System advantages and application fields
- Low first costs and plant management costs
- High efficiency and reliability for the removal of suspended solids, even colloidal
- Exclusive backwash system which uses raw water rather then filtered water
- External sand recirculation system
- Ease of installation
- Possibility of gravity feed, thanks to its low pressure drops
- Surface water clarification: numerous production units are set up in the proximity of surface water courses, specifically to be able to make use of the natural availability of this resource in the production cycle. However this involves water which necessitates treatment for removal of impurities before it can be used. Sand filtration has always been the most widely used system for the removal of suspended solids. filtrasand was chosen for this application because it combines the efficiency of sand filtration with its continuous operation.
- Rendering water suitable for drinking: in the context of rendering water suitable for drinking filtrasand is inserted among the first stages of treatment. After the taking of water, settling and flocculant clarification, sand filtration permits the capture of the finer solid particles which have not previously been deposited. At the same time, filtrasand permits optimisation of the subsequent phases, particularly the ozonisation. Thanks to its continuous operation the filtrasand filtration bed is always under optimum regeneration conditions. The propensity for choosing it was undoubtedly influenced by the modularity of the system, which allows continual plant extensions.
- Tertiary treatment of civil and industrial wastewaters: it is the sector in which we have the largest number of filtrasand installations. The laws concerning the treatment of sewage, both civil and industrial, are becoming more and more severe. Consequently the limits of the discharge into the receptors are more restricted. For this reason installations must be equipped with a tertiary treatment system, downstream of the secondary clarification, which has a finishing role. filtrasand has been chosen for the indisputable efficiency of sand compared to other means of filtration. Modularity and simplicity of installation are added to this; these features become of fundamental importance when intervention on existing plant is involved.
- Metallurgical industry: filtrasand is employed in the metallurgical industry as one of the treatment phases of the cooling water. The water, appropriately cooled and freed of the suspended solids present in it, can be reused downstream of the process, with unquestionable savings for the end-user companies. Ultra-filtration membrane installations: Ultra-filtration membrane installations require effluent water to be freed from suspended solids and/or fibrous material as much as possible. The membranes are in fact an efficient but extremely delicate support; if subjected to fouling their efficiency is drastically reduced. Suspended solids and fibrous materials have the tendency to deposit themselves on the membranes, accelerating the fouling. To curb this phenomenon it has been proved to be appropriate to treat the water, upstream of the ultra-filtration phase, with a sand filtration. filtrasand avoids the fouling of the membranes, prolonging their life and efficiency. This grants a greater plant lifetime and hence considerable economic savings.
- Active carbon treatment installations: active carbon treatment installations permit the removal of chlorine, ozone, ionic surfactants, solvents, micro-pollutant organic pesticides present in the water, also eliminating every unpleasant odour and taste. filtrasand, installed upstream of the active carbon stage, allows improvement in the features of the entering effluent water. Cleaner water entering the active carbon phase permits longer time intervals between its regenerations, as a consequence saving the costs of regeneration or replacement of the carbon itself.