Washing (S&SW) is an off-site treatment technology that is used to remediate contaminated soils and sediments coming from environmental reclamation, with the objective of maximizing the recovery of material and thus reducing the quantity of waste sent to landfill sites.
S&SW generally consists of granulometric selection and washing materials constituting the solid phase for the total or partial transfer of the contamination in the fine fraction.
The soil fractions with greater granulometry (sands and gravel) are normally sent for recovery whereas smaller particles (mud and clay) in which most of the contaminants are normally concentrated, are sent for treatment or disposal after dehydration.
6V Srl has a mobile Soil and Sediment Washing plant that can treat up to 100 tonnes/hour of contaminated soil, sediment or drilling spoil in order to recover sands and inerts from productive processes or for environmental restoration. The plant is authorized by Italian regulations as a mobile waste treatment plant.
6V Srl’s Soil & Sediment Washing plant is divided into different treatment sections that cover the entire waste treatment process. In general, the following sections can be identified:
The main purpose of this section is to receive the waste and feed it correctly to the plant, eliminating anything that could compromise correct operation.
The section has to:
In this section, transfer takes place of the contaminants from the solid part of the waste to the washing fluid (water or seawater) and separation takes place of the contaminated fractions from the recoverable fractions.
The task of the section is to:
The pulp containing the finer suspended fractions coming from the previous sections is conveyed to the treatment section, where the suspended solids are coagulated and flocculated and then sedimented.
The section thus has to:
The sludge concentrated in the chemical and physical treatment contains most of the contamination and is further dehydrated by mechanisms for separating the solids from the liquid. The main object of treating sludge is to minimize final disposal costs. The plant, depending on site-specific needs, can be provided with two different mechanical dehydration systems that may, in particular cases, be used alongside one another.
Consists of a series of sheets or plates alternating with cloths that adhere to one another to create chambers in which the dehydrated sludge panel is formed. The sludge is pumped at high pressure into the filter. The solid phase is retained in the cavities between plates and frames and from the filter press the liquid phase exits, from which nearly all the suspended solids have been removed. The solid phase is then recovered when the filter press opens, when the quantity of sludge produced has filled the cavity. Filter-pressing is thus a discontinuous process.
Machine consisting of a drum that is partially frustoconical that contains a feed screw. Both the outer drum and the feed screw rotate with slight differences in rotation speed. The solids are separated by centrifugation from the liquids, which accelerates natural sedimentation.
The liquid phase that emerges from the duct located in the upper part of the sedimentation vessel is collected in a storage tank. Most of this water is used in a closed cycle to fluidify and wash soil.
Depending on the type of waste treated and the water content of the waste, the process may have a water deficit or excess. In the former case, water is topped up constantly with water from the industrial grid whereas in the latter case the wastewater completely treated before the waste water is discharged.
Filtration is initially on sand beds (corundum/quartzite) to remove solids and suspended contaminants and then on active carbon bed to remove any dissolved contaminants.
A soil washing laboratory pilot plant with 50 kg/hour capacity
A soil washing pilot plant with 5 tonnes/hour capacity
A line - PFM technology consolidation pilot plant with 5 tonnes/hour capacity